GNSS for operating vehicles — Technical specification for vehicle terminals
(JT/T 794-2019)
Professional Standard Amendment 1
Add the item a) “Signal receiving: It can at least receive B1I or B1C signals of BeiDou navigation satellite system;” in the subclause 6.2 "Satellite positioning module". The original items a) ~ e) are adjusted to b) ~ f) respectively. After the amendment, the contents of 6.2 "Satellite positioning module" are as follows:
The satellite positioning module shall meet the following technical requirements:
a) Signal receiving: It can at least receive B1I or B1C signals of BeiDou navigation satellite system;
b) Number of satellite signal receiving channels: Not less than 12;
c) Sensitivity: Higher than -130 dBm;
d) Positioning accuracy: The horizontal positioning accuracy is not more than 15 m, the elevation positioning accuracy is not more than 30 m, and the velocity positioning accuracy is not more than 2 m/s; Differential positioning accuracy (optional) is not more than 1 m;
e) Minimum location update rate: 1 Hz;
f) Hot start: The capture duration shall not exceed 10 s.
Foreword
Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
This standard is developed in accordance with the rules given in GB/T 1.1-2009.
This standard replaces JT/T 794-2011 GNSS for operating vehicles — Technical specification for vehicle terminals. In addition to editorial changes, the following main technical changes have been made with respect to JT/T 794-2011:
——The definitions of start time of travelling, effective parking and cumulative driving time have been added (see 3.1.3, 3.1.4 and 3.1.6);
——The definition of single continuous driving time has been modified (see 3.1.5 herein and 3.1.3 in 2011 edition);
——The terminal IMEI number has been added (see 4.3);
——The protection requirements for trailer terminal have been added, (see 4.6);
——The requirements for self-test frequency have been added (see 5.1);
——The function of BeiDou positioning has been added (see 5.2.1);
——TD-LTE, FDD-LTE and LTE-V2X communication modes have been added (see 5.3.1);
——The requirements for encrypted transmission have been added (see 5.3.2);
——The requirements for driver's identity have been modified (see 5.4.1 herein and 5.4.1 in 2011 edition);
——The requirements for taxi operation data acquisition have been deleted (5.4.5 in 2011 edition);
——The requirements for travelling data record have been modified (see 5.5 herein and 5.5 in 2011 edition);
——The information acquisition requirements for electronic travel permit have been modified and the requirements for data transmission encryption have been added (see 5.4.2 herein and 5.4.2 in 2011 edition);
——The requirements for image information have been modified and the requirements for highest resolution have been added (see 5.4.6 herein and 5.4.7 in 2011 edition);
——The requirements for audio information have been deleted (5.4.8 in 2011 edition);
——The requirements for video information have been modified and the requirements for highest resolution and video frame rate have been added (see 5.4.7 herein and 5.4.9 in 2011 edition);
——The requirements for vehicle state information acquisition have been added (see 5.4.8);
——The monitoring requirements have been modified, and the requirements for monitoring through data link and storing the monitoring data locally have been added (see 5.6 herein and 5.6 in 2011 edition);
——The call requirements have been modified, and the call function through data link have been added (see 5.7 herein and 5.7 in 2011 edition);
——The time requirement for entering sleep state after the engine shutdown and the sleep requirement of trailer terminals have been added, and the requirements for vehicle start-up and ignition detection function and the average power requirement of terminals in sleep have been modified (see 5.8);
——The reminders about restricted period, antenna disconnection, tyre pressure abnormality, collision, rollover, unsafe driving behavior and right-turning blind zone abnormality have been added (see 5.9);
——The terminal management requirements have been modified, and the requirements for data transmission encryption have been added (see 5.10 herein and 5.10 in 2011 edition);
——The requirements for calling service have been deleted (5.13 in 2011 edition);
——The requirements for multi-centre access have been modified, as well as requirements for domain name access mode (see 5.13 herein and 5.14 in 2011 edition);
——The requirements for automatic shutdown of communication and ETC function have been added (see 5.14 and 5.15);
——The requirements for power-off protection performance have been deleted (see 6.6.2 in 2011 edition);
——The adaptability to mechanical environment has been modified (see 6.5.2 herein and 6.5.2 in 2011 edition);
——The transient immunity requirements have been deleted (6.6.2 in 2011 edition);
——The requirements for transient conducted immunity along the power line have been added (see 6.6.2);
——The requirements for immunity to disturbances from electrical transient transmission by coupling have been added (see 6.6.3);
——The requirements for vehicle ignition resistance have been deleted (6.7 in 2011 edition);
——The installation requirements of the terminal host have been modified, and it has been made clear that the vehicle speed signal input of the terminal shall be taken from the pulse signal of the vehicle speed sensor, and the brake signal input from the brake switch quantity signal (see 7.2);
——The inspection rules have been added (see Clause 8);
——Table A.1 "Basic functional requirements of various transport vehicle terminals" in Annex A has been modified (see Annex A hereto and Annex A to 2011 edition).
This standard was proposed by and is under the jurisdiction of National Technical Committee on Road Transport of Standardization Administration of China (SAC/TC 521).
The previous edition of this standard is as follows:
——JT/T 794-2011.
GNSS for operating vehicles —
Technical specification for vehicle terminals
1 Scope
This standard specifies the general requirements, functions, performance and installation requirements and inspection rules for the vehicle terminals of GNSS for operating vehicles.
This standard is applicable to the vehicle terminals on-board in GNSS for operating vehicles.
2 Normative references
The following referenced documents are indispensable for the application of this standard. For dated reference, only the edition cited applies. For undated references, the latest edition (including any amendment) applies.
