Compression of Location Signal on Base of Chirp-Signals and Noise-Like Codes

摘要

Methods of digital locations have superiority over analog methods because they ensure higher resolution, reliability and elasticity in adaptive sphere. In location the short noise-like codes are widely used apart from chirp-signals. The connection of these kinds of signals may assure additional advantages but it was not studied sufficiently up till now. The purpose'of this paper is to analyze the compression of proposed kinds of signals. Simultaneous use of linear modulation of frequency of signal with code manipulation was suggested. This paper presents nonlinear methods to increase the ratio of the main lobe to side lobes of compressed signal (SNR) in conditions of disturbances. This approach was analyzed with use of binary code of 24 bits long and short chirp signals. Noise-like codes allow increasing reliability of identifying signal because transformation of one or more code symbols can insignificantly decrease SNR on output of matching-filter (MF). Besides, it is possible to change such codes in real time to protect the receiver from unexpected artificial and natural disturbances. This paper presents structures of receiving systems based on use of matching filters, which realize the approach discussed.