GB/T 6934-1995 短波单边带接收机电性能测量方法

UDC621-396-62:621-317.3

M74疡8

中华人民共和国国家标准

GB/T6934一1995

短波单边带接收机电性能测量方法

Methodsofmeasurementofelectricalperformance

forshortwavesingle-sidebandreceivers

1995一04一06发布1995一11一01实施

国家技术nk督局发布

目次

主题内容与适用范围·································”·················“，·························…·…(1

引用标准············································”····“·····························”·············……(1

术语················································……”············”····“·······“···········”·····一(工

乙音频试验负载······························”·”··························”····””····“·············……(

凡基准输出电平······································”···········“························……(1)

3.3信纳德········································································”·········……(1)

3.4标准信纳德···························”··“······“·······································“··········……(1)

3.5信噪比·······················································..·”····”·······················”···……(1)

3.6标准信噪比·············································“························”·”····“··········……(2)

4标准试验条件············”··············“················”···”·“··························“···……(2)

4.1标准大气条件·······················································”·”·”·”····“··············”……(2)

4.2标准电源条件·······················.·，························································”···……(3)

5补充试验条件···”····································”····”·“······“·············”····“·“······……(3)

5.1输人信号源···························”··························”······················一·(3)

5.2测量设备的连接·······································”·”····“························”·······……(4)

5.3音频频带的限制····”··································”····”·“···“················”·”····“·……(4)

5.4测量设备的特性····································”·“·····“························”·”·········……(4)

5.5测量工作场所条件·······································”·····················”···……(5)

6电性能定义和测量方法········································””·····“·················……”·“·…(5)

6.1频率误差”···································”··““·“·················””·”·”····“·····……(5)

62频率稳定度······································“····“·····················”··””·“·”·········……:(5)

6.3基准灵敏度·······················································”·”··”···“·“·“··……(6)

6.4大信号信噪比····································“····························”····”·”············……(6)

6.5音频响应”(7)

6.6边带线性窜扰·”·······················”·····················”································……(7)

6.;群时延(包络时延失真)························…·…“···..········……”·…·…”“·..····……”·(7)

6.8中频选择性·”·”····”··························””··”····“··················”····”····“·········一(8)

6.9总失真系数························””··················································”·“·······……(8)

6.扣相对音频互调(带内互调卜···”·”·“·“···········”··“·········……”·…”····.……(9)

6.11边带非线性窜扰·························””····················”····“···“················”···……(9)

6.:2带外互调·······································”·”··············””·“···“···················”·……(10)

6.13邻近信号选择性··”··········、··“··················”····“·········”·”····”·“·“··…(11)

6.14阻塞”·”························”·”····”·”·“·“··””········”·”··”·····.·，···”·”·”·…(11)

6.15倒易混频······”·“·········“···········”······”·········”·”··········”·”····“······……(11)

6.16中频抑制比”·····················”····”·”····”·”·“·”·”·“·········”·”·”····“·“·······”··“”·(12)

6.:7镜频抑制比······················””·”····“”·“·“一，·················””·”·“···“······”·”一(12)

6.18杂散频率抑制比·····························································。··········……二‘二‘’二二‘(12)

6.19组合音···········································.·，·················································……(13)

6.2。自动增益控制特性··················································································……(13)

6.21射频增益控制····································································。·················……(13)

6.22音鱼控制或线路电平调整···························。。·························，············……’二’二(13)

6.23传导杂散分量(14)

6.24相位抖动······························································································……(14)

附录A混合网络的示例(补充件)·····················································.，··········。……(16)

附录B测量仪器品种和射频信号发生器的特性(辛卜充件)(17)

附录C互调输入截点值的测量(补充件)(18)

附录n人工电源网络(补充件).·····································································…·…(19)

附录E最大频率误差的测量(参考件)(20)

中华人民共和国国家标准

短波单边带接收机电性能测量方法GB/T6934一1995

Methodsofmeasurementofelectricalperformance代替GB6934--86

forshortwavesingle-sidebandreceivers

主题内容与适用范围

本标准规定了短波单边带接收机(简称接收机)的电性能测量条件、定义和测量方法。

本标准适用于不带有完整天线的接收设备，其音频带宽不超过10kH:的全载波(H3E)、减幅载波

(R3E)和抑制载波(]3E)、包括独立边带(138E)的短波单边带接收机。也适用于可以兼容接收双边带调

幅话(A3E)、等幅报(AIA,AlB)的短波单边带接收机。

本标准仅提供电气性能的测量方法及其有关条件的规定，测量项目以及性能指标按设备规范的规

定。

对于特殊接收机，本标准没有规定的电气性能项目的定义和测量方法，由供需双方协商自行规定.

