标准编号:	GJB 2361-1995
中文名称:	星地测控回路试验方法
英文名称:	Methods for matching test of satellite and TT&C station
行业分类:	GJB    国家军用行业标准
发布机构:	国防科学技术工业委员会
发布日期:	1995-05-31
实施日期:	1995-12-1
标准状态:	valid
翻译语言:	英文
文件格式:	PDF
翻译字数:	12000 字
交付时间:	1 个工作日

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. Methods for matching test of satellite and TT&C station 1 Scope 1.1 Subject content This standard specifies the matching test contents and methods of satellite TT&C system and ground TT&C station (airship). 1.2 Application scope This standard is applicable to the matching test of satellite and TT&C system before satellite flight test. Each model may be tailored according to the actual situation. 2 Normative references There is no provision in this clause. 3 Definitions 3.1 static matching test of satellite and TT&C station joint test on system performance and working programs of satellite TT&C system and related equipment and TT&C system of TT&C station (airship) 3.2 dynamic matching test of satellite and TT&C station joint test on system performance and working programs of satellite TT&C system and related equipment on revised flight and ground TT&C station 3.3 satellite TT&C simulator equipment simulating satellite TT&C function in matching test of satellite and TT&C station 3.4 satellite attitude & orbital motion simulator equipment that receives attitude and orbit data and converts the attitude and orbit control parameters into remote control command information and control data according to dynamics and kinematics laws 3.5 satellite simulator generic terms of satellite TT&C simulator and satellite attitude & orbital motion simulator   4 General requirements 4.1 Test purpose a. Verify the coordination of joint work of satellite and TT&C system and related equipment; b. Verify the technical state and main TT&C technical performance of satellite and TT&C equipment; c. Rehearse the working program of satellite and TT&C system; d. Simulate satellite failures and rehearse emergency treatment methods; e. Commanders and operators performing tasks perform field drills according to working programs. 4.2 Test conditions a. The newly developed satellite system shall be subjected to matching test of satellite and TT&C station; b. Before each satellite is launched, the matching test of satellite and TT&C station shall be arranged as needed; c. Due to the needs of satellite TT&C system, when the TT&C equipment has been greatly modified, the matching test of satellite and TT&C station shall be arranged. 4.3 Test site and equipment 4.3.1 Test site The matching test is generally carried out at satellite TT&C station (airship). Personnel activities and object movements are prohibited near the antenna in test site. 4.3.2 Test equipment Satellite-borne equipment or simulation equipment and TT&C station (airship) equipment with the same electrical performance as satellite-borne equipment is adopted for matching joint test. 4.4 Test environmental conditions 4.4.1 The test environmental conditions for TT&C station (airship) equipment shall be specified according to the special technical specifications for equipment. 4.4.2 Atmospheric conditions for satellite-borne equipment, simulation equipment and test and detection equipment: a. temperature: 0~45℃; b. relative humidity: ≤80%; c. air pressure: local air pressure. 5 Detailed requirements 5.1 Static matching test of monopulse radar Place the director radar beacon, radar transponder and their antennas on the radar calibration tower, and set the uplink and downlink levels of RF signals according to the test contents. 5.1.1 Ranging accuracy test of radar Switch on director radar beacon and radar transponder. The director radar tracks the director beacon antenna, and test the performance of director radar and the stability of signals received by beacon. The director monopulse radar points to the transponder antenna. The radar sends pulse signals to trigger the radar transponder, and the monopulse radar antenna tracks the transponder antenna. At the same time, measure the fixed delay and delay stability of the transponder so as to obtain the ranging accuracy and calculate the statistical angle measurement accuracy. 5.1.2 Frequency measurement accuracy test of radar When the radar triggers the transponder, measure the RF frequency and frequency stability of the answer signal so as to obtain the frequency measurement accuracy. 5.1.3 Switch-on capture characteristic test of radar transponder Measure the time from switch-on to normal signal response of radar transponder, and measure the value of frequency and pulse delay varying with time at different time after switch-on. 5.1.4 Working frequency band test of radar transponder Change the transmitting frequency of radar, and measure the frequency band of transponder transmitting radar signal. 5.2 Static matching test of dual-frequency velocimeter Place the satellite-borne dual-frequency transmitter and antenna in the test room or calibration tower at TT&C station, and measure the frequency stability of dual-frequency transmitter through the equipment of TT&C station. Preheat the satellite-borne transmitter, and test the frequency stability after the frequency is stable. The data of continuous measurement for 20min is regarded as a group, and the data are generally processed by Allan variance. During the measurement of multiple groups of data, the time for continuous measurement of each group of data may be shortened appropriately. The high-end and low-end frequency stability, comprehensive frequency stability and dual-frequency frequency accuracy shall be measured. 