标准编号:	GB/T 20851.5-2019
中文名称:	电子收费 专用短程通信 第5部分:物理层主要参数测试方法
英文名称:	Electronic toll collection—Dedicated short range communication—Part 5:Test methods of the main parameters in physical layer
中标分类:	L79    计算机开放与系统互连
行业分类:	GB    国家标准
ICS分类:	35.100.10 35.100.10    物理层 35.100.10
发布机构:	国家市场监督管理总局 国家标准化管理委员会
发布日期:	2019-05-10
实施日期:	2019-12-1
标准状态:	现行
替代旧标准:	GB/T 20851.5-2007 电子收费 专用短程通信 第5部分：物理层主要参数测试方法 GB/T 20851.5-2007/XG1-2012 《电子收费 专用短程通信 第5部分：物理层主要参数测试方法》国家标准第1号修改单
翻译语言:	英文
文件格式:	PDF
中文字符数:	25000 字
翻译价格(元):	850.00 元
交付时间:	付款后 1 个工作日

GB/T 20851 consists of the following five parts under the general title Electronic toll collection - Dedicated short range communication:



——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 is part 5 of GB/T 20851.



This part is developed in accordance with the rules given in GB/T 1.1-2009.



This part replaces GB/T 20851.5-2007 Electronic toll collection - Dedicated short range communication - Part 5: Test methods of the main parameters in physical layer. In addition to editorial changes, the following main technical changes have been made with respect to GB/T 20851.5-2007:



——the test signal requirements are modified and added (see 5.2; 5.2 of Edition 2007);



——"Requirements for test state of equipment under test" is added (see 5.3);



——the expressions of test methods are modified (see 6.2, 6.3 and 6.4; 6.2, 6.3, 6.4, 6.5, 6.6, 6.7 and 6.8 of Edition 2007);



—— the test methods for receiving sensitivity, receiving bandwidth, maximum input signal power, cochannel interference rejection ratio, adjacent channel interference rejection ratio and blocking interference rejection ratio of roadside unit are added (see 6.2);



——the test methods for wakeup sensitivity, wakeup time, receiving sensitivity, receiving bandwidth, maximum input signal power, cochannel interference rejection ratio, adjacent channel interference rejection ratio and blocking interference rejection ratio of on board unit are added (see 6.3);



——the test method of initialization equipment for on board unit is modified and added (see 6.4; 6.4 of Edition 2007).



This part was proposed by and is under the jurisdiction of the National Technical Committee on Intelligent Transportation Systems of Standardization Administration of China (SAC/TC 268).



The previous edition replaced by this part is as follows:



——GB/T 20851.5-2007.

Electronic toll collection - Dedicated short range communication - Part 5: Test methods of the main parameters in physical layer



1 Scope



This part of GB/T 20851 specifies the recommended characteristics, test conditions and test methods of the main test equipment and accessories for the main parameters in physical layer of dedicated short range communication for electronic toll collection.



This part is applicable to electronic toll collection system for highways and urban roads, and may be used as a reference for fields of automated vehicle identification, vehicle access control system, etc.



2 Normative references



The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.



GB/T 9254 Information technology equipment - Radio disturbance characteristics - Limits and methods of measurement

GB/T 12190-2006 Method for measuring the shielding effectiveness of electromagnetic shielding enclosures

GB/T 20851.1-2019 Electronic toll collection - Dedicated short range communication - Part 1: Physical layer



3 Symbols and abbreviations



3.1 Symbols



For the purposes of this document, the following symbols apply.



D: the maximum diameter of antenna.



d: the distance between equipment under test and test antenna.



dBc: the ratio of representation power to carrier signal power.



dBm: the ratio of representation power to 1mW.



e.i.r.pcon: the spurious equivalent isotropically radiated power.



e.i.r.pmax: the maximum equivalent isotropically radiated power.



f1: the lower limit frequency of receiving bandwidth.



f2: the upper limit frequency of receiving bandwidth.



fc: the center frequency of signal emitted by signal source.



fTx: the nominal carrier frequency.



fTxa: the actual carrier frequency.



GRx: the gain of receiving antenna of equipment under test.



GT: the gain of test antenna.



GTx: the gain of transmitting antenna of equipment under test.



h: the height of equipment under test and test antenna from the ground.



