Circular No. 32/2016/TT-BTTTT Issuing the "National Technical Regulation on Personal Locator Beacons Operating on the 406.0 MHz to 406.1 MHz Band"

 

CIRCULAR

ISSUING "NATIONAL TECHNICAL REGULATION ON PERSONAL LOCATOR BEACON OPERATING IN THE 406.0 MHz TO 406.1 MHz FREQUENCY BAND"

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

Pursuant to the Law on Telecommunications dated 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 Technical Standards and Regulations;

Based on Decree No. 132/2013/ND-CP dated October 16, 2013 of the Government on 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 stipulate the National Technical Regulation on Personal Locator Beacon operating in the 406.0 MHz to 406.1 MHz frequency band.

Article 1. Attached herewith is the National Technical Regulation on Personal Locator Beacon operating in the 406.0 MHz to 406.1 MHz frequency band (QCVN 108:2016/BTTTT).

Article 2. This Circular takes effect from October 1, 2017.

Article 3. The Heads of the Office, Department of Science and Technology, Heads of agencies and units under the Ministry of Information and Communications, Directors of Provincial Departments of Information and Communications, and organizations and individuals related thereto shall be responsible for implementing this Circular.

 

QCVN 108:2016/BTTTT

NATIONAL TECHNICAL REGULATION ON
PERSONAL LOCATOR BEACON OPERATING IN THE 406.0 MHz TO 406.1 MHz FREQUENCY BAND

National technical regulation
on Personal Locator Beacon (PLB) operating in the 406.0 MHz to 406.1 MHz frequency band

Table of Contents

Chapter 1. GENERAL PROVISIONS

1.1. Scope of Application

1.2. Applicability

1.3. Referenced Documents

1.4. Terms and Definitions

1.5. Abbreviations

Chapter 2. TECHNICAL PROVISIONS

2.1. General Requirements

2.2. Environmental Testing

2.3. Transmitter

2.4. Signal Format

2.5. PLB Beacon Coding

2.6. Power Supply Requirements

2.7. Radiated Power

2.8. Homing Device

3. MEASUREMENT METHODS

3.3. Essential Parameters for the Wireless Part

3.2. Measurement Method

5. RESPONSIBILITIES OF ORGANIZATIONS AND INDIVIDUALS

5. RESPONSIBILITIES OF ORGANIZATIONS AND INDIVIDUALS

6. IMPLEMENTATION ORGANIZATION

ANNEX A (Provisions) Environmental Testing

ANNEX B (Provisions) Coding Method

ANNEX C (Reference) Test Setup Diagram

QCVN 110:2017/BTTTT was compiled by the Post and Telecommunications Science and Technology Institute, reviewed by the Department of Science and Technology, and promulgated along with Circular No. 24/2017/TT-BTTTT dated October 17, 2017.

 

Foreword

QCVN 108:2016/BTTTT is based on the European Telecommunications Standards Institute (ETSI) standard ETSI EN 302 152-1 and the documents C/S T.001, C/S T.007, C/S G.005, C/S T.012 of the Cospas-Sarsat organization.

QCVN 108:2016/BTTTT was compiled by Vietnam Marine Electronics Joint Stock Company Limited, reviewed by the Department of Science and Technology, and issued by the Ministry of Information and Communications pursuant to Circular No. 32/2016/TT-BTTTT dated December 26, 2016.

 

AMENDMENT 1:2025 QCVN 07:2023/BXD
ON PERSONAL LOCATOR BEACON OPERATING IN THE 406.0 MHz TO 406.1 MHz FREQUENCY BAND

National technical regulation
on Personal Locator Beacon (PLB) operating in the 406.0 MHz to 406.1 MHz frequency band

Chapter 1. GENERAL PROVISIONS

1.1. Scope of Application

This regulation sets out quality requirements and technical characteristics for personal locator beacons (hereinafter referred to as PLBs) operating within the Cospas-Sarsat satellite system. This regulation applies to PLBs operating in the 406.0 MHz to 406.1 MHz frequency band.

This regulation applies to PLBs operating within the temperature range:

- From -40°C to 55°C (Type 1 PLB), or

- From -20°C to 55°C (Type 2 PLB).

1.2. Applicability

This regulation applies to organizations and individuals, both domestic and foreign, engaged in the production and business of equipment within the scope regulated by this regulation on the territory and territorial waters of Vietnam.

1.3. Referenced Documents

C/S T.001 Issue 3 - Revision 16 December 2015.

C/S T.007 Issue 4 - Revision 10 December 2015.

C/S T.012 Issue 1 - Revision 11 December 2015.

1.4. Terms and Definitions

1.4.1. Personal Locator Beacon (Personal Locator Beacon)

A Personal Locator Beacon is a personal position indicator device used to transmit distress signals in the 406.0 MHz to 406.1 MHz frequency band.

1.4.2. Type 1 Personal Locator Beacon (Category 1 PLB)

The Personal Locator Beacon must have the capability to float on water.

1.4.3. Type 2 Personal Locator Beacon (Category 2 PLB)

The Personal Locator Beacon does not necessarily have the capability to float on water.

1.4.4. Class 1 Personal Locator Beacon (Class 1 PLB)

The Personal Locator Beacon designed for activities within the temperature range from -40°C to 55°C.

1.4.5. Class 2 Personal Locator Beacon (Class 2 PLB)

The Personal Locator Beacon designed for activities within the temperature range from -20°C to 55°C.

1.4.6. Homing Device (Homing Device)

An auxiliary radio locating signal transmitter at 121.5 MHz frequency integrated inside the Personal Locator Beacon.

1.5. Abbreviations

Chapter 2. TECHNICAL PROVISIONS

2.1. General Requirements

2.1.1. Operating Requirements

The PLB buoy must be designed to operate effectively under weather conditions, on shore, on deck, and on life rafts. The equipment shall not be affected by contact with seawater, oil, or direct sunlight.

The PLB buoy may be equipped with a positioning device capable of global operation, such as a GNSS receiver.

The structure and operating method must prevent accidental operation at high levels but still ensure simple operation in emergency situations.

The PLB buoy can only be activated manually.

The time from activation of the PLB buoy to the transmission of distress signals must be within 47 seconds to 5 minutes. The PLB buoy must be an integrated unit including both power source and a fixed antenna. Components of the device cannot be easily removed. The distress signal part must be retained so that it is not affected when the entire power supply is lost. All external connections must not hinder the activation of the PLB buoy.

2.1.2. Buoyancy

Type 1 PLB buoys must have the ability to float on water.

Type 2 PLB buoys do not necessarily need to have the ability to float on water.

2.1.3. Color

The body of the PLB buoy must be yellow or orange.

2.1.4. Control Parts

All control parts must be of sufficient size for easy and convenient operation.

The PLB buoy must have clear indicators showing that the device has been activated by removing the protective part or seal that the user cannot replace. Activation of the device must be performed by two simple but independent actions. The activation part or seal must remain intact during testing.

The manual activation part of the PLB buoy must be protected against accidental activation.

After activation, the PLB buoy can be deactivated manually.

2.1.5. Indicators

The PLB buoy must have sound or visual indicators to show that the device has been activated.

2.1.6. Self-test Mode

The PLB buoy must have the ability to self-test without using satellite systems to determine that the PLB buoy can operate properly. At least the following items must be checked under full load conditions:

- Battery voltage must be sufficient to meet the power supply requirements for the PLB buoy;

- The radio frequency transmitter output on the 406.0 MHz to 406.1 MHz band must be operational;

- If a phase-locked loop (PLL) is used on the 406.0 MHz to 406.1 MHz band, the phase must be locked.

When this mode is activated, the PLB buoy will transmit a single burst providing the buoy identification code 15 Hex, the frame synchronization pattern will be "011010000" (i.e., the last 8 bits of the standard frame synchronization pattern (from bit 17 to bit 24 of the beacon) are replaced and the burst length must be 440 ms or 520 ms). Successful completion of the self-test mode must be indicated after the automatic test components stop activating. The self-test mode must function within the operating temperature range.

If a navigation signal is transmitted during self-testing, the PLB buoy must have a label indicating that self-testing can only be performed in the first 5 minutes of any hour and not more than three sweeps of low frequency or 1 second.

2.1.7. Labels

The PLB buoy must have one or more labels containing the following information (at least in English):

- Model designation, serial number, and manufacturer's instructions regarding the type of battery used;

- Date when the battery needs to be replaced;

- Full instructions for manual activation, deactivation, and self-testing;

- Warning that the PLB buoy should only be used in emergencies;

- Temperature range according to the type of equipment;

- Floating or non-floating for Type 1 or Type 2 PLB buoys;

- The 15 Hex identification code programmed in the PLB buoy determined by bits 26 to bit 85 of the digital message;

- Safety terms related to batteries;

- For Type 2 PLB buoys, there must be a warning that this is a non-floating type. The label must be easily readable and non-erasable.