GB/T 4208 Degrees of protection provided by enclosure (IP code)
GB/T 19056 Vehicle travelling data recorder
GB/T 19951-2005 Road vehicles — Test methods for electrical disturbances from electrostatic discharge
GB/T 21437.2-2008 Road vehicles — Electrical disturbances from conduction and coupling — Part 2: Electrical transient conduction along supply lines only
GB/T 21437.3-2012 Road vehicles — Electrical disturbances from conduction and coupling — Part 3: Electrical transient transmission by capacitive and inductive coupling via lines other than supply lines
GB/T 28046.1 Road vehicles — Environmental conditions and testing for electrical and electronic equipment — Part 1: General
GB/T 28046.3-2011 Road vehicles — Environmental conditions and testing for electrical and electronic equipment — Part 3: Mechanical loads
JT/T 617.5 Regulations concerning road transportation of dangerous goods — Part 5: Consignment
JT/T 766-2009 Technical requirements for shipborne monitoring equipment of BeiDou navigation satellite system
JT/T 825 IC card license for road transportation
QC/T 1067.1 Connector used in automobile wire harness and electrical device — Part 1: Definition, test method and requirement
GB/T 31465.3 Road vehicles — Fuse-link — Part 3: Fuse-link with blade type
QC/T 414 Design rule of color and type code for automotive cables
YD/T 1050 Test Specification for 800 MHz CDMA Digital Celluar Mobile Telecommunication Network: Terminal Part
YD/T 1214 Technical requirement of 900/1800MHz TDMA Digital Cellular Mobile Telecommunication Network General Packet Radio Service (GPRS) Equipment: Mobile Stations
YD/T 1367 Technical requirements for user equipment of 2GHzTD-SCDMA digital cellular mobile communication network
YD/T 1547 Technical requirements for 2GHz WCDMA digital cellular mobile communication network user equipment (Phase 3)
YD/T 1558 Technical Requirements of mobile station for 800MHz/2GHz cdma2000 digital cellular mobile telecommunication network
YD/T 2575 Technical requirements for user equipment of TD-LTE digital cellular mobile telecommunications network (Phase 1)
YD/T 2577 Technical requirements for user equipment of LTE-FDD digital cellular mobile telecommunications network (Phase 1)
3 Terms, definitions and abbreviations
3.1 Terms and definitions
For the purpose of this document, the following terms and definitions apply.
3.1.1
firmware
embedded software running in the terminal microprocessor
3.1.2
electronic travel permit
electronic data including vehicle, passenger and cargo information
3.1.3
start time of travelling
time that the state of vehicle changes from stationary to travelling (at a speed of more than 0 km/h for more than 10 s)
3.1.4
effective parking
action during which the state of vehicle changes from stationary to travelling (at a speed of 0 km/h) for at least 20 min
3.1.5
single continuous driving time
duration from the start time of the travelling till the start time of effective parking for the same driver
3.1.6
cumulative driving time
sum of single continuous driving time of the same driver within 24 h
3.1.7
monitoring centre
software platform for monitoring vehicle road transport
3.1.8
sleep
special state that the terminal remains in contact with the monitoring centre after the vehicle stalls
3.2 Abbreviations
For the purposes of this document, the following abbreviations apply.
CAN——Controller Area Network
IMEI——International Mobile Equipment Identity
GSM——Global System for Mobile Communication
CDMA——Code Division Multiple Access
TD-SCDMA——Time Division-Synchronous Code Division Multiple Access
WCDMA——Wideband Code Division Multiple Access
CDMA2000——Code Division Multiple Access 2000
TD-LTE——Time Division-Long Term Evolution
FDD-LTE——Frequency Division Duplexing-Long Term Evolution
LTE-V2X——Long Term Evolution-Vehicle to Everything
JPEG——Joint Photographic Experts Group
ETC——Electronic Toll Collection
4 General requirements
4.1 Composition of vehicle terminal
4.1.1 Host
The host of vehicle terminal [hereinafter referred to as the "terminal"] shall include microprocessor, data memory (capacity: not less than 8 GB), satellite positioning module, vehicle state information acquisition module, wireless communication module, real-time clock, data acquisition interface, which may include display, printer and card reader. If the terminal has display, printer, card reader which are not included in the host, they can be listed as accessory devices, but the host shall maintain corresponding interfaces.
4.1.2 Accessory device
External devices shall include satellite positioning antenna, wireless communication antenna, emergency alarm button and voice broadcasting device. According to the basic functional requirements of different categories of vehicles in Annex A, such devices include communication devices, operation keys, card readers, printers, displays, vehicle operation status information display, information release and other devices, as well as information acquisition devices for images, videos, audio, driver's identity, electronic travel permit, logistics, operation, toll settlement and service evaluation, etc.
4.2 Appearance
The appearance of terminals shall be free of rust, rust spots, cracks, fading, stains, deformation, peeling of plating and coating, obvious scratches or burrs; the plastic parts shall be free of blistering, cracking or deformation; the structural parts and control components shall be complete and free from mechanical damage.
4.3 Nameplate
Terminals shall have a nameplate with clear and durable markings. The nameplate shall be mounted in an obvious position on the outer surface of the host, and the size of the nameplate shall be suitable for the structural size of the host.
The nameplate shall bear the following information:
a) product name, specification and model;
b) name and trademark of terminal manufacturer;
c) end of-manufacturing date and number;
d) implementation standard reference to terminals;
e) terminal IMEI No.
4.4 Characters, graphics and markings
The terminals shall be provided with instructions for use. The buttons, interfaces and other parts of the panel shall be provided with characters, graphics and other markings, and meet the following requirements:
a) Durable and eye-catching;
b) The characters in the instructions for use, nameplates and markings shall be in Chinese, which may be accompanied with other languages as necessary. In that case, make sure Chinese characters are on the top or left side of other languages.
4.5 Material
The material shall meet the requirements of non-toxicity and non-radioactivity.
4.6 Casing protection
When the host does not contain display, printer or card reader, the casing shall be protected as required by IP53 in GB/T 4208; when the host includes display, printer, card reader and other devices or one of them, the casing shall be protected as required by IP43 in GB/T 4208; the casing of trailer terminals shall be protected as required by IP67 in GB/T 4208.
5 Functional requirements
5.1 Self-test
The terminals shall have self-test function, and shall be able to clearly indicate its current main state through signal lamp or display screen, including the working state of satellite positioning and communication modules, the state of main power supply, the state of satellite positioning antenna, and the state of other devices connected with the terminal host. The terminal shall be able to perform self-test at the preset frequency, which should be set by the monitoring centre. In case of failure, information such as failure types shall be indicated by signal lamp or display screen, stored and uploaded to the monitoring centre.