PA: the test signal power of adjacent channel interference.



PB: the test signal power of blocking interference.



PC: the test signal power of co-channel interference.



Pcon: the spurious emission power.



Pcw: the single frequency signal power of the equipment under test.



Pcwo: the single frequency signal power of signal source and test antenna.



Pi,max: the maximum input signal power.



P0: the output power of signal source.



PR: the measured power of the signal received by the test antenna replacing the equipment under test.



RA: the adjacent channel interference rejection ratio.



RB: the blocking interference rejection ratio.



RC: the cochannel interference rejection ratio.



SRx: the receiving sensitivity.



SW: the wakeup sensitivity.



T0: the start time of sending wake-up signal.



TR: the start time of sending response signal.



TW: the wakeup time.



Δf: the frequency tolerance.



λ: the wavelength.



3.2 Abbreviations



For the purposes of this document, the following abbreviations apply.



OBU: On Board Unit



RBW: Resolution Bandwidth



RSU: Roadside Unit



VSWR: Voltage Standing-Wave Ratio



4 Recommended characteristics of main test equipment and accessories



4.1 Power meter



The recommended characteristics of power meter shall meet the following requirements:



a) power measurement range: -60~+20dBm;



b) frequency range: 10MHz~18GHz;



c) power measurement error: ±3%.



4.2 Frequency meter



The recommended characteristics of the frequency meter shall meet the following requirements:



a) frequency range: 10Hz~20GHz;



b) frequency measurement error: ±10×10-9.



4.3 Microwave signal source



The recommended characteristics of microwave signal source shall meet the following requirements:



a) frequency range: 250kHz~20GHz;



b) frequency precision: fc×100×10-9;



c) phase noise: < -98dBc/Hz@10GHz, 1kHz offset.



4.4 Spectrum analyzer



The recommended characteristics of spectrum analyzer shall meet the following requirements:



a) frequency range: 3Hz~26.5GHz;



b) dynamic range: ≥70dB;



c) resolution bandwidth: 10Hz~3MHz;



d) background noise: ≤ -140dBm/Hz.



4.5 Vector signal analyzer



The recommended characteristics of vector signal analyzer shall meet the following requirements:



a) frequency range: direct current~6GHz;



b) vector modulation analysis type: amplitude modulation, frequency modulation and phase modulation analysis.



4.6 Digital oscilloscope



The recommended characteristics of digital oscilloscope shall meet the following requirements:



a) bandwidth: 1GHz;



b) sampling rate: 2Gsa/s;



c) memory depth: 2M points per channel;



d) trigger mode: edge, code pattern, time/event delay and pulse width, etc.



4.7 Test antenna



The recommended characteristics of the test antenna shall meet the following requirements:



a) frequency range: 30MHz~20GHz;



b) polarization mode: linear polarization;



c) VSWR: < 1.5:1;



d) impedance: 50Ω;



e) gain: available.



5 Test conditions



5.1 Test site and configuration



5.1.1 Test site



The radiation test may be conducted in anechoic chamber or open field.



The minimum dimension of anechoic chamber shall meet the test requirements in 3m method, the shielding effectiveness shall meet the requirements of GB/T 12190-2006, and the normalized site attenuation shall meet the requirements of GB/T 9254.



When tested in an anechoic chamber, the equipment under test shall be within the quiet zone of anechoic chamber.



The normalized site attenuation of open area shall meet the requirements of GB/T 9254.



5.1.2 Configuration



5.1.2.1 Configuration of conduction test system



The conduction test system consists of equipment under test, test equipment and connecting accessories, wherein, the connecting accessories include connectors, attenuators, etc. The connecting accessories are determined according to the interface of equipment under test and the strength of signal under test. Refer to Figure 1 for configuration of conduction test system.







Figure 1 Configuration of conduction test system



5.1.2.2 Configuration of radiation test system



The radiation test system consists of equipment under test, test equipment and connecting accessories, wherein, the connecting accessories include coaxial cable, test antenna, connector, attenuator, etc. The connecting accessories are determined according to the interface of equipment under test and the strength of signal under test. Refer to Figure 2 for configuration of radiation test system.







