Narrowband Interference Suppression Techniques Based On Recursive Least Squares Method Of Spread Spectrum Communication System

Spread Spectrum technology for its intrinsic interference suppression characteristics obtained a rapid development, the Direct Sequence Spread Spectrum communication (such as Sequence intention, DSSS) system is a typical Spread Spectrum communication system. The DSSS system of the anti-jamming ability of Spread Spectrum processing, can gain by adding bandwidth decided to increase, but the actual Spectrum gain due to the limited bandwidth and technology Co., LTD. Is the spread-spectrum gain NBD due to its power spectral density is much higher than the broadband interference, so it is destructive to the DSSS system, when a stronger strong-narrow band exists only on the system to ensure the anti-interference ability of high quality communication system, and may even cause disrupting communication system. Therefore, the effective narrowband interference suppression technique has the significant practical significance to this problem. This article is for more detailed study.Small signal spectrum decline does not make serious distortion of spectrum. Multipath interference is due to the radio waves propagation process of the reflector (mountains, building), to accept signal proportional, cause intersymbol distortion caused by noise and increase. And straight system can use these interference energy to improve the performance of the system. Straight system in addition to general communication system requires synchronization, must also complete pseudo random synchronization, to accept machine with the synchronization of pseudo random yards after go to accept signal correlation algorithm. Straight with pseudo-random code system requirements, the longer the word is high, synchronization and synchronization time is long.Straight and frequency hopping system have strong performance of confidentiality. For direct system, the bandwidth is very wide, spectral density low and even drowned in the noise. It is difficult to check the existence of signal.The linear filter technology, the time domain and frequency domain of nonlinear filtering technology transformation of the traditional filter technology in narrowband interference filtering method of certain limits and defects, this article will use the recursive least squares and frequency conversion technology to these limitations and defects do some little improvement. The computer simulation results show that our method has good performance.