5.3 Static matching test of ultrashort wave remote control Place the satellite-borne remote control equipment and antenna on the test room or calibration tower at TT&C station. Generally, the transmitting power of remote transmitter at TT&C station is limited to less than 10mW, and the modulation index is 2.5, 3.0 and 3.5 respectively. 5.3.1 In the test command channel, the remote control command is sent by hand, and the satellite-borne test equipment monitors and records the receiving result of command. 5.3.2 The computer controls the sending of remote control commands, and the satellite-borne test equipment monitors and records the receiving result of command. The computer controls the remote control command chain, and the satellite-borne test equipment monitors and records the receiving result of command. 5.4 Static matching test of ultrashort wave telemetry Place the satellite-borne telemetry equipment on the test room or calibration tower at TT&C station. Switch on the satellite-borne telemetry equipment and the TT&C station receives the data. 5.4.1 Verify the correctness of telemetry frequency, demodulation, bit error rate and data format. 5.4.2 The TT&C station processes the received telemetry data. 5.5 Static matching test of ultrashort wave ranging Place the satellite-borne ranging receiver, dual-frequency transmitter and antenna on the calibration tower at TT&C station for test, or use the simulator of satellite-borne equipment to replace satellite-borne ranging equipment for test. 5.5.1 Test with satellite-borne ranging equipment Use phase modulation/phase modulation mode for the uplink and downlink of ranging system, and carry out the test after the satellite and TT&C station equipment is stabilized after switch-on. 5.5.1.1 Measurement of distance zero value and phase matching value of each sidetone Adjust the levels of uplink and downlink signals to the receiving sensitivity level through attenuator, the modulation degree is the rated value, the carrier frequency is the used center frequency, and measure the distance zero value and the phase matching value of each sidetone in two states of "measurement" and "self-calibration” by distance measuring equipment at TT&C station. Measure ten groups of data for statistical processing so as to obtain the distance zero value and phase matching value of satellite-borne system. 5.5.1.2 Ranging accuracy of measurement system Adjust the levels of uplink and downlink signals to the receiving sensitivity level through attenuator, the modulation degree is the rated value, the carrier frequency is the used center frequency, and the distance measuring equipment of TT&C station measures the distance zero value in two states of "measurement" and "self-calibration” and carry out statistical processing for multiple groups of measured data so as to calculate the ranging accuracy value of ranging system. 5.5.1.3 Measurement of retransmitting sidetone modulation degree and frequency spectrum When the telemetry signal is modulated by the satellite-borne transmitter, measure the sidetone spectrum of the retransmitted signal by a spectrum analyzer, so as to obtain the modulation degree, sidetone spectrum structure and clutter spectrum. 5.5.1.4 Measurement of influence of various factors on ranging accuracy According to the requirements of satellite orbit measurement, change the uplink and downlink levels, carrier frequency (Doppler frequency offset) and modulation degree by 10%, and measure the change value of distance zero value caused by various changes through distance measuring equipment, so as to obtain the influence on ranging accuracy. 5.5.1.5 Measurement of stability of distance zero value Take a group of distance zero value data every 10min by the distance measuring equipment at TT&C station, with 10 groups taken in total, and the change of distance zero value shall not be out of the use range. 5.5.2 Test with simulator Test contents are the same as those in 5.5.1. Compare the measurement result with that of satellite-borne equipment, which may be used as a reference for the equipment detection of TT&C station. 5.5.3 Error propagation test of ultrashort wave ranging distance zero value Before satellite launch, the test shall be carried out at the final assembly plant, special test site or TT&C station. Use phase modulation/phase modulation mode for the uplink and downlink of test system. Carry out the test after the satellite and TT&C station equipment is stabilized after switch-on. Adjust the levels of uplink and downlink signals to the receiving sensitivity level through attenuator, the modulation degree is the rated value, and the carrier frequency is the used center frequency. 5.5.3.1 Measure the distance zero value of satellite ranging system and the phase value of each sidetone by distance measuring equipment for satellite comprehensive test. 5.5.3.2 Measure the distance zero value of simulator and the phase value of each sidetone bydistance measuring equipment for satellite comprehensive test . 5.5.3.3 Compare the distance zero value between the satellite-borne ranging system and the simulator and the difference of phase value of each sidetone, which serves as the calibration basis for the equipment of TT&C station to measure the distance zero value. 5.5.3.4 Measure the distance zero value of simulator and the phase value of each sidetone by distance measuring equipment at each ground TT&C station, compare and analyze the measured zero value and phase value with those measured by distance measuring equipment for satellite comprehensive test, complete the error propagation, and obtain the ranging value that shall be deducted when performing the flight mission.