2.1.8. Operating Instructions

The equipment manufacturer must provide complete instructions related to storage, operation, and testing of the PLB buoy. These instructions include:

- Overview of the COSPAS-SARSAT system;

- Information related to registration, renewal of registration, and a mention of the importance of accurate registration;

- Warning against false alarms and guidance on reporting when the PLB buoy is accidentally activated;

- Instructions for replacing batteries, including warnings about replacing batteries after the PLB buoy has operated for any purpose other than testing;

- Recommendations for operating the PLB buoy in open spaces rather than trying to operate it inside life rafts or under any shelter or tent;

- Manufacturer recommendations (if any) for periodic functional checks, which may relate to battery replacement;

- Recommendations for limiting self-tests to the minimum necessary to ensure reliable operation of the PLB buoy;

- Recommendations for the PLB buoy when transmitting a 121.5 MHz signal during self-testing, with a warning about limiting tests in the first 5 minutes of the hour;

- Recommendations to retain the original packaging box of the PLB buoy because it may be needed if the PLB buoy must be sent for maintenance;

- For Type 2 PLB buoys, there must be a warning that this buoy will not float;

- Warranty information;

- Information on battery disposal.

2.1.9. Navigation Equipment

If the PLB buoy is equipped with navigation equipment operating at 121.5 MHz, the navigation equipment must meet the requirements set out in 2.8.

2.1.10. Auxiliary Equipment

Any auxiliary equipment of the PLB buoy must still meet all the requirements of this standard.

2.2. Environmental Testing

Environmental tests are used to determine the equipment's operability under different environmental conditions, including:

- Temperature test;

- Vibration test;

- Impact test;

- Corrosion test;

- Drop test;

- Thermal shock test;

- Water immersion test;

- Floatability test.

Definitions, test methods, and corresponding requirements are detailed in Appendix A.

2.3. Transmitter

2.3.1. Emission Frequency

2.3.1.1. Definition

The frequency of the unmodulated signal emitted by the PLB buoy.

2.3.1.2. Requirements

The channels of the PLB buoy must fall within the band defined by Cospas-Sarsat, specifically as stipulated in document C/S T.012, while the frequency deviation must not exceed the following values:

(*): Added later, must comply with the frequency regulations of Cospas-Sarsat in document C/S T.012.

- Short-term frequency stability: frequency stability at the time of manufacture.

- Long-term frequency stability: frequency stability within five years from the time of manufacture. Follow the measurement method at 3.2.1.

2.3.2. Output power

2.3.2.1. Definition

The output power of the transmitter is the power measured with a 50 Ω load.

2.3.2.2. Requirements

The output power shall be: 37 dBm ± 2 dB.

Follow the measurement method at 3.2.2.

2.3.3. Spurious emissions

2.3.3.1. Definition

Spurious emissions are unwanted emissions measured in the band from 406.0 MHz to 406.1 MHz.

2.3.3.2. Requirements

Spurious emissions shall not exceed the levels defined by the spectrum mask in Figure 1. The resolution bandwidth of the spectrum analyzer is 100 Hz. Follow the measurement method at 3.2.3.

"5. The pre-tax weighted average cost of capital i (%) is determined according to the formula below:_c = Unmodulated carrier output power of the PLB.

P_c = Carrier frequency of the PLB.

dBc = Power level difference of the PLB emission signal relative to P expressed in dB._c Figure 1. Spectrum mask on the band from 406.0 MHz to 406.1 MHz

2.3.4. Data encoding

2.3.4.1. Definition

Data is encoded in two-phase L as shown below:

Figure 2. Data encoding

2.3.4.2. Requirements

Data must be encoded in two-phase L as shown in Figure 2.

Follow the measurement method at 3.2.4.

2.3.5. Modulation

2.3.5.1. Definition

The carrier wave is phase-modulated with peak values of (+1.1 ± 0.1) rad and (-1.1 ± 0.1) rad relative to the unmodulated carrier wave.

The rise modulation time (t

) and fall modulation time (t_{||| R}) of the modulated waveform are the times measured between points 0.9 of the phase transition peaks (Figure 3)._FSymmetry modulation is the difference between the intervals T

and T₁ as determined in Figure 4.₂ Figure 3. Rise and fall modulation times

Figure 4. Symmetry modulation

2.3.5.2. Requirements

The rise and fall modulation times of the modulated waveform must be: 150 μs ± 100 μs.

The symmetry modulation must satisfy:

Follow the measurement method at 3.2.5.

2.3.6. Voltage Standing Wave Ratio

2.3.6.1. Definition

It is the ratio that the modulator and transmitter for the 406.0 MHz to 406.1 MHz band must be capable of meeting all requirements without damage due to open or short circuit loads, except for the output power requirements.

2.3.6.2. Requirements

The voltage standing wave ratio must be between 1:1 and 3:1. Follow the measurement method at 3.2.6.

2.3.7. Maximum Continuous Transmission Time

2.3.7.1. Definition

The PLB buoy must be designed to limit accidental continuous transmission of signals on the 406.0 MHz to 406.1 MHz band for more than 45 seconds.

2.3.7.2. Requirements

The maximum continuous transmission time must be ≤ 45 seconds.

Follow the measurement method at 3.2.7.

2.4.1. General Requirements

2.4. Signal Format

The transmitted signal from the PLB buoy includes the unmodulated carrier signal and the digitally modulated data portion. This signal is transmitted over a period of time with a defined repeating cycle.

Figure 5. Transmission Time Diagram

2.4.2. Repeating Cycle

2.4.2.1. Definition

The repeating cycle (TR) is the time interval between the start points reaching 90% of the transmission power (0.9 PN) of two consecutive transmissions.

2.4.2.2. Requirements

The repeating cycle must be random to ensure that no two buoys transmit at the same time. The repeating cycle (TR) must be within the range of 47.5 s to 52.5 s.

Follow the measurement method at 3.2.8.

2.4.3. Total Transmission Time

2.4.3.1. Definition

The total transmission time (Tt) is the time measured at points where the power level reaches 90%.

2.4.3.2. Requirements.

The total transmission time (Tt) must be within the following limits:

- Short pulse: from 435.6 ms to 444.4 ms;

- Long pulse: from 514.8 ms to 525.2 ms.

Follow the measurement method at 3.2.9.

2.4.4. Bit Rate

2.4.4.1. Definition

The bit rate (fb) is the number of bits transmitted per second. The unit of measurement for the bit rate is bps.

2.4.4.2. Requirements

The bit rate (fb) must be within the range of 396 bps to 404 bps.

Follow the measurement method at 3.2.10.

2.4.5. Unmodulated Carrier Portion

2.4.5.1. Definition

2.4.5.1. Definitions

Part carrier wave unmodulated (T1) is the period of time between the moment when 90% of the transmission power (0.9 PN) is reached and the moment when modulated data transmission begins.

2.4.5.2. Requirements

The unmodulated carrier wave part must be within the range: from 158.4 ms to 161.6 ms. Follow the measurement method at 3.2.11.

2.4.6. Digital signal part

2.4.6.1. Definition

The digital signal part is the modulated signal transmission containing encoded bits.

2.4.6.2. Requirements

Short signal: A 112-bit transmission signal for short digital signals within 280 ms with relative tolerance ± 1%, at a bit rate of 400 bps with relative tolerance ± 1%.

Long signal: A 144-bit transmission signal for long digital signals within 360 ms with relative tolerance ± 1%, at a bit rate of 400 bps with relative tolerance ± 1%.

Follow the measurement method at 3.2.12.

2.5. PLB Beacon Coding

2.5.1. Basic structure

Each activated PLB buoy will transmit an emergency alert signal containing a unique identification code of the buoy. This identification code contains necessary information including: type of buoy; nationality and user identification encoded by the manufacturer or distributor. There are two types of signals transmitted by the PLB buoy: short signal and long signal, the selection of the signal type depends on the protocol encoding method of the buoy signal.

2.5.1.1. Short signal

With a length of 112 bits, structured as follows:

Figure 6. Data fields in the short signal format

2.5.1.2 Long signal

With a length of 144 bits, structured as follows:

Figure 7. Data fields in the long signal format

These bits are divided into five groups:

(1) Transmitting the first 24 bits, positions 1 to 24, are system bits and are used for bit synchronization and frame synchronization. 15 bits are reserved for bit synchronization (from bit 1 to bit 15) and 9 bits for frame synchronization (from bit 16 to bit 24). Among them, bits 1 to 15 are preset as "1", and frame synchronization bits from bit 16 to bit 24 are set as 000101111 (except in self-test mode). This signal allows the receiver to detect incoming signals, process, and determine the first bits of the buoy signal. In self-test mode, the frame synchronization bit group is set as 011010000 to ensure that satellites and ground equipment will not process this signal.

(2) The next 61 bits, positions 25 to 85, are data bits. This data bit group is considered the first protected data field (PDF-1). The first data bit (position 25) determines whether the signal is short or long: "0" = short signal, "1" = long signal.

(3) The following 21 bits (positions 86 to 106) are error correction codes (BCH) (82, 61). This bit group is considered the first error correction code field (BCH-1). This error correction code is shortened from a three-error-correcting BCH code (127, 106). This error correction code can detect and correct up to three bit errors in 82 bits (PDF-1 + BCH-1). The combination of PDF-1 and BCH-1 is considered the first protected field.

(4) The next group consists of data bits and this group depends on the signal format:

a) Short signal: The last 6 bits of the short signal at positions 107 to 112, these data bits are unprotected. This data bit group is considered the unprotected data field.

b) Long signal: The next 26 bits of the long signal at positions 107 to 132. This bit group is considered the second protected data field (PDF-2).