引用标准

GB2421电工电子产品基本环境试验规程总则

术语

-'.1音频试验负载audio-frequencytestload

音频试验负载是代替接收机正常工作时所连接的负载的阻抗网络，它模拟正常负载和正常使用电

缆的阻抗。网络由制造厂规定，通常用单一纯电阻组成。

3.2基准输出电平referenceoutputlevel

接收机在规定的工作条件下，连接规定的音频试验负载时的春刃输出功率，它用来做测量的基准电

平。

3.3信纳德SINAD

音频试验负载上的有用信号加噪声加失真的输出功率和与噪声加失真的功率和之比:

S+N+D

(1)

N+D

式书:S—标准试验调制产生的有用音频信号;

N—标准试验调制的噪声;

D—标准试验调制的失真。

3.4标准信纳德standardSINAD

本标准规定，标准信纳德为12dB,

三5信噪比signal-to-noiseration

Y家技术监督局1995一04一06批准1995一11一01实施

GB/T6934一1995

音频试验负载上的有用信号加噪声的输出功率与噪声功率之比:

s+N

(2)

N

式中:s—标准试验调制产生的有用音频信号;

A'-噪声

16标准信噪比，tandardsignal-to-noiseration

本标准规定，标准信噪比为12dB.

标准试验条件

除非另有规定，测量均应在标准试验条件下进行。

4.1标准大气条件

标准大气条件符合GB2421的规定。

4.1.，基准标准大气条件

如果被测参数随温度和(或)气压而变化的规律是已知的，则应在本标准4.1.3条中规定的试验标

准大气条件下测量参数值。必要时，可以通过计算校正到下列基准的标准大气条件下的参数值。

温度:20C;

气压:101.3kPaa

注:由于相对湿度不能通过计算来校正，因此不予规定

4.1.2仲裁试验的标准大气条件

如被测参数随温度、气压和湿度变化的规律未知时，则通过协议，选择表1所列仲裁试验的标准大

气条件之一进行测量。

当测量的温度不是20C或不是有关标准中规定的上述其他值时，可由供需双方协议，规定特定参

数的合适极限值。

注:如果相对湿度对试验结果没有影响，则可不予考虑

表1

温度相对湿度

C%气压

kPa

标称值窄容差宽容差窄范围宽范围

20士1士263-6760--7086-106

23士1士248-52455586-106

25士1士248^-5245-5586-106

27士1士263^6760-7086-106

，

3试验的标准大气条件

测量和试验的标准大气条件范围见表2,

表2

温度相对湿度气压

15^35'C45%一7586^-106kPa

ce/T6934一1995

当不能在标准大气下进行测量时，实际条件要在试验报告上写明。

在对所给定的设备进行的一系列测量中，作为整个试验的一部分，温度和相对湿度应大体稳定。

4.2标准电源条件

电源的电压及其频率在接收机工作时的电源输人端测量。如果接收机接有不可拆卸的电线、电缆

时，可以在电源输入插头上测量，但要记录电线、电缆的类型、截面形状和长度等。

标准电源条件分直流电源和交流电源两种。

4.2.，直流电源的标准试验电压

总直流电源标准试验电压按总标称电压计，其误差应为士2%，脉动应小于2%.

4.2.2交流电源的标准试验电压及其频率

无特殊规定时，标准试验电压为220v，其误差应为士2%，标准试验频率为50Hz，其误差应为士

2%，谐波失真系数应小于5%,

5斗卜充试验条件

5.1输入信号源

5.1，1具有适当天线接头的接收机测量用的输入信号源的配置

输入信号源应由射频信号发生器、传输线和阻抗匹配网络组成(见图1).

l

f一一-一一一k尸，2

I尸，一，:n_

'TIE.

匕______JL--____J

图1输入信号源的配ti

1一内阻为R。的射频信号发生器沼一传描线;3--阻抗匹配网络(缓冲器，选择使用);

4-接收机标称输入阻抗R:R.-输入信号源内阻

匹配网络电阻值应按公式(3),(4),(5)选择:

2寸NR;R二

R2(3)

N一1

n。{N+11。

八1二八ii二军一丁!一八，·”“…”..….…“··…。..·…(4)

气w一1/

N十1

R，二R一Rz(5)

N一1

式巾:N—要求的功率衰减比。

标称