1 Scope 2 Normative references 3 Definitions 4 General requirements 5 Detailed requirements Additional explanation

1 范围 1.1 主题内容 本标准规定了卫星测控系统与地面测控站(船)的回路试验内容和方法。 1.2 适用范围 本标准适用于卫星飞行试验前的星地测控系统回路试验。各型号可以根据本型号实际情况适当剪裁。 2 引用文件 本章无条文。 3 定义 3.1 星地静态对接试验 static matching test of satellite and TT&C station 星上测控系统及有关设备与测控站(船)的测控系统进行系统性能和工作程序的联试。 3.2 星地校飞 dynamic matching test of satellite and TT&C station 星上测控系统及有关设备在校飞飞机上与地面测控站进行系统性能和工作程序的联试。 3.3 卫星测控模拟器 satellite TT&C simulator 星地回路试验中模拟卫星测控功能的设备。 3.4 卫星姿态与轨道运动仿真器 satellite attitude & orbital motion simulator 接收姿态和轨道数据，根据动力学和运动学规律将姿态与轨道控制参数转换成遥控指令信息和控制数据的设备。 3.5 卫星模拟器 satellite simulator 卫星测控模拟器和卫星姿态与轨道运动仿真器的总称。 4 一般要求 4.1 试验目的 a. 验证星地测控系统及有关设备联合工作的协调性； b. 验证星地设备的技术状态和主要测控技术性能； c. 演练星地测控系统的工作程序； d. 模拟卫星故障，演练应急处理方法； e. 执行任务的指挥员、操作员根据工作程序进行实地演练。 4.2 试验时机 a. 对新研制的卫星系统应安排进行星地测控回路试验； b. 每颗卫星发射前，根据需要安排星地测控回路试验； c. 由于卫星测控系统本身的需要，测控设备作了重大修改时，应安排星地测控回路试验。 4.3 试验场地和设备 4.3.1 试验场地 回路试验一般在卫星测控站(船)进行。试验场地天线附近禁止人员活动和物体移动。 4.3.2 试验设备 利用星上设备或电气性能与装星设备一致的仿真设备和测控站(船)设备进行回路联试。 4.4 试验环境条件 4.4.1 测控站(船)设备的试验环境条件按设备专用技术条件规定。 4.4.2 星上设备、仿真设备和试验检测设备的大气条件： a. 温度：0～45℃； b. 相对湿度：不大于80％； c. 气压：当地大气压。 5 详细要求 5.1 单脉冲雷达静态对接试验 引导雷达信标机和雷达应答机及其天线置于雷达校准塔上，根据试验内容设置射频信号上、下行电平。 5.1.1 雷达测距精度试验 引导雷达信标机和雷达应答机开机。引导雷达跟踪引导信标机天线，测试引导雷达的性能和接收信标机信号的稳定性。引导单脉冲雷达天线指向应答机天线。雷达发送脉冲信号，触发雷达应答机，单脉冲雷达天线跟踪应答机天线，同时测量应答机的固定延时和延时稳定度，得出测距精度，计算统计测角精度。 5.1.2 雷达测频精度试验 雷达触发应答机时，测出回答信号的射频频率及频率稳定度，得出测频精度。 5.1.3 雷达应答机开机捕获特性试验 测量雷达应答机由开机到能够正常应答信号的时间，测量开机后不同时刻频率和脉冲延时随时间变化的数值。 5.1.4 雷达应答机工作频带测试 改变雷达的发射频率，测量应答机转发雷达信号的频带。 5.2 双频测速仪静态对接试验 星载双频发射机和天线置于测控站试验室内或校准塔上，用测控站的设备测量双频发射机的频率稳定度。 星上发射机预热，待频率稳定后开始测试频率稳定度。连续测量20min数据为一组，一般用阿仑方差对数据进行处理。测量多组数据时，可把每组连续测量数据的时间适当缩短。