测试软件原理培训资料.doc

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GIPB简介GPIB（General-Purpose Interface Bus通用接口总线）最初的GPIB是在1960年代后半期由惠普（当时称为HP-IB）开发的，用于连接和控制惠普制造的可编程仪器。在引进了数字控制器和可编程测试设备之后，对来自多个厂商的仪器和控制器之间进行标准高速通信接口的需求也应运而生。在1975年，美国电气与电子工程师学会（IEEE）发布了ANSI/IEEE标准488-1975，即用于可编程仪器控制的IEEE标准数字接口，它包含了接口系统的电气、机械和功能规范。最初的IEEE 488-1975在1978年经过修改，主要是出版声明和附录方面。现在这个总线已经在全世界范围内被使用，它有三个名字： 通用接口总线（GPIB） 惠普接口总线（HP-IB） IEEE 488总线 由于最初的IEEE 488文档并没有包含关于使用的语法和格式规范的叙述。这部分工作最终形成了一个附加标准IEEE 488.2，用于IEEE 488（被更名为IEEE 488.1）的代码、格式、协议和通用指令。IEEE 488.2并没有替换IEEE 488.1。许多设备还只是符合IEEE 488.1。IEEE 488.2是建立在IEEE 488.1的基础上的，它定义了设备接口功能的最小集合、一套通用的数据代码和格式、一个设备消息协议、一个常用通用设备指令集合以及一个全新的状态报告模型。在1990年，IEEE 488.2规范包含了用于可编程仪器控制的标准指令（SCPI）文档。SCPI定义了每个仪器级别（通常包含来自多个厂商的仪器）所必须遵守的专用指令。因此，SCPI保证了在这些仪器之间系统功能的完整性和可配置性。对于SCPI兼容的系统而言，不必再为每一个仪器学习一套新的指令集，从来自一家厂商的仪器更换到来自另一家厂商的仪器也变得更加容易。VISA (Virtual Instrument Software Architecture)VISA(Virtual Instrument Software Architecture虚拟仪器软件结构)是一个用来与各种仪器总线进行通讯的高级应用编程接口（API）。它不受平台、总线和环境的限制。换言之，与GPIB 设备进行通讯的程序，无论是在运行Windows 2000的机器上用LabVIEW开发出来的，还是在运行 Mac OS X的机器上用C语言编写的，都可以使用同一个API。它可驱动的I/O接口设备有GPIB 接口仪器，RS232接口仪器，VXI仪器模块等2. GPIB卡的安装和确认现场演示3. GPIB卡的编程接口简单介绍ni488.h头文件下的函数获取仪器句柄ibdev(int boardID, int pad, int sad, int tmo, int eot, int eos);写ibwrt(int ud, PVOID buf, long cnt);读ibrd(int ud, PVOID buf, long cnt);visa.h头文件下的函数获取仪器句柄viOpen(ViSession sesn, ViRsrc name, ViAccessMode mode, ViUInt32 timeout, ViPSession vi);写viPrintf(ViSession vi, ViString writeFmt, .);读viRead(ViSession vi, ViPBuf buf, ViUInt32 cnt, ViPUInt32 retCnt);4. 校准原理的介绍一.AFC（自动频率控制）校准 校准目的：校准AFCDAC值与TCVCXO输出频率（26MHz）之间的对应关系，使得测试接收信号的频率误差在允许范围之内。校准步骤：1. 控制综测仪Agilent 8960或者 R&S CMU200设定在BCCH（广播控制信道）中的某一个信道arfcn_C0_GSM（可以为1-124中的一个），并设定发射功率为PDL（dBm）；2. 设定模块中频部分的接收增益（siGain）为：-35-PDL（dB），AFC_DAC值为DAC1（由校准程序设定），软件发出AFC测试请求，在arfcn_C0_GSM信道上得到N_AFC个采样值；3. 等待CPU计算出接收I/Q信号的频率平均误差（Freq_Offset）：f1；4. 再设定模块中频部分的接收增益（siGain）为：-35-PDL（dB），AFC_DAC值为DAC2（由校准程序设定），这里DAC2DAC1，软件发出AFC测试请求，在测量信道上的到N_AFC个采样值；5. 等待CPU计算出接收I/Q信号的频率平均误差（Freq_Offset）：f2；6. 计算AFC DAC斜率为：Slope=（f1-f2）/（DAC2-DAC1）;由得到的Slope值及DAC1再计算Freq_Offset为“0”时，得到初始ADC值：AFC_DAC为：Use Default Value=f1/ Slope+DAC1;注：arfcn_C0_GSM、PDL、DAC1、DAC2、N_AFC均在meta配置文件（.CFG文件）中设定，以下是我们公司的校准参数：arfcn_C0_GSM = 65；定义用于AFC测试的信道为65;P_DL = -50； 定义综测仪发射功率为-50dBm；N_AFC = 10；定义AFC测量此时为10次；DAC1=4000；定义DAC1初始值为4000；DAC2=5000；定义DAC2初始值为5000；判断该项板测结果是否通过，即看得到测量结果值：AFC_Slope、AFC_DAC是否在上下限值之内，该限值也是在meta配置文件（.CFG文件）中设定，如下：AFC table/AFCDAC参数表MAX_INIT_AFC_DAC = 7000 MIN_INIT_AFC_DAC = 2000；（即定义INIT_AFC_DAC最大不超过7000，最小不小于2000）MAX_AFC_SLOPE = 6.0MIN_AFC_SLOPE =1.5；（即定义Slope值最大不超过6.0，最小不小于1.5）下图为测量频率平均误差对DAC值曲线，呈线性关系，直线的斜率为Slope。