5.2 Positioning
5.2.1 Positioning function
The positioning function of terminals includes the followings:
a) The terminals shall be able to provide real-time positioning status information such as time, longitude, latitude, speed, elevation and direction, which can be stored inside the terminals and uploaded to the monitoring centre through wireless communication, with the differential positioning function optional;
b) The terminals that support multiple satellite positioning modes shall be able to upload the current positioning mode and support positioning based on the satellite positioning mode designated by the monitoring centre;
c) The terminal shall be able to store not less than 10,000 pieces of positioning data in a first-in-first-out (FIFO) mode when communication is interrupted (in blind zone), and upload the stored positioning data after communication is resumed, if needed, in a compressed mode;
d) The terminals shall support uploading positioning data at an interval of time or distance, or in external event triggering mode. When the terminal is in sleep state, the terminal shall also upload positioning data at a certain interval of time or distance that may be set by the monitoring centre;
e) The terminals using BeiDou satellite positioning shall have BeiDou satellite information collection function, and shall store and report BeiDou positioning results and detailed positioning data of satellite positioning module to the monitoring centre, which should at least include signal-to-noise ratio and effective number of satellites;
f) The terminals using BeiDou satellite positioning shall be able to respond to two instructions issued by the monitoring centre, i.e. adding BeiDou information acquisition area and deleting BeiDou information acquisition area;
g) The terminals using BeiDou satellite positioning shall be able to store at least 24 rectangular areas for satellite information acquisition issued by monitoring centre. When the vehicle enters a certain rectangular area, the function of satellite signal acquisition is automatically started and uploaded at a specified frequency, and the acquisition and uploading are automatically stopped when it leaves the area;
h) The terminals using BeiDou satellite positioning shall be able to store or upload detailed positioning data such as current positioning mode and satellite signal coverage status information to the monitoring centre based on the parameter settings specified by the monitoring centre. The terminals can store at least 2,000 pieces of detailed positioning data. If the stored data exceeds the maximum capacity, the first stored data shall be discarded in temporal sequence;
i) Online upgrade and local upgrade functions of BeiDou and other GNSS satellite dual-mode positioning modules shall be supported.
5.2.2 Technical requirements for positioning
The positioning function of terminals shall meet the following technical requirements:
a) Submission at regular time interval: In the travelling state, the minimum time interval of submission is not more than 5 s, and the maximum time interval is not more than 30 s;
b) Submission at regular distance interval: In the travelling state, the minimum distance interval of submission is not more than 100 m, and the maximum distance interval is not more than 500 m;
c) Submission at regular time and distance interval: In the travelling state, the terminal can submit positioning data at the time and distance interval set by the monitoring centre;
d) Real-time positioning: The period is not more than 10 s from the terminal receiving the real-time positioning request from the monitoring centre till the terminal responding;
e) Accuracy of recording time: The permissible error of cumulative time within 24 h is within ±5 s.
5.3 Communication
5.3.1 Communication mode
The terminals shall support general CSM or CDMA mode, and can support communication modes based on TD-SCDMA, WCDMA, CDMA2000, TD-LTE, FDD-LTE, LTE-V2X and other wireless communication networks and the transmission mechanism of BeiDou Navigation Satellite System (BDS) as required. When the wireless network where the vehicle is located supports packet data transmission, the terminal shall give priority to the packet data transmission mode; otherwise, it may switch to short message mode to transmit data. When the wireless communication network cannot be connected, BeiDou communication mode may be used as needed.
5.3.2 Communication requirements
The communication requirements for terminals shall include the followings:
a) The terminals shall support at least two remote connections, namely, the connection between the main monitoring centre and the backup monitoring centre, and shall automatically switch to the backup monitoring centre when the communication with the main monitoring centre is interrupted;
b) If the terminals are unable to access the local wireless network, the data shall be stored in a FIFO mode and transmitted together until registering to the wireless network;
c) The terminals shall support the functions of receiving and sending data in batches and continuous transmission of breakpoints;
d) Encryption measures should be taken for communication between terminal and monitoring centre.
5.4 Information acquisition
5.4.1 Driver’s identity
The driver identification device of the terminal shall meet the requirements of JT/T 825, and support acquiring the qualification certificate information through remote authentication after encryption and uploading it to the monitoring centre.
The terminals shall be able to automatically detect the action of replacing the driver's IC card qualification certificate, and realize the corresponding driver identification function.
5.4.2 Electronic travel permit
The electronic travel permit for dangerous goods transport shall meet the requirements of JT/T 617.5, and the terminals shall be able to receive the electronic travel permit information sent to the terminals by the dangerous goods transport enterprise through encryption or digital identity authentication.
5.4.3 Vehicle CAN bus data
A terminal shall have two built-in CAN bus communication interfaces, and acquire information on vehicle running state through CAN bus.
5.4.4 Vehicle loading state
The terminals can be provided with the interface of vehicle loading state detection device; alternatively, the vehicle loading state can be determined by manual input and uploaded to the monitoring centre.
5.4.5 Toll settlement data
The terminal can be provided with an interface of toll settlement data acquisition device, which supports acquiring toll settlement information and uploading it to the monitoring centre.
5.4.6 Image information
The terminals can be provided with the functions of image information acquisition and storage; support the functions of image information acquisition, storage, uploading, retrieval & uploading through the control of monitoring centre, timing and event triggering; and support the export of image information through USB interface. Image information acquisition shall meet the following requirements:
a) It supports at least two cameras;
b) The cameras support infrared light supplement;
c) It sets at least two imaging resolutions, with the highest resolution of not less than 720P and the lowest of not less than D1;
d) The minimum acquisition interval is 5 s;
e) The current date and time can be displayed in the image (24-hour time system) in the format of yyyy-mm-dd hh: mm: ss;
f) It supports the storage of images in JPEG format at least;
g) It stores at least 2,000 images in a FIFO mode;
h) It supports marking the image data, which shall not be overwritten.
5.4.7 Video information
The terminals can be provided with the functions of video information acquisition and storage; support the functions of image information acquisition, compression, storage, uploading, retrieval & uploading through the control of monitoring centre and event triggering; support the real-time uploading of video data; and support the export of video data through local data interface. Video information acquisition shall meet the following requirements:
a) Support at least two cameras;
b) It can set at least two imaging resolutions, with the highest resolution of not less than 720P;
c) The frame rate of locally stored video is not less than 25 FPS, and the frame rate of uploaded video is not less than 15 FPS;
d) The current date and time can be displayed in the video (24-hour time system) in the format of yyyy-mm-dd hh: mm: ss;
e) The video acquisition coding format is H.264 or H.265;
f) It can store at least 48 h of video data;
g) It supports marking the video data, which shall not be overwritten.
5.4.8 Vehicle state information
The terminal shall support acquiring information such as switch quantity and analog quantity of the vehicle, including braking, left steering, right steering, passing beam and driving beam. At least 5 switch quantities and 2 analog quantities shall be acquired, and the acquired information shall be uploaded to the monitoring centre together with the positioning data.