(5) The last 12 bits of the long signal at positions 133 to 144 are error correction codes BCH (38, 26). This bit group is considered the second error correction code field (BCH-2). This error correction code is shortened from a two-error-correcting BCH code (63, 51). This error correction code can detect and correct up to two bit errors in 38 bits (PDF-2 + BCH-2). The combination of PDF-2 and BCH-2 is considered the second protected field.

2.5.2. Encoding method

The encoding method is described in detail in Appendix B.

2.6. Power Supply Requirements

2.6.1. Battery requirements

The battery expiration date is calculated from the production date of the battery plus half the maximum useful operating life of the battery. The expiration date must be clearly marked.

The useful operating life of the battery is defined as the period after the production date during which the battery still meets the power supply requirements for the PLB buoy.

To determine the useful operating life of the battery, the following losses under temperature conditions of +20°C ±5°C must be taken into account:

- Self-testing at a frequency of once a month;

- Battery self-discharge;

- Losses in standby mode (if applicable).

2.6.2. Safety measures

Do not reverse the polarity of the battery.

The battery must not leak harmful substances or corrosive materials inside or outside the PLB buoy under the following conditions:

- During or after storage at temperatures between -55°C and +75°C;

- While discharging the battery completely or partially at any speed, including external short circuit;

- After complete or partial discharge of the battery.

The battery must not pose a danger to personnel handling, using, or manufacturing it when transported, stored, and installed according to specified conditions.

2.6.3. Battery capacity

2.6.3.1. Definition

Battery capacity is the ability of the internal power source to provide sufficient power for continuous device operation over a defined period of time.

2.6.3.2. Requirements

The PLB buoy must comply with the output power, short-term frequency stability, medium-term frequency stability, and PLB buoy encoding requirements for 24 hours.

Follow the measurement method at 3.2.13.

2.7. Radiated Power

2.7.1. Antenna characteristics

2.7.1.1. Definition

Antenna characteristics are determined with elevation angles greater than 5° and less than 60°.

2.7.1.2. Requirements

The antenna has the following characteristics:

- Type: hemispherical;

- Polarization: right circular polarization or linear polarization;

- Gain (perpendicular to the plane): from -3 dBi to +4 dBi;

- Gain variation (azimuth angle): < 3 dB;

- Antenna voltage standing wave ratio: ≤ 1.5 : 1.

Follow the measurement method at 3.2.14.

2.7.2. Radiated power

2.7.2.1. Definition

Equivalent isotropic radiated power (e.i.r.p) is the equivalent isotropically radiated power.

2.7.2.2. Requirements

The radiated power must be within the range from 32 dBm to 43 dBm at least 90% of measurement points.

Follow the measurement method at 3.2.15.

2.8. Homing Device

2.8.1. General requirements

2.8.1.1. Type of emission

The radio transmission signal shall be a double-sideband full-carrier modulated signal (A3X).

2.8.1.2. Modulation frequency

The subcarrier sweeps from high to low between 1600 Hz and 300 Hz over a bandwidth not less than 700 Hz.

2.8.1.3. Transmitter operating cycle

The beacon transmitter must operate continuously in cycles and may only be interrupted for a maximum of 2 seconds when transmitting signals on the 406.0 MHz to 406.1 MHz band. The PLB buoy may also optionally transmit identification letters in Morse code immediately following each stop to transmit the 406.0 MHz to 406.1 MHz signal.

2.8.1.4. Repeat sweep rate

The repeat sweep rate of the transmitter is: 2 Hz to 4 Hz.

2.8.2. Frequency error

2.8.2.1. Definition

Frequency error is the difference between the measured carrier frequency and its nominal value.

2.8.2.2. Requirements

The carrier frequency is: 121.5 MHz ± 50 ppm.

Follow the measurement method at 3.2.16.

2.8.3. Modulation duty cycle

2.8.3.1. Definition

The modulation duty cycle is the ratio of the time interval of positive peak modulation to the time interval of the instantaneous subcarrier frequency occurring at half-amplitude points on the envelope of the modulated signal, observed using the following formula.

Modulation duty cycle =         (1)

Where:

T₁: half positive cycle time of the subcarrier modulation measured at half-amplitude points of the modulation process.

T₂: period of the basic subcarrier frequency.

2.8.3.2. Requirements

The modulation duty cycle must be between: 33% and 55%.

Follow the measurement method at 3.2.17.

2.8.4. Modulation index

2.8.4.1. Definition

The modulation index is defined according to the aspect between the maximum amplitude and the minimum amplitude of the modulated envelope using the formula.

Modulation index =            (2)

Where:

A: maximum amplitude value of the modulated envelope.

B: minimum amplitude value of the modulated envelope.

2.8.4.2. Requirements

The modulation index must be within the range: 0.85 and 1.

Follow the measurement method at 3.2.18.

2.8.5. Peak equivalent isotropic radiated power

2.8.5.1. Definition

Equivalent isotropic radiated power (e.i.r.p) is the total power supplied to the antenna and related to the direction of the isotropic antenna. Peak equivalent isotropic radiated power (Pe.i.r.p) defines the power contained within the peak edge of the modulation process.

For the PLB buoy, the radiation field must be vertically polarized.

2.8.5.2. Requirements

The average value of 12 measurements must be greater than 25 mW and the maximum value must be less than 100 mW.

Follow the measurement method at 3.2.19.

2.8.6. Spurious emissions

2.8.6.1. Definition

Spurious emissions are emissions on one or more frequencies outside the necessary bandwidth and the emission level can be reduced without affecting the corresponding information transmission. Spurious emissions include harmonic emissions, parasitic emissions, intermodulation products, and frequency conversion products but do not include out-of-band emissions.

2.8.6.2. Requirements

The power of any spurious emission component at any frequency: ≤ 25 µW. Follow the measurement method at 3.2.20.

3. MEASUREMENT METHODS

3.3. Essential Parameters for the Wireless Part

3.1.1. General requirements

The requirements of this standard must be met 15 minutes after activation of the PLB buoy.

The manufacturer must provide sufficient information to establish, test, and operate the equipment during testing.

If the equipment contains any additional or auxiliary devices, they must operate throughout the testing period and in the maximum battery power consumption mode. During testing, all audio and visual indicators must function.

3.1.2. Quality testing

For the purposes of this document, the term "quality testing" will be used to mean testing the ability of the PLB buoy to operate in self-test mode and decode the messages transmitted by the PLB buoy.

3.1.3. Preparation of the PLB buoy for testing

When testing, the PLB buoy must be programmed to transmit encoded data bursts according to the appropriate protocol. The navigation equipment must be prepared to transmit during testing. Avoid transmitting distress signals on distress and safety frequencies by frequency offset or test encoding.

The manufacturer must provide a PLB buoy with an antenna port that can be connected to the testing equipment via coaxial cable. This connection must be waterproof and withstand all environmental conditions. The antenna port configuration can be prepared by the manufacturer before testing.

In cases where the waterproof connector cannot fit due to the shape or size of the PLB buoy, manufacturers may provide two sets for testing. One set is the standard product, the other is connected to the coaxial cable but may not withstand all environmental conditions. Both sets must undergo all environmental tests except for liquid immersion tests, which are only performed on the standard product set.

3.1.4. Testing sequence

All measurements must be carried out in the order specified in this standard and may be combined with tests as described in the Cospas-Sarsat documentation C/S T.001 and C/S T.007.

All measurements must be conducted on a single unit and prepared according to 3.1.3.

3.1.5. Test source

The equipment must use internal battery power when conducting tests and quality testing.

Use three batteries when conducting conformity tests.

3.1.6. Test location

The test location must be free of reflective objects such as trees and metal objects. There should be no reflective objects within the ellipse range as shown in Figure C.1, Appendix C.

The terrain outside the test location must be flat. Any conductors within the ellipse area must be smaller than 7 cm. Prepare a metallic floor or wire mesh covering at least the major and minor axes of the ellipse as shown in Figure C.1. All wires and cables must be laid under the floor. The antenna cable must be extended 1.5 meters beyond both axes along the major axis before going down to the floor.

During measurement, no person shall stand within a range of 6 meters from the PLB. The measurement report must detail the measurement environment.

The measurement position may be surrounded by materials such as fiberglass, plastic, wood, or fabric.

3.1.7. Measurement Setup

The measurement setup as shown in Figure C.2, Appendix C.

The antenna characteristics of the PLB buoy will be measured at the measurement position as specified in 3.1.6.

Place the measuring antenna horizontally, 3 meters away from the PLB buoy to measure the emission field strength. To ensure all azimuth angles are measured, place the PLB buoy on rotatable surface B that can rotate 360°, and 0.75 meters above surface A. For elevation angle measurements as required, the measuring antenna must be placed vertically. The PLB buoy must be equipped with new batteries and the testing conducted at ambient temperature.

3.1.8. Calibration of the Measuring Receiver

The measuring receiver (which may be a field strength meter or spectrum analyzer) is calibrated as follows:

a) Connect the equipment as shown in Figure C.2. Install the PLB buoy as specified in 3.1.7.

b) Turn on the PLB buoy to emit normally. Set the receiver bandwidth to measure the transmission power. This bandwidth is used during the antenna measurement process. Adjust the receiver to obtain the maximum received signal. Position the measuring antenna in the plane (vertical or horizontal) where the received signal is strongest. Rotate the PLB buoy antenna and determine the direction with average emission field strength. Record the reception level;

c) Disconnect the measuring antenna and supply standard RF power to the receiver through the measuring antenna cable.