Figure 2 Configuration of radiation test system



The distance between equipment under test and test antenna, d, shall conform to Equation (1):



(1)



The height of equipment under test and test antenna from the ground, h, conform to Equation (2):



h≥4D (2)



5.2 Test signal



The test system shall provide the following test signals:



a) test signal for bit rate, which is FM0-coded all-zero code modulated at the working frequency point;



b) interference test signals for cochannel and adjacent channel interference rejection ratios, which are modulated and uncoded pseudo-random binary sequence (PN9) signals with a cycle of 511 bits;



c) interference test signal for blocking interference rejection ratio, which is the continuous wave signal at a fixed frequency point out of the working frequency band (5725MHz~5850MHz) by (30MHz~20GHz);



d) wakeup response signal of OBU, which is the carrier signal transmitted in corresponding channel and lasting for 20ms.



5.3 Requirements for test state of equipment under test



5.3.1 RSU



The RSU under test shall be able to receive and transmit test signals according to the requirements of 5.2 and test demands, i.e., it is able to continuously transmit carrier, PN9 code and FM0-coded all-zero code modulated at working frequency point, and also able to extract the demodulated received data and clock signal and provide test points.



5.3.2 OBU



The OBU under test shall be able to receive and transmit test signals according to the requirements of 5.2 and test demands, i.e., it is able to transmit carrier, PN9 code and FM0-coded all-zero code modulated at the working frequency point, and send wakeup response signal after wakeup, and also able to extract the demodulated received data and clock signal and provide test points.



5.3.3 Initialization equipment for OBU



The initialization equipment for OBU under test shall be able to receive and transmit test signals according to the requirements of 5.2 and test demands. i.e., it is able to continuously transmit carrier, PN9 code and FM0-coded all-zero code modulated at working frequency point, and also able to extract the demodulated received data and clock signal and provide test points.



6 Test methods



6.1 General



For items with conduction test capability during test, conduction test method should be adopted.



6.2 RSU test



6.2.1 Carrier frequency and frequency tolerance



6.2.1.1 Test equipment



Frequency counter or spectrum analyzer with counter is used as the equipment for carrier frequency and frequency tolerance tests.



6.2.1.2 Test steps



This test may be completed under conduction or radiation test conditions, of which the steps are as follows:



a) set the working frequency of the transmitter of the equipment under test and set the equipment under test in non-modulation state, i.e., carrier state;



b) measure the actual carrier frequency fTxa of the equipment under test with frequency meter or spectrum analyzer with counter;



c) calculate the frequency tolerance Δf of the carrier frequency using Equation (3):



∆f=|f_"Tx" -f_"Txa" |/(f_"Tx" ×10^6 ) (3)



d) repeat the above steps to test other carrier frequencies and their frequency tolerances.



6.2.2 Occupied bandwidth



6.2.2.1 Test equipment



Spectrum analyzer is used as the equipment for occupied bandwidth test.



6.2.2.2 Test steps



This test may be completed under conduction or radiation test conditions, of which the steps are as follows:



a) set the working frequency of the transmitter of the equipment under test and set the equipment under test in the state of continuously transmitting test signals;



b) set the transmitting power of the equipment under test to the maximum;



c) measure the occupied bandwidth of the test signal with spectrum analyzer;



d) repeat the above steps to measure the occupied bandwidth at other carrier frequencies.



6.2.3 Equivalent isotropically radiated power



6.2.3.1 Conduction test



6.2.3.1.1 Test equipment



Power meter is used as the equipment for conduction test of equivalent isotropically radiated power.



6.2.3.1.2 Test steps



Test steps are as follows:



a) set the working frequency of the transmitter of the equipment under test and set the equipment under test in non-modulation state, i.e., carrier state;



b) set the transmitting power of the equipment under test to the maximum;



c) use power meter to measure the power Pcw of transmitting antenna port of the equipment under test, and calculate the maximum equivalent isotropically radiated power e.i.r.pmax using Equation (4):



e.i.r.pmax=Pcw×GTx (4)



d) repeat the above steps to test the equivalent isotropically radiated power at other carrier frequencies.



6.2.3.2 Radiation test



6.2.3.2.1 Test equipment



The equipment for radiation test of equivalent isotropically radiated power includes power meter and microwave signal source.