5.5 Travelling data record
The terminals shall have the function of automobile travelling data record, and provide data analysis software, which supports the functions of real-time uploading of travelling data record, conditional retrieval uploading and data interface export. The data analysis software, function of terminal travelling data record and storage performance shall meet the requirements of GB/T 19056.
5.6 Monitoring
The terminals may have the function of monitoring through the circuit domain or data link, and the speaker shall be turned off when monitoring. When monitoring through the circuit domain, the following requirements shall be met:
a) After the monitoring centre sends the monitoring instruction, the terminals automatically dial the monitoring number carried by the monitoring instruction to enter the monitoring state;
b) Save data to be uploaded during monitoring and upload it after monitoring;
c) In the case of manual alarm, terminals without image, audio and video acquisition functions automatically dial a preset monitoring number to enter the monitoring state;
d) When the terminals dial the monitoring number, dial another three times at an interval of 30 s, in the case of not getting through for the first time.
5.7 Calls
The terminals can provide calls through circuit domain or data link, including call restriction, voice storage, telephone directory management, telephone callback, volume adjustment, and automatic off-hook of incoming calls. The function of terminal call shall meet the following requirements:
a) The data to be uploaded shall be saved for a call through circuit domain, and uploaded after the call is ended;
b) The terminal telephone directory shall be provided with a storage capacity of not less than 20 contacts;
c) The terminal may be set by the monitoring centre to allow only incoming calls and only outgoing calls.
5.8 Sleep
The terminal shall be provided with the function of vehicle start-up detection (except trailer terminals). One hour after the vehicle stalled, the terminal sends a terminal sleep signal to the monitoring centre, enters the sleep state, and ends the sleep state after the next start-up. The terminal in sleeping shall meet the following requirements:
a) Turn off other unnecessary devices except the wireless communication module, and automatically wake the satellite positioning module when uploading is required;
b) The data upload frequency may be remotely set by the monitoring centre or automatically and continuously reduced according to the parameters set during initialization;
c) After the battery undervoltage alarm, the terminal turns to the built-in standby battery for power supply, and automatically powers off when the built-in standby battery is run out;
d) The average power of the terminal during the sleep period does not exceed 1.5 W.
5.9 Warning
5.9.1 General requirements
When the terminal triggers the warning, it shall immediately upload the warning information to the monitoring centre or send the short message about warning information to the designated mobile phone as needed, and can receive the instruction from the monitoring centre to cancel the warning. The warning mobile phone number may be set remotely by the monitoring centre. When the monitoring centre sends instructions to the terminal based on the vehicle position, state information or safety supervision needs uploaded by the vehicle, the terminal shall prompt the driver about the warning information by voice broadcasting, which may be combined with sound, light and text. Terminal warning function includes two parts, manual alarm and automatic reminder.
5.9.2 Manual alarm
Manual alarm is triggered by the driver according to the actual situation on site. When encountering emergency including robbery, traffic accident and vehicle breakdown, the driver uploads alarm information to the monitoring centre by touching the emergency alarm button, while turning off the voice broadcasting module. If the terminal is provided with the image and video acquisition function, it shall be enabled immediately. Where there is no mobile communication signal, the terminal with BDS communication function may upload alarm information by sending send short message through the system. Manual alarm shall be provided with the function of preventing misoperation.
5.9.3 Automatic reminder
Automatic reminder means that the driver does not operate the terminal, and it is triggered according to the conditions set by the monitoring centre, including the following functions:
a) Area reminder: There shall not be less than 24 polygonal or circular areas stored in the terminal. And the reminder will be triggered when the vehicle enters or exits the forbidden areas, and the monitoring area may be set remotely by the monitoring centre.
b) Reminder about restricted period: It may be triggered in the terminal according to the preset restricted period or by receiving the information sent by the monitoring centre to warn the driver that he or she is currently driving in the restricted period. The default restricted period is 2:00 am to 5:00 am.
c) Route deviation reminder: There shall not be less than 24 routes stored in the terminal, and each route shall be a broken line covering 16 or more points. It will be triggered when the vehicle deviates from the set route, and the route to be monitored may be set remotely by the monitoring centre.
d) Overspeed reminder: The terminal shall trigger the reminder according to the preset speed threshold or by receiving the information from the monitoring centre.
e) Drowsy driving reminder: It is triggered when the single continuous driving time and cumulative driving time exceed the drowsy driving time threshold, which may be set remotely by the monitoring centre. The default single continuous driving time is 4 h, and the default cumulative driving time is 8 h.
f) Battery under-voltage reminder: It is triggered when the terminal detects that the battery voltage of the vehicle is lower than the preset value. At the same time, the terminal must stop tapping into the power supply from the vehicle battery but turn to the built-in standby battery for power supply.
g) Power-off reminder: It is triggered when the main power supply for the terminal is turned off.
h) Antenna disconnection reminder: It is triggered when the terminal satellite positioning antenna is cut.
i) Overtime parking reminder: It is triggered when the parking time exceeds the preset duration in the system.
j) Terminal fault reminder: It is triggered when the terminal host and the external devices connected with the terminal host work abnormally, and uploaded to the monitoring centre.
k) Tyre pressure abnormality reminder: Communication between the terminal and the vehicle tyre pressure monitoring system is available, and the terminal can receive and upload information about the tyre pressure abnormality reminder.
l) Rollover reminder: It is triggered when the vehicle is rolled over.
m) Collision reminder: It is triggered when there is a collision accident.
n) Unsafe driving behavior reminder: Communication between the terminal and the system of monitoring on driver's unsafe driving behavior is available, and the terminal receives and uploads the reminder information about the driver's unsafe driving behavior, e.g., smoking, speaking on the phone, distraction and dozing off.
o) Right-turning blind zone abnormality reminder: Communication between the terminal and the right-turning blind zone monitoring system is available. When the vehicle turns right, whereas there are pedestrians, non-motor vehicles or other motor vehicles in the right-turning blind zone, the terminal receives and uploads the information.