freq（Hz）DAC2DAC1Initial slope f20f1DAC校准LOG示例：-=AFC0, dac1 = 3895, dac2 = 4295: Enable = 1; DAC = 4460; Slope = 10.51=Write AFC to NVRAM SuccessSet Afc Dac Value Success=Write AFC DAC = 4460; Slope = 10.51-影响AFC的主要方面：1.26MHz时钟振荡器VCTCXO存在的不良，主要指存在频率偏差；2.射频接收路经存在的不良，如断路、器件虚焊、器件不良、及中频内部的频率解调电路存在的不良等；3.BB在RF接收部分存在的不良；二.RX PathLoss（接收路径损耗）校准校准目的：校准射频接收路径的损耗值。校准步骤：1. 控制控制综测仪Agilent 8960或者 R&S CMU200设定在信道ARFCNi（i由1到12），综测仪发射功率设定为PDL（dBm）；2. 设定模块中频部分的接收增益为：-35-PDL（dB），测量N_PM frames及M_PM samples；3. 等待CPU计算出接收的DSP功率，从而计算出射频接收端的功率值：PDL,req，从而估计出路径损耗为：Li（dB）=PDL-PDL,req；4. 重复1-3步，直到计算出GSM设定各信道的补偿值；5. 重复1-4步，直到GSM、DCS频段的补偿值；注：RxLoss校准信道在我们的校准程序和meta的.CFG文件中设置Max ARFCN=1,20,40,62,80,100,124,975,998,1023,-1;设定需校准的信道为1, 20, 40, 62, 80, 100, 124, 975, 998, 1023校准LOG示例：=Band = 0; Channel = 1; Loop:1; p_power = -494; AGC Gain/8 = 1.750000Band = 0; Channel = 20; Loop:1; p_power = -488; AGC Gain/8 = 1.000000Band = 0; Channel = 40; Loop:1; p_power = -487; AGC Gain/8 = 0.875000Band = 0; Channel = 62; Loop:1; p_power = -488; AGC Gain/8 = 1.000000Band = 0; Channel = 80; Loop:1; p_power = -493; AGC Gain/8 = 1.625000Band = 0; Channel = 100; Loop:1; p_power = -496; AGC Gain/8 = 2.000000Band = 0; Channel = 124; Loop:1; p_power = -493; AGC Gain/8 = 1.625000Band = 0; Channel = 975; Loop:1; p_power = -493; AGC Gain/8 = 1.625000Band = 0; Channel = 998; Loop:1; p_power = -497; AGC Gain/8 = 2.125000Band = 0; Channel = 1023; Loop:1; p_power = -495; AGC Gain/8 = 1.875000Band = 1; Channel = 512; Loop:1; p_power = -496; AGC Gain/8 = 2.000000Band = 1; Channel = 535; Loop:1; p_power = -497; AGC Gain/8 = 2.125000Band = 1; Channel = 585; Loop:1; p_power = -500; AGC Gain/8 = 2.500000Band = 1; Channel = 660; Loop:1; p_power = -496; AGC Gain/8 = 2.000000Band = 1; Channel = 700; Loop:1; p_power = -492; AGC Gain/8 = 1.500000Band = 1; Channel = 750; Loop:1; p_power = -491; AGC Gain/8 = 1.375000Band = 1; Channel = 790; Loop:1; p_power = -496; AGC Gain/8 = 2.000000Band = 1; Channel = 835; Loop:1; p_power = -502; AGC Gain/8 = 2.750000Band = 1; Channel = 855; Loop:1; p_power = -504; AGC Gain/8 = 3.000000Band = 1; Channel = 885; Loop:1; p_power = -503; AGC Gain/8 = 2.875000=其中，Channel=1代表校准的信道，即.CFG文件中的Max ARFCN，数字量1.7500代表得出的接收路径损耗值，即Li（dB）。影响RXPathLoss的主要方面：主要为射频接收路径存在的不良，如断路、虚焊、器件不良（如：射频开关、声表面滤波器、双工器等）、中频内LNA（低噪声放大器）不良等。三.APC（自动功率控制）校准校准目的：为了使各功率等级的最终输出符合ETSI规定的功率。