Circular No. 34/2020/TT-BTTTT Issuing "National Technical Regulations on Short Range Radio Equipment in the Frequency Band from 1 GHz to 40 GHz"

CIRCULAR

ISSUES THE NATIONAL TECHNICAL REGULATION ON SHORT-RANGE WIRELESS DEVICES WITH FREQUENCY RANGE FROM 1 GHZ TO 40 GHZ
the frequency band from 1 GHz to 40 GHz

Pursuant to the Law on Standards and Technical Regulations dated June 29, 2006;

WHEREAS the Law on Telecommunications dated November 23, 2009;November 23, 2009;

WHEREAS the Law on Radio Frequency;November 23, 2009;

WHEREAS Decree No. 127/2007/NĐ-CP dated August 1, 2007 of the Government detailing and guiding the implementation of certain provisions of the Law on Standards and Technical Regulations;

WHEREAS Decree No. 78/2018/NĐ-CP dated May 16, 2018 of the Government amending and supplementing certain articles of Decree No. 127/2007/NĐ-CP dated August 1, 2007 of the Government detailing the implementation of certain provisions of the Law on Standards and Technical Regulations;

Pursuant to Decree No. 17/2017/NĐ-CP dated February 17, 2017, of the Government stipulating the functions, tasks, powers, and organizational structure of the Ministry of Information and Communications;

Pursuant to the proposal of the Director of the Science and Technology Department,

THE MINISTER OF INFORMATION AND COMMUNICATIONS ISSUES THIS CIRCULAR TO REGULATE THE NATIONAL TECHNICAL REGULATION ON SHORT-RANGE WIRELESS DEVICES WITH FREQUENCY RANGE FROM 1 GHZ TO 40 GHZ.

Article 1. ATTACHED TO THIS CIRCULAR IS THE NATIONAL TECHNICAL REGULATION ON SHORT-RANGE WIRELESS DEVICES WITH FREQUENCY RANGE FROM 1 GHZ TO 40 GHZ (QCVN 74:2020/BTTTT).

Article 2. Effective Date

1. This Circular takes effect from July 1, 2021.

2. The national technical regulation on short-range wireless devices with frequency range from 1 GHz to 40 GHz, designated as QCVN 74:2013/BTTTT, stipulated in Clause 6, Article 1 of Circular No. 16/2013/TT-BTTTT dated July 10, 2013 of the Minister of Information and Communications on the issuance of the national technical regulation shall cease to be effective from July 1, 2021.

Article 3. THE HEAD OF THE OFFICE, DIRECTORS OF SCIENCE AND TECHNOLOGY DEPARTMENTS, HEADS OF AGENCIES AND UNITS UNDER THE MINISTRY OF INFORMATION AND COMMUNICATIONS, DIRECTORS OF PROVINCE AND CITY INFORMATION AND COMMUNICATIONS BOARDS UNDER THE CENTRAL GOVERNMENT, AND ORGANIZATIONS AND INDIVIDUALS RELATED TO THIS SHALL BE RESPONSIBLE FOR IMPLEMENTING THIS CIRCULAR.

NATIONAL TECHNICAL REGULATION ON SHORT-RANGE WIRELESS DEVICES WITH FREQUENCY RANGE FROM 1 GHZ TO 40 GHZ

on Short Range Device (SRD) - Radio equipment to be used in the 1 GHz to 40 GHz frequency range
National technical regulation QCVN 74:2013/BTTTT.

Foreword

NATIONAL TECHNICAL REGULATION ON SHORT-RANGE WIRELESS DEVICES WITH FREQUENCY RANGE FROM 1 GHZ TO 40 GHZ TO REPLACE prepared by the Institute of Post and Telecommunications Science and Technology, reviewed by the Department of Science and Technology, and approved by the Ministry of Science and Technology, issued together with Circular No. 34/2020/TT-BTTTT dated November 6, 2020.

NATIONAL TECHNICAL REGULATION ON SHORT-RANGE WIRELESS DEVICES WITH FREQUENCY RANGE FROM 1 GHZ TO 40 GHZ This regulation applies to the following types of short-range wireless devices (SRDs):

on Short Range Device (SRD) - Radio equipment to be used in the 1 GHz to 40 GHz frequency range

National technical regulation QCVN 74:2013/BTTTT.

Chapter 1. GENERAL PROVISIONS

1.1. Scope of Application

- General-purpose short-range radio transceivers: warning, control, remote measurement, data transmission...

- Radio Frequency Identification (RFID) object identification devices;

- Radio location devices: object detection devices, moving object tracking and remote warning or alarm applications.

This regulation applies to products and goods that are short-range wireless devices with HS codes specified in Appendix D.

All short-range wireless devices must comply with regulations on frequency planning and channel allocation in Vietnam. The above-listed wireless devices operate within the 1 GHz to 40 GHz frequency range (as specified in Table 1) in the following cases:

- With external antennas (separate antennas) or internal integrated antennas (built-in antennas);

- Any type of modulation;

- Voice or non-voice.

Table 1 - Permitted frequency bands for short-range wireless devices with frequency range from 1 GHz to 40 GHz

Frequency Band

This technical regulation applies to domestic and foreign agencies, organizations, and individuals engaged in the production and business of devices within the scope regulated by this regulation throughout the territory of Vietnam.

1.2. Applicability

[1] CISPR 16-1-1 (2015): "Specification for radio disturbance and immunity measuring apparatus and methods; Part 1-1: Radio disturbance and immunity measuring apparatus - Measuring apparatus".

1.3. Referenced Documents

[2] CISPR 16-1-4 (2010): "Specification for radio disturbance and immunity measuring apparatus and methods; Part 1-4: Radio disturbance and immunity measuring apparatus - Antennas and test sites for radiated disturbance measurements”. [3] CISPR 16-1-5 (2014): "Specification for radio disturbance and immunity measuring apparatus and methods; Part 1-5: Radio disturbance and immunity measuring apparatus - Antenna calibration sites and reference test sites for 5 MHz to 18 GHz". [4] Recommendation ITU-T .41 (1994): "Psophometer for use on telephone-type circuits".

[5] Recommendation ITU-T .153 (1992): "Basic parameters for the measurement of error performance at bit rates below the primary rate". [6] Commission Implementing Decision (EU) 2017/1483 of 8 August 2017 amending Decision 2006/771/EC on harmonisation of the radio spectrum for use by short-range devices and repealing Decision 2006/804/EC. 1.4.1 Adjacent Channels

Two frequency channels located at a frequency distance equal to the bandwidth of the designated channel from the center frequency of the designated channel. 1.4.2 Alarm Using radio information to indicate hazardous conditions at a particular location.

1.4.3 Artificial Antenna OA non-radiating load with an impedance equal to the output impedance of the device under test, as specified by the manufacturer.

1.4.4 Assigned Frequency Band OThe frequency band in which a wireless device is permitted to operate to perform all designed functions.

1.4.5 Chip

1.4. Terms and Definitions

A modulation unit used in Direct Sequence Spread Spectrum (DSSS) modulation. 1.4.6 Chip Rate

The number of chips transmitted per second.

1.4.7 Conductance Measurement (alarm)

Using radio information to indicate dangerous conditions at a specific location.

1.4.3. Dummy Antenna (artificial antenna)

A non-radiating load with an impedance equal to the output impedance of the device to be measured, as specified by the equipment manufacturer.

1.4.4. Assigned Frequency Band (assigned frequency band)

The frequency band within which a radio device is permitted to operate to perform all functions for which it is designed.

1.4.5. Chip (chip)

The modulation unit used in direct-sequence spread spectrum (DSSS) modulation.

1.4.6. Chip Rate (chip rate)

The number of chips transmitted in 1 second.

1.4.7. Measurement Lead (conducted measurements)

The measurements were carried out using a direct connection with the device under test.

1.4.8. Cumulative on-time (T_{on_cum}) (cumulative on-time (T_{on_cum}))

Total on-time T_on during the observation time T_obs.

1.4.9. Detachable Antenna (dedicated antenna)

An antenna that can be detached and tested with radio equipment, designed as an integral part of the device.

1.4.10. Direct Sequence Spread Spectrum (direct sequence spread spectrum)

A modulation method that combines data to be transmitted with a fixed code sequence for direct modulation of the carrier wave.

1.4.11. Transmission Frequency (duty cycle (DC))

The percentage ratio between the total transmission time T_{on_cum} and the total observation time T_obs within the monitoring bandwidth F_obs.

1.4.12. Equivalent Isotropically Radiated Power (equivalent isotropically radiated power)

The maximum radiated power of the transmitter and its antenna.

1.4.13. Fixed Station (fixed station)

Equipment intended for use at a fixed location.

1.4.14. Frequency Hopping Spread Spectrum (frequency hopping spread spectrum)

A spread spectrum technique where the transmitted signal occupies a set of frequencies over time according to a predetermined schedule.

1.4.15. Identification System (identification system)

A system comprising a transmitter, receiver (or both), and an antenna. This system identifies objects through a transponder.

1.4.16. Integral Antenna (integral antenna)

A fixed antenna that is integrated as an essential part of the device.

1.4.17. Mobile Station (mobile station)

Equipment mounted on mobile means or used as a portable device.

1.4.18. Observation Bandwidth (F_obs) (observation bandwidth)

The bandwidth used for evaluating transmission time.

1.4.19. Observation Period (T_obs) (observation period)

Reference time interval.