Foreword i
1 Scope
2 Normative references
3 Terms, definitions and abbreviations
4 General requirements
5 Functional requirements
6 Performance requirements
7 Installation requirements
8 Inspection rules
Annex A (Normative) Basic functional requirements of various transport vehicle terminals
JT/T 794-2019/XG1-2021, JT 794-2019/XG1-2021, JT 794-2019XG1-2021, JT/T794-2019/XG1-2021, JT/T 794, JT/T794, JT794-2019/XG1-2021, JT 794, JT794, JT794-2019XG1-2021, JT 794, JT794
Introduction of JT/T 794-2019/XG1-2021
GNSS for operating vehicles — Technical specification for vehicle terminals
(JT/T 794-2019)
Professional Standard Amendment 1
Add the item a) “Signal receiving: It can at least receive B1I or B1C signals of BeiDou navigation satellite system;” in the subclause 6.2 "Satellite positioning module". The original items a) ~ e) are adjusted to b) ~ f) respectively. After the amendment, the contents of 6.2 "Satellite positioning module" are as follows:
The satellite positioning module shall meet the following technical requirements:
a) Signal receiving: It can at least receive B1I or B1C signals of BeiDou navigation satellite system;
b) Number of satellite signal receiving channels: Not less than 12;
c) Sensitivity: Higher than -130 dBm;
d) Positioning accuracy: The horizontal positioning accuracy is not more than 15 m, the elevation positioning accuracy is not more than 30 m, and the velocity positioning accuracy is not more than 2 m/s; Differential positioning accuracy (optional) is not more than 1 m;
e) Minimum location update rate: 1 Hz;
f) Hot start: The capture duration shall not exceed 10 s.
Foreword
Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
This standard is developed in accordance with the rules given in GB/T 1.1-2009.
This standard replaces JT/T 794-2011 GNSS for operating vehicles — Technical specification for vehicle terminals. In addition to editorial changes, the following main technical changes have been made with respect to JT/T 794-2011:
——The definitions of start time of travelling, effective parking and cumulative driving time have been added (see 3.1.3, 3.1.4 and 3.1.6);
——The definition of single continuous driving time has been modified (see 3.1.5 herein and 3.1.3 in 2011 edition);
——The terminal IMEI number has been added (see 4.3);
——The protection requirements for trailer terminal have been added, (see 4.6);
——The requirements for self-test frequency have been added (see 5.1);
——The function of BeiDou positioning has been added (see 5.2.1);
——TD-LTE, FDD-LTE and LTE-V2X communication modes have been added (see 5.3.1);
——The requirements for encrypted transmission have been added (see 5.3.2);
——The requirements for driver's identity have been modified (see 5.4.1 herein and 5.4.1 in 2011 edition);
——The requirements for taxi operation data acquisition have been deleted (5.4.5 in 2011 edition);
——The requirements for travelling data record have been modified (see 5.5 herein and 5.5 in 2011 edition);
——The information acquisition requirements for electronic travel permit have been modified and the requirements for data transmission encryption have been added (see 5.4.2 herein and 5.4.2 in 2011 edition);
——The requirements for image information have been modified and the requirements for highest resolution have been added (see 5.4.6 herein and 5.4.7 in 2011 edition);
——The requirements for audio information have been deleted (5.4.8 in 2011 edition);
——The requirements for video information have been modified and the requirements for highest resolution and video frame rate have been added (see 5.4.7 herein and 5.4.9 in 2011 edition);
——The requirements for vehicle state information acquisition have been added (see 5.4.8);
——The monitoring requirements have been modified, and the requirements for monitoring through data link and storing the monitoring data locally have been added (see 5.6 herein and 5.6 in 2011 edition);
——The call requirements have been modified, and the call function through data link have been added (see 5.7 herein and 5.7 in 2011 edition);
——The time requirement for entering sleep state after the engine shutdown and the sleep requirement of trailer terminals have been added, and the requirements for vehicle start-up and ignition detection function and the average power requirement of terminals in sleep have been modified (see 5.8);
——The reminders about restricted period, antenna disconnection, tyre pressure abnormality, collision, rollover, unsafe driving behavior and right-turning blind zone abnormality have been added (see 5.9);
——The terminal management requirements have been modified, and the requirements for data transmission encryption have been added (see 5.10 herein and 5.10 in 2011 edition);
——The requirements for calling service have been deleted (5.13 in 2011 edition);
——The requirements for multi-centre access have been modified, as well as requirements for domain name access mode (see 5.13 herein and 5.14 in 2011 edition);
——The requirements for automatic shutdown of communication and ETC function have been added (see 5.14 and 5.15);
——The requirements for power-off protection performance have been deleted (see 6.6.2 in 2011 edition);
——The adaptability to mechanical environment has been modified (see 6.5.2 herein and 6.5.2 in 2011 edition);
——The transient immunity requirements have been deleted (6.6.2 in 2011 edition);
——The requirements for transient conducted immunity along the power line have been added (see 6.6.2);
——The requirements for immunity to disturbances from electrical transient transmission by coupling have been added (see 6.6.3);
——The requirements for vehicle ignition resistance have been deleted (6.7 in 2011 edition);
——The installation requirements of the terminal host have been modified, and it has been made clear that the vehicle speed signal input of the terminal shall be taken from the pulse signal of the vehicle speed sensor, and the brake signal input from the brake switch quantity signal (see 7.2);
——The inspection rules have been added (see Clause 8);
——Table A.1 "Basic functional requirements of various transport vehicle terminals" in Annex A has been modified (see Annex A hereto and Annex A to 2011 edition).
This standard was proposed by and is under the jurisdiction of National Technical Committee on Road Transport of Standardization Administration of China (SAC/TC 521).
The previous edition of this standard is as follows:
——JT/T 794-2011.
GNSS for operating vehicles —
Technical specification for vehicle terminals
1 Scope
This standard specifies the general requirements, functions, performance and installation requirements and inspection rules for the vehicle terminals of GNSS for operating vehicles.
This standard is applicable to the vehicle terminals on-board in GNSS for operating vehicles.
2 Normative references
The following referenced documents are indispensable for the application of this standard. For dated reference, only the edition cited applies. For undated references, the latest edition (including any amendment) applies.