基础知识介绍：APC D/A转换器为10位D/A转换器，位于CPU内部，即为10bit寄存器，范围是0-1023，共可代表1024个数值。APC DAC转换为模拟量，即VAPC的电压值范围是0.1V-2.2V，即：APC DAC的最小值（00 0000 0000）b（二进制）=000H（十六进制）=0（十进制） ，对应的VAPC输出电压为0.1V；APC DAC的最大值（11 1111 1111）b（二进制）=2FFH（十六进制）=1023（十进制）对应的VAPC输出电压为2.2V。因此该D/A转换器的分辨率为：（2.2V-0.1V）/1024=2.05mV，即APC DAC值每改变1，输出电压将改变2.05mV。以下表来说明功率等级-输出功率-VRAMP电压值-APC DAC之间的对应关系：功率等级输出功率(dBm)VRAMP电压值(V)APCDAC（十进制数）APC DAC（十六进制数）1950.28741408C1870.2977145911790.3121529816110.3305161A115130.3531172AC14150.3798185B913170.4126201C912190.4496219DB11210.4968242F210230.554327010E9250.62823061328270.72263521607290.83964091996310.98534801E05331.172157123B校准步骤：APC的校准原理简单的说就是：不断调整APC DAC数值（Facter），测量模块的功率输出，直至满足各功率等级的要求。校准LOG示例如下：-=*PCL = 5; TgtPwr = 32.50; Factor = 690; MeasPwr = 32.17; slope = 50PCL = 5; TgtPwr = 32.50; Factor = 707; MeasPwr = 32.26; slope = 197PCL = 6; TgtPwr = 31.00; Factor = 459; MeasPwr = 29.32; slope = 84PCL = 6; TgtPwr = 31.00; Factor = 601; MeasPwr = 31.64; slope = 61PCL = 6; TgtPwr = 31.00; Factor = 562; MeasPwr = 31.25; slope = 101PCL = 7; TgtPwr = 29.00; Factor = 334; MeasPwr = 24.58; slope = 34PCL = 7; TgtPwr = 29.00; Factor = 485; MeasPwr = 29.95; slope = 28PCL = 7; TgtPwr = 29.00; Factor = 458; MeasPwr = 29.28; slope = 40PCL = 8; TgtPwr = 27.00; Factor = 366; MeasPwr = 26.04; slope = 28PCL = 8; TgtPwr = 27.00; Factor = 393; MeasPwr = 27.12; slope = 25PCL = 9; TgtPwr = 25.00; Factor = 340; MeasPwr = 24.82; slope = 23PCL = 10; TgtPwr = 23.00; Factor = 298; MeasPwr = 22.65; slope = 19PCL = 10; TgtPwr = 23.00; Factor = 305; MeasPwr = 23.00; slope = 20PCL = 11; TgtPwr = 21.00; Factor = 265; MeasPwr = 20.45; slope = 15PCL = 11; TgtPwr = 21.00; Factor = 274; MeasPwr = 21.08; slope = 14PCL = 12; TgtPwr = 19.00; Factor = 244; MeasPwr = 18.92; slope = 13PCL = 13; TgtPwr = 17.00; Factor = 219; MeasPwr = 16.61; slope = 10PCL = 13; TgtPwr = 17.00; Factor = 223; MeasPwr = 17.00; slope = 10PCL = 14; TgtPwr = 15.00; Factor = 203; MeasPwr = 15.22; slope = 11PCL = 15; TgtPwr = 13.00; Factor = 178; MeasPwr = 11.84; slope = 7PCL = 15; TgtPwr = 13.00; Factor = 187; MeasPwr = 13.13; slope = 6PCL = 16; TgtPwr = 11.00; Factor = 174; MeasPwr = 11.19; slope = 6PCL = 17; TgtPwr = 9.00; Factor = 160; MeasPwr = 8.62; slope = 5PCL = 18; TgtPwr = 7.00; Factor = 151; MeasPwr = 6.62; slope = 4PCL = 19; TgtPwr = 5.00; Factor = 144; MeasPwr = 4.70; slope = 3*PCL = 0; TgtPwr = 29.50; Factor = 730; MeasPwr = 28.88; slope = 50PCL = 0; TgtPwr = 29.50; Factor = 761; MeasPwr = 29.25; slope = 83PCL = 1; TgtPwr = 28.00; Factor = 656; MeasPwr = 28.12; slope = 92PCL = 2; TgtPwr = 26.00; Factor = 461; MeasPwr = 23.89; slope = 46PCL = 2; TgtPwr = 26.00; Factor = 559; MeasPwr = 26.45; slope = 38PCL = 2; TgtPwr = 26.00; Factor = 541; MeasPwr = 26.03; slope = 43PCL = 3; TgtPwr = 24.00; Factor = 453; MeasPwr = 23.68; slope = 37PCL = 3; TgtPwr = 24.00; Factor = 465; MeasPwr = 23.99; slope = 38PCL = 4; TgtPwr = 22.00; Factor = 389; MeasPwr = 21.42; slope = 29PCL = 4; TgtPwr = 22.00; Factor = 406; MeasPwr = 22.15; slope = 23PCL = 5; TgtPwr = 20.00; Factor = 356; MeasPwr = 20.15; slope = 25PCL = 6; TgtPwr = 18.00; Factor = 302; MeasPwr = 17.52; slope = 20PCL = 6; TgtPwr = 18.00; Factor = 312; MeasPwr = 18.02; slope = 20PCL = 7; TgtPwr = 16.00; Factor = 271; MeasPwr = 15.63; slope = 17PCL = 7; TgtPwr = 16.00; Factor = 278; MeasPwr = 16.02; slope = 17PCL = 8; TgtPwr = 14.00; Factor = 243; MeasPwr = 13.60; slope = 14PCL = 8; TgtPwr = 14.00; Factor = 249; MeasPwr = 14.04; slope = 13PCL = 9; TgtPwr = 12.00; Factor = 222; MeasPwr = 11.79; slope = 12PCL = 10; TgtPwr = 10.00; Factor = 200; MeasPwr = 9.32; slope = 8PCL = 10; TgtPwr = 10.00; Factor = 206; MeasPwr = 10.33; slope = 5PCL = 10; TgtPwr = 10.00; Factor = 204; MeasPwr = 9.86; slope = 4PCL = 11; TgtPwr = 8.00; Factor = 196; MeasPwr = 8.78; slope = 7PCL = 11; TgtPwr = 8.00; Factor = 190; MeasPwr = 8.24; slope = 11PCL = 12; TgtPwr = 6.50; Factor = 170; MeasPwr = 4.90; slope = 5PCL = 12; TgtPwr = 6.50; Factor = 179; MeasPwr = 6.53; slope = 5PCL = 13; TgtPwr = 5.00; Factor = 171; MeasPwr = 5.11; slope = 5PCL = 14; TgtPwr = 3.50; Factor = 162; MeasPwr = 3.20; slope = 4PCL = 15; TgtPwr = 2.00; Factor = 157; MeasPwr = 1.95; slope = 4Write GSM AFC TxOffset = 1; DCS AFC TxOffset = 1; PCS AFC TxOffset = 751; G850 AFC TxOffset = 0=-影响APC的主要方面：1. 射频发射路径存在的不良，如器件不良（功放、射频开关等）、发射路径存在的断路、器件焊接不良、阻抗不匹配等；2. 中频内部的发射部分存在的不良，如内部TXVCO部分的不良；3. 功率控制部分的不良，主要指相关的功放控制信号存在的不良；4. 参考时钟TCXO（26MHz）出现较大的频率偏差；5. CPU内部射频发射部分存在的不良；四.ADC校准校准目的：校准模块检测到的供电电压与实际的电压显示之间的关系，使电压的显示与实际的电压一致。校准步骤：以供电电压校准为例说明1. 命令程控电源输出电压为ADC_V1（如数字量3400），实际输出为ADC_Measure_Voltage_0（如模拟量3.4V），即直接加在供电端的电压为3.4V；2. 命令模块通过电池检测通道（ADC0_I-）来进行CPU检测信号输入端的电压值，为BATTERY_ADC_Output_0；3. 命令程控电源输出电压为ADC_V2（如数值量4200），实际测量可编程电源输出为ADC_Measure_Voltage_1（如模拟量4.2V），即直接加在供电端的电压为4.2V；4. 命令模块通过电池检测通道（ADC0_I-）来进行CPU检测信号输入端的电压值，为BATTERY_ADC_Output_1；5. 计算CPU检测ADC信号与电源输出电压信号曲线的斜率：Slope(BATTERY_CHANNEL)=( ADC_Measure_Voltage_1- ADC_Measure_Voltage_0)/( BATTERY_ADC_Output_1- BATTERY_ADC_Output_0);Of