1.4.20. Occupied Bandwidth (occupied bandwidth)

The width of the frequency band such that the average radiated power outside this bandwidth is only 0.5% of the total radiated power.

1.4.21. off-time (Toff)

Time interval between two consecutive transmissions.

1.4.22. on-time (Ton)

Time interval on an operating channel (OC) used for transmission purposes.

1.4.23. Operating Channel (OC) (Operating Channel)

The frequency band from F_low to F_high, the device may only transmit signals within this frequency band.

1.4.24. Operating Channel Width (OCW) (Operating Channel Width)

The bandwidth between two frequencies F_low and F_high.

1.4.25. Operating Frequency (operating frequency)

The nominal frequency of the device in operation. This term may be used interchangeably with "central operating frequency."

NOTE: The device may operate at multiple operating frequencies.

1.4.26. Operating Frequency Range (operating frequency range)

The frequency range allowing the device to perform adjustments by tuning circuits, switching circuits, or resetting states.development1.4.27. Out-of-Band Emissions

(out-of-band emissions) Radiation on a frequency or several frequencies simultaneously along with the main radiation outside the necessary bandwidth caused by the modulation process but not being spurious radiation.

1.4.28. Portable Station

(portable station) Equipment that can be moved.

1.4.29. Radiated Measurements

(radiated measurements) Measurements related to measuring absolute field radiation values.

1.4.30. Radiodetermination

(radiodetermination) Determining the position, speed, and other characteristics of an object or collecting information about object parameters using radio wave transmission methods.

1.4.31. Spread Spectrum

(spread spectrum) A modulation technique in which the signal transmission energy is distributed across a wide radio frequency spectrum.

1.4.32. Spurious Emissions

(spurious emissions) Radiation on a frequency or several frequencies outside the necessary bandwidth and the reduction in this radiation level does not affect the quality of communication.

1.4.33. Telecommand

(telecommand) Using radio information to transmit initiating, changing, or terminating signals for a process from a distance.

1.4.34. Telemetry

(telemetry) Using radio information to collect and record data from a distance.

1.4.35. Transponder

(transponder) A device that receives and retransmits the received signal.

1.4.36. Ultra Wide Band (UWB) Technology

(Ultra Wide Band (UWB) technology) Technology for short-range radio communications involving the generation and transmission of intentional radio frequency energy over a very large bandwidth, potentially overlapping some bands allocated for radio services as defined in ITU-R Recommendation SM.1755.

1.4.37. Alternate Adjacent Channels

(alternate adjacent channels) Frequency channels offset from the nominal channel by twice the nominal channel bandwidth.

Figure 1 - Definition of adjacent channels and alternate adjacent channels

1.5. Symbols

      Antenna aperture size

D_{1 ||| I hereby issue this Circular to amend and supplement certain provisions on periodic reporting regimes in Circulars issued by the Minister of Industry and Trade or jointly issued, which shall take effect from February 5, 2020;} E          Electric field strength

f           Frequency

P          Power

R          Distance

t           Time

λ          Wavelength

1.6. Abbreviations

ACS

Chapter 2. TECHNICAL PROVISIONS

2.1. Environmental Conditions

Technical requirements applicable under the environmental conditions for operating equipment published by the manufacturer shall be met. Equipment must comply with all technical requirements of this standard when measurements to meet the requirements in Appendix A are performed under the environmental operating conditions of the equipment.

2.2. Measurement of Compliance with Technical Requirements

2.2.1. Measurement Conditions

The technical requirements of this standard apply under the environmental operating conditions of the equipment as declared by the manufacturer. This equipment must comply with all technical requirements of this standard when operating within the limits of the declared environmental operating conditions.

2.2.2. Measuring Equipment

2.2.2.1. General

Technical documentation and operation manuals for performing measurements must be provided and fully supported.

Fixed mounting equipment for measuring devices with integrated antennas may be provided (see 2.2.7.3).

To simplify and harmonize measurement procedures between different test rooms, measurements must be carried out on sample devices that meet the requirements from 2.2.2.2 to 2.2.2.4. In such cases, the requirements set forth in this standard will be met without the need to perform measurements at all frequencies.

2.2.2.2. Selection of Test Models

If the equipment has optional functions but does not affect radio frequency (RF) parameters, only testing the equipment with a configuration that combines the most complex features is necessary. The equipment to be tested must have an RF 50 Ω output connector for power measurement.

In case the equipment uses internal antennas but lacks a fixed RF 50 Ω connector, a second sample device with a temporary external antenna connection of 50 Ω impedance must be provided, meeting the testing requirements (see 2.2.2.4).

2.2.2.3. Testing Equipment at Different Power Levels

If the equipment to be tested has different transmission power levels due to multiple power modules or additional power stages, or if it has variable transmission frequencies, all relevant information must be declared in the technical documentation. Each power module or additional power stage must be tested together with the equipment. The number of samples required and tests needed should be based on the requirements of 2.2.2. In the simplest case, radiated power emission (e.i.r.p.) and spurious emissions measurements must be conducted for each combination and recorded in the test report.

2.2.2.4. Testing Equipment Without External RF 50 Ω Connector (Equipment with Integrated Antennas)

2.2.2.4.1. Equipment with Temporary or Fixed Internal Antenna Connectors or Using Specialized Measurement Adapters

For measurement support, device access points, fixed or temporary connectors must be clearly marked on the circuit diagram. The equipment supplier may provide suitable measurement adapters. The use of measurement adapters, internal antenna connections, or specific temporary external antenna connections must be recorded in the test report.

Information about measurement adapters is given in 2.2.7.3.

2.2.2.4.2. Equipment with Temporary Antenna Connectors

Radiation can be measured for equipment connected to standard antennas. The equipment supplier must cooperate and assist test laboratories in determining radiation measurement results, removing antennas, and installing temporary external antenna connections.

In other words, there are two types of equipment to be measured in the laboratory: one type connected to a temporary connector, and another type with an antenna connected. Measurements are performed using a combination of these two types of equipment. The party responsible for the equipment to be tested must declare two identical samples in the standard, except for the antenna connector.

2.2.2.5. Testing Non-Continuous Operation Equipment

When conducting transmitter measurements on equipment designed for non-continuous operation, it must be ensured that the transmitter is not activated beyond its maximum operational cycle. The actual operational cycle used must be recorded and stated in the test report.

NOTE: Do not confuse the maximum working cycle of the transmitter being tested with the working cycle of the equipment during normal operation.

When conducting transmitter measurements on equipment designed for non-continuous operation, the operational cycle used may be longer than the normal operational cycle during operation. In such cases, care must be taken to avoid adverse heating effects on the equipment and the parameters being measured. The corresponding maximum cycle time during measurement must be pre-notified by the test laboratory.

2.2.3. Mechanical and Electrical Design

2.2.3.1. General

Transmitters and receivers may be separate units or combined in a single unit.

2.2.3.2. Automatic Transmitter Shutdown Function

If the transmitter has an automatic shutdown function, this function must be disabled during the measurement period. In cases where this function cannot be disabled, an appropriate measurement method will be described and recorded.

2.2.3.3. Disabling Receiver Silence, Noise Reduction, and Battery Saving Functions

If the receiver has a silence, noise reduction, or battery saving function, this function must be disabled during the measurement period. In cases where this function cannot be disabled, an appropriate measurement method will be described and recorded.

2.2.4. Auxiliary Measuring Equipment

Configuration information and dedicated signal sources for measurement must be sent along with the equipment during measurement.developmentm shall be used.

2.2.5. Measurement Power Supply

2.2.5.1. General

The device must be tested using appropriate measuring power sources as specified in 2.2.5.2 or 2.2.5.3. In cases where it is powered by both external and internal power sources, the device must first be tested using an external power source as specified in 2.2.5.2, then repeated using an internal power source as specified in 2.2.5.3.

The measuring power source used must be stated in the measurement report.

2.2.5.2. External measuring power source

During the measurement process, the device's power supply must be replaced with an external measuring power source capable of generating normal and extreme measuring voltages as specified in 2.2.6.2 and 2.2.7.2. The internal impedance of the external measuring power source must be low enough to have an insignificant effect on the measurement results. For measurement purposes, the voltage of the external measuring power source must be measured at the device inputs. The external measuring power source must be isolated appropriately and applied as close as possible to the battery terminals of the device. For radiation measurements, any external power leads must be arranged so as not to affect the measurements.

During measurements, the measuring power source voltage must fall within a tolerance range of < ±1 % relative to the voltage at each measurement point. The value of this tolerance may be very important for certain measurements. Using a smaller tolerance will provide better measurement uncertainty values for these measurements.

2.2.5.3. Internal measuring power source

For radiation measurements on hand-held devices with built-in antennas, fully charged batteries should be used. The batteries used must be supplied or recommended by the manufacturer. If an internal battery is used, the voltage must fall within a smaller tolerance range of ±5 % relative to the initial voltage. In case of non-compliance, a note regarding this effect will be added to the measurement report.

For direct measurements or in cases where a measurement adapter is used, an external power source at the specified voltage level can replace the device's accompanying batteries. This must be recorded in the measurement report.

2.2.6. Standard Measurement Conditions

2.2.6.1. Standard Temperature and Humidity

The temperature and humidity of the measurement room must fall within the following ranges:

- Temperature: from 15 °C to 35 °C;

- Humidity: from 20 % to 75 %.