GB/T 4208 Degrees of protection provided by enclosure (IP code)
GB/T 19056 Vehicle travelling data recorder
GB/T 19951-2005 Road vehicles — Test methods for electrical disturbances from electrostatic discharge
GB/T 21437.2-2008 Road vehicles — Electrical disturbances from conduction and coupling — Part 2: Electrical transient conduction along supply lines only
GB/T 21437.3-2012 Road vehicles — Electrical disturbances from conduction and coupling — Part 3: Electrical transient transmission by capacitive and inductive coupling via lines other than supply lines
GB/T 28046.1 Road vehicles — Environmental conditions and testing for electrical and electronic equipment — Part 1: General
GB/T 28046.3-2011 Road vehicles — Environmental conditions and testing for electrical and electronic equipment — Part 3: Mechanical loads
JT/T 617.5 Regulations concerning road transportation of dangerous goods — Part 5: Consignment
JT/T 766-2009 Technical requirements for shipborne monitoring equipment of BeiDou navigation satellite system
JT/T 825 IC card license for road transportation
QC/T 1067.1 Connector used in automobile wire harness and electrical device — Part 1: Definition, test method and requirement
GB/T 31465.3 Road vehicles — Fuse-link — Part 3: Fuse-link with blade type
QC/T 414 Design rule of color and type code for automotive cables
YD/T 1050 Test Specification for 800 MHz CDMA Digital Celluar Mobile Telecommunication Network: Terminal Part
YD/T 1214 Technical requirement of 900/1800MHz TDMA Digital Cellular Mobile Telecommunication Network General Packet Radio Service (GPRS) Equipment: Mobile Stations
YD/T 1367 Technical requirements for user equipment of 2GHzTD-SCDMA digital cellular mobile communication network
YD/T 1547 Technical requirements for 2GHz WCDMA digital cellular mobile communication network user equipment (Phase 3)
YD/T 1558 Technical Requirements of mobile station for 800MHz/2GHz cdma2000 digital cellular mobile telecommunication network
YD/T 2575 Technical requirements for user equipment of TD-LTE digital cellular mobile telecommunications network (Phase 1)
YD/T 2577 Technical requirements for user equipment of LTE-FDD digital cellular mobile telecommunications network (Phase 1)
3 Terms, definitions and abbreviations
3.1 Terms and definitions
For the purpose of this document, the following terms and definitions apply.
3.1.1
firmware
embedded software running in the terminal microprocessor
3.1.2
electronic travel permit
electronic data including vehicle, passenger and cargo information
3.1.3
start time of travelling
time that the state of vehicle changes from stationary to travelling (at a speed of more than 0 km/h for more than 10 s)
3.1.4
effective parking
action during which the state of vehicle changes from stationary to travelling (at a speed of 0 km/h) for at least 20 min
3.1.5
single continuous driving time
duration from the start time of the travelling till the start time of effective parking for the same driver
3.1.6
cumulative driving time
sum of single continuous driving time of the same driver within 24 h
3.1.7
monitoring centre
software platform for monitoring vehicle road transport
3.1.8
sleep
special state that the terminal remains in contact with the monitoring centre after the vehicle stalls
3.2 Abbreviations
For the purposes of this document, the following abbreviations apply.
CAN——Controller Area Network
IMEI——International Mobile Equipment Identity
GSM——Global System for Mobile Communication
CDMA——Code Division Multiple Access
TD-SCDMA——Time Division-Synchronous Code Division Multiple Access
WCDMA——Wideband Code Division Multiple Access
CDMA2000——Code Division Multiple Access 2000
TD-LTE——Time Division-Long Term Evolution
FDD-LTE——Frequency Division Duplexing-Long Term Evolution
LTE-V2X——Long Term Evolution-Vehicle to Everything
JPEG——Joint Photographic Experts Group
ETC——Electronic Toll Collection
4 General requirements
4.1 Composition of vehicle terminal
4.1.1 Host
The host of vehicle terminal [hereinafter referred to as the "terminal"] shall include microprocessor, data memory (capacity: not less than 8 GB), satellite positioning module, vehicle state information acquisition module, wireless communication module, real-time clock, data acquisition interface, which may include display, printer and card reader. If the terminal has display, printer, card reader which are not included in the host, they can be listed as accessory devices, but the host shall maintain corresponding interfaces.
4.1.2 Accessory device
External devices shall include satellite positioning antenna, wireless communication antenna, emergency alarm button and voice broadcasting device. According to the basic functional requirements of different categories of vehicles in Annex A, such devices include communication devices, operation keys, card readers, printers, displays, vehicle operation status information display, information release and other devices, as well as information acquisition devices for images, videos, audio, driver's identity, electronic travel permit, logistics, operation, toll settlement and service evaluation, etc.
4.2 Appearance
The appearance of terminals shall be free of rust, rust spots, cracks, fading, stains, deformation, peeling of plating and coating, obvious scratches or burrs; the plastic parts shall be free of blistering, cracking or deformation; the structural parts and control components shall be complete and free from mechanical damage.
4.3 Nameplate
Terminals shall have a nameplate with clear and durable markings. The nameplate shall be mounted in an obvious position on the outer surface of the host, and the size of the nameplate shall be suitable for the structural size of the host.
The nameplate shall bear the following information:
a) product name, specification and model;
b) name and trademark of terminal manufacturer;
c) end of-manufacturing date and number;
d) implementation standard reference to terminals;
e) terminal IMEI No.
4.4 Characters, graphics and markings
The terminals shall be provided with instructions for use. The buttons, interfaces and other parts of the panel shall be provided with characters, graphics and other markings, and meet the following requirements:
a) Durable and eye-catching;
b) The characters in the instructions for use, nameplates and markings shall be in Chinese, which may be accompanied with other languages as necessary. In that case, make sure Chinese characters are on the top or left side of other languages.
4.5 Material
The material shall meet the requirements of non-toxicity and non-radioactivity.
4.6 Casing protection
When the host does not contain display, printer or card reader, the casing shall be protected as required by IP53 in GB/T 4208; when the host includes display, printer, card reader and other devices or one of them, the casing shall be protected as required by IP43 in GB/T 4208; the casing of trailer terminals shall be protected as required by IP67 in GB/T 4208.
5 Functional requirements
5.1 Self-test
The terminals shall have self-test function, and shall be able to clearly indicate its current main state through signal lamp or display screen, including the working state of satellite positioning and communication modules, the state of main power supply, the state of satellite positioning antenna, and the state of other devices connected with the terminal host. The terminal shall be able to perform self-test at the preset frequency, which should be set by the monitoring centre. In case of failure, information such as failure types shall be indicated by signal lamp or display screen, stored and uploaded to the monitoring centre.
