The Research And Implementation Of Key Techniques For Digital ICS Wireless Communication Repeater

After next generation wireless communication system comes into business, operators presented an upsurge in next generation network construction. However, if wireless communication networks are constructed only by setting up base stations densely, an unnecessary resource waste will be raised. As a supplement of base stations, digital ICS(Interference Cancel System) wireless communication repeater plays an important role in the network construction.After introducing the basic knowledge of ICS repeater, the preprocessing technologies and RLS(Recursive Least Squares) adaptive filtering algorithms are primarily researched in this thesis.In the research of preprocessing technologies, time delay estimation of echo signal is studied, and multipath location estimation of echo channel is proposed in this thesis. In the time delay estimation of echo signal, generalized cross correlation is used for improving the accuracy of time delay estimation. And in the multipath location estimation of echo channel, by making use of the prior knowledge of previous paths, the SNR(Signal Noise Rate) of following path signals are enhanced, and a better accuracy of multipath location estimation is achieved.The research of RLS adaptive filtering algorithms contains the study of existing RLS algorithms and the improvement of them. Traditional RLS algorithm, FTRLS(Fast Transversal RLS) algorithm and SFTRLS(Stabilized FTRLS) algorithm are introduced firstly. Then, based on the characteristics of echo channel, linear constrained RLS algorithm and linear constrained SFTRLS algorithm are proposed in this thesis.MATLAB simulation results of the preprocessing technologies and RLS adaptive filtering algorithms show that satisfactory performances have been achieved.At last, based on FPGA, the key modules of preprocessing technologies and linear constrained SFTRLS algorithm are realized. The result shows that the multipath location estimation of echo channel proposed in this thesis is helpful to save hardware resources.