6.2.3.2.2 Test steps



Test steps are as follows:



a) the same as 6.2.3.1.2 a);



b) the same as 6.2.3.1.2 b);



c) measure the power Pcw with power meter;



d) under the same test conditions, replace the equipment under test with a microwave signal source and a test antenna with known gain GT, measure the power Pcwo with a power meter, and adjust the output power P0 of the microwave signal source until Pcwo is equal to Pcw;



e) calculate the maximum equivalent isotropically radiated power e.i.r.pmax using Equation (5):



e.i.r.pmax=P0×GT (5)



f) the same as 6.2.3.1.2 d).



6.2.4 Spurious emission



6.2.4.1 Conduction test



6.2.4.1.1 Test equipment



spectrum analyzer is used as the equipment for conduction test of spurious emission.



6.2.4.1.2 Test steps



Test steps are as follows:



a) set the working frequency of the transmitter of the equipment under test and set the equipment under test in the state of continuously transmitting test signals;



b) set the transmitting power of the equipment under test to the maximum;



c) set the modulation factor of the equipment under test to the maximum within its allowable range;



d) set RBW of spectrum analyzer in each test frequency band respectively and measure the spurious emission power Pcon of this frequency band, as required by Clauses 6 and 7, CB/T 20851.1-2019;



e) calculate the spurious equivalent isotropically radiated power e.i.r.pcon of this frequency band using Equation (6):



e.i.r.pcon=Pcon×GTx (6)



f) repeat the above steps to measure the spurious emissions at other carrier frequencies.



6.2.4.2 Radiation test



6.2.4.2.1 Test equipment



The equipment for radiation test of spurious emission includes spectrum analyzer and microwave signal source.



6.2.4.2.2 Test steps



Test steps are as follows:



a) the same as 6.2.4.1.2 a);



b) the same as 6.2.4.1.2 b);



c) the same as 6.2.4.1.2 c);



d) set RBW of spectrum analyzer in each test frequency band respectively and measure the spurious emission power Pcon in each frequency band, as required by Clauses 6 and 7, GB/T 20851.1-2019;



e) under the same test conditions, replace the equipment under test with a microwave signal source and a test antenna with known gain GT, measure the power with spectrum analyzer, and adjust the output power P0 of each frequency band of the microwave signal source until the power measured with spectrum analyzer is equal to Pcon;



f) calculate the spurious equivalent isotropically radiated power e.i.r.pcon of each frequency band using Equation (7):



e.i.r.pcon=P0×GT (7)



g) repeat the above steps to test the spurious emission of each frequency band at other carrier frequencies.



6.2.5 Modulation mode and modulation factor



6.2.5.1 Test equipment



Vector signal analyzer is used as the equipment for modulation mode and modulation factor tests.



6.2.5.2 Test steps



This test may be completed under conduction or radiation test conditions. Test steps are as follows:



a) set the working frequency of the transmitter of the equipment under test and set the equipment under test in the state of continuously transmitting test signals;



b) set the transmitting power of the equipment under test to the maximum;



c) set the modulation factor of the equipment under test to the minimum within its allowable range;



d) use the vector signal analyzer to measure the modulation factor of the equipment under test;



e) change the working frequency of the transmitter of the equipment under test, while keeping the rest of settings unchanged, and test the modulation factor at other carrier frequencies;



f) set the modulation factor of the equipment under test to the maximum within its allowable range;



g) use the vector signal analyzer to measure the modulation factor of the equipment under test;



h) change the working frequency of the transmitter of the equipment under test, while keeping the rest of settings unchanged, and test the modulation factor at other carrier frequencies;



6.2.6 Bit rate



6.2.6.1 Test equipment



Digital oscilloscope is used as the equipment for bit rate test.

