Study On Blind Detection For Communication Signals And Broadband Receiver

With the development of communication technology, in electronic reconnaissance systems, efficient reconnaissance and receiving for broadband multi-signals are essential, and blind detection for weak signals is necessary. High-performance broadband receiver is necessary to complete the whole probability of receiving. Meanwhile, low computation is very important for the receiver. Blind detection for weak signals is not based on knowledge of the source signals and the transmission channel. It is solely on the basis of the observation signals in order to following processing. Therefore, the researches for broadband receive and blind signal detection are very important practical significance.On basis of the introduction of broadband receivers and blind signal detection theory, the article mainly study high-performance structure of digital channelized receiver based on polyphase filters. In such a channelized receiver, filter and down converter are back of the sampler. And the receiver is completed based on FFT. Because of this structure, the computation is simplified and the achievability is advanced. But the receiver with such a structure has two problems, namely, blind-area and cross-channel signal. The solution of these two problems is proposed in this article. On the other hand, an iterative algorithm based on constant false alarm rate (CFAR) in blind signal detection fields is presented in this paper. This algorithm can estimate the statistical characteristic of the intermediate frequency noise. It extracts signals from noise on basis of analyzing statistical characteristic. It is easy to know whether the target signals exist or not.The achievability and low-complexity of the receiver have been verified by MATLAB simulation and DSP software simulation. Meanwhile, the blind signal detection algorithm which is proposed in this article has been proved to be a simple and well self-adaptive method. The performance of this algorithm has been improved compared with the traditional CFAR detection algorithm.