硅振荡器时基对脉冲编码调制遥测系统的影响

The Effect of Silicon Oscillator Time-Base on the Telemetry System of PCM

高稳定度的石英基准因其易碎性在高过载遥测系统中的应用受到限制,而直接采用低稳定度硅振荡器PCM时基会造成乱码、失步等问题。从理论上分析了时基稳定度降低对脉冲编码调制遥测系统的影响,得出结论:码率降低对稳定度的要求相应降低;同步保持时间的长短与对稳定度要求的高低成正比;低稳定度硅振荡器时基不宜在高于500 kHz码率条件下工作。试验结果表明,在马歇特冲击过载30 000的条件下,按低稳时基所确定的码率与同步保持时间,数据能正确传输,能够满足引信遥测要求。

In high overload telemetry system, the application of high stability quartz time-base is re- stricted because of the fragility of material, but low stability time-base will bring the problems such as dis- order code, loss of synchronization. The effects of lowered stability time-base on the telemetry system of PCM are analysed in theory, it would come to the conclusion that the lower bit rate requires the lower sta- bility, synchronization hold-in time is longer when the higher the stability requirements, and the low sta- bility silicon oscillator time-base is not suitable to work under the higher than 500 kHz rate. The experi- ment results show that in the 30 000 Machete shock and overload conditions, the date can be transmitted correctly to meet the fuse telemetry requirements.