要求测量高端和低端频率稳定度、综合频率稳定度和双频的频率精度。 5.3 超短波遥控静态对接试验 星载遥控设备和天线置于测控站试验室或校准塔上。测控站遥控发射机发射功率一般限制在10mW以下，调制指数分别选2.5，3.0和3.5。 5.3.1 试验指令通道，采用手控发送遥控指令，星上试验设备监视、记录指令接收结果。 5.3.2 计算机控制发送遥控指令，星上试验设备监视、记录指令接收结果。计算机控制发送遥控指令链，星上试验设备监视、记录指令接收结果。 5.4 超短波遥测静态对接试验 星载遥测设备置于测控站试验室或校准塔上。星载遥测设备开机，测控站接收。 5.4.1 验证遥测频率、解调、误码率和数据格式的正确性。 5.4.2 测控站对接收的遥测数据进行处理。 5.5 超短波测距静态对接试验 星载测距接收机、双频发射机和天线置于测控站校准塔上进行试验，或者使用星载设备的仿真器代替星载测距设备进行试验。 5.5.1 使用星载测距设备试验 测距系统上、下行采用调相/调相方式，星地设备开机达到稳定后进行试验。 5.5.1.1 测量距离零值和每个侧音的相位匹配值 利用衰减器使上、下行信号电平调到接收灵敏度电平，调制度为额定值，载波频率为使用的中心频率，测控站测距机分别在“测量”和“自校”两种状态下，测量距离零值和每个侧音的相位匹配值。测量10组数据统计处理，得出星上系统的距离零值和相位匹配值。 5.5.1.2 测量系统的测距精度 利用衰减器使上、下行信号电平调到接收灵敏度电平，调制度为额定值，载波频率为使用的中心频率，测控站测距机分别在“测量”和“自校”两种状态下，测量距离零值，经多组测量数据统计处理，计算出测距系统的测距精度值。 5.5.1.3 测量转发侧音调制度和频谱 在星载发射机调制遥测信号的情况下，利用频谱分析仪测量转发信号的侧音频谱，得出调制度、侧音频谱结构和杂波频谱。 5.5.1.4 测量各因素对测距精度的影响 根据卫星轨道测量要求，改变上、下行电平、载波频率(多卜勒频偏)和改变调制度10％，测距机测量各项变化引入的距离零值的变化值，得出对测距精度的影响。 5.5.1.5 测量距离零值的稳定性 测控站测距机每隔10min取一组测量的距离零值数据，共取10组，距离零值的变化不应超出使用范围。 5.5.2 使用仿真器试验 试验内容同5.5.1条。测量结果和星载设备的测量结果比较，作为测控站设备检测的参考。 5.5.3 超短波测距距离零值的误差传递试验 卫星发射之前，在总装厂、专门试验场地或测控站进行。 试验系统上、下行采用调相/调相方式。星地设备开机达到稳定后进行试验。利用衰减器使上、下行信号电平调到接收灵敏度电平，调制度为额定值，载波频率为使用的中心频率。 5.5.3.1 利用卫星综合测试测距机测量卫星测距系统的距离零值和每个侧音的相位值。 5.5.3.2 利用卫星综合测试测距机测量仿真器距离零值和每个侧音的相位值。 5.5.3.3 比较星载测距系统与仿真器的距离零值和每个侧音相位值差异，作为测控站设备测定距离零值的标定依据。 5.5.3.4 在各地面测控站用测距机测量仿真器的距离零值和各侧音相位值，用所测得的零值和相位值与用卫星综合测试测距机所测的零值相位值比较分析，完成误差传递，得出执行飞行任务时测距应扣除的值。 5.6 超短波统一测控系统静态对接试验 参加对接试验的星上设备，包括遥测、遥控、双频发射机、星载程序控制装置(或星上计算机)和天线，在测控站试验室中连接成试验系统。 5.6.1 遥控、遥测回路试验 测控站设备发送遥控指令链，星载试验设备接收遥控指令，通过遥测和双频发射机通道向下发送遥测信号，测控站接收并处理出遥测参数，检查遥控指令执行结果。试验中星载设备的遥控指令执行情况应有监视手段。 5.6.2 数传上、下行回路试验 测控站发送数传数据，通过遥控通道注入到星上。