Foreword i
1 Scope
2 Normative references
3 Symbols and abbreviations
4 Recommended characteristics of main test equipment and accessories
5 Test conditions
6 Test methods

电子收费 专用短程通信
第5部分：物理层主要参数测试方法
1 范围
GB/T 20851的本部分规定了电子收费专用短程通信物理层主要参数的主要测试设备和附件推荐特性、测试条件和测试方法。
本部分适用于公路和城市道路电子收费系统，自动车辆识别、车辆出入管理等领域可参照使用。
2规范性引用文件
下列文件对于本文件的应用是必不可少的。凡是注日期的引用文件，仅注日期的版本适用于本文件。凡是不注日期的引用文件，其最新版本(包括所有的修改单)适用于本文件。
GB/T 9254信息技术设备的无线电骚扰限值和测量方法
GB/T 12190--2006 电磁屏蔽室屏蔽效能的测量方法
GB/T 20851.1—2019 电子收费 专用短程通信 第1部分：物理层
3符号和缩略语
3.1 符号
下列符号适用于本文件。
D：天线最大直径。
d：被测设备与测试天线间距。
dBc：表征功率与载波信号功率的比值。
dBm；表征功率与1 mW的比值。
e.i.r.pcon：杂散等效全向辐射功率。
e.i.r.pmax：最大等效全向辐射功率。
f1：接收带宽下限频率。
f2：接收带宽上限频率。
fc：信号源发射信号中心频率。
fTx：标称载波频率。
fTxa：实际载波频率。
GRx：被测设备接收天线增益。
GT：测试天线增益。
GTx：被测设备发射天线增益。
h：被测设备与测试天线距地面高度。
PA：邻信道干扰测试信号功率。
PB：阻塞干扰测试信号功率。
PC：同信道干扰测试信号功率。
Pcon：杂散发射功率。
Pcw：被测设备单频信号功率。
Pcwo：信号源及测试天线单频信号功率。
Pi,max：最高输入信号功率。
P0：信号源输出功率。
PR：测量代替被测设备的测试天线接收信号的功率。
RA：邻信道干扰抑制比。
RB：阻塞干扰抑制比。
RC：同信道干扰抑制比。
SRx：接收灵敏度。
SW：唤醒灵敏度。
T0：测试唤醒信号发送起始时间。
TR：发送响应信号起始时间。
TW：唤醒时间。
Δf：频率容限。
λ：波长。
3.2 缩略语
下列缩略语适用于本文件。
OBU：车载单元(On Board Unit)
RBW：分辨率带宽(Resolution Bandwidth)
RSU：路侧单元(Roadside Unit)
VSWR：电压驻波比(Voltage Standing-Wave Ratio)
4主要测试设备和附件推荐特性
4.1 功率计
功率计推荐特性应符合以下要求：
a)功率测量范围：-60 dBm～+20 dBm；
b)频率范围：10 MHz～18 GHz；
c)功率测量误差：±3％。
4.2 频率计
频率计推荐特性应符合以下要求：
a)频率范围：10 Hz～20 GHz；
b)频率测量误差：±10×10-9。
4.3微波信号源
微波信号源推荐特性应符合以下要求；
a)频率范围：250 kHz～20 GHz；
b)频率精度：fc×100×10-9；
c)相噪：小于-98 dBc/Hz@10 GHz，1 kHz偏置。
4.4频谱分析仪
频谱分析仪推荐特性应符合以下要求：
a)频率范围：3 Hz～26.5 GHz；
b)动态范围：不小于70 dB；
c)分辨率带宽：10 Hz～3 MHz；
d)背景噪声：不大于-140 dBm/Hz。
4.5矢量信号分析仪
矢量信号分析仪推荐特性应符合以下要求：
a)频率范围：直流～6 GHz；
b)矢量调制分析类型：幅度调制、频率调制和相位调制分析。
4.6数字示波器
数字示波器推荐特性应符合以下要求：
a)带宽：1 GHz；
b)采样率：2 Gsa/s；
c)存储器深度：每通道2 M点；
d)触发方式：边沿、码型、时间/事件延迟和脉冲宽度等。
4.7测试天线
测试天线推荐特性应符合以下要求：
a)频率范围：30 MHz～20 GHz；
b)极化方式：线极化；
c)VSWR：小于1.5：1；
d)阻抗：50 Ω；
e)增益：可获取。
5测试条件
5.1测试场地及配置
5.1.1 测试场地
辐射测试可在电波暗室或者开阔场中进行。
电波暗室的最小尺寸应满足3 m法测试的要求，屏蔽效能应符合GB/T 12190—2006的要求，归一化场地衰减应符合GB/T 9254的要求。
在电波暗室中进行测试时，被测设备应处在暗室静区范围内。
开阔场的归一化场地衰减应符合GB/T 9254的要求。
5.1.2配置
5.1.2.1 传导测试系统配置
传导测试系统由被测设备、测试设备和连接附件组成，连接附件包括连接器、衰减器等。连接附件根据被测设备接口、被测信号强度确定。传导测试系统配置框图见图1。

