基于HHT的ACARS基带信号处理方法的研究

Method of ACARS Baseband Signal Processing Based on Hilbert-Huang Transform

针对目前ACARS基带信号处理的方法,将Hilbert-Huang变换应用于ACARS报文的解析中。以采集到的民航飞机下行的ACARS报文信号为数据源,利用经验模式分解法EMD将报文信号分解成有限个固有模态函数IMF,从而根据Hilbert变换求出每个固有模态函数IMF的瞬时频率,结合ARINC-618协议定义的ACARS报文信号数据传输机制与编码特点,完成了报文信号的译码。将一种新的方法运用到ACARS基带信号处理中,可以有效地消除ACARS基带信号失真的影响,具有较强的抗信号漂移能力。通过与权威的译码系统译码得到的结果对比,表明算法具有良好的工程应用价值。

Aimed at the current analytic method of the ACARS baseband signal processing, the Hilbert- Huang transform is applied to Parameter identifying of the ACARS message. The ACARS signals collected from.the civil aviation planes are taken as the data source. And the signals can be decomposed into a fi- nite number of intrinsic mode functions by the empirical mode decomposition. Then the frequency of each IMF will be acquired according to Hilbert transform. Combined with data transmission and encoding char- acteristic of ACARS signal defined in ARINC- 618, the decoding of the message signal is completed. A new method is applied to the ACARS baseband signal processing, it can effectively eliminate the influence of ACARS baseband signal distortion, and has strong ability to resist signal drift. Compared with the re- suits obtained from the authoritative decoding system, the algorithm presented in this article showed a good performance in engineering application.