Research On Detection And Parameter Estimation Of Frequency Hopping Signal Based In Compressive Domain

With advantages such as high security,low probability of interception and good anti-jam performance,Frequency-Hopping(FH)communication has been widely used in many civil and military areas.With the development of communication technology,the bandwidth becomes larger and hopping rate becomes higher which leads to the higher sampling rates and larger quantity of data.The most prominent advantage of Compressed Sensing(CS)technology is that it can sample the sparse signal at the sampling rate far below Nyquist and ensure that there is no loss of information in the signals,so CS provides a new solution for the sample and process problem of wideband signals.Based on the research of CS theory,this paper introduces the wideband signals' sparse representation,the process of compressed sampling,the reconstruction algorithm and the analog to information converter(AIC).Then analyze the sparsity of narrow-band and wide-band FH signals,and verify the feasibility of applying CS to the FH signals capture system.Carry on the key research of FH signal's detection and estimation problem based in compressive domain.This paper puts forward a FH signal detection algorithm based on compressed frequency related-index characteristics(CS-FD)and a parameter blind estimation algorithm based on the compressed numeral characteristics(CS-PBE).At last,this paper introduces the design and implementation wide-band FH signals processing system based in compressed domain.And use the actual compressed sampling values obtained by the system to make simulation of CS-PBE algorithm.The innovations are summarized as follows:Firstly,in view of FH signal detection in complex electromagnetic environment conditions(the received signal is fixed with frequency-fixed interference,swept-frequency interference and short burst interference),this paper puts forward the CS-FD algorithm.By the use of compressed frequency related-index characteristic of the signals,this algorithm deduces the characteristics' difference between FH signals and interferences.Then we can realize the detection and recognition of FH signal depending on the compressed frequency related-index characteristics.The algorithm is directly based on compressed sampling values,can effectively improve the accuracy and efficiency of the FH signal detection.Secondly,in view of the FH signal parameter estimation problem mixed with gaussian white noise,the CS-PBE algorithm is proposed by the use of FH signals' sparsity in the frequency domain on the premise of not completely reconstruct the original signal.This algorithm can accurately estimate the hopping time and carrier frequency.This algorithm uses compressed sampling values directly,and can satisfy the real-time processing of FH signals because of the small computational complexity and low algorithm complexity.Finally,based on the research and development of wideband signal sampling system using CS theory,this paper complete the design and configuration of 2-port RAM modules.The system formulate and implement the data sharing and communication protocol between FPGA and ARM by the use of 2-port RAM.Then achieve the sending and receiving wideband CS measurement waveform by the use of AD9739 A.And realize the real-time collection of the compressed sampling values by the acquisition card through the control of FPGA.At last,based on the developed CS hardware platform,practical FH signals are compressed sampled.Then make a simulation verification of CS-PBE by using the compressive measurements.The results show that the algorithm is effective.