注入的数据通过双频发射机通道返回测控站，与发送的数据进行比对，数据比对正确，再由遥控发指令，把已注入到星上的数据送到星上程控装置(或控制计算机)中。程控装置(或控制计算机)把收到数据正确的标志，由遥测系统送到测控站检查。 5.6.3 星地时间比对试验 由星上程控装置(或控制计算机)通过遥测把星上的时间码数据传到测控站，由测控站计算机计算出星地时间的差值及变化，确定星地时间误差。 5.6.4 星地飞行程序试验 按照卫星入轨段、运行段和返回段正常工作程序，并进行演练。 5.6.5 故障对策试验 试验正常工作程序之后，设置一些可能出现并影响卫星整个测控系统正常工作的星上设备和地面设备的软硬件故障，运行工作程序，试验故障对策，并进行演练。 5.6.6 仿真器和卫星测控设备一致性标定试验 试验内容和方法与卫星设备做法一致。 5.7 微波统一测控系统静态对接试验 星上测控系统TT&C硬件部分(TT&C装星正样产品或卫星模拟器)可以置于机房内或标校塔上。置于机房内时，测控站发射机通过电缆与TT&C硬件连接起来。置于标校塔上时，测控站发射机通过天线与TT&C硬件沟通信道。 5.7.1 应答机AGC电压标定 5.7.1.1 AGC电压标定 提前将应答机及地面设备加电，标定好连接电缆的衰减量，用标准信号源给应答机输入信号，调整信号源输出功率，使输入到应答机的信号电平在弱信号时按每1dB一个点变化，强信号时按每5dB一个点变化，观察并记录应答机的AGC值。 5.7.1.2 AGC电压特性曲线测量 上行频率对准鉴频零点电压所表示的频率，下行信号电平比额定值高20dB，按额定的调制度，改变上行载频信号强度(弱信号时每1dB时一个点，强信号时每5dB时一个点)，从遥测相应的波道中读出AGC电压值，得出AGC特性曲线。 5.7.2 鉴频特性测试 上行功率电平比额定值高20dB，上行频率为标称频率，从编码遥测相应波道中读出并记录鉴频偏压值，改变上行频率，得出鉴频特性曲线。 5.7.3 应答机灵敏度测量 采用上行调相体制时，测试应答机起始锁定的最小输入电平，即为应答机的灵敏度。 采用上行调频体制时，在额定频偏条件下，测试应答机能使遥控指令正常工作(一般发自检指令50～100次)的最小输入电平，即为应答机的灵敏度。 5.7.4 信标频率测量 上行功率为额定电平，在应答机上行调频和上行调相状态下测量下行信标的频率精度和频率稳定度。 5.7.5 信标频谱测试 无上行载波时，编码遥测信号以额定调制度加到应答机下行载波上，在应答机输出口和地面接收机第二中放输出端用频谱仪观察下行频谱，记录各谱线的频率和分贝数。 5.7.6 应答机转发调制度测试 5.7.6.1 转发特性测试 在仅有测距信号时，转发特性是将遥测副载波断开，上、下行电平均比额定值高20dB，地面按额定调制度发高侧音测距信号，在应答机射频输入口和输出口分别利用频谱仪记录相应的上行频谱和下行频谱。 在有遥测信号时，转发特性是将遥测信号按额定调制度调到载波上，地面按额定调制度分别发高侧音和全侧音的测距信号，在应答机射频输入口和输出口分别利用频谱仪记录高侧音和全侧音的相应上行频谱和下行频谱。 5.7.6.2 转发调制度测试 在应答机上行调相、下行调相和上行调频、下行调相两种状态下测试，上行为额定电平，下行信号为额定信号噪声功率谱密度比，调整上行调制度，保证下行调制度额定值，记录此时各机的上下行信号的调制度值。 5.7.7 载波双捕性能测量 应答机接入测试系统，上行功率为额定电平，下行信号为额定信号噪声功率谱密度比，按适当的频率偏移要求，测量双向捕获时间，至少做10次，计算平均捕获时间。 5.7.8 频率突跳值测量 上行功率为额定电平，应答机处于锁相状态，上行载波频率做较小的约定变化，突然断上行或突然发上行情况下，检测星地设备的双捕性能。 5.7.9 应答机同步带及捕捉带测暈 上行功率为额定电平，应答机接入测试系统，由低至高和由高至低改变上行载频，测量应答机调相状态下工作的锁定、失锁点的频率，换算出应答机的同步带和捕捉带。 