GB/T 20851.1-2019 (GBT20851.1-2019)

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GB/T 20851.1-2019	English	135	Add to Cart	0--9 seconds. Auto-delivery	Electronic toll collection -- Dedicated short range communication -- Part 1: Physical layer	GB/T 20851.1-2019	Valid	GB/T 20851.1-2019

GB/T 20851.1-2019
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 35.100.10
L 79
Replacing GB/T 20851.1-2007
Electronic Toll Collection – Dedicated Short Range
Communication – Part 1: Physical Layer
ISSUED ON: MAY 10, 2019
IMPLEMENTED ON: DECEMBER 01, 2019
Issued by: State Administration for Market Regulation;
Standardization Administration of PRC.
Table of Contents
Foreword ... 3
1 Scope ... 5
2 Normative References ... 5
3 Terms and Definitions ... 5
4 Signs and Abbreviations ... 6
5 Basic Requirements ... 7
6 Downlink Technical Requirements ... 7
7 Uplink Technical Requirements ... 8
Bibliography ... 10
Foreword
GB/T 20851 Electronic Toll Collection – Dedicated Short Range Communication can
be divided into the following 5 parts:
--- Part 1: Physical Layer;
--- Part 2: Data Link Layer;
--- Part 3: Application Layer;
--- Part 4: Equipment Application;
--- Part 5: Test Methods of the Main Parameters in Physical Layer.
This Part belongs to Part 1 of GB/T 20851.
This Part was drafted as per the rules specified in GB/T 1.1-2009.
This Part replaced GB/T 20851.1-2007 Electronic Toll Collection – Dedicated Short
Range Communication – Part 1: Physical Layer. Compared with GB/T 20851.1-2007,
this Part has the major technical changes as follows besides the editorial modification:
--- Modify the downlink technical requirements; transfer the contents of “downlink”
into “downlink technical requirements” (see Clause 6 of this Edition; 5.2 of 2007
Edition);
--- Add the provisions on the indicators such as downlink antenna sidelobe level,
antenna front-to-rear ratio, 14kHz square wave wake-up signal accuracy, OBU
maximum input signal power, OBU co-channel interference rejection ratio, OBU
adjacent channel interference rejection ratio, OBU blocking interference rejection
ratio, etc. (see Clause 6 of this Edition);
--- Modify the provisions of the indicators such as downlink modulation factor, OBU
receiving bandwidth, preamble, etc. (see Clause 6 of this Edition; 5.2 of 2007
Edition);
--- Modify the uplink technical requirements; transfer the contents of “uplink” into
“uplink technical requirements” (see Clause 7 of this Edition; 5.3 of 2007 Edition);
--- Add the provisions of indicators such as uplink RSU maximum input signal power,
RSU co-channel interference rejection ratio, RSU adjacent channel interference
rejection ratio, RSU blocking interference rejection ratio, RSU receiving
bandwidth, etc. (see Clause 7 of this Edition);
--- Modify the provisions of indicators such as uplink adjacent channel leakage
Electronic Toll Collection – Dedicated Short
Range Communication – Part 1: Physical Layer
1 Scope
This Part of GB/T 20851 specifies the basic requirements for the physical layer of
dedicated short-range communication of electronic toll collection, as well as the
downlink and uplink technical requirements.
This Part is applicable to the electronic toll collection system on the highway and city
road; while the automatic vehicle identification, vehicle access management, and the
like fields can use for reference.
2 Normative References
The following documents are essential to the application of this document. For the
dated documents, only the versions with the dates indicated are applicable to this
document; for the undated documents, only the latest version (including all the
amendments) are applicable to this document.
GB/T 9410-2008 General Specification for Antennas Used in the Mobile
Communications
GB/T 13622-2012 Terminology for Radio Regulation
GB/T 14733.7-2008 Terminology for Telecommunication – Oscillations, Signals
and Related Devices
GB/T 14733.9-2008 Terminology for Telecommunication - Radio Wave
Propagation
GB/T 20839-2007 Intelligent Transport Systems - General Terminology
3 Terms and Definitions
For the purposes of this Document, the terms and definitions given in GB/T 9410-2008,
GB/T 13622-2012, GB/T 14733.7-2008, GB/T 14733.9-2008 and GB/T 20839-2007
and the following apply.
3.1 Wakeup
The process in which the on-board unit (OBU) transmitting from a sleep state to an
active state.
3.2 Preamble
The advance signal of the physical layer frame information, irrelevant to the link layer,
may be a modulated or unmodulated carrier wave.
3.3 Post-amble
The post signal of the physical layer frame information, irrelevant to the link layer, may
be a modulated or unmodulated carrier wave.
4 Signs and Abbreviations
4.1 Signs
The following signs are applicable to this document.
dBm: characterize the ratio of power and 1mW.
RSUt: Roadside Unit Transmitting Antenna.
RSUr: Roadside Unit Receiving Antenna.
4.2 Abbreviations
The following abbreviations are applicable to this document.
ASK: Amplitude Shift Keying
BER: Bit Error Rate
e.i.r.p: equivalent isotropically radiated power
ETC: Electronic Toll Collection
FSK: Frequency Shift Keying
OBU: On Board Unit
RSU: Roadside Unit
XPD: Cross Polarization Discrimination