Where standard measurement conditions cannot be established, specific environmental measurement values must be clearly noted in the measurement report.

2.2.6.2. Standard Measuring Power Source

2.2.6.2.1. Grid Voltage

The voltage of the power source connected to the measuring device must be the rated voltage.

The equipment supplier must declare the rated voltage for each specific device.

The frequency of the alternating current power source must fall within the range of 49 Hz to 51 Hz.

2.2.6.2.2. Battery Power Source

When radio equipment uses a battery, the common measuring voltage is 1.1 times the rated voltage of the battery (6 V, 12 V, etc.).

2.2.6.2.3. Other Power Sources

When the equipment operates with other types of power sources or different types of batteries, the measuring voltage must be declared by the equipment supplier and approved by the measurement laboratories. These values must be recorded in the measurement report.

2.2.7. General Conditions

2.2.7.1. Standard Measurement Signals and Modulation

2.2.7.1.1. General

The modulation measurement signal is a signal used to modulate the carrier wave, depending on the type of device being measured and the required measurements. Modulation measurement signals only apply to devices with external modulation connectors. For devices without external modulation connectors, the internal modulation of the machine should be used for modulation measurement.

The measurement signal used must ensure the following characteristics:

- Characteristic of normal operation;

- Maximum occupied bandwidth.

For pulsed transmitters, the measurement signal must ensure:

- The RF signal generated for each transmission is identical;

- The signal transmission process is stable over time;

- The transmission signal sequence must be accurately repeated;

- Details about the measurement signal must be recorded in the measurement report.

For short-range devices without external modulation measurement connectors, the currently operating modulation should be used for measurement. For narrowband voice (RF bandwidth 120 kHz), an unmodulated signal must be used.

2.2.7.1.2. Standard Measurement Signal for Data

For devices with external connectors for data modulation, the standard measurement signal should be as follows:

a) D-M2: The test signal is a pseudo-random binary sequence of at least 511 bits, continuously repeated, conforming to Recommendation ITU-T O.153. If the signal sequence is not continuously repeated, the actual method used must be clearly stated in the measurement report.

b) D-M3: In cases where selective signaling is used, accompanied by a coder/decoder in the measurement equipment, there must be an agreement between the equipment supplier and the measurement laboratory regarding the measurement signal.development2.2.7.2. Dummy Antenna

A dummy antenna may be used to measure short-range devices, but it must be a pure resistive load. The VSWR at the RF 50 Ω connector end must not exceed 1.5:1 across the entire frequency band of the measurement.

2.2.7.3. Measurement Adapter

2.2.7.3.1. General

For devices with built-in antennas having small aperture openings and no external RF 50 Ω connectors, a suitable measurement adapter must be used.

A measurement adapter is a type of radio equipment used to connect the internal antenna of the machine to the RF 50 Ω terminal device at all frequencies to be measured (Figure 2).

Measurement adapters must be fully described. Additionally, measurement adapters may provide:development a) Connection to an external power source;

b) A method of providing input or output from the device. This may include connecting to or from the antenna. In the case of voice device evaluation, a sound interface may be provided through direct connection or via a sound adapter, or in the case of non-voice devices, the testing equipment may also provide suitable coupling means, such as for data or video output.

Measurement adapters are typically provided by the manufacturer.

The performance characteristics of the measurement equipment must be approved by the measurement laboratory and must comply with the following basic parameters:

a) Coupling loss must not exceed 30 dB;

b) Suitable bandwidth characteristics;

c) Coupling loss variation must not exceed 2 dB across the frequency band used in the measurement.

b) Suitable bandwidth characteristics;

c) The insertion loss variation does not exceed 2 dB over the frequency range used for measurement;

d) The connecting circuit must be a passive or non-linear device-free circuit when connected to the RF coupler;

e) The VSWR at the 50 Ω plug shall not exceed 1.5 over the frequency range of the measurements;

f) The insertion loss must be independent of the position of the measurement coupler and unaffected by the proximity of surrounding objects or people. The insertion loss must be repeatable when the measuring equipment is removed and replaced. Typically, the measurement coupler is fixed in a specified position for the EUT;

g) The insertion loss shall not change significantly when environmental conditions change.

Figure 2 - Measurement Coupler

The field probe (or small antenna) must be terminated correctly. Characteristics and verification will be included in the test report.

2.2.7.3.2. Usage Method

Testing equipment may be used to facilitate certain transmitter and receiver measurements when the device has a detachable antenna.

The measurement coupler shall only be used for relative power measurements or for measurements that are independent of the coupling ratio.

2.2.7.4. Measurement Positions and Overall Layout for Radiation Measurements

The radiation measurement layout diagram and detailed description are provided in Appendix A.

2.2.7.5. Measuring Receiver

The term "measuring receiver" refers to a frequency-selective voltmeter or spectrum analyzer. A true-rms meter is used if not otherwise specified for a specific measurement. The measuring receiver's bandwidth, if possible, should comply with CISPR 16 [1], [2] and [3]. For necessary sensitivity, a narrower measurement bandwidth may be required, and this must be stated in the sample measurement report. Ideally, the measuring receiver's bandwidth should be listed in Table 2.

Table 2 - Preferred Bandwidth Measurement

When using narrowband measurement, apply the following conversion formula:

Where:

A is the measured value at the low measurement bandwidth;

B is the value referred to the standard bandwidth, or

If the measured spectrum consists of discrete spectral lines, use the direct measured value A (Discrete spectral lines are defined as peak pulses higher than the average level by 6 dB in the measurement bandwidth).

2.2.8. Interpretation of Measurement Results

2.2.8.1. General

The interpretation of recorded results in a measurement report for measurements described in this Standard will be as follows:

- The measured values related to corresponding limits will be used to determine whether a device meets the requirements of this Standard;

- The uncertainty value for each parameter measurement must be included in the measurement report;

- The recorded uncertainty value must be, for each measurement, equal to or less than the figures in Table 3.

For measurement methods according to this Standard, the uncertainty figures must be calculated and correspond to the expansion factor (coverage factor) k = 1.96 or k = 2 (providing confidence levels of 95% and 95.45%, respectively, in cases where the actual measurement uncertainty distributions are normal (Gaussian)). The calculation principle of measurement uncertainty is outlined in ETSI TR 100 028, specifically in Appendix F of ETSI TR 100 028-2.

Table 3 is based on such expanded factors.

Table 3 - Maximum Measurement Uncertainty

The specific expansion factor used for evaluating measurement uncertainty must be stated.development 2.2.8.2. Measurement Uncertainty Greater Than Acceptable Maximum Uncertainty

The interpretation of measurement results under this provision is acceptable only for radiated emissions above 26.5 GHz when achieving measurement uncertainties complying with the levels specified in Table 3 is not feasible.

In these cases, only the alternative interpretation process specified in 2.2.8.2 can be accepted.

The results must be interpreted when comparing measured values with specified limits as follows:

a) When the measured value plus the difference between the maximum acceptable measurement uncertainty and the calculated measurement uncertainty by the tester does not exceed the limit value, the tested device complies with the requirements of this Standard.

b) When the measured value plus the difference between the maximum acceptable measurement uncertainty and the calculated measurement uncertainty by the tester exceeds the limit value, the tested device does not comply with the requirements of this Standard.

c) The calculated measurement uncertainty by the tester performing the measurement must be recorded in the measurement report.

d) The calculated measurement uncertainty by the tester may be the maximum value for a range of measured values or the measurement uncertainty for a specific unmeasured measurement. The method used must be recorded in the measurement report.

2.3. Requirements for Transmitters

2.3.1. Measurement Requirements for Transmitters

2.3.1.1. Application

The general requirements in 2.3.1.2 will apply to all EUTs when in transmission mode.

2.3.1.2. Measurement Methods and Limits for Transmitter Parameters

If the transmitter has the capability to adjust carrier power, it must be tested at the highest transmission power level as declared by the equipment supplier. Then, the device must be set to the lowest transmission power level and the false radiation measurement must be repeated (see 2.3.4).oIf the device to be measured has a fixed external RF 50 Ω connector and an integrated or internal antenna, all measurements must be performed with this output. If the connector is not a standardized RF 50 Ω coupler, an appropriate impedance termination circuit must be used. Subsequently, the equivalent isotropic radiated power must be calculated based on the gain of the used antenna.

If the transmitter hasshall the capability to adjust carrier power, its parameters must be measured at the highest transmission power level as declared by the equipment manufacturer. Then, the device must be set to the lowest transmission power level and the radiation measurement repeated (see 2.3.4).

If the device under test has a fixed RF 50 Ω external connector and an integrated antenna or internal antenna, all measurements must be performed using this output. If the connector is not a standardized RF 50 Ω termination, an appropriate impedance matching circuit must be used. Subsequently, the equivalent isotropic radiated power is calculated based on the gain of the used antenna.

If the system includes a responder transmitter, the measurement must be performed with that responder transmitter.

In addition, the following measurements are carried out with either integrated or separate antennas:

a) Equivalent isotropic radiated power (e.i.r.p.) (see 2.3.2)

b) Spurious emissions (see 2.3.3)

2.3.2. Equivalent isotropic radiated power (e.i.r.p.)

2.3.2.1. Application

The requirement for equivalent isotropic radiated power shall apply to all transmitters.