5.7.10 应答机积分器零点测量 应答机处于锁相状态时，改变测试上行频率，测出积分器电压为零时的上行频率，求出与标称点频率的差值。 5.7.11 应答机鉴频器零点测量 应答机处于鉴频状态时，改变测试上行频率，测出鉴频器电压为零时的上行频率，求出与标称点频率的差值。 5.7.12 距离零值测量 5.7.12.1 测控站(船)距离零值测量 在调相/调相状态下，按规定的上行电平、下行信号噪声功率谱密度比、载波中心频率和额定下行调制度，分别测量在“测量”和“自校”两种连接方式下的系统距离零值，经计算处理得到应答机的距离零值和各侧音间的相位差值(相位匹配值)。 在调频/调相状态下，按调频/调相状态的测试条件，在中频闭环的状态下测出“测量”(应答机、射频闭路)和“自校”两种连接方式下的系统距离零值，经计算处理得到应答机的距离零值。 5.7.12.2 发射场距离零值测量 测试条件同5.7.12.1条的规定。用发射星的测试设备对测控站(船)的卫星测控模拟器中的应答机测量，得到调相和调频方式时的距离零值、测距信号间的相位匹配值。 5.7.12.3 确定传递关系 调相方式距离零值比对，为测控站(船)与发射场测得的距离零值的差值。 调频方式距离零值比对，为测控站(船)与发射场测得的距离零值的差值。 相位匹配比对差值为测控站(船)与发射场在调相和调频方式下测得的测距信号各侧音的相位匹配值的差值。 5.7.12.4 测距离零值的比对校准 发射星应答机距离零值和相位匹配值的测定，用发射星测试设备分别测出调相、调频方式时的距离零值和各侧音间的相位匹配值。各测控站(船)按此测量值及传递关系，得到各自设备对发射星应答机的距离零值和相位匹配值。 5.7.12.5 对接试验时距离零值有关测试 a. 星地距离零值随上行电平的变化； b. 星地距离零值随下行电平的变化； c. 星地距离零值随上下行多卜勒的变化； d. 星地距离零值随上行调制度的变化； e. 星地距离零值12h漂移测试。 5.7.12.6 发射星应答机距离零值有关测试 用发射星测试设备测量下列距离零值有关参数： a. 距离零值随上行电平的变化； b. 距离零值随上行多卜勒的变化； c. 距离零值随上行调制度的变化； d. 距离零值随温度的变化。 5.7.13 遥控对接 5.7.13.1 主要功能测试 卫星测空模拟器与测控站(船)测控设备构成回路。按预先设计好的卫星遥控状态调整地面系统遥控设备，调整上、下行射频衰减器，使上、下行信号强度比额定值高20dB，选用“本控”工作方式，在各组副载频下将所有指令发送一遍，检查小回路比对和大回路比对是否正确。选用“远控”工作方式，重复上述试验。 5.7.13.2 比特误码率测试 星地设备加电预热2h，上、下行调制度额定，上行功率电平额定，下行电平比额定值高20dB，遥控台选用“远控”工作方式，上行多卜勒频偏为0，计算机以尽可能小的时间间隔连续发某条指令4h，由计算机统计比特误码率。上行多卜勒频偏分别为±60，±120，±180kHz时，计算机统计每种频偏下的比特误码率。 5.7.14 遥测对接 5.7.14.1 主要功能测试 卫星测控模拟器与测控站(船)测控设备构成回路。按预先设计好的卫星遥测状态调整地面系统遥测设备，调整下行射频衰减器，使下行信号强度比额定值高20dB，监视编码遥测波形和解调是否正确，检查副载波频率和波道分配是否正确。 5.7.14.2 编码遥测误码率测试 星地设备加电预热2h，无上行信号，调整下行射频衰减器，使下行信号强度为额定值，按预订的波道信号及码字，计算机统计2h的误码，得到遥测误码率。上行按额定电平、额定调制度发高侧音，计算机再统计2h的误码率。上行按额定电平、额定调制度发全侧音，计算机再统计2h的误码率。 5.7.15 星地天线极化对接 调整射频衰减器，使上、下行信号电平均比额定值高30dB。 地面分别以左、右旋圆极化接收，记录相应的下行信号强度。