被测设备
连接器
同轴电缆
衰减器
测试设备
图1 传导测试系统配置框图
5.1.2.2辐射测试系统配置
辐射测试系统由被测设备、测试设备和连接附件组成，连接附件包括同轴电缆、测试天线、连接器、衰减器等。连接附件根据被测设备接口、被测信号强度确定。辐射测试系统配置框图见图2。

远场区或自由空间
被测设备
增益
最大增益方向
测试
天线
增益GT
同轴电缆
衰减器
测试
设备
图2辐射测试系统配置框图
被测设备与测试天线间距d应满足式(1)：
(1)
被测设备与测试天线距地面高度h应满足式(2)：
h≥4D (2)
5.2测试信号
测试系统应提供以下测试信号：
a)位速率测试信号，调制在工作频点的FM0编码的全零码；
b)同信道、邻信道干扰抑制比干扰测试信号，已调制的未编码的周期为511比特的伪随机二进制序列(PN9)信号；
c)阻塞干扰抑制比干扰测试信号，工作频段(5 725 MHz～5 850 MHz)带外(30 MHz～20 GHz)某固定频点连续波信号；
d)OBU唤醒响应信号，发射在相应信道的载波信号，持续时间20 ms。
5.3被测设备测试状态要求
5.3.1 RSU
被测RSU应能够按照5.2的要求和测试需要接收、发射测试信号。即能够连续发射载波、调制在工作频点的PN9码和FM0编码的全零码，能够引出解调后的接收数据及时钟信号，并提供测试点。
5.3.2 OBU
被测OBU应能够按照5.2的要求和测试需要接收、发射测试信号。即能够发射载波、调制在工作频点的PN9码和FM0编码的全零码，被唤醒后发送唤醒响应信号。能够引出解调后的接收数据及时钟信号，并提供测试点。
5.3.3 OBU初始化设备
被测OBU初始化设备应能够按照5.2的要求和测试需要接收、发射测试信号。即能够发射载波、调制在工作频点的PN9码和FM0编码的全零码.能够引出解调后的接收数据及时钟信号，并提供测试点。
6 测试方法
6.1 总则
测试过程中具备采用传导测试能力的项目，宜采用传导测试方法进行测试。
6.2 RSU测试
6.2.1载波频率、频率容限
6.2.1.1测试设备
载波频率、频率容限测试设备为频率计或带有计数器的频谱分析仪。
6.2.1.2测试步骤
本测试可在传导或辐射测试条件下完成，测试步骤如下：
a)设置被测设备发射机工作频率，设置被测设备工作在非调制状态，即载波状态；
b)用频率计或带有计数器的频谱仪测量被测设备的实际载波频率fTxa；
c)按式(3)计算该载波频率的频率容限Δf：
(3)
d)重复以上步骤，测试其他的载波频率及其频率容限。
6.2.2 占用带宽
6.2.2.1 测试设备
占用带宽测试设备为频谱分析仪。
6.2.2.2测试步骤
本测试可在传导或辐射测试条件下完成，测试步骤如下：
a)设置被测设备发射机工作频率，设置被测设备为连续发射测试信号的状态；
b)将被测设备的发射功率设置为最大值；
c)用频谱分析仪测量该测试信号的占用带宽；
d)重复以上步骤，测量其他载波频率下的占用带宽。
6.2.3等效全向辐射功率
6.2.3.1 传导测试
6.2.3.1.1 测试设备
等效全向辐射功率传导测试设备为功率计。
6.2.3.1.2测试步骤
测试步骤如下：
a)设置被测设备发射机工作频率，设置被测设备为非调制状态，即载波状态；
b)将被测设备的发射功率设置为最大值；
c)用功率计测量被测设备发射天线端口功率Pcw，按式(4)计算最大等效全向辐射功率e.i.r.pmax：
e.i.r.Pmax=Pcw×GTx (4)
d)重复以上步骤，测试其他载波频率下的等效全向辐射功率。
6.2.3.2辐射测试
6.2.3.2.1测试设备
等效全向辐射功率辐射测试设备包括功率计、微波信号源。
6.2.3.2.2测试步骤
测试步骤如下：