22.3.2.2. Description

e.i.r.p. is the maximum radiated power of the transmitter on its antenna, measured and calculated according to the procedures set forth in the following articles:"b) In addition to the lists of public services issued according to the provisions of Clause 2, Article 4 of this Decree, specialized agencies under provincial People's Committees shall report to the provincial People's Committee for decision-making on amending, supplementing, or issuing the list of public services funded by the state budget within their jurisdiction and consistent with the local budget capacity within the approved budget by the Provincial People's Assembly, and send it to the Ministry of Finance and relevant ministries and sectors for supervision during implementation."2.3.2.3. Measurement procedure

2.3.2.3.1. General requirementsN ||| declaration of customs import procedures.To measure e.i.r.p., first determine the appropriate measurement method (see 2.3.2.3.2 and 2.3.2.3.3). To select the applicable measurement method, the bandwidth of the transmitter at the -6 dB level must be determined using a receiver with a measurement bandwidth of 100 kHz.

At 2.3.2.3.2 for non-spread spectrum transmitters with a -6 dB bandwidth up to 20 MHz and spread spectrum transmitters with a channel bandwidth up to 1 MHz;

At 2.3.2.3.3 for all other transmitter bandwidths.

Using the applicable measurement procedure as described herein and in Appendix A, the output power must be measured and recorded in the test report. The measurement method must be recorded in the test report.

Measurements must be conducted under normal measurement conditions (see 2.2.6).

During measurement, the transmitter must operate in continuous transmission mode.

2.3.2.3.2 Non-spread spectrum transmitters with a -6 dB bandwidth up to 20 MHz and spread spectrum transmitters with a channel bandwidth up to 1 MHz

2.3.2.3.2.1 General

The measurement methods in 2.3.2.3.2.2 or 2.3.2.3.2.3 may only be used for:

- Non-spread spectrum equipment with a -6 dB bandwidth of 20 MHz or less and an operating cycle of over 50%;

- Spread spectrum equipment with a channel -6 dB bandwidth of 1 MHz or less.

A spectrum analyzer or selective voltmeter must be used and adjusted to the carrier frequency of the transmitter where the highest level can be detected.

For FHSS systems, the frequency hopping providing the highest indication level must be used and recorded in the test report.

Other types of transmitters are measured according to 2.3.2.3.3.

2.3.2.3.2.2 The measuring device is a fixed-envelope modulation device

Figure 3 - Measurement setup

Due to practical reasons, measurements are only performed at the highest power level intended for operation of the transmitter. The measurement setup in Figure 3 must be used.

It is preferable to perform the measurement without modulation.

If this is not possible, it must be noted in the test reports.

The transmitter must be set to continuous transmission mode. If this cannot be achieved, measurements must be performed during a shorter period than the signal burst duration. The signal burst duration may need to be extended.

The transmitter must be connected to a dummy antenna and the power supplied to this dummy antenna must be measured.

The equivalent isotropic radiated power is then calculated from the measured value, the known antenna gain relative to an isotropic antenna, and any loss due to cables and connectors in the measurement system.

2.3.2.3.2.3 The measuring device is a non-fixed-envelope modulation device

The measurement is performed with suitable D-M2 or D-M3 signals.

Continuous transmission mode is preferred, otherwise intermittent transmission mode is used.

The transmitter is connected to a dummy antenna and the power to this antenna is measured. The measuring device must have a measurement bandwidth not less than sixteen times the channel bandwidth.

The e.i.r.p. is calculated from: the measured value, the antenna gain, cable loss, and RF connector loss.

2.3.2.3.3 Other transmitters not covered in 2.3.2.3.2

This measurement method applies to:

a) Equipment with a -6 dB bandwidth greater than 20 MHz, and equipment with an operating cycle below 50%, or

b) Spread spectrum equipment with a bandwidth above 1 MHz. The equivalent isotropic radiated power must be determined and recorded.

In the case of radiation measurements on smart antenna systems using symmetric power distribution across available transmit chains, if possible, the EUT must be configured so that only one transmit chain (antenna) is activated while the others are disabled. If this cannot be done, the method used must be recorded in the test report. If only one transmit chain is measured, the measurement result for the active chain must be corrected to be valid for the entire system (all transmit chains).

NOTE: Power (in mW) for one transmit chain must be multiplied by the number of transmit chains to obtain the total power for the system.

The measurement must be performed using the normal operation of the equipment with the applied modulation (see 2.2.8.1).

The measurement procedure is as follows:

- Using appropriate means, connect the transmitter output to a splitter;

- Connect the splitter output to the vertical channel of the spectrum analyzer;

Step 1:

- Adjust the combination of the diode splitter and spectrum analyzer to produce the envelope peaks and operating cycle of the output signal;

- Observe the operating cycle of the equipment [Tx on/(Tx on+Tx off)], which is denoted as x (0 < x < 1);

- Use a calibrated wideband RF power meter to determine the average output power of the transmitter; the observed value is called A;

- e.i.r.p. is calculated from the measured power A, the observed cycle x, and the antenna gain G (in dBi) according to the formula:

Step 2:

P = A + G + 10 log(1/x)

P must not exceed the value specified in 2.3.2.4.

Repeat the measurement for the highest, intermediate, and lowest frequencies of the band in use and record these frequencies in the test report.

FHSS devices must continuously hop across three separate frequencies.

2.3.2.4 Limits

Under normal measurement conditions, the maximum e.i.r.p. of the transmitter must not exceed the values given in Table 4.

Table 4 - Maximum Radiated Power (e.i.r.p.)

Frequency Bands (MHz)

(mW)

2.3.3. Scope of permitted operating frequencies

2.3.3.1. Application

The scope of permitted operating frequencies shall apply to all transmitters.

2.3.3.2. Description

The range of permitted operating frequencies includes all frequencies that the device can utilize within the designated band. The operating frequency range of the device must be declared by the manufacturer.

The operating frequency range of the device is defined by two frequencies: the lowest and highest occupied frequencies of the power spectral envelope according to 2.3.2.4 (Table 4).

F_h is the highest frequency of the power spectral envelope, which is the farthest frequency above the frequency with maximum power, at which the output power falls below the level of -75 dBm/Hz relative to the e.i.r.p. power spectral density (-30 dBm in the standard measurement bandwidth of 30 kHz).ầis the lowest frequency of the power spectral envelope, which is the farthest frequency below the frequency with maximum power, at which the output power falls below the level of -75 dBm/Hz relative to the e.i.r.p. power spectral density (-30 dBm in the standard measurement bandwidth of 30 kHz).

F_l When there are different transmission modes, all modes and their related bandwidths must be specified.

2.3.3.3. Measurement Method

The measurement method for devices using FHSS modulation and stepped frequency modulation is provided in 2.3.3.4.

To measure the operating frequency range, the radiation emission measurement procedure in Appendix A must be used and the results recorded in the test report.

The procedure for measuring the operating frequency range is as follows:

a) Set the spectrum analyzer to the average trace mode with a minimum sweep rate of 50 Hz.

b) Select the lowest operating frequency of the device under test and activate it to transmit in a modulated state. The RF emission of the device will appear on the spectrum analyzer screen.

c) Use the spectrum analyzer's frequency marker to find the lowest frequency where the power spectral density falls below the level specified in 2.3.3.2, and record this frequency in the test report.

d) Use the spectrum analyzer's frequency marker to find the highest frequency where the power spectral density falls below the level specified in 2.3.3.2, and record this frequency in the test report.

e) The frequency difference between the measurements in steps c) and d) is the operating frequency range of the device under test. Record this result in the test report.

This measurement must be repeated for each frequency published by the device manufacturer.

2.3.3.4. Measurement Method for Devices Using FHSS Modulation

The applicable measurement procedure can be used as described in Appendix A, the operating frequency range of the device must be measured and recorded in the test report.

During these measurements, the data stream as specified in 2.2.8.1 will be used. During the measurement, the transmitter must be set to continuous transmission mode. If this is not possible, the measurements must be performed over a shorter period than the continuous signal transmission time. It may be necessary to extend the continuous signal transmission time.n l The transmitter power level must be set to the maximum level if controllable.organize credit institutions, foreign bank branches are responsible for organizing the implementation of this Circular. đThese measurements must be conducted under normal operating conditions. The measurement process must be as follows:

b) Select the lowest hopping frequency of the device under test and activate it to transmit in a modulated state.

c) Find the lowest frequency below the operating frequency where the power spectral density falls below the level specified in 2.3.3.2, and record this frequency in the test report.

d) Select the highest hopping frequency of the device under test where the power spectral density falls below the level specified in 2.3.3.2, and record this frequency in the test report.

b) Select the lowest operating frequency of the device under test and activate it to transmit in a modulated state. The RF emission of the device will appear on the spectrum analyzer screen.

e) The frequency difference between the measurements in steps c) and d) is the operating frequency range of the device under test. Record this result in the test report.

The measurement is repeated for every frequency published by the device manufacturer.

2.3.3.5. LimitsoThe width of the power spectral envelope is the operating frequency range of the device. For devices allowing adjustment or selection of the operating frequency, the power spectral envelope has different positions within the allowed band. The operating frequency range is determined by the lowest frequency F

and the highest frequency F

, resulting from calibrating the device to these frequencies.

The occupied bandwidth (99% of the required radiation) and the required bandwidth must be within the designated band.