Adjust the signal source to achieve the same reception level as in part b);

d) Disconnect the standard RF power from the measuring antenna cable and measure the RF output using a power meter;

e) Reconnect the standard RF power to the measuring antenna cable and adjust the receiver calibration factor.

3.1.9. Measuring Antenna

The emission field of the PLB buoy antenna is detected and measured using a dual-polarized antenna. The dual-polarized antenna is placed 3 meters away from the PLB buoy antenna and mounted on a vertical support column that can change the height of the measuring antenna from 1.3 meters to 4.3 meters (i.e., from 10° to 15° relative to the horizontal plane B set at the standard height X = 0.75 meters, Figure C.2). The measuring antenna must be raised to an elevation angle calculated according to the following formula:

h = 3 tanθ and H = h + X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            &

Where:

X: standard height (0.75 m)

h: height of the antenna measured relative to the standard height X

θ: elevation angle relative to surface B (at the standard height X)

H: height of the antenna measured relative to floor A

NOTE: The midpoint of the dual-pole antenna is used to determine its height.

When the measuring antenna is raised vertically, the distance (R) between the PLB antenna and the measuring antenna increases. The distance (R) is a function of the elevation angle (θ) and is calculated using the following formula:

It is necessary to know the antenna factor (AF) of the measuring antenna at the frequency band from 406.0 MHz to 406.1 MHz. This factor is usually provided by the manufacturer of the dual-pole antenna. It is used to convert voltage readings into electromagnetic field strength.

                   (4)

Since the value of AF depends on the direction of wave propagation relative to the orientation of the receiving antenna, the dual-pole antenna must always be perpendicular to the direction of wave propagation. To reduce measurement errors, use the directional correction factor for the measuring antenna (Figure C.3) if the measuring antenna is not perpendicular to the direction of wave propagation (Figure C.4). For dual-pole antennas, the antenna correction factor is calculated as follows:

AF: antenna factor of the measuring antenna at the frequency band from 406.0 MHz to 406.1 MHz;

                  (5)

Where:

θ: elevation angle;

P: correction factor for the dual-pole antenna.

NOTE: The correction factor (P) = 1 when the measuring antenna is perpendicular to the direction of wave propagation. Therefore, P = 1 for any elevation angle when the measuring antenna is horizontally polarized. The correction factor only applies to vertically polarized measurements.

3.1.10. Normal measurement conditions

3.1.10. Conditions for routine inspection and testing

Temperature and humidity conditions:

- Temperature: +15°C to +35°C

- Relative humidity: 20% to 75%

3.1.11. Limit testing conditions

The measurements shall be carried out according to the procedure in 3.1.12 at the upper and lower limit temperatures as follows:

- For type 1 PLB buoy: -40°C and +55°C

- For type 2 PLB buoy: -20°C and +55°C

When testing the automatic release mechanism at limit temperatures, the upper and lower limit temperatures are -30°C and +65°C.

3.1.12. Procedure for limit temperature testing

The equipment must be turned off during the temperature stabilization period.

Prior to performing the measurements, the equipment must reach thermal equilibrium in the test chamber and be powered on for 15 minutes.

3.1.13. Measurement uncertainty

Table 1. Absolute measurement uncertainty for maximum values

3.2. Measurement Method

3.2.1. Frequency emission measurement method

The characteristic frequency is determined from 18 carrier frequency measurements of the unmodulated signal, performed under limit conditions (3.1.11 and 3.1.12) during time S1 (Figure 8) of 18 consecutive transmissions as follows:

                   (6)

Where:

P₀: characteristic frequency;

P_{c, j}: carrier frequency of the unmodulated signal at the jth measurement.

Figure 8. Measurement times

- Pulse S₁ starts 12 ms after the start of the unmodulated carrier wave.

- Pulse S₂ starts at bit 23.

- Pulse S₃ starts 15 ms after the end of S₂.

3.2.2. Output power measurement method

The output power of the transmitter is measured at the transmitter's output under normal testing conditions and the highest and lowest values are recorded.

3.2.3. False transmitter emission measurement method

The measurement is conducted with the PLB buoy operating at a 50 Ω impedance. The bandwidth of the measuring instrument will be ≤ 100 Hz. This measurement is performed on a spectrum analyzer in the maximum mode over a sufficient period of time to observe the entire frequency response curve.

3.2.4. Data encoding measurement method

Feed the modulated RF signal to the input of a linear demodulator and a decoder.

The limits of phase φ₁  and φ₂  in Figure 2 are measured under limit testing conditions without considering instantaneous values.

3.2.5. Modulation measurement method

Use an oscilloscope to check the modulation waveform, modulation index, modulation rise time (t_{||| R}) of the modulated waveform are the times measured between points 0.9 of the phase transition peaks (Figure 3)._F), and modulation symmetry of the two-phase modulated signal.

Measure the modulation characteristics within the first 15 bits of the modulated signal transmission, and determine the average values based on positive and negative phase changes. It is recommended to display and observe until the end of the modulated signal transmission.

3.2.6. Standing Wave Ratio (VSWR) measurement method

Operate the transmitter in an open circuit state for a minimum of 5 minutes, then in a short circuit state for a minimum of 5 minutes. Subsequently, operate the transmitter with a load having a VSWR ratio of 3:1 (pure resistance R < 50 Ω) for a period during which the following parameters are measured:

- Transmitter nominal frequency;

- Digital message content;

- Modulation parameters.

These measurements are performed at the highest, lowest, and ambient temperatures.

3.2.7. Continuous transmission duration measurement method

The maximum continuous transmission duration is tested by continuously transmitting from the PLB buoy. However, if the PLB buoy manufacturer provides documentation proving compliance with requirements, this measurement need not be performed.

3.2.8. Repeat cycle measurement method

The repeat cycle is measured from the point where the carrier wave output power reaches 90% of the transmission power of the current transmission to the point where it reaches 90% of the transmission power of the next transmission. This measurement is performed over 18 consecutive transmissions. The difference between the longest and shortest repeat cycles exceeds 4 seconds. The average repeat cycles are 50 s ± 1,5 s. The standard deviation of the 18 measured TR values ranges from 0,5 to 2,0 s. The observed minimum TR value is between 47,5 and 48,0 s, the observed maximum TR value is between 52,0 and 52,5 s.

3.2.9. Total transmission time measurement method

Measure the total transmission time at the points where 90% power is reached in each transmission until the end of the transmission process (power drops below 90% of the transmission power). This measurement is performed over 18 consecutive transmissions.

3.2.10. Bit rate measurement method

The bit rate is measured on at least the first 15 bits of each transmission. Perform the measurement over 18 consecutive transmissions.

3.2.11. Unmodulated carrier wave portion measurement method

The unmodulated carrier wave segment is measured from the moment when the output carrier wave power reaches 90% of the transmission power to the start of the digital pulse segment. This measurement is conducted over 18 consecutive transmissions.

3.2.12. Method for measuring the digital pulse segment

The digital pulse segment is measured from the start of the digital pulse emission until the end of the emission process (when the power drops below 90% of the transmission power). This measurement is conducted over 18 consecutive transmissions.

3.2.13. Method for measuring battery capacity

Use a new battery, activate the PLB buoy (at ambient temperature) for a period specified by the manufacturer. This period corresponds to the capacity loss due to self-testing and self-discharge during the useful operational time of the battery. The manufacturer must indicate the method used to determine this period.

Place the PLB buoy in a room with normal temperature. Then reduce the temperature and maintain it at -40°C ± 3°C for type 1 PLB buoy or -30°C ± 3°C for type 2 PLB buoy for 10 hours.

Any temperature control device installed in the PLB buoy must be turned on, and type 2 PLB buoys in the room must be heated up to -20°C ± 3°C. This process must be completed within 20 minutes.

After 30 minutes, activate the PLB buoy and maintain continuous operation for 24 hours. The temperature of the test chamber must be kept stable throughout the 24-hour period.

3.2.14. Method for measuring antenna characteristics

The antenna gain coefficient is calculated for each angular coordinate according to the formula:

                (7)

Where:

e.i.r.p: equivalent isotropic radiated power

"5. The pre-tax weighted average cost of capital i (%) is determined according to the formula below:_{organize credit institutions, foreign bank branches are responsible for organizing the implementation of this Circular.}: power supplied to the PLB buoy antenna

G_{ANNEX I.A[31]}: ratio of the PLB buoy antenna gain coefficient to that of an isotropic antenna

Data analysis (V_{BB 1.1}for each specific service package in the service provision contract between the ISP and the customer._h) obtained during the measurement at 3.2.15 must allow the determination of whether the PLB buoy antenna polarization is linear or circular.

If the measured induced voltage (V_{BB 1.1}for each specific service package in the service provision contract between the ISP and the customer._h) differs by at least 10 dB for each different angular coordinate (azimuth angle, elevation angle), the polarization is linear. The polarization will be vertical or horizontal if Vv or Vh is larger.

If the measured induced voltage (V_{BB 1.1}for each specific service package in the service provision contract between the ISP and the customer._h) differs within 10 dB, the PLB buoy antenna has circular polarization.

