信号处理
信號處理
신호처리
SIGNAL PROCESSING
2015年
4期
483-489
,共7页
认知无线电%频谱感知%特征矢量%子空间投影算法
認知無線電%頻譜感知%特徵矢量%子空間投影算法
인지무선전%빈보감지%특정시량%자공간투영산법
cognitive radio%spectrum sensing%eigenvector%subspace projection algorithm
为了发现空间中的“频谱空洞”而加以利用以使频谱利用率最大化,频谱感知技术得到了广泛关注。已有基于特征矢量的频谱感知算法因涉及大量特征值分解运算导致算法运算量大,不适应实时检测。本文提出的频谱感知算法利用信号子空间和噪声子空间之间的正交性,将次用户接收信号分别投影到上述子空间,根据投影值的差异实现快速频谱感知。理论分析和仿真结果表明本文提出的算法与已有算法相比有效降低了运算量,检测性能不受噪声不确定度影响、不需要预知主用户先验知识和噪声方差,且低信噪比、小采样情况下有更优越的检测性能。
為瞭髮現空間中的“頻譜空洞”而加以利用以使頻譜利用率最大化,頻譜感知技術得到瞭廣汎關註。已有基于特徵矢量的頻譜感知算法因涉及大量特徵值分解運算導緻算法運算量大,不適應實時檢測。本文提齣的頻譜感知算法利用信號子空間和譟聲子空間之間的正交性,將次用戶接收信號分彆投影到上述子空間,根據投影值的差異實現快速頻譜感知。理論分析和倣真結果錶明本文提齣的算法與已有算法相比有效降低瞭運算量,檢測性能不受譟聲不確定度影響、不需要預知主用戶先驗知識和譟聲方差,且低信譟比、小採樣情況下有更優越的檢測性能。
위료발현공간중적“빈보공동”이가이이용이사빈보이용솔최대화,빈보감지기술득도료엄범관주。이유기우특정시량적빈보감지산법인섭급대량특정치분해운산도치산법운산량대,불괄응실시검측。본문제출적빈보감지산법이용신호자공간화조성자공간지간적정교성,장차용호접수신호분별투영도상술자공간,근거투영치적차이실현쾌속빈보감지。이론분석화방진결과표명본문제출적산법여이유산법상비유효강저료운산량,검측성능불수조성불학정도영향、불수요예지주용호선험지식화조성방차,차저신조비、소채양정황하유경우월적검측성능。
Spectrum sensing technology had been widely concerned in order to find the avallable spectrum holes to im-prove the spectrum utilization.Because of the existing algorithms that based on the eigenvector involved a large number of eigenvalue decomposition,so they didn’t fit for the real-time detection.Utilized the orthogonality between the signal sub-space and the noise subspace,the proposed spectrum sensing algorithm projected the received signal of the secondary users (SU)on the two subspace and achieved fast spectrum perception based on the differences of the projection values.The the-oretical analysis and the simulation results show that the proposed algorithm reduces the computational complexity effectively and it is robust to the noise uncertalnty and need neither the prior knowledge of the primary user(PU)nor the noise vari-ance.Furthermore,it can achieve a better detection performance with low SNR and small sampling.