a)按6.2.3.1.2 a)进行；
b)接6.2.3.1.2 b)进行；
c)用功率计测量功率Pcw；
d)在同样的测试条件下，用微波信号源和已知增益GT的测试天线代替被测设备，并用功率计测量功率Pcwo，调整微波信号源的输出功率P0，直至Pcwo等于Pcw；
e)按式(5)计算最大等效全向辐射功率e.i.r.pmax：
e.i.r.pmax=P0×GT (5)
f)按6.2.3.1.2 d)进行。
6.2.4杂散发射
6.2.4.1传导测试
6.2.4.1.1测试设备
杂散发射传导测试设备为频谱分析仪。
6.2.4.1.2测试步骤
测试步骤如下：
a)设置被测设备发射机工作频率，设置被测设备为连续发射测试信号的状态；
b)将被测设备的发射功率设置为最大值；
c)将被测设备的调制系数设置为其允许范围内的最大值；
d)按CB/T 20851.1—2019中第6章、第7章的要求分别设置频谱分析仪在各测试频段的RBW，测量该频段的杂散发射功率Pcon；
e)按照式(6)计算该频段的杂散等效全向辐射功率e.i.r.pcon：
e.i.r.pcon=Pcon×GTx (6)
f)重复以上步骤测量其他载波频率下的杂散发射。
6.2.4.2辐射测试
6.2.4.2.1 测试设备
杂散发射辐射测试设备包括频谱分析仪、微波信号源。
6.2.4.2.2测试步骤
测试步骤如下：
a)按6.2.4.1.2 a)进行；
b)按6.2.4.1.2 b)进行；
c)按6.2.4.1.2 c)进行；
d)按GB/T 20851.1—2019中第6章、第7章的要求分别设置频谱分析仪在各测试频段的RBW，测量各频段的杂散发射功率Pcon；
e)在同样的测试条件下，用微波信号源和已知增益GT的测试天线代替被测设备，并用频谱分析仪测量功率，调整微波信号源各频段的输出功率Po，直至频谱分析仪测得的功率等于Pcon；
f)按式(7)计算相应各频段的杂散等效全向辐射功率e.i.r.pcon：
e.i.r.pcon=Po×GT (7)
g)重复以上步骤测试其他载波频率下各频段的杂散发射。
6.2.5调制方式、调制系数
6.2.5.1 测试设备
调制方式、调制系数测试设备为矢量信号分析仪。
6.2.5.2 测试步骤
本测试可在传导或辐射测试条件下完成。测试步骤如下：
a)设置被测设备发射机工作频率，设置被测设备为连续发射测试信号的状态；
b)将被测设备的发射功率设置为最大值；
c)将被测设备的调制系数设置为其允许范围内的最小值；
d)用矢量信号分析仪测量被测设备的调制系数；
e)改变被测设备发射机工作频率，其余设置不变，测试其他载波频率下的调制系数；
f)将被测设备的调制系数设置为其允许范围内的最大值；
g)用矢量信号分析仪测量被测设备的调制系数；
h)改变被测设备发射机工作频率，其余设置不变，测试其他载波频率下的调制系数。
6.2.6位速率
6.2.6.1 测试设备
位速率测试设备为数字示波器。
6.2.6.2测试步骤
本测试可在传导或辐射测试条件下完成。测试步骤如下：
a)设置被测设备发射机工作频率，设置被测设备为连续发射测试信号的状态；
b)将被测设备的发射功率设置为最大值；
c)将被测设备的调制系数设置为其允许范围内的最大值；
d)用数字示波器测量位速率；
e)重复以上步骤测量其他载波频率下的位速率。
6.2.7接收灵敏度
6.2.7.1 传导测试
6.2.7.1.1 测试设备
接收灵敏度传导测试设备包括矢量信号源、误码仪。
6.2.7.1.2测试步骤
测试步骤如下：
a)设置被测设备接收机工作频率，设置被测设备为正常工作状态；
b)用矢量信号源通过测试电缆发送被测设备工作信道中心频率的测试信号至被测设备接收机输入端以及误码仪；