Compare the received signals using known right-hand circular polarized antennas and left-hand circular polarized antennas while the PLB buoy is transmitting. The measurement result with the higher received signal strength will determine the polarization direction.

3.2.15. Method for measuring radiated power

The PLB buoy transmits normally using a new battery. Transfer the signal from the measurement antenna to a spectrum analyzer or field strength meter. Rotate the PLB buoy 360° with at least 12 equal steps of 30° ± 3° and perform measurements.

To measure total e.i.r.p, the measurement antenna must have linear polarization and be positioned in two orientations to align with both vertical and horizontal components of the transmitted signal.

Then place the measurement antenna at elevation angles of 10°, 20°, 30°, 40°, and 50° (±3°) with azimuth angles from 0° to 360° in 30° increments and measure the induced voltage for each polarization at these 60 positions.

Record the values of V_h and V_{BB 1.1} at each measurement position.

The following steps are performed for each measured voltage value and the results are recorded.

Step 1: Calculate the total induced voltage Vrec in dBV using the formula:

            (8)

Where:

V_{BB 1.1} and V_h: measured voltages (V) when the measurement antenna is oriented in the vertical and horizontal planes.

Step 2: Calculate the electric field intensity E in dBV/m at the measurement antenna using the formula:

E_(dBV/m) = V_rec+ 20logAF_c + L_c                  (9)

Where:

V_rec: signal level calculated from step 1 (dBV);

AF_c: calibration parameter of the measurement antenna;

nh cơ_c: system reception loss and cable attenuation (dB).

Step 3: Calculate e.i.r.p

Calculate e.i.r.p for each angular coordinate using the formula:

                  (10)

Where:

R: distance between the PLB buoy and the dual-polarization measurement antenna;

E: electric field intensity converted in step 2 to V/m.

Measurements are carried out under normal testing conditions.

3.2.16. Method for measuring navigation equipment frequency error

Measure the carrier wave frequency using a frequency counter or spectrum analyzer under normal and limit testing conditions.

3.2.17. Method for measuring the modulation cycle duration of navigation equipment

Connect the transmitter output to a memory oscilloscope. T1 and T2 are measured at the beginning, middle, and end of the modulation cycle. The modulation cycle duration will be calculated.

3.2.18. Method for measuring the modulation index of navigation equipment

Connect the transmitter output to a memory oscilloscope. A and B are measured at the beginning, middle, and end of the modulation cycle. Then calculate the modulation index.

3.2.19. Method for measuring the peak equivalent isotropic radiated power of navigation equipment

The test site must be placed on an electromagnetic homogeneous ground surface without metallic objects, overhead wires, etc., and without unwanted signals such as radio frequency interference. The minimum distance from the PLB buoy or measurement antenna to surrounding reflective objects is 30 meters.

Signal radiation measurements must be conducted 10 meters away from the PLB buoy. At this point, a non-conductive pole with a movable collar must be installed to allow the antenna to move up or down corresponding to elevation angles from 5° to 20°.

The measurement antenna must have vertical polarization.

Note 1: The 10-meter test distance can be reduced to a minimum of 5 meters if the pole does not reach 20°.

Note 2: An enclosed soundproof test room may be used within a minimum range of 5 meters.

This testing method can only be performed under normal ambient temperature conditions and must use a PLB buoy with a battery in the on state for a minimum of 20 hours. If the test exceeds 4 hours, it must be replaced with another battery that has also been on for a minimum of 20 hours.

The PLB buoy must be placed in the center of a ground plane with a radius of (125 ± 5) cm attached below the ground (as shown in Figure 9).

When conducting tests outside an enclosed room, care must be taken not to transmit distress signals at distress frequencies and safety frequencies, for example, by using offset frequencies for transmission.

The elevation angle of the measurement antenna must be changed from 5° to 20° until the maximum signal is found. As the elevation angle changes, the measurement antenna must be directed towards the PLB buoy. The elevation angle must then be held constant throughout the test.

Then rotate the PLB buoy 12 times, increasing 30° each time along the azimuth angle. At each position, measure the peak equivalent isotropic radiated power and calculate based on the following formula:

Pe.i.r.p = Log^-1 [(P_rec : bid price after corrections and adjustments, minus any discount (if applicable) of the lowest bidder among those detailed financial evaluations;_rec + L_c + L_path)/10]          (11)

Where:

"5. The pre-tax weighted average cost of capital i (%) is determined according to the formula below:_rec: Maximum power measured at the receiver or spectrum analyzer (dBm)

G_rec: Gain of the antenna measurement (dB)

nh cơ_c: System reception cable loss (dB)

nh cơ_path: Free space propagation loss for slant range

3.2.20. Method for measuring spurious emissions of navigation equipment

Measure spurious emissions in the following frequency bands:

• From 108 MHz to 137 MHz

• From 156 MHz to 162 MHz

• From 406.0 MHz to 406.1 MHz

• From 450 MHz to 470 MHz

According to the measurement setup diagram as shown in Figure 9:

Figure 9. Measurement setup diagram for isotropic equivalent radiated power and spurious emissions

5. RESPONSIBILITIES OF ORGANIZATIONS AND INDIVIDUALS

Personal Locator Beacons (PLBs) operating on the 406.0 MHz to 406.1 MHz band within the scope regulated under 1.1 must comply with the provisions of this Standard.

5. RESPONSIBILITIES OF ORGANIZATIONS AND INDIVIDUALS

5.1. Organizations and individuals related have the responsibility to implement conformity certification and declaration of conformity for Personal Locator Beacons (PLBs) operating on the 406.0 MHz to 406.1 MHz band and are subject to inspection by state management agencies according to current regulations.

5.2. Organizations and individuals related have the responsibility to register identification codes with competent authorities of Vietnam according to the prescribed regulations.

6. IMPLEMENTATION ORGANIZATION

6.1. The Telecommunications Authority and Provincial Departments of Information and Communications are responsible for organizing guidance and implementing management of Personal Locator Beacons (PLBs) operating on the 406.0 MHz to 406.1 MHz band according to this Standard.

6.2. In case the provisions of this Standard change, supplement, or are replaced, they shall be implemented according to the new document.

 

ANNEX A

Product Name, Goods According to QCVN

Environmental testing

A.1. General Requirements

Environmental tests in this section must be conducted before other measurements and must be performed under normal measurement conditions unless otherwise specified. The PLB buoy must be in normal operating condition but not transmitting, unless otherwise specified.

Environmental tests must be carried out in sequence as specified in this standard unless otherwise specified.

A.2. Temperature test

A.2.1. Definition

This test determines the device's ability to withstand temperature to ensure electrical and mechanical performance after the test.

A.2.2. Dry heat test

A.2.2.1. Test method

Place the device in a room with normal ambient temperature. Then increase the temperature and maintain it at +70°C ± 3°C for a period of 10 hours to 16 hours.

The maximum rate of temperature rise and fall in the test chamber is 1°C/min.

After this time, the temperature control unit inside the device is turned on and the temperature in the test chamber is reduced to +55°C ± 3°C. The cooling process must be completed within 30 minutes.

Subsequently, turn on the device and maintain normal operation for 2 hours. Maintain the temperature in the test chamber at +55°C ± 3°C for 2 hours and 30 minutes. Inspect the device quality during the last 30 minutes.

At the end of the test, the test chamber must be cooled down to room temperature within at least 1 hour. The device must be placed in normal room temperature and humidity conditions for at least 3 hours before conducting further measurements.

A.2.2.2. Requirements

Quality inspection requirements must be met.

A.2.3. Low temperature test

A.2.3.1. Test method

The device must be placed in a room with normal ambient temperature. Then decrease the temperature and maintain it at -40°C ± 3°C for Type 1 PLB buoys and -30°C ± 3°C for Type 2 PLB buoys for a period of 10 hours to 16 hours.

Turn on the temperature control unit inside the device and adjust the room temperature to -20°C ± 3°C (for Type 2 PLB buoys). This process must be completed within 25 minutes ± 5 minutes.

The temperature in the room must be maintained for 2 hours.

The device is inspected for quality during the last 30 minutes of the testing process. At the end of the test, the test chamber must be cooled down to room temperature within at least 1 hour. The device must be placed in normal room temperature and humidity conditions for at least 3 hours or until the humidity is evenly distributed before conducting further measurements.

During testing, the device must operate normally.

A.2.3.2. Requirements

Quality inspection requirements must be met.

A.3. Vibration test

A.3.1. Definition

This test determines the device's ability to withstand vibration to ensure electrical and mechanical performance.

A.3.2. Test method

The device is mounted on a vibration table.

Minimize or avoid effects on the device's operational capability due to electromagnetic fields from the vibration mass when the device is vibrating.

Vibrate the device for at least 15 minutes to cover each octave of frequency, the device must withstand sinusoidal vibration along the vertical axis at all frequencies between:

5 Hz and 12.5 Hz with an amplitude of ± 1.6 mm with a relative tolerance of ± 10%

12.5 Hz and 25 Hz with an amplitude of ± 0.38 mm with a relative tolerance of ± 10%

25 Hz and 50 Hz with an amplitude of ± 0.10 mm with a relative tolerance of ± 10%

The frequency sweep rate must be low enough to allow detection of resonance in parts of the device.

