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GB/T 20851.5-2007: [including 2012XG] Electronic toll collection -- Dedicated short range communication -- Part 5: Test methods of the main parameters in physical layer Delivery: 9 seconds. True-PDF full-copy in English & invoice will be downloaded + auto-delivered via email. See step-by-step procedure Status: Obsolete GB/T 20851.5: Historical versions
Similar standardsGB/T 20851.5-2007: [including 2012XG] Electronic toll collection -- Dedicated short range communication -- Part 5: Test methods of the main parameters in physical layer---This is an excerpt. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.), auto-downloaded/delivered in 9 seconds, can be purchased online: https://www.ChineseStandard.net/PDF.aspx/GBT20851.5-2007 GB NATIONAL STANDARD OF THE PEOPLE’S REPUBLIC OF CHINA ICS 35.100.10 L 79 Electronic toll collection - Dedicated short range communication- Part 5.Test methods of the main parameters in physical layer Issued on: MARCH 19, 2007 Implemented on: MAY 1, 2007 Issued by. General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China; Standardization Administration of the People’s Republic of China. Table of ContentsForeword... 3 1 Scope... 4 2 Normative references... 4 3 Symbols and abbreviations... 4 4 Main test equipment and recommended characteristics of accessories... 5 5 Test conditions... 7 6 Test methods... 8 Attachment... 14ForewordGB/T 20851-2007 Electronic toll collection - Dedicated short range communication is divided into. — Part 1.Physical payer; — 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 is part 5 of GB/T 20851-2007. This Part was proposed by Ministry of Transport. This Part shall be under the jurisdiction of National Technical Committee (SAC/TC 268) on Intelligent Transportation System (ITS) of Standardization Administration of China. Drafting organization of this Part. Highway Research Institute of Ministry of Transport. Main drafters of this Part. Wang Xiaojing, Xiao Di, Yang Yun, Chen Bingxun, and Zhong Chongbo. Electronic Toll Collection - Dedicated Short Range Communication - Part 5.Test Methods of the Main Parameters in Physical Layer1 ScopeThis Part specifies the main test equipment of main parameters in physical layer of electronic toll collection (ETC) - dedicated short range communication (DSRC), and recommended characteristics, test conditions and test methods of accessories. This Part is applicable to the test of main parameters of the physical layer of electronic toll collection - dedicated short range communication roadside unit (RSU) and on-board unit (OBU). This Part is applicable to highways and city roads’ electronic toll collection system. Fields such as automatic vehicle identification, vehicle access management may reference to this Part for the use.2 Normative referencesThe articles contained in the following documents have become articles of this Part of GB/T 20851 when they are quoted herein. For the dated documents so quoted, all the modifications (excluding corrections) or revisions made thereafter shall not be applicable to this Part. For the undated documents so quoted, the latest editions shall be applicable to this Part. GB 9254-1998 Information technology equipment - Radio disturbance characteristics - Limits and methods of measurement (idt CISPR 22.1997) GB/T 12190-2006 Method for measuring the shielding effectiveness of electromagnetic shielding enclosures GB/T 20851.1-2007 Electronic toll collection - Dedicated short range communication - Part 1.Physical layer3 Symbols and abbreviations3.1 Symbols Following symbols apply to this Part. dBc refers to the ratio of power to carrier signal power dBm refers to the ratio of power to 1mW, 0 dBm = 1mW e.i.r.pcon refers to spurious equivalent isotropic radiated power e.i.r.pmax refers to maximum equivalent isotropic radiated power fc refers to center frequency of signal source transmitted signal fTx refers to nominal carrier frequency fTxa refers to actual carrier frequency GT refers to test antenna gain GRx refers to receiving antenna gain of device under test GTx refers to transmitting antenna gain of device under test m refers to modulation index Pcon refers to spurious emission power Pcw refers to single-frequency signal power of device under test Pcwo refers to signal source and single-frequency signal power of test antenna Po refers to signal source output power ∆f refers to carrier frequency error 3.2 Abbreviations Following abbreviations apply to this Part DSRC Dedicated Short Range Communication ETC Electronic Toll Collection OBU On Board Unit RBW Resolution Band Width RSU Roadside Unit VSWR Voltage Standing-Wave Ratio4 Main test equipment and recommended characteristics ofaccessories 4.1 Power meter — Power measurement range. -60 dBm ~ +20 dBm; — Frequency range. 