For all types of SRD devices, the frequency range must be within the band specified in 2.3.2.4 (Table 4). For devices that are not SRD devices, the operating frequency range of the device may differ between countries._l 2.3.4. Unwanted Emissions in the Out-of-Band Region_h2.3.4.1. Application

Requirements for unwanted emissions in the out-of-band region must be applied to all transmitters.

2.3.4.2. Description

According to CEPT/ERC Recommendation 74-01E and ITU-R SM.329-12 Recommendation, the boundary between the out-of-band and adjacent bands is ± 250% of the occupied bandwidth from the center frequency of the emission. Out-of-band and adjacent band emissions are measured by the power spectral density under normal operating conditions.

Unwanted emissions in the adjacent band (adjacent band emissions) are emissions located within the frequency band 250% wider than the required bandwidth on both sides of the central emission frequency.

2.3.4.3. Measurement Method

2.3.4.3.1. General Requirements

The level of adjacent band emissions will be measured as follows:

a) Power level on a defined load (conducted emissions) and effective radiated power from the test fixture and equipment structure, or

b) Effective radiated power from the test fixture with an antenna in or dedicated antenna, in cases where the device is suitable for such an antenna type and does not have a fixed RF connector.

For measurements above 1 GHz, the maximum value must be measured using a spectrum analyzer. The "hold maximum" function of the spectrum analyzer must be used. For measurements up to 1 GHz, a peak detector set according to CISPR 16 [1], [2], and [3] specifications will be used.

RBW calibration as described in 2.2.7.5 will be applied to the measurement results if applicable.

2.3.4.3.2. Conducted Adjacent Band Emissions

This measurement method applies to transmitters with a fixed RF connector.

Additional requirements for FHSS devices are given in 2.3.4.3.5.

The RBW calibration described in 2.2.7.5 will be applied to the measurement results if applicable.

2.3.4.3.2. Spurious Emission Measurement

This method applies to transmitters with a fixed RF connector.

Some additional requirements for FHSS equipment are provided in 2.3.4.3.5., amended and supplemented by Decree No. 109/2025/NĐ-CP and Decree No. 193/2025/NĐ-CP i external stimulation. Depending on the predictable or random time activation method.

a) The transmitter is connected to the receiver through a measurement load and a loss network with an RF impedance of 50 Ω, and if necessary, a suitable filter is added to prevent overload on the receiver. The bandwidth of the receiver is adjusted to a level where its reception sensitivity is approximately 6 dB lower than the spurious emission level specified in Table 4 (see 2.3.4.4). This bandwidth must be recorded in the measurement report.

To measure spurious emissions below the second harmonic of the carrier frequency, a sharp filter (a sudden cut-off "Q" filter) centered at the carrier frequency with a minimum signal attenuation of about 30 dB must be used.

To measure spurious emissions above the second harmonic of the carrier frequency, a wideband sharp filter with a cut-off greater than 40 dB must be used. The cut-off frequency of the filter must be approximately 1.5 times the carrier frequency.

Preventive measures may be required to ensure that the measurement load does not generate or that the high-pass filter does not reduce the carrier's harmonics.

b) The transmitter must operate in an unmodulated state at the highest power level. If modulation cannot be removed, measure in this state but record it in the measurement report.

c) For carrier frequencies within the range from 1 GHz to 20 GHz, the receiver frequency must be adjusted higher by between 25 MHz and ten times the carrier frequency, but not exceeding 40 GHz. For carrier frequencies above 20 GHz, the receiver frequency must be adjusted higher by between 25 MHz and twice the carrier frequency, but not exceeding 100 GHz, except for the channel the transmitter operates on and adjacent channels. The frequency and level of each detected spurious emission must be recorded in the measurement report.

d) If the receiver is not calibrated according to the output power, the levels of the separated components must be determined by replacing the transmitter with a signal generator and calibrating it to reproduce the frequency and level of the spurious emissions as specified in point c). The absolute power level of each emission must be recorded.

e) The frequency and level of each measured spurious emission must be recorded in the measurement report.

f) If the transmission power can be adjusted, repeat the measurement steps from c) to e) at the lowest possible power level.

g) Repeat the measurements from steps c) to f) for the transmitter in standby mode, if applicable.

2.3.4.3.3. Measurement method - spurious emissions from the device enclosure

This method applies to transmitters with a fixed RF connector.

For transmitters without a fixed antenna connector, see 2.3.4.3.4.

Additional requirements for FHSS equipment are provided in 2.3.4.3.5.

a) The test position is selected according to Appendix A with the requirements for the frequency bands to be measured. The test antenna is initially oriented vertically and connected to the receiver. The receiver bandwidth is adjusted so that its sensitivity is 6 dB lower than the spurious emission limit specified in Table 4 (see 2.3.4.4). The bandwidth used must be recorded in the measurement report.

The transmitter to be measured is connected to a dummy antenna and placed in a fixed position at the standard location and operated in an unmodulated state. If modulation cannot be removed, measure with the modulation but record it in the measurement report.

b) For carrier frequencies within the range from 1 GHz to 20 GHz, the receiver frequency must be adjusted higher by between 25 MHz and ten times the carrier frequency, but not exceeding 40 GHz. For carrier frequencies above 20 GHz, the receiver frequency must be adjusted higher by between 25 MHz and twice the carrier frequency, but not exceeding 100 GHz, except for the channel the transmitter operates on and adjacent channels. The frequency of each detected spurious emission must be noted. If the test position is interfered with by external objects, a shielded measurement room and reduced distance between the test antenna and the transmitter must be used.

The receiver must be recalibrated at each frequency where spurious emission levels need to be measured, and the test antenna raised or lowered through the maximum signal level received by the receiver.

The transmitter must be rotated 360° around the vertical axis to find the maximum received signal level.

The test antenna is raised or lowered multiple times through the maximum field strength obtained and this maximum field strength is recorded.

g) A replacement antenna (see A.3.2) replaces the transmitting antenna at the exact position of the transmitting antenna, in vertical polarization. This antenna is connected to the signal generator.

At each frequency where spurious emissions are measured, the signal generator, replacement antenna, and receiver must be recalibrated. The test antenna is raised or lowered through the maximum signal level that the receiver separates. The level of the signal generator and the signal level of the receiver as in step e) must be recorded.

The frequency and level of each spurious emission measured and the receiver bandwidth must be recorded in the measurement report.

i) Repeat the measurements from step c) to h) with a horizontal polarization test antenna.

j) If the user equipment power can be adjusted, repeat the measurement steps from c) to h) at the lowest possible power level.

k) If possible, repeat the steps from c) to i) for the transmitter in standby mode.

2.3.4.3.4. Measurement method - spurious emissions radiated

This method applies to transmitters with built-in antennas (internal antennas).

Additional requirements for FHSS equipment are provided in 2.3.4.3.5.

a) The test position is selected according to Appendix A with all requirements for the frequency bands to be measured. The test antenna is initially oriented vertically and connected to the receiver, through a suitable filterdevelopment to prevent overload on the receiver if necessary. The receiver bandwidth is adjusted so that its sensitivity is 6 dB lower than the spurious emission limit specified in Table 5 (see 2.3.4.4). The bandwidth used must be recorded in the measurement report.

- Office of the President of the Statedevelopment To measure spurious emissions below the second harmonic of the carrier frequency, a sharp filter (sudden cut-off "Q" filter) centered at the carrier frequency with a minimum signal attenuation of about 30 dB must be used.

To measure spurious emissions above the second harmonic of the carrier frequency, a wideband sharp filter with a cut-off greater than 40 dB must be used. The cut-off frequency of the filter must be approximately 1.5 times the carrier frequency.

The transmitter to be measured must be placed and fixed at the standard position and operated in an unmodulated state. If modulation cannot be removed, test with the modulation but record it in the measurement report.

b) Use the measurement method similar to steps b) and k) of 2.3.4.3.3.

2.3.4.3.5. Additional requirements for FHSS equipment

The measurements are carried out when the transmitter is hopping between two frequencies separated by the maximum hop step declared by the manufacturer, one of which is the lowest frequency.

The measurements are repeated at two frequencies separated by the maximum hop step declared by the manufacturer, one of which is the highest frequency.

2.3.4.4. Limits

The spurious emissions power must not exceed the values in Table 5.

Table 5 - Spurious Emissions

2.3.5. Duty Cycle

2.3.5.1. Application

The duty cycle (DC) shall be applied to all transmitting devices except those using Listen Before Talk (LBT) or Dynamic Adaptive Access (DAA).

This requirement does not apply to devices using Listen Before Talk (LBT).

Transmitters operating in the frequency range from 2 446 MHz to 2 454 MHz transmitting at peak power with a maximum radiation level below 500 mW e.i.r.p. are also exempted.

For devices operating in the frequency range from 2 446 MHz to 2 454 MHz, with a radiation level less than 100 μW e.i.r.p., no duty cycle is specified.

2.3.5.2. Description

The duty cycle is expressed as a percentage of the cumulative transmission time T_{on_cum} within the observation period T_obs. over the observed bandwidth F_obs.

Unless otherwise specified, T_obs is 1 hour and the observed bandwidth F_obs is the operational band. Each transmission consists of RF emission or a series of RF emissions separated by intervals < T_Dis.

A device may operate simultaneously on multiple bands (i.e., multi-transmitting), with the duty cycle for each band applying to each transmission.

In the case of multi-carrier modulation within a band, the duty cycle applies to the entire signal used for transmission (e.g., OFDM).