Resonance detection must be performed during vibration testing. If resonance is found in any part, the device must be tested for vibration resistance at that resonant frequency for at least 2 hours. Testing must be repeated with the same level of vibration in the perpendicular direction in the horizontal plane.

Quality inspection of the PLB buoy must be conducted both before and after vibration testing. At the end of the test, the device must be examined for mechanical failures.

A.3.3. Requirements

The PLB buoy must not automatically activate during the test.

Quality inspection requirements must be met. There should be no visible mechanical failures.

A.4. Impact test

A.4.1. Definition

This test determines the device's ability to withstand impact to ensure electrical and mechanical performance.

A.4.2. Test method

The PLB buoy is securely attached to the test device and subjected to impact testing as follows:

- Peak acceleration: 98 m/s²

- Pulse width: 16 ms

- Waveform: Half-sine wave

- Number of impacts: 4000

Conduct impact testing three times; each corresponding to the PLB buoy attached to each axis among the three axes. After completing the impact test, conduct external mechanical inspection and quality inspection.

A.4.3. Requirements

The PLB buoy must not automatically activate during the test.

Quality inspection requirements must be met. There should be no visible mechanical failures.

A.5. Corrosion test

This test may not be necessary if the manufacturer can demonstrate that the components and materials used in the device are capable of resisting corrosion effects on the device's electrical and mechanical performance.

A.5.1. Definition

This test determines the anti-corrosion capability of the equipment to ensure electrical and mechanical performance.

A.5.2. Test Method

The equipment must be turned off throughout the entire testing process. Prior to spraying the salt solution onto the equipment, the equipment must be placed in an environment with a temperature of 35°C ± 2°C for at least 2 hours. The ambient temperature is maintained at 35°C, and the salt solution is continuously replenished and kept saturated for 48 hours. Use a fog spray device in the room where the test equipment is located, with the salt solution having components as listed in Table A.1.

Table A.1. Composition of Salt Solution

Additionally, a 5% NaCl solution may be used. The salt used in the test must be high-quality NaCl (0.1% iodine and 0.3% total impurities).

The solution is prepared by dissolving 5 parts ± 1 part by weight of salt in 95 parts by weight of distilled water or demineralized water.

The pH of the solution must be between 6.5 and 7.2 at a temperature of 20°C ± 2°C. Maintain the pH within this range by adding HCl or NaOH to adjust the pH.

The fog spray devices must ensure that there are no corrosive components in the salt solution.

After spraying the salt solution, the equipment must be dried at room temperature of 20°C ± 5°C for 24 hours before the next cycle of 12 hours of salt spray at 35°C. After completing this test and drying the equipment at room temperature for 12 hours, the equipment must be visually inspected. The self-test of the PLB buoy must also be performed.

A.5.3. Requirements

Metal parts, coatings, materials, or other parts shall not show signs of deterioration or corrosion visible to the naked eye.

In the case of sealed installation, the equipment must not show signs of moisture ingress.

Quality inspection requirements must be met. There should be no visible mechanical failures.

A.6. Drop Test

A.6.1. Definition

This test determines the ability of the equipment to withstand drops to ensure electrical and mechanical performance.

A.6.2. Test Method

The PLB buoy must be turned off during the drop test.

The PLB buoy must be kept at the minimum storage temperature for 2 hours. Then place the PLB buoy at -40°C for 2 hours. The drop test must be completed within 5 minutes.

The height of the lowest part of the PLB buoy from the test surface at the moment of release must be (1000 ± 10) mm. The PLB buoy must be dropped six times onto the test surface. Each drop corresponds to each axis of the PLB buoy with its surface facing down. The antenna may be securely fastened in its normal storage position (if provided) during the drop test. If the PLB buoy is supplied with a bag or similar package that is not fixed, it must be removed before performing the drop test.

The test surface must contain a solid wooden board with a thickness of at least 150 mm and a weight of 30 kg or more placed on a concrete floor.

A.6.3. Requirements

The PLB buoy must not activate during the test.

After completing the drop test, perform mechanical inspection inside and out, and quality inspection. The internal mechanical inspection can be postponed after the thermal shock test and immersion test.

A.7. Thermal Shock Test

A.7.1. Definition

This test determines the thermal shock resistance of the equipment to ensure electrical and mechanical performance.

A.7.2. Test Method

The equipment must be placed in an air environment at +65°C ± 3°C for 1 hour. Then immerse the equipment in water at +20°C ± 3°C to a depth of 10 cm (measured from the highest point of the PLB buoy to the water surface) for 1 hour.

At the end of the test, perform the self-test procedure.

A.7.3. Requirements

Quality inspection requirements must be met. There must be no visible damage or water ingress.

A.8. Immersion Test

A.8.1. Definition

This test determines the water resistance capability of the equipment to ensure electrical and mechanical performance.

A.8.2. Test Method

The equipment must withstand a hydrostatic pressure of 10 kPa (equivalent to a depth of 1 meter) for 5 minutes. At the end of the test, perform the self-test procedure.

A.8.3. Requirements

Quality inspection requirements must be met. There must be no visible damage or water ingress.

A.9. Buoyancy Test

A.9.1. Definition

The buoyancy test applies only to type 1 PLB buoys.

Buoyancy is calculated as a percentage of the ratio of buoyant force to gravity.

A.9.2. Test Method

Immerse the PLB buoy in water.

One of the following two methods may be used:

- Measure the buoyant force while the entire PLB buoy is submerged in water. Divide the buoyant force by the measured weight and record the result, or

- Calculate the buoyancy by dividing the volume above the waterline by the volume below the waterline. Record the result.

A.9.3. Requirements

Buoyancy ≥ 5%.

 

ANNEX B

Product Name, Goods According to QCVN

Coding Method

B.1. Identification of Encoding Protocols

PLBs are encoded in various ways using different protocols. The encoding protocols and identification numbers are provided by the national beacon registry manager. These protocols are distinguished from each other through format flags, protocol flags, and protocol codes used in the telegrams.

B.1.1. Format Flag, Protocol Flag, and Country Code

- The bit positions in the format flag, protocol flag, and country code are consistent across all protocols. They are defined in PDF-1 of short and long telegrams as follows:

Bit 25 is used for: Format Flag (F)

Bit 26 is used for: Protocol Flag (P)

Bits 27 to 36 are used for: Country Code

- The format flag (bit 25) is encoded as follows for short or long telegrams:

F = 0 Short format

F = 1 Long format

- The protocol flag (bit 26) indicates the type of protocol used to determine the structure of the encoded data as follows:

P = 0 Standard positioning protocols, national positioning protocols.

P = 1 User protocols or user positioning protocols.

- The country code is three decimal digits represented in binary from bits 27 to 36. The country code is based on the Maritime Identification Digit (MID) according to ITU. Vietnam's country code is 574.

B.1.2. Protocol Code

- Protocol Code:

Each encoded protocol is identified by a protocol code as follows:

+ Three-bit code from bit 37 to bit 39 for user protocols or user positioning protocols.

+ Four-bit code from bit 37 to bit 40 for standard positioning protocols, national positioning protocols, service line response positioning protocol, and test positioning protocol.

Table B.1 shows the combinations of format flags and protocol flags to identify each encoded protocol type.

Table B.1. Combination of protocol flags and format flags

- The PLB beacon will be encoded according to one of the two groups of protocols below:

+ User protocol (including serial user protocol, test user protocol, orbit protocol, and national user protocol).

+ Positioning protocol (including user positioning protocol, standard positioning protocol, national positioning protocol, service line response positioning protocol, and test positioning protocol).

Table B.2. Assignment table of user protocol codes and user positioning protocol codes for PLB beacons

 

Table B.3. Assignment table of standard positioning protocol codes, national positioning protocol codes, service line response positioning protocol codes, and test positioning protocol codes for PLB beacons

B.2. User protocol

The PLB beacon in the user protocol will be encoded according to the serial user protocol, test user protocol, orbit protocol, and national user protocol.

B.2.1. Structure of the serial user protocol

- The serial user protocol has the following structure:

Bit 25 is used for: Format flag (= 0);

Bit 26 is used for: Protocol flag (= 1);

Bits 27 to 36 are used for: Country code;

Bits 37 to 39 are used for: Serial user protocol code (= 011);

Bits 40 to 42 are used for: Type of PLB beacon encoded with serial number (= 110);

Bit 43 is used for: Flag bit for C/S type approval certificate number;

Bits 44 to 63 are used for: Serial number;

Bits 64 to 73 are used for: All zeros or country of use;

Bits 74 to 83 are used for: C/S type approval certificate number or country of use;

Bits 84 to 85 are used for: Types of auxiliary radio location devices;

- Bits 40 to 83 are used to encode identification data, together with the protocol flag, country code, beacon protocol code, and bits 84 to 85 will create a unique identification number for each beacon, i.e., 15 Hex ID.

- Bit 43 is the C/S type approval certificate number flag bit. If bit 43 is set to 1:

+ Bits 64 to 73 should be all zeros or assigned to the country of use and controlled.

+ Bits 74 to 83 are encoded with the C/S type approval certificate number. The C/S type approval certificate number is the certification number of each type of beacon approved by the Cospas-Sarsat organization.

If bit 43 is set to 0:

+ Bits 64 to 83 are for the country of use and control.

