Achievable bit rates of cognitive user with Vandermonde precoder in cognitive radio network  

作　　者：XU XiaoRong ZHANG JianWu ZHENG BaoYu 

机构地区：[1]College of Telecommunication Engineering, Hangzhou Dianzi University, Hangzhou 310018, China [2]Institute of Signal Processing and Transmission, Nanjing University of Posts and Telecommunications Nanjing 210003, China

出　　处：《Science China(Information Sciences)》2011年第7期1471-1480,共10页中国科学（信息科学）（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant No.60972039);Zhejiang Natural Science Foundation for Talents (Grant No.R105473);Young Staff Startup Research Foundation of Hangzhou Dianzi University (Grant No.KY085610034)

摘　　要：In cognitive radio network （CRN） where primary user （PU） and secondary user （SU） wish to communicate with their corresponding receivers simultaneously over frequency selective fading channels, the interference between PU and SU should be eliminated in order to realize spectrum sharing. Precoder division multiple access （PDMA） that implements Vandermonde precoder in cognitive orthogonal frequency division multiplexing （OFDM） is proposed, which benefits from the frequency selectivity of the cognitive channel to form a frequency beam-former. Vandermonde precoder enables SUs to achieve higher bit rate with optimal power allocation strategy under the condition of PU interference constraint. Numerical and simulation results are presented to prove theoretical derivations. It is shown that, achievable bit rates （ABR） of SU could be achieved with optimal power allocation scheme in CRN. Meanwhile, it is also verified that, with Vandermonde precoder to form PDMA, SU＇s signal-to-noise ratio （SNR） and the target rate of PU could impact the ABR of SU significantly in CRN.In cognitive radio network （CRN） where primary user （PU） and secondary user （SU） wish to communicate with their corresponding receivers simultaneously over frequency selective fading channels, the interference between PU and SU should be eliminated in order to realize spectrum sharing. Precoder division multiple access （PDMA） that implements Vandermonde precoder in cognitive orthogonal frequency division multiplexing （OFDM） is proposed, which benefits from the frequency selectivity of the cognitive channel to form a frequency beam-former. Vandermonde precoder enables SUs to achieve higher bit rate with optimal power allocation strategy under the condition of PU interference constraint. Numerical and simulation results are presented to prove theoretical derivations. It is shown that, achievable bit rates （ABR） of SU could be achieved with optimal power allocation scheme in CRN. Meanwhile, it is also verified that, with Vandermonde precoder to form PDMA, SU＇s signal-to-noise ratio （SNR） and the target rate of PU could impact the ABR of SU significantly in CRN.

关 键 词：achievable bit rates （ABR） Vandermonde precoder precoder division multiple access （PDMA） optimal power allocation cognitive radio network （CRN） 

分 类 号：TN929.5[电子电信—通信与信息系统] TP391[电子电信—信息与通信工程]