5.2 Positioning
5.2.1 Positioning function
The positioning function of terminals includes the followings:
a) The terminals shall be able to provide real-time positioning status information such as time, longitude, latitude, speed, elevation and direction, which can be stored inside the terminals and uploaded to the monitoring centre through wireless communication, with the differential positioning function optional;
b) The terminals that support multiple satellite positioning modes shall be able to upload the current positioning mode and support positioning based on the satellite positioning mode designated by the monitoring centre;
c) The terminal shall be able to store not less than 10,000 pieces of positioning data in a first-in-first-out (FIFO) mode when communication is interrupted (in blind zone), and upload the stored positioning data after communication is resumed, if needed, in a compressed mode;
d) The terminals shall support uploading positioning data at an interval of time or distance, or in external event triggering mode. When the terminal is in sleep state, the terminal shall also upload positioning data at a certain interval of time or distance that may be set by the monitoring centre;
e) The terminals using BeiDou satellite positioning shall have BeiDou satellite information collection function, and shall store and report BeiDou positioning results and detailed positioning data of satellite positioning module to the monitoring centre, which should at least include signal-to-noise ratio and effective number of satellites;
f) The terminals using BeiDou satellite positioning shall be able to respond to two instructions issued by the monitoring centre, i.e. adding BeiDou information acquisition area and deleting BeiDou information acquisition area;
g) The terminals using BeiDou satellite positioning shall be able to store at least 24 rectangular areas for satellite information acquisition issued by monitoring centre. When the vehicle enters a certain rectangular area, the function of satellite signal acquisition is automatically started and uploaded at a specified frequency, and the acquisition and uploading are automatically stopped when it leaves the area;
h) The terminals using BeiDou satellite positioning shall be able to store or upload detailed positioning data such as current positioning mode and satellite signal coverage status information to the monitoring centre based on the parameter settings specified by the monitoring centre. The terminals can store at least 2,000 pieces of detailed positioning data. If the stored data exceeds the maximum capacity, the first stored data shall be discarded in temporal sequence;
i) Online upgrade and local upgrade functions of BeiDou and other GNSS satellite dual-mode positioning modules shall be supported.
5.2.2 Technical requirements for positioning
The positioning function of terminals shall meet the following technical requirements:
a) Submission at regular time interval: In the travelling state, the minimum time interval of submission is not more than 5 s, and the maximum time interval is not more than 30 s;
b) Submission at regular distance interval: In the travelling state, the minimum distance interval of submission is not more than 100 m, and the maximum distance interval is not more than 500 m;
c) Submission at regular time and distance interval: In the travelling state, the terminal can submit positioning data at the time and distance interval set by the monitoring centre;
d) Real-time positioning: The period is not more than 10 s from the terminal receiving the real-time positioning request from the monitoring centre till the terminal responding;
e) Accuracy of recording time: The permissible error of cumulative time within 24 h is within ±5 s.
5.3 Communication
5.3.1 Communication mode
The terminals shall support general CSM or CDMA mode, and can support communication modes based on TD-SCDMA, WCDMA, CDMA2000, TD-LTE, FDD-LTE, LTE-V2X and other wireless communication networks and the transmission mechanism of BeiDou Navigation Satellite System (BDS) as required. When the wireless network where the vehicle is located supports packet data transmission, the terminal shall give priority to the packet data transmission mode; otherwise, it may switch to short message mode to transmit data. When the wireless communication network cannot be connected, BeiDou communication mode may be used as needed.
5.3.2 Communication requirements
The communication requirements for terminals shall include the followings:
a) The terminals shall support at least two remote connections, namely, the connection between the main monitoring centre and the backup monitoring centre, and shall automatically switch to the backup monitoring centre when the communication with the main monitoring centre is interrupted;
b) If the terminals are unable to access the local wireless network, the data shall be stored in a FIFO mode and transmitted together until registering to the wireless network;
c) The terminals shall support the functions of receiving and sending data in batches and continuous transmission of breakpoints;
d) Encryption measures should be taken for communication between terminal and monitoring centre.
5.4 Information acquisition
5.4.1 Driver’s identity
The driver identification device of the terminal shall meet the requirements of JT/T 825, and support acquiring the qualification certificate information through remote authentication after encryption and uploading it to the monitoring centre.
The terminals shall be able to automatically detect the action of replacing the driver's IC card qualification certificate, and realize the corresponding driver identification function.
5.4.2 Electronic travel permit
The electronic travel permit for dangerous goods transport shall meet the requirements of JT/T 617.5, and the terminals shall be able to receive the electronic travel permit information sent to the terminals by the dangerous goods transport enterprise through encryption or digital identity authentication.
5.4.3 Vehicle CAN bus data
A terminal shall have two built-in CAN bus communication interfaces, and acquire information on vehicle running state through CAN bus.
5.4.4 Vehicle loading state
The terminals can be provided with the interface of vehicle loading state detection device; alternatively, the vehicle loading state can be determined by manual input and uploaded to the monitoring centre.
5.4.5 Toll settlement data
The terminal can be provided with an interface of toll settlement data acquisition device, which supports acquiring toll settlement information and uploading it to the monitoring centre.
5.4.6 Image information
The terminals can be provided with the functions of image information acquisition and storage; support the functions of image information acquisition, storage, uploading, retrieval & uploading through the control of monitoring centre, timing and event triggering; and support the export of image information through USB interface. Image information acquisition shall meet the following requirements:
a) It supports at least two cameras;
b) The cameras support infrared light supplement;
c) It sets at least two imaging resolutions, with the highest resolution of not less than 720P and the lowest of not less than D1;
d) The minimum acquisition interval is 5 s;
e) The current date and time can be displayed in the image (24-hour time system) in the format of yyyy-mm-dd hh: mm: ss;
f) It supports the storage of images in JPEG format at least;
g) It stores at least 2,000 images in a FIFO mode;
h) It supports marking the image data, which shall not be overwritten.
5.4.7 Video information
The terminals can be provided with the functions of video information acquisition and storage; support the functions of image information acquisition, compression, storage, uploading, retrieval & uploading through the control of monitoring centre and event triggering; support the real-time uploading of video data; and support the export of video data through local data interface. Video information acquisition shall meet the following requirements:
a) Support at least two cameras;
b) It can set at least two imaging resolutions, with the highest resolution of not less than 720P;
c) The frame rate of locally stored video is not less than 25 FPS, and the frame rate of uploaded video is not less than 15 FPS;
d) The current date and time can be displayed in the video (24-hour time system) in the format of yyyy-mm-dd hh: mm: ss;
e) The video acquisition coding format is H.264 or H.265;
f) It can store at least 48 h of video data;
g) It supports marking the video data, which shall not be overwritten.
5.4.8 Vehicle state information
The terminal shall support acquiring information such as switch quantity and analog quantity of the vehicle, including braking, left steering, right steering, passing beam and driving beam. At least 5 switch quantities and 2 analog quantities shall be acquired, and the acquired information shall be uploaded to the monitoring centre together with the positioning data.