- Bits 44 to 63 specify the serial number identification range from 0 to 1048575 (i.e., 2^20-1) represented in binary.

- Bits 84 to 85 are used to indicate the type of auxiliary radio location device and are used as follows:

00: No auxiliary radio location device

01: 121.5 MHz

10: Marine search and rescue radar transponder 9 GHz (SART)

11: Other types of auxiliary radio location devices

If other types of auxiliary radio location devices use the 121.5 MHz homing frequency, code 01 will be used.

B.2.2. Test user protocol

The test user protocol is used for explanation, approval, national testing, training... The Cospas-Sarsat Mission Control Center (MCC) transmits messages encoded with this protocol unless there is a directive from the competent authority for national testing.

The test user protocol has the following structure:

- Bit 25 is used for: Format flag (short message = 0, long message = 1)

- Bit 26 is used for: Protocol flag (= 1)

- Bits 27 to 36 are used for: Country code

- Bits 37 to 39 are used for: Test user protocol code (= 111)

- Bits 40 to 85 are used for: Country of use

B.2.3. Orbit protocol

The orbit protocol is used for satellite beacons of the system. Therefore, it is not described in this standard.

B.2.4. National user protocol

The national user protocol is a special encoding format with some data fields indicating "country of use," defined and reviewed by the government of each country regarding encoding in the country code field.

The national user protocol can be either a short message or a long message indicated by the format flag (bit 25). The BCH codes must be encoded at bits 86 to 106 and at bits 133 to 144 if sending a long message.

The national user protocol has the following structure:

- Bit 25 is used for: Format flag (short message = 0, long message = 1)

- Bit 26 is used for: Protocol flag (= 1)

- Bits 27 to 36 are used for: Country code

- Bits 37 to 39 are used for: National user protocol code (= 100)

- Bits 40 to 85 are used for: Country of use

- Bits 86 to 106 are used for: 21-bit BCH code

- Bits 107 to 112 are used for: Country of use

- Bits 113 to 132 are used for: Country of use (long message)

- Bits 133 to 144 are used for: 12-bit BCH code (long message)

When an alarm is triggered, the content of the message from bit 1 to bit 106 must be fixed, bits 107 onwards allow changes according to the rule, the 12-bit BCH code is recalculated, and such changes must not exceed once within 20 minutes.

It should be noted that when the alert message is encoded with the user protocol according to the country through the Cospas-Sarsat system, only Hex data is available, and the content of the message can only be interpreted by the national manager.

B.2.5. Unprotected Data Field

The unprotected data field includes bits 107 to 112, which are encoded with emergency codes or country-specific user data represented as follows:

- When the emergency code or country-specific user data is not implemented or data is not entered, the following default encoding is used:

+ Bits 107 to 112 are set (= 0)

- Bit 107 is a flag bit that must automatically be set to value = 1 if emergency code data exists in bits 109 to 112.

+ Bit 108 specifies the activation method associated with the beacon:

+ Setting bit 108 = 0 indicates a manually activated beacon type (Mandatory for PLB beacons)

+ PLB beacon encryption protocols use non-maritime emergency codes. Non-maritime emergency codes are optional features integrated into the beacon allowing users to enter data in the emergency code field (bits 109 to 112). If data is entered in bits 109 to 112, bit 107 must automatically be set to 1 and bits 109 to 112 must be set to appropriate non-maritime emergency codes as shown in Table B.4.

Table B.4. Non-Maritime Emergency Codes

- When bit 107 is set (= 0), the codes (0001) to (1111) of bits 109 to 112 are assigned according to the country's usage and must comply with the protocol of the national manager.

B.3. Positioning Protocols

The PLB beacon message in positioning protocols includes buoy position data and buoy identification data encoded in the transmitted digital message from the distress beacon.

B.3.1. Definitions in Positioning Protocols and Default Values in Position Data

- Position Data:

All location information encoded is degrees, minutes, and seconds according to latitude or longitude. Longitude and latitude data are rounded to the available resolution. All rounding up operations follow standard rounding conventions. For example, with a resolution of 4, values from 0.000 to 1.999 will be rounded to 0 and values from 2.000 to 3.999 will be rounded to 4.

In the user positioning protocol, the position encoded in PDF-2 should be as close to the actual position as possible.

In the standard positioning protocol, national positioning protocol, and service line response positioning protocol, the position is encoded as follows. The initial raw position encoded at PDF-1 is selected to be as close as possible to the actual position. The position offset encoded at PDF-2 is calculated entirely by subtracting the actual position from the raw position encoded in PDF-1.

When a position is encoded in PDF-1, higher-resolution information provided in PDF-2 is a latitude and longitude offset related to the position in PDF-1.

The longitude and latitude values contained in PDF-1 are positive numbers regardless of their direction. The offset is applied by adding or subtracting the offset in PDF-2. For example:

Longitude 100°E + offset 30′ = Longitude 100°30′E

Longitude 100°W + offset 30′ = Longitude 100°30′W

Longitude 100°W - offset 30′ = Longitude 99°30′W

- Additional Data:

The following additional data is provided in positioning protocols, in addition to mandatory identification data and available position data.

+ Source of Position Data:

This information is encoded in bit 107 in the user positioning protocol or bit 111 in the standard positioning protocol and national positioning protocol with the following understanding:

"0" = Encoded position data is provided by an external positioning device.

"1" = Encoded position data is provided by an internal positioning device.

+ Radio Auxiliary Positioning Device Code (Navigation Device):

Information about the 121.5 MHz navigation device is encoded in bit 112 in the standard positioning protocol and national positioning protocol:

"1" = Indicates a 121.5 MHz radio auxiliary positioning device.

"0" = Indicates another or no radio auxiliary positioning device.

And in bits 84 to 85 in the user positioning protocol is encoded as follows:

"00" = No radio auxiliary positioning device.

"01" = 121.5 MHz radio auxiliary positioning device.

"10" = Maritime 9 GHz positioning (SART).

"11" = Other radio auxiliary positioning device.

- Default Values in Position Data:

Default values must be used in all encoded position data fields in positioning protocols when there is no valid data:

a) All bits in the degree field are set to "1", together with the North/South flag bit, East/West flag bit set to "0".

b) All bits in the minute field are set to "0", together with the ∆ signal set to "1".

c) All bits in the second field are set to "1" (value "1111" = 60 s is out of range).

This pattern must be transmitted if the beacon transmits a message in self-test mode on the 406.0 MHz to 406.1 MHz band.

B.3.2. User Positioning Protocol

This protocol is only allowed in long messages with bit 25 = 1 and bit 26 = 1. The PDF-1 information field is similar to the user protocol defined in Section B.2.

The PDF-2 field is defined as follows:

- Bit 107: source of encoded position data, bit 107 = 0 means the encoded position data is provided by an external source, bit 107 = 1 means the encoded position data is provided by an internal source within the beacon.

- From bit 108 to bit 119: 12 bits of latitude information, including:

Bit 108: North/South flag bit (bit 108 = 0: north latitude, bit 108 = 1: south latitude).

Bit 109 to bit 115: representing degree value, from 0° to 90° with a resolution of 1°.

Bit 116 to bit 119: representing minute value, from 0' to 56' with a resolution of 4'.

(the default value of this field is 0 1111111 0000).

- From bit 120 to bit 132: 13 bits of longitude information, including:

Bit 120: East/West flag bit (bit 120 = 0: east longitude, bit 120 = 1: west longitude).

From bit 121 to bit 128: represents the degree value, from 0° to 180° with a resolution of 1°.

From bit 129 to bit 132: represents the minute value, from 0' to 56' with a resolution of 4'.

(The default value of this field is 0 11111111 0000).

B.3.3 Standard Positioning Protocol

Table B.5 Summary of the structure of the standard positioning protocol

- Bit 25 = 1, bit 26 = 0.

- Bit 27 to bit 36: 10-bit encoding for the country code.

- Bit 37 to bit 40: (= 0111) standard positioning protocol for PLB beacons.

- Bit 41 to bit 64: 24-bit identification data used to encode:

The type approval certificate number consisting of 10 bits (encoding values from 1 to 1023) in bits 41 to 50 and the serial number consisting of 14 bits (encoding values from 1 to 16383) in bits 51 to 64.

The type approval certificate number (C/S type approval certificate number) is the certification number for each type of beacon approved by the Cospas-Sarsat organization.

- Bit 65 to bit 74: 10 bits of information about latitude, including:

Bit 65: North/South flag bit (bit 65 = 0: North latitude, bit 65 = 1: South latitude).

Bit 66 to bit 74: represents the degree value, from 0° to 90° with a resolution of 15'.

(The default value of this field is 0 111111111).

- Bit 75 to bit 85: 11 bits of information about longitude, including:

Bit 75: East/West flag bit (bit 75 = 0: East longitude, bit 75 = 1: West longitude).

Bit 76 to bit 85: represents the degree value, from 0° to 180° with a resolution of 15'.

(The default value of this field is 0 1111111111).

- Bit 86 to bit 106: 21 bits of BCH-1 error correction code.

- Bit 107 to bit 110: default bits, with a value of 1101.

- Bit 111: bit 111 = 0 means that the position data encoded in the PDF-1 field is provided by an external positioning device, bit 111 = 1 means that the position data encoded in the PDF-1 field is provided by the integrated positioning device in the beacon.