It should be noted that on some bands, the duty cycle value may depend on the presence of primary radio services.

The device may be activated manually, by internal timing, or by external stimulation. Depending on the activation method, the timing may be predictable or random.into improve efficient spectrum utilization.

2.3.5.3. Measurement Method

The overall duty cycle assessment must be performed during a representative cycle of T_obs over the observed bandwidth F_obs. Unless otherwise specified, T_obs is 1 hour and the observed bandwidth F_obs is the operational band.

The representative time will be the most active time in normal device usage. As guidance, "Normal Use" is considered to represent the behavior of the device during the transmission of 99% of the [radiations] generated during operation.

Setup, operation, and maintenance processes are not considered part of normal operation.

For manually operated or event-dependent devices, with or without software control functions, the manufacturer will declare whether the device has been activated according to a pre-programmed sequence or if the transmitter remains on until activation is released or the device is reset manually. The manufacturer will also provide a description of the application for the device and include typical usage. The typical usage model as published by the manufacturer will be used to determine the duty cycle and compared to the limits in Table 6.

If confirmation is required, an additional transmitter must be added during the measurement process.

2.3.5.4. Limits

Table 6 defines the maximum duty cycle within 1 hour.

Table 6 - Duty Cycle Limits

For equipment with a 100% duty cycle transmitting unmodulated carrier waves for most of the time, a standby-off feature will be implemented to improve spectrum utilization efficiency.development Measurements are repeated at test frequencies for signal generator B approximately 10, 20, and 50 times the channel bandwidth, below the lowest frequency of the receiving channel.

2.3.6. Additional Requirements for FHSS Devices

2.3.6.1. Application

These requirements apply only to devices using FHSS modulation.

2 3.6.2. Description

FHSS devices transmit across multiple channels by moving the transmission frequency from channel to channel.

2.3.6.3. Measurement Method

The total number of hops, dwell time, bandwidth per hop, and maximum hop separation must be declared.

2.3.6.4. Limits

For FHSS modulated devices, at least 20 hopping channels > 90% of the assigned bandwidth must be used.

The dwell time on a single channel must not exceed 1 second. When the device is active (transmitting or receiving), each channel of the hopping sequence must be occupied at least once during the duty cycle, but not more than four times the dwell time on a hop and the number of channels.

2.4. Requirements for Receivers

2.4.1. Types of Receivers

SRD devices are divided into three types of receivers, see Table 7, each type having related receiver requirements and minimum performance criteria. The set of receiver requirements depends on the manufacturer's choice of receiver type.

The manufacturer must correctly identify the type of receiver. Particularly, the manufacturer and user need to pay special attention to the potential interference from other systems operating in the same or adjacent bands that could negatively impact the safety of SRD.

The types of receivers are defined in Table 7.

Table 7 - Types of Receivers

Receiver type 1 or 2 must be used for all devices using LBT or DAA to reduce interference. Receiver type 2 may be required for spectrum access techniques.development2.4.2. General implementation standards

For the purpose of testing receiver performance, the receiver must generate appropriate output under normal conditions as specified below:

- The SND/ND ratio is 20 dB, measured at the receiver output through a weighted telephone network as described in Recommendation ITU-T .41 [4]; or

- After demodulation, the data signal has a bit error rate of 10 Owithout correction; or

- After demodulation, the message acceptance ratio is 80%; or^-2 - The false alarm rate or appropriate sensor criterion as published by the manufacturer.

Unless otherwise specified, when performing measurements, the equipment must be configured for normal operation or the worst-case configuration relevant to the requirements being tested. For each requirement in this standard, this worst-case configuration will be declared by the manufacturer and recorded in the measurement report to ensure that the device is operating in accordance with its intended use. Special software or alternative methods may be used to operate the device in this mode.

2.4.3. Adjacent channel selectivity

2.4.3.1. Application

This requirement applies to channelized receiver type 1.

2.4.3.2. Description

Adjacent channel selectivity is a measure of the receiver's operational capability when there are multiple harmful signals at frequencies different from the useful signal by an amount equal to the adjacent channel spacing of the device.

2.4.3.3. Measurement method

The measurement is only performed under normal conditions.

Two signal generators A and B are connected to the receiver via a combination circuit or:

a) Through a test coupler or test antenna to the receiver's built-in, detachable, or test antenna, or

b) Directly to the fixed or temporary antenna connector input.

Record the signal coupling method with the receiver in the measurement report.

Signal generator A operates at the receiver's nominal frequency for normally modulated desired signal. Signal generator B generates an unmodulated signal and is adjusted to the center frequency of the adjacent channel, immediately above the desired signal frequency.

Initially, signal B is off, using signal A at a sufficient level to establish reliable reception, then increase signal A level by an additional 3 dB.

Turn on signal B, then adjust it to a sufficient level to meet the desired signal specification, record this signal level.

Repeat the measurements with signal B unmodulated and adjusted to the adjacent channel frequency, immediately below the desired signal frequency.

Record the adjacent channel selectivity for the upper and lower channels (in dBm) of the unwanted signal. ofFor tag systems (e.g., RFID, theft prevention, access control, positioning, and similar systems), signal generator A may be replaced by a physical tag located at 70% of the system's measurable range in meters.

In this case, adjacent selectivity must be recorded as the lowest level of the unwanted signal (signal generator B) in dBm that results in unreadable tags.

2.4.3.4. Limitations

The adjacent channel selectivity of the device under specified conditions must not be less than -30 dBm + k. The correction factor k is calculated as follows:

k = - 20 log f

- 10 log

 is the frequency in GHz;

 is the channel bandwidth in MHz. The factor k is limited within the following range: - 40 dB < k < 0 dB. BW

including:

f The measured adjacent channel selectivity must be recorded in the measurement report.

BW 2.4.4. Blocking

2.4.4.1. Application

This requirement applies to all SRD receiver types 1, 2, and 3.

2.4.4.2. Description

Blocking is a measure of the receiver's capability to receive the desired modulated signal without affecting the receiver sensitivity, the reduction in receiver sensitivity caused by unwanted signals entering at any frequency other than those of false responses or occupied bandwidth.

2.4.4.3. Measurement methods

a) Through a test coupler or test antenna to the receiver's built-in, detachable, or

b) Directly to the fixed or temporary antenna connector input.

The signal generator coupling method with the receiver must be recorded in the measurement report.

a) Through a test coupler or test antenna to the receiver's built-in, detachable, or test antenna, or

b) Directly to the fixed or temporary antenna connector input.

Signal generator A operates at the receiver's nominal frequency with normal modulation of the desired signal. Signal generator B generates an unmodulated signal and is adjusted to approximately 10 times, 20 times, and 50 times the channel reception bandwidth above the upper edge of the reception channel.

Initially, turn off signal generator B and signal generator A operates at the receiver's nominal frequency. Then increase signal A level by an additional 3 dB.

Then turn on signal B and adjust it to a sufficient level to meet the requirement and record this signal level.

Repeat the measurements with test frequencies for signal generator B approximately 10 times, 20 times, and 50 times the channel reception bandwidth below the lowest frequency edge of the reception channel.

Blocking or desensitization must be recorded (in dBm) for the lowest level of the unwanted signal (channel B).

For tag systems (e.g., RFID, theft prevention, access control, positioning, and similar systems), signal generator A may be replaced by a physical tag located at 70% of the system's measurable range in meters. In this case, blocking or desensitization must be recorded as the ratio in dB of the lowest level of the unwanted signal (signal generator B) (resulting in unreadable tags) divided by the declared receiver sensitivity and added 3 dB. of2.4.4.4. Limitations

The blocking or desensitization level must be recorded (in dBm) for the lowest unwanted signal level (signal generator B).

For tag systems (e.g., RFID, anti-theft, access control, positioning, and similar systems), signal generator A may be replaced by a physical tag located at 70% of the system measurement range in meters. In this case, the blocking or desensitization level must be recorded as the ratio in dB of the lowest unwanted signal level (signal generator B) (resulting in unreadable tags) divided by the receiver's declared sensitivity plus 3 dB.

2.4.4.4. Limits

Short-range radio devices operating in the frequency band from 1 GHz to 40 GHz within the scope of 1.1 must comply with the technical regulations set forth in this standard.

The blocking level, for any frequency within the designated range, must not be lower than the values given in Table 7, except at frequencies where spurious responses are found.

Table 7 - Blocking Limit or Desensitization Limit

The correction factor k is calculated as follows:

k = - 20 log f - 10 log BW

Where: f is the frequency in GHz

BW is the bandwidth in MHz

The coefficient k is within the range: -40 < k < 0 dB

The measured adjacent channel selectivity must be recorded in the measurement report.

2.4.5. Spurious Emissions

2.4.5.1. Application

The following requirements do not apply to receivers used in conjunction with fixed-position transmitters located at the same place. Fixed at the same location is defined as a distance between the transmitter and receiver under 3 meters. In such cases, the receiver must be measured together with the transmitter using the same operating method.

2.4.5.2. Description

Spurious emissions from the receiver are components of radiation at any frequency generated by the receiver equipment and antenna.

The level of spurious emissions must be measured by:

a) The power level on the specified load (conducted emission) and the effective radiated power from the measuring box and equipment structure, or

b) The effective radiated power from the measuring set and antenna in or dedicated antenna, in the case of mobile equipment suitable for that type of antenna but without a fixed RF connector.