c)将被测设备接收机输出的解调后的数据信号和时钟信号接入误码仪，测量被测接收机的误码率；
d)调整矢量信号源发送测试信号的功率P0，直至被测接收机的误码率达到标准要求的限值；
e)按式(8)计算被测设备在该工作信道的接收灵敏度SRx：
(8)
f)重复以上步骤，测试其他工作信道的接收灵敏度。
6.2.7.2辐射测试
6.2.7.2.1测试设备
接收灵敏度辐射测试设备包括矢量信号源、误码仪、频谱分析仪。
6.2.7.2.2测试步骤
测试步骤如下：
a)按6.2.7.1.2 a)进行；
b)用矢量信号源通过测试天线发送被测设备工作信道中心频率的测试信号至被测设备接收机输入端以及误码仪；
c)按6.2.7.1.2 c)进行；
d)按6.2.7.1.2 d)进行；
e)在同样的测试条件下，用已知增益GT的测试天线代替被测设备，并用频谱分析仪测量测试天线接收信号的功率PR；
f)按式(9)计算被测设备在该工作信道的接收灵敏度SRx：
(9)
g)按6.2.7.1.2 f)进行。
6.2.8 接收带宽
6.2.8.1传导测试
6.2.8.1.1 测试设备
接收带宽传导测试设备包括矢量信号源、误码仪。
6.2.8.1.2测试步骤
测试步骤如下：
a)设置被测设备接收机工作频率，设置被测设备为正常工作状态；
b)用矢量信号源通过测试电缆发送被测设备工作信道中心频率的测试信号至被测设备接收机输入端以及误码仪；
c)将被测设备接收机解调后的数据信号和时钟信号接入误码仪，测量被测设备接收机的接收灵敏度；
d)设置测试信号功率P0比被测设备接收机接收灵敏度高6 dB；
e)降低矢量信号源发送信号频率，直至被测接收机的误码率达到但不超过标准要求的限值；记录该接收带宽下限频率为f1升高矢量信号源发送信号频率，直至被测接收机的误码率达到但不超过标准要求的限值；记录该接收带宽上限频率为f2；
f)被测设备接收带宽为f1～f2；
g)重复以上步骤，测试其他工作信道的接收带宽。
6.2.8.2辐射测试
6.2.8.2.1 测试设备
接收带宽辐射测试设备包括矢量信号源、误码仪。
6.2.8.2.2测试步骤
测试步骤如下：
a)按6.2.8.1.2 a)进行；
b)用矢量信号源通过测试天线发送被测设备工作信道中心频率的测试信号至被测设备接收机输入端以及误码仪；
c)按6.2.8.1.2 c)进行；
d)按6.2.8.1.2 d)进行；
e)按6.2.8.1.2 e)进行；
f)按6.2.8.1.2 f)进行；
g)按6.2.8.1.2 g)进行。
6.2.9最高输入信号功率
6.2.9.1传导测试
6.2.9.1.1 测试设备
最高输入信号功率传导测试设备包括矢量信号源、误码仪。
6.2.9.1.2测试步骤
测试步骤如下：
a)设置被测设备接收机工作频率，设置被测设备为正常工作状态；
b)用矢量信号源通过测试电缆发送被测设备工作信道中心频率的测试信号至被测设备接收机输入端以及误码仪；
c)将被测设备接收机解调后的数据信号和时钟信号接入误码仪，测量被测设备接收机的误码率；
d)调整增大矢量信号源发送测试信号的功率P0，直至被测接收机的误码率达到但不超过标准要求的限值；
e)按式(10)计算被测设备在该工作信道的接收误码率达到标准要求时所允许的最高输入信号功率Pi,max：
(10)
f)重复以上步骤，测试其他工作信道的最高输入信号功率。
6.2.9.2 辐射测试
6.2.9.2.1测试设备
最高输入信号功率辐射测试设备包括矢量信号源、误码仪、频谱分析仪。
6.2.9.2.2 测试步骤
测试步骤如下：
a)按6.2.9.1.2 a)进行；
b)用矢量信号源通过测试天线发送被测设备工作信道中心频率的测试信号，至被测设备接收机以及误码仪；
c)按6.2.9.1.2 c)进行；