- Bit 112: bit 112 = 0 means that the beacon does not have a 121.5 MHz auxiliary device, otherwise bit 112 = 1 means that the beacon has an integrated 121.5 MHz auxiliary device.

- Bit 113 to bit 122: Latitude position correction by a quantity Δ, specifically:

Bit 113 = 0 means the quantity Δ has a negative value, bit 113 = 1 means the quantity Δ has a positive value.

Bit 114 to bit 118 represent the minute value, from 0' to 30' with a resolution of 1'.

Bit 119 to bit 122 represent the second value, from 0" to 56" with a resolution of 4".

(The default value of this field is 1 00000 1111).

- Bit 123 to bit 132: Longitude position correction by a quantity Δ, specifically:

Bit 123 = 0 means the quantity Δ has a negative value, bit 123 = 1 means the quantity Δ has a positive value.

Bit 124 to bit 128 represent the minute value, from 0' to 30' with a resolution of 1'.

Bit 129 to bit 132 represent the second value, from 0" to 56" with a resolution of 4".

(The default value of this field is 1 00000 1111).

- Bit 133 to bit 144: 12 bits of BCH-2 error correction code.

B.3.4 National Positioning Protocol

Table B.6 Summary of the structure of the national positioning protocol

- Bit 25 = 1, bit 26 = 0.

- From bit 27 to bit 36: Country code.

- From bit 37 to bit 40: (= 1011) national positioning protocol for PLB beacons.

- From bit 41 to bit 58: Contains 18 bits of encoded identification data for the serial number provided by the authority.

- From bit 59 to bit 71: 13 bits of information about latitude, including:

Bit 59: North/South flag bit (bit 59 = 0 - North latitude, bit 59 = 1 - South latitude).

From bit 60 to bit 66: represents the degree value, from 0° to 90° with a resolution of 1°.

From bit 67 to bit 71: represents the minute value, from 0' to 58' with a resolution of 2'.

(The default value of this field is 0 1111111 00000).

- From bit 72 to bit 85: 14 bits of information about longitude, including:

Bit 72: East/West flag bit (bit 72 = 0 - East longitude, bit 72 = 1 - West longitude).

From bit 73 to bit 80: represents the degree value, from 0° to 180° with a resolution of 1°.

From bit 81 to bit 85: represents the minute value, from 0' to 58' with a resolution of 2'.

(The default value of this field is 0 11111111 00000).

- From bit 86 to bit 106: 21 bits of BCH-1 error correction code.

- From bit 107 to bit 109: default bits with a value of 110.

- Bit 110: additional data flag bit, bit 110 = 1 means that the Δ position data is encoded in the PDF-2 field, bit 110 = 0 means that the data in the PDF-2 field is defined according to the country.

- Bit 111: bit 111 = 0 means that the position data encoded in the PDF-1 field is provided by an external positioning device, bit 111 = 1 means that the position data encoded in the PDF-1 field is provided by the integrated positioning device in the beacon.

- Bit 112: bit 112 = 0 means that the beacon does not have a 121.5 MHz auxiliary device, otherwise bit 112 = 1 means that the beacon has an integrated 121.5 MHz auxiliary device.

- From bit 113 to bit 119: If bit 110 = 1, latitude position correction by a quantity Δ, specifically:

Bit 113 = 0 means the quantity Δ has a negative value, bit 113 = 1 means the quantity Δ has a positive value.

From bit 114 to bit 115 represent the minute value, from 0' to 3' with a resolution of 1'.

From bit 116 to bit 119 represent the second value, from 0" to 56" with a resolution of 4".

(The default value of this field is 1 00 1111).

If bit 110 = 0 then from bit 113 to bit 119 are reserved for the country's use.

- From bit 120 to bit 126: If bit 110 = 1, longitude position correction by a quantity Δ, specifically:

Bit 120 = 0 means the quantity Δ has a negative value, bit 120 = 1 means the quantity Δ has a positive value.

Bit 121 to bit 122 represent the minute value, from 0' to 3' with a resolution of 1'.

Bit 123 to bit 126 represent the second value, from 0" to 56" with a resolution of 4".

(The default value of this field is 1001111).

If bit 110 = 0 then from bit 120 to bit 126 are reserved for the country's use.

- From bit 127 to bit 132: Additional information about beacon identification (reserved for the country's use). The default value of this field is 000000.

- From bit 133 to bit 144: 12 bits of BCH-2 error correction code.

B.3.5 Service Line Response Positioning Protocol

Table B.7 Summary of the structure of the service line response positioning protocol

- Bit 25 = 1, bit 26 = 0.

- Bit 27 to bit 36: Country code.

- Bit 37 to bit 40: (= 1101) for the service line response positioning protocol.

- Bit 41 to bit 42: Used to identify beacon types; (= 10) for PLB beacons.

- Bit 43 to bit 58: 16 bits of encoded identification data for the serial number provided by the authority.

- Bit 59 to bit 71: 13 bits of information about latitude, including:

Bit 59: North/South flag bit (bit 59 = 0 - North latitude, bit 59 = 1 - South latitude).

Bit 60 to bit 66: represents the degree value, from 0° to 90° with a resolution of 1°.

Bit 67 to bit 71: represents the minute value, from 0' to 58' with a resolution of 2'.

(The default value of this field is 0 1111111 00000).

- Bit 72 to bit 85: 14 bits of information about longitude, including:

Bit 72: East/West flag bit (bit 72 = 0 - East longitude, bit 72 = 1 - West longitude).

Bit 73 to bit 80: represents the degree value, from 0° to 180° with a resolution of 1°.

Bit 81 to bit 85: represents the minute value, from 0' to 58' with a resolution of 2'.

(The default value of this field is 0 11111111 00000).

- Bit 86 to bit 106: 21 bits of BCH-1 error correction code.

- Bits 107 to 109: default bits with value = 110.

- Bit 110: additional data flag bit, bit 110 = 1 means that the Δ position data is encoded in the PDF-2 field, bit 110 = 0 means that the data in the PDF-2 field is defined according to the country.

- Bit 111: bit 111 = 0 means that the position data encoded in the PDF-1 field is provided by an external positioning device, bit 111 = 1 means that the position data encoded in the PDF-1 field is provided by the integrated positioning device in the beacon.

- Bit 112: bit 112 = 0 means that the beacon does not have a 121.5 MHz auxiliary device, otherwise bit 112 = 1 means that the beacon has an integrated 121.5 MHz auxiliary device.

- Bits 113 to 119: If bit 110 = 1, adjust position by a latitude ∆ amount, specifically:

Bit 113 = 0 means the quantity Δ has a negative value, bit 113 = 1 means the quantity Δ has a positive value.

Bit 114: Set = 0 if no position adjustment is needed.

Bit 115: Indicates the minute value (0 or 1).

Bits 116 to 119 indicate the second value, from 0" to 56" with a resolution of 4".

(Default value for this field = 1001111)

If bit 110 = 0 then from bit 113 to bit 119 are reserved for the country's use.

- Bits 120 to 126: If bit 110 = 1, adjust position by a longitude ∆ amount, specifically: Bit 120 = 0 indicates a negative ∆ value, bit 120 = 1 indicates a positive ∆ value.

Bit 121: Set = 0 if no position adjustment is needed.

Bit 122: Indicates the minute value (0 or 1).

Bit 123 to bit 126 represent the second value, from 0" to 56" with a resolution of 4".

(Default value for this field = 1001111)

If bit 110 = 0 then from bit 120 to bit 126 are reserved for the country's use.

- Bits 127 to 132: RLS Data

100000 RLM - only requests type 1

010000 RLM - only requests type 2

110000 RLM - requests both types 1 and 2 (default)

- Bit 133 to bit 144: 12 bits of BCH-2 error correction code.

Section B.3.6. Test positioning protocols

The test protocol used for all encoding methods encoded at bits 37 to 39 (protocol code) is "111". Bit 40 is used to distinguish between standard test positioning protocols (bit 40 = "0") and national test positioning protocols (bit 40 = "1").

 

ANNEX C (For reference)

Test setup diagram

Figure C.1. Sample test location

Figure C.2. Test setup

Figure C.3. Antenna perpendicular to the signal propagation direction

Figure C.4. Antenna not perpendicular to the signal propagation direction

 

QCVN 110:2017/BTTTT was compiled by the Post and Telecommunications Science and Technology Institute, reviewed by the Department of Science and Technology, and promulgated along with Circular No. 24/2017/TT-BTTTT dated October 17, 2017.

[1] C/S G.005: "COSPAS-SARSAT guidelines on 406 MHz Beacon coding, registration and type approval".

[2] ETSI EN 302 152-1 V1.1.1 (2003-11) European Standard (Telecommunications series) Electromagnetic compatibility and Radio spectrum Matters (ERM); Satellite Personal Locator Beacons (PLBs) operating in the 406,0 MHz to 406,1 MHz frequency band; Part 1: Technical characteristics and methods of measurement.

[3] ETSI EN 300 066 V1.3.1: Electromagnetic Compatibility and Radio Spectrum Matters (ERM); Float-free maritime satellite Emergency Position Indicating Radio Beacons (EPIRBs) operating in the 406,0 MHz to 406,1 MHz frequency band; Technical characteristics and methods of measurement.