2.4.5.3. Measurement Method for Spurious Emissions

2.4.5.3.1. General Requirements

Additional requirements for FHSS devices are given in 2.3.4.3.5.

2.4.5.3.2. Measurement Method for Conducted Spurious Components

To avoid damaging the receiver, the receiver under test can be connected to a test load and a 50 Ω RF attenuator, combined into a unit with the transmitter.

The receiver under test must have sufficient dynamic range and sensitivity to achieve the required measurement accuracy at the specified limit. The receiver's bandwidth must be adjusted until its sensitivity is at least 6 dB below the spurious emission limit stated in 2.4.5.4. This bandwidth will be recorded in the measurement report: a) The receiver terminal devices must be connected to the test receiver with an RF input impedance of 50 Ω and the receiver must be in operation.

b) For carrier frequencies in the range from 1 GHz to 20 GHz, the test receiver frequency must be adjusted higher by 25 MHz to 10 times the carrier frequency, but not exceeding 40 GHz. For carrier frequencies above 20 GHz, the test receiver must be calibrated higher by 25 MHz to twice the carrier frequency, but not exceeding 100 GHz. The frequency and level of spurious emissions measured must be recorded in the measurement report.

c) If the test receiver is not calibrated according to input power, the levels of the spurious components must be determined by replacing the receiver with a signal generator and calibrating it to produce the frequency and level of spurious emissions as in b). The absolute power level of each spurious component must be recorded.

d) The frequency and level of each measured spurious emission component must be recorded in the measurement report.

2.4.5.3.3. Measurement Method for Radiated Spurious Emissions

This method applies to receivers with a fixed RF connector.

a) The test position is selected according to Appendix A with sufficient frequency band requirements for the measurement being used. The initial test antenna must be placed vertically polarized and connected to the test receiver. The receiver's bandwidth must be adjusted so that its sensitivity is at least 6 dB below the spurious emission limit stated in 2.4.5.4. Record the bandwidth in the measurement report.

The test receiver must be placed and fixed on a stand at the standard position and connected to a dummy antenna.

b) For carrier frequencies in the range from 1 GHz to 20 GHz, the test receiver frequency must be adjusted higher by 25 MHz to 10 times the carrier frequency, but not exceeding 40 GHz. For carrier frequencies above 20 GHz, the test receiver must be calibrated higher by 25 MHz to twice the carrier frequency, but not exceeding 100 GHz. The frequency of each spurious emission component must be recorded. If the test position is interfered with by external radiation, a shielded room or reduce the distance between the transmitter and the test antenna.

c) At each frequency requiring radiation measurement, the test receiver must be calibrated and the test antenna raised or lowered within the highest signal level range that the test receiver can separate.

d) Rotate the test receiver 360° around the axis to find the maximum signal level.

e) Raise and lower the test antenna through the point of the highest signal level. Record this signal level.

f) Replace the test antenna (see A.3.2) with the receiving antenna at the same position and vertically polarized. It is connected to the signal generator.

g) Separate the signal component at each frequency when adjusting the signal generator, replacement antenna, and test receiver. The test antenna is raised and lowered around the maximum signal level. Record the signal level of the test receiver as in step e). After accounting for the gain of the replacement antenna and cable loss, this level will be the spurious emission component at the frequency to be measured.

h) Record the frequency, level of the spurious emission component, and the test receiver bandwidth.

i) Repeat the measurement steps from b) to h) for the horizontally polarized test antenna.

2.4.5.3.4. Measurement Method for Spurious Emission Components

This method applies to receivers with built-in antennas (internal).

a) The test position is selected according to Appendix A with sufficient frequency band requirements for the measurement being used. The initial test antenna is placed vertically polarized and connected to the test receiver. The receiver's bandwidth must be adjusted so that its sensitivity is at least 6 dB below the spurious emission limit stated in 2.4.5.4. Record the bandwidth in the measurement report.

The test receiver must be placed and fixed on a stand at the standard position.

b) The measurements are performed as in steps b) to i) of 2.4.5.3.3.

2.4.5.4. Limits

The power of any spurious emission component must not exceed 2 nW for the frequency range from 25 MHz to 1 GHz and 20 nW for the frequency range above 1 GHz.

Short-range radio devices in the frequency band from 1 GHz to 40 GHz, subject to regulation at 1.1, must comply with the technical specifications in this standard.

3. MANAGEMENT PROVISIONS

3.1. A.3.3. Indoor Antenna

3.2. The testing/measurement for technical requirements specified in 2.4.3 and 2.4.4 of this Standard shall be carried out by domestic laboratories designated, foreign laboratories recognized, or domestic and foreign laboratories recognized in accordance with ISO 17025 standard, or the testing/measurement results provided by the manufacturer.

3.3. The testing/measurement for technical requirements specified in this Standard (except 2.4.3 and 2.4.4) shall be carried out by domestic laboratories designated, or foreign laboratories recognized.

4. RESPONSIBILITIES OF ORGANIZATIONS AND INDIVIDUALS

Organizations and individuals related have the responsibility to implement regulations on conformity certification and declaration of conformity for short-range radio equipment with frequency bands from 1 GHz to 40 GHz, and are subject to inspection by state management agencies according to current regulations.

Chapter 5. ORGANIZATION OF IMPLEMENTATION

5.1. The Department of Posts and Telecommunications and Provincial Departments of Information and Communications have the responsibility to organize the implementation, manage, and inspect enterprises in carrying out this Standard.

5.2. This Standard replaces the National Technical Regulation QCVN 74:2013/BTTTT "National Technical Regulations on Short Range Radio Equipment Frequency Bands 1 GHz-40 GHz".

5.3. In case there are changes, additions, or replacements to the provisions set forth in this Standard, they shall be implemented in new documents.

5.4. During the implementation of this Standard, if any issues arise or difficulties occur, organizations and individuals shall report them in writing to the Ministry of Information and Communications (Science and Technology Department) for guidance and resolution.

ANNEX A

Product Name, Goods According to QCVN

Radiation measurements

A.1 General requirements for radiation field measurement

To measure the radiation field, it is necessary to prepare the measurement location, the equipment to be measured, and antennas with known technical characteristics, calibrated measuring instruments, and accessories such as cables, filters...

This annex sets out minimum requirements and examples of suitable testing.

Measurement locations must be appropriate for radiation tests and should be arranged to minimize mutual interaction effects between objects or materials that can affect each other during the testing process.

Measurement test locations may include:

- Indoor test points;

- Outdoor test points;

- Rooms with partitions.

Required equipment:

- Equipment to be tested and related connecting cables;

- Antennas: testing antennas, dummy antennas, substitute antennas;

- Measuring devices: receiver meters, spectrum analyzers, filters, recording devices...

A.2 Measurement Locations

A.2.1 Outdoor

- The height of the equipment support structure must be at least 3 m or l /2 (at the required frequency).

- The clear area must have a diameter not less than twice the distance between the equipment to be tested and the testing antenna.

- The support structure for the testing equipment must be non-conductive.

- The equipment to be tested must be placed at a height of 1.5 m above the floor and capable of rotating 360° in the horizontal plane.

- The testing antenna must be placed at a height of 1 m to 4 m above the floor.

1: Equipment to be testeddevelopmentGranite, gabbro, decorative stone...

2: Testing antenna

3: High-pass filter

4: Spectrum analyzer

Figure A.1 - Outdoor measurement location

A.2.2 Indoor

Suitable for frequencies above 80 MHz.

The indoor measurement location is described in Figure A.2, where the following requirements apply:

- The ceiling height of the measurement room must be at least 2.7 m,

- The walls on the side of the test equipment and the testing antenna must be at least 7 m apart, and the side walls must be 6 m apart (dimensions 6 m x 7 m).

- The testing antenna must have sensitivity suitable for the entire frequency range to be tested.

Figure A.2 - Indoor measurement location layout

AA.2.3 Measurement location in a shielded room without reverberation

A.2.3.1 General

This is a measurement room where all four walls are made of material that attenuates RF waves. However, this environment cannot be considered a free space for electromagnetic waves, so the attenuation of the test chamber must be calibrated according to Figure A.3 for frequency ranges from 30 MHz to 80 GHz.

Figure A.3 - Specifications for shielding and reflection

HFigure A.4 - Example of the structure of a non-reverberating shielded room47 ||| A.3 Antennas

A.3.1 Test Antenna

For radiation measurement, a radiating antenna from the sample and a substitute antenna must be used. When measuring receiver characteristics, the test antenna is used as a transmitting antenna.

The test antenna support must allow it to be positioned vertically or horizontally polarized, with a height from the center of the antenna varying from 1 m to 4 m above ground level. The test antenna must have a minimum directivity of half the wall reflection limit as shown in Figure A.3.

The length of the test antenna along the measurement axis must not exceed 20% of the measurement distance.

For radiation measurement, the test antenna must be connected to a calibrated receiver meter. The receiver meter must be able to switch to any required frequency.

To measure receiver sensitivity, the test antenna must be connected to a signal generator capable of switching to any required frequency.

There must be the ability to change the height of the antenna to find the maximum radiation point.

A.3.2 Substitute Antenna

To compare the radiation of the device with standard radiation samples, a substitute antenna can be placed at the location of the equipment to be tested.