10 MHz~18 GHz; — Power measurement error. ±3%. 4.2 Frequency meter — Frequency range. 10 Hz~+20 GHz； — Frequency measurement error. ±10 x 10-9. 4.3 Microwave signal source — Frequency range. 250 kHz~20 GHz; — Frequency accuracy. fc x 10 x 10-9; — Phase noise. Less than -98 dBc/Hz@10 GHz, 1 kHz bias. 4.4 Spectrum analyzer — Frequency range. 3 Hz~26.5 GHz; — Dynamic range. Not less than 70 dB; — Resolution bandwidth. 10 Hz~3 MHz; — Background noise. Not greater than -140 dBm/Hz. 4.5 Vector signal analyzer — Frequency range. DC~6 GHz； — Vector modulation analysis type. Amplitude modulation, frequency modulation and phase modulation analysis. 4.6 Digital oscilloscope — Bandwidth. 1 GHz; — Sampling rate. 2 Gsa/s; — Memory depth. 2 M points for each channel; 6.4.1 Conduction test 6.4.1.1 Test equipment Power meter. 6.4.1.2 Test steps Test steps are as follows. a) Set the operating frequency of transmitter of device under test; set device under test in a non-modulation state, i.e. carrier state; b) Set transmitting frequency of device under test to the maximum value; c) Use power meter to measure power Pcw of transmitting antenna port of device under test; calculate corresponding equivalent isotropic radiated power, in dBm; computational formula. e.i.r.pmax = Pcw X GTx Repeat the above steps to measure equivalent isotropic radiated power at other carrier frequencies. 6.4.2 Radiation test 6.4.2.1 Test equipment Power meter, microwave signal source. 6.4.2.2 Test steps Test steps are as follows. a) Set the operating frequency of transmitter of device under test; test the device under test in a non-modulation state, i.e. carrier state; a) Set the transmitting power of device under test to the maximum value; b) Use power meter to measure the power Pcw; c) Under the same test conditions, use microwave signal and test antenna of known gain GT to replace the device under test, and use power meter to measure power Pcwo; adjust the output power of microwave signal source, until Pcwo is equal to Pcw; d) Adjust corresponding equivalent isotropic radiated power, in dBm; computational formula. e.i.r.pmax = Po X GT frequency bands, until the power measured by spectrum analyzer is equal to Pcon; f) Calculate spurious emission e.i.r.pcon at corresponding frequency bands, in dBm; computational formula. e.i.r.pcon = Po X GT Repeat above steps to measure spurious emissions of frequency bands at other carrier frequencies. 6.6 Modulation mode and modulation index 6.6.1 Test equipment Vector signal analyzer. 6.6.2 Test steps This test may be completed at radiation or conduction test conditions. Test steps are as follows. a) Set the operating frequency of transmitter of device under test; set the device under test in a state of continuous emission of test signal; b) Set transmitting power of device under test to the maximum value; c) Set modulation index of device under test to the minimum value within its allowable range; d) Use vector signal analyzer to measure the modulation index of device under test; e) Change the operation frequency of transmitter of device under test; measure the modulation index at other carrier frequencies; f) Set modulation index of device under test to the maximum value within its allowable range; g) Use vector signal analyzer to measure the modulation index of device under test; h) Change the operating frequency of transmitter of device under test; the remaining settings are unchanged; test the modulation index under other carrier frequencies. 6.7 Bit rate 6.7.1 Test equipment Digital oscilloscope. 6.7.2 Test steps Attachment. GB/T 20851.5-2007 “Electronic toll collection - Dedicated short range communication- Part 5.Test methods of the main parameters in physical layer” National Standard No. 1 Amendment The contents in Chapter 1 "This Part is applicable to the test of main parameters of the physical layer of electronic toll collection dedicated short range communication road side unit (RSU) and on-board unit (OBU)” is change to be "This Part is applicable to highways and city roads electronic toll collection system. Fields such as automatic vehicle identification, vehicle access management may reference to this Part for the use”. ......Source: Above contents are excerpted from the full-copy PDF -- translated/reviewed by: www.ChineseStandard.net / Wayne Zheng et al. |