5.5 Travelling data record
The terminals shall have the function of automobile travelling data record, and provide data analysis software, which supports the functions of real-time uploading of travelling data record, conditional retrieval uploading and data interface export. The data analysis software, function of terminal travelling data record and storage performance shall meet the requirements of GB/T 19056.
5.6 Monitoring
The terminals may have the function of monitoring through the circuit domain or data link, and the speaker shall be turned off when monitoring. When monitoring through the circuit domain, the following requirements shall be met:
a) After the monitoring centre sends the monitoring instruction, the terminals automatically dial the monitoring number carried by the monitoring instruction to enter the monitoring state;
b) Save data to be uploaded during monitoring and upload it after monitoring;
c) In the case of manual alarm, terminals without image, audio and video acquisition functions automatically dial a preset monitoring number to enter the monitoring state;
d) When the terminals dial the monitoring number, dial another three times at an interval of 30 s, in the case of not getting through for the first time.
5.7 Calls
The terminals can provide calls through circuit domain or data link, including call restriction, voice storage, telephone directory management, telephone callback, volume adjustment, and automatic off-hook of incoming calls. The function of terminal call shall meet the following requirements:
a) The data to be uploaded shall be saved for a call through circuit domain, and uploaded after the call is ended;
b) The terminal telephone directory shall be provided with a storage capacity of not less than 20 contacts;
c) The terminal may be set by the monitoring centre to allow only incoming calls and only outgoing calls.
5.8 Sleep
The terminal shall be provided with the function of vehicle start-up detection (except trailer terminals). One hour after the vehicle stalled, the terminal sends a terminal sleep signal to the monitoring centre, enters the sleep state, and ends the sleep state after the next start-up. The terminal in sleeping shall meet the following requirements:
a) Turn off other unnecessary devices except the wireless communication module, and automatically wake the satellite positioning module when uploading is required;
b) The data upload frequency may be remotely set by the monitoring centre or automatically and continuously reduced according to the parameters set during initialization;
c) After the battery undervoltage alarm, the terminal turns to the built-in standby battery for power supply, and automatically powers off when the built-in standby battery is run out;
d) The average power of the terminal during the sleep period does not exceed 1.5 W.
5.9 Warning
5.9.1 General requirements
When the terminal triggers the warning, it shall immediately upload the warning information to the monitoring centre or send the short message about warning information to the designated mobile phone as needed, and can receive the instruction from the monitoring centre to cancel the warning. The warning mobile phone number may be set remotely by the monitoring centre. When the monitoring centre sends instructions to the terminal based on the vehicle position, state information or safety supervision needs uploaded by the vehicle, the terminal shall prompt the driver about the warning information by voice broadcasting, which may be combined with sound, light and text. Terminal warning function includes two parts, manual alarm and automatic reminder.
5.9.2 Manual alarm
Manual alarm is triggered by the driver according to the actual situation on site. When encountering emergency including robbery, traffic accident and vehicle breakdown, the driver uploads alarm information to the monitoring centre by touching the emergency alarm button, while turning off the voice broadcasting module. If the terminal is provided with the image and video acquisition function, it shall be enabled immediately. Where there is no mobile communication signal, the terminal with BDS communication function may upload alarm information by sending send short message through the system. Manual alarm shall be provided with the function of preventing misoperation.
5.9.3 Automatic reminder
Automatic reminder means that the driver does not operate the terminal, and it is triggered according to the conditions set by the monitoring centre, including the following functions:
a) Area reminder: There shall not be less than 24 polygonal or circular areas stored in the terminal. And the reminder will be triggered when the vehicle enters or exits the forbidden areas, and the monitoring area may be set remotely by the monitoring centre.
b) Reminder about restricted period: It may be triggered in the terminal according to the preset restricted period or by receiving the information sent by the monitoring centre to warn the driver that he or she is currently driving in the restricted period. The default restricted period is 2:00 am to 5:00 am.
c) Route deviation reminder: There shall not be less than 24 routes stored in the terminal, and each route shall be a broken line covering 16 or more points. It will be triggered when the vehicle deviates from the set route, and the route to be monitored may be set remotely by the monitoring centre.
d) Overspeed reminder: The terminal shall trigger the reminder according to the preset speed threshold or by receiving the information from the monitoring centre.
e) Drowsy driving reminder: It is triggered when the single continuous driving time and cumulative driving time exceed the drowsy driving time threshold, which may be set remotely by the monitoring centre. The default single continuous driving time is 4 h, and the default cumulative driving time is 8 h.
f) Battery under-voltage reminder: It is triggered when the terminal detects that the battery voltage of the vehicle is lower than the preset value. At the same time, the terminal must stop tapping into the power supply from the vehicle battery but turn to the built-in standby battery for power supply.
g) Power-off reminder: It is triggered when the main power supply for the terminal is turned off.
h) Antenna disconnection reminder: It is triggered when the terminal satellite positioning antenna is cut.
i) Overtime parking reminder: It is triggered when the parking time exceeds the preset duration in the system.
j) Terminal fault reminder: It is triggered when the terminal host and the external devices connected with the terminal host work abnormally, and uploaded to the monitoring centre.
k) Tyre pressure abnormality reminder: Communication between the terminal and the vehicle tyre pressure monitoring system is available, and the terminal can receive and upload information about the tyre pressure abnormality reminder.
l) Rollover reminder: It is triggered when the vehicle is rolled over.
m) Collision reminder: It is triggered when there is a collision accident.
n) Unsafe driving behavior reminder: Communication between the terminal and the system of monitoring on driver's unsafe driving behavior is available, and the terminal receives and uploads the reminder information about the driver's unsafe driving behavior, e.g., smoking, speaking on the phone, distraction and dozing off.
o) Right-turning blind zone abnormality reminder: Communication between the terminal and the right-turning blind zone monitoring system is available. When the vehicle turns right, whereas there are pedestrians, non-motor vehicles or other motor vehicles in the right-turning blind zone, the terminal receives and uploads the information.
Contents of JT/T 794-2019/XG1-2021
Foreword i
1 Scope
2 Normative references
3 Terms, definitions and abbreviations
4 General requirements
5 Functional requirements
6 Performance requirements
7 Installation requirements
8 Inspection rules
Annex A (Normative) Basic functional requirements of various transport vehicle terminals
JT/T 794-2019/XG1-2021, JT 794-2019/XG1-2021, JT 794-2019XG1-2021, JT/T794-2019/XG1-2021, JT/T 794, JT/T794, JT794-2019/XG1-2021, JT 794, JT794, JT794-2019XG1-2021, JT 794, JT794