When measuring up to 1 GHz, the substitute antenna must be a half-wave dipole resonant at the operating frequency, or a shorter antenna but calibrated at half-wavelength. For measurements above 4 GHz, a horn radiator must be used. For measurements from 1 GHz to 4 GHz, either a half-wave dipole or a horn radiator can be used. The center of the antenna must align with the reference point of the test sample.

The distance between the lowest point of the dipole and the ground must be ≥ 0.3 m.

When measuring false radiation and effective radiation power, the substitute antenna must be connected to a calibrated signal generator. When measuring receiver sensitivity, the substitute antenna must be connected to a calibrated receiver meter.

The signal generator and receiver must be connected to the antenna through a combiner and balun.

When using smaller than half-wave dipole antennas, details about the antenna must be recorded in the test report, including calibration factors.

Moving the substitute antenna a distance of ± 0.1 m off-axis from the test antenna in two perpendicular directions to find the maximum received signal. If such a position change causes a signal change greater than 2 dB, the test sample location must be repositioned and the measurement repeated until the 2 dB level change is achieved with the substitute antenna.

A.3.3 Antenna g

Only indoorsinternationaln l

When testing radiation in a measurement box or closed room, a dummy antenna is connected to the device's output port and a non-radiating substitute antenna is used.

Where possible, the dummy antenna should be directly connected to the test sample. If a cable connection is necessary, care must be taken to minimize radiation on that cable.

A.4. Measurement Practices and Auxiliary Measuring Equipment

Antenna characteristics, position, and measuring equipment setup must be recorded in the measurement report. The measuring equipment must be calibrated according to published standards. The equipment to be measured, the antenna, and its cable, along with their characteristics, must be recorded in the measurement report.

Measurement methods must comply with the equipment operation guidelines, with descriptions of measurements and permissible limits provided in technical documentation.

All measuring devices must be calibrated according to current regulations and used in accordance with the operating procedures recommended by the equipment manufacturer.

A.5. Measurement Distance

A.5.1. General

In this annex, measurement frequencies must be greater than 25 MHz and measurement distances must be greater than λ/2 (choose the larger value), at which frequency D has the largest aperture (far field). Outdoor measurement positions are required for low frequencies if indoor, box, or near-field differentiation is not specified.D² / l send a text message l A.5.2. Standard Positioning

Except for wearable devices, standard positioning for all measurements must be as follows:

a) For devices with internal antennas (built-in antennas), they must be placed in the closest position to normal usage conditions as reported by the manufacturer.

b) For devices with external grid antennas, the antenna must be positioned vertically.

c) For devices with external non-grid antennas, the antenna must be mounted on a non-conductive stand at a height equal to that of the measuring antenna.

A.5.3. Auxiliary Cables

The position of auxiliary cables (power supply and micro cables, etc.), if not fully connected, may cause changes in measurement results.

To achieve repeatable results, auxiliary cables must be arranged vertically down (through a hole in the non-conductive support part) or as specified in the technical documentation provided with the equipment.

Care must be taken to ensure that the measurement cable does not adversely affect the measurement results.

General Description of Measurement Methods

Provisions on the HS Code of Terrestrial Mobile Radio Equipment and Terrestrial Radio Relay Equipment

Product Name, Goods According to QCVN

B.1. General

This annex provides an overview of RF signal measurement methods when using measurement positions and setups as described in Annex A. Additionally, it offers methods for measuring radiated emissions based on attenuation calculations instead of direct attenuation measurements.

B.2. Conducted Measurements

Low power levels of the device must be measured according to this standard, conducted emission measurements are applied to devices with antenna connectors. For measuring equipment without suitable end connections, a matching circuit or attenuator with accurate end connections must be used. Subsequently, the radiated power is calculated from the measured value, antenna gain, cable loss, and total system connection losses.

B.3. Radiated Measurement

These measurements are performed with the assistance of measuring antennas and receivers as described in Annex A. The measuring antenna and receiver, spectrum analyzer, or voltmeter must be calibrated according to the procedures outlined in this annex. The test equipment and measuring antenna must be oriented to obtain maximum radiated power. This position must be recorded in the measurement report. The entire frequency range must be measured at this position.

Preferably, radiated measurements should be conducted in a non-reflective measurement room. At other positions, additional adjustments are needed (see Annex A).

a) The measurement position must cover the entire frequency range of the measurement.

b) The transmitter used for measurement must be placed on a stand in the standard position (A.5.2) and in transmission state.

c) The initial measuring antenna must be oriented vertically polarized, unless otherwise indicated. The measuring antenna must be raised and lowered through the point of highest received signal strength. This is not necessary if performed according to A.3.

d) Rotate the transmitter 360 degrees around the vertical axis to find the maximum received signal strength.

e) Raise and lower the measuring antenna multiple times if necessary, to reach the position of maximum field strength. Record this maximum level.

f) Repeat the measurement for horizontally polarized measuring antenna.

g) Replace the substitute antenna correctly in place of the transmitting antenna, vertically polarized. Adjust the signal generator frequency to match the carrier frequency.

h) Repeat steps c) to f).

i) Adjust the signal into the substitute antenna to a level equal to or higher than the receiver separation level from the transmitter.

j) Repeat the measurement for horizontally polarized antenna.

k) Radiated power equals the power supplied by the signal generator increased after calibrating the substitute antenna gain and cable loss.

B.4. Radiated Measurements for Receivers

It is preferable to conduct radiated measurements in a Far Field Range (FAR).

Measurements on receiving devices are essentially the reverse of those on transmitters, with a signal generator connected to the measuring antenna. Calibration is based on the principle of substituting the EUT with a substitute antenna and appropriate measuring equipment. Substitute antenna B.3 is applied (Note that this does not require a practical half-wave dipole, only an antenna with known gain relative to a half-wave dipole).

There are two methods:

a) Connect the substitute antenna to the calibrated receiver and read the direct measurement result.

b) Measure the transmission line loss from the measuring antenna to the substitute antenna and subtract this level from the signal level to obtain the measurement result.

For method a), the received level in some measurements may be too low, thus requiring the signal generator to be increased to an appropriate level and applying equivalent correction to the measurement result.

Method b) means that a calibration measurement can be used for multiple measurements.

Power Limits for RFID Systems Operating in the 2.45 GHz Band

Annex C

Product Name, Goods According to QCVN

C.1. Power Limits and Frequency Bands

.1.1. General Requirements

CParameters for 2.45 GHz RFID devices are given in Table C.1

Table C.1 - Parameters for 2.45 GHz RFID Systems

EIRP Power Limit

C.1.2. Additional requirements for indoor RFID devices operating in the 2,45 GHz band with 4 W e.i.r.p.

Indoor RFID devices with 4 W e.i.r.p. must be designed with two power levels as follows:

a) 4 W - Electronic Information Portal e.i.r.p. and

b) 500 mW e.i.r.p.

The non-reachable power level is 500 mW or less.

The 4 W level may only be enabled by security software installed in the device and can only be accessed by the manufacturer or authorized representative.

C.1.3. Spectrum mask

The spectrum mask declared by the supplier must comply with Table C.2.

Table C.2 - Spectrum mask staircase shape for RFID systems operating in the 2,45 GHz band

Appendix D

Product Name, Goods According to QCVN

HS code for short-range radio equipment

Bibliography

ETSI EN 300 440 V2.2.1(2018-07): "Short Range Devices (SRD); Radio equipment to be used in the 1 GHz to 40 GHz frequency range; Harmonised standard for access to radio spectrum".

ANNEX

Chapter 1. GENERAL PROVISIONS

1.1. Scope of Application

1.2. Applicability

1.3. Referenced Documents

1.4. Terms and Definitions

      Antenna aperture size

ACS

Chapter 2. TECHNICAL PROVISIONS

2.1. Environmental Conditions

2.2. Measurement of Compliance with Technical Requirements

2.2.1. Measurement Conditions

2.2.2. Measuring Equipment

2.2.3. Mechanical and Electrical Design

2.2.4. Auxiliary Measuring Equipment

2.2.5. Measurement Power Supply

2.2.6. Standard Measurement Conditions

2.2.7. General Conditions

2.2.8. Interpretation of Measurement Results

2.3.1. Measurement Requirements for Transmitters

2.3.1.1. Application

2.3.2. Equivalent isotropic radiated power (e.i.r.p.)

2.3.3. Scope of permitted operating frequencies

According to CEPT/ERC Recommendation 74-01E and ITU-R SM.329-12 Recommendation, the boundary between the out-of-band and adjacent bands is ± 250% of the occupied bandwidth from the center frequency of the emission. Out-of-band and adjacent band emissions are measured by the power spectral density under normal operating conditions.

2.3.5. Duty Cycle

2.3.6. Additional Requirements for FHSS Devices

2.4. Requirements for Receivers

2.4.1. Types of Receivers

For the purpose of testing receiver performance, the receiver must generate appropriate output under normal conditions as specified below:

This requirement applies to channelized receiver type 1.

2.4.4.2. Description

2.4.5. Spurious Emissions

3. MANAGEMENT PROVISIONS

4. RESPONSIBILITIES OF ORGANIZATIONS AND INDIVIDUALS

Chapter 5. ORGANIZATION OF IMPLEMENTATION

Appendix A (Provisions) Radiation measurements

Appendix B (Provisions) General description of measurement methods

Appendix C (Provisions) Power limits for RFID systems operating in the 2,45 GHz band

Appendix D (Provisions) HS code for short-range radio equipment

Bibliography