无线电工程
無線電工程
무선전공정
Radio Engineering
2015年
10期
38-40
,共3页
QPSK%相位噪声%星座图%LDPC
QPSK%相位譟聲%星座圖%LDPC
QPSK%상위조성%성좌도%LDPC
QPSK%phase noise%constellation diagram%LDPC
QPSK具有误码性能好、 带宽利用率高等优点, 但工程应用中复杂的信号处理带来的相位噪声直接影响了其性能. 建立了相位噪声的QPSK模型, 从理论上分析了相位噪声对QPSK解调性能的影响. 指出相位噪声会导致QPSK调制信号星座图的旋转, 导致系统解调性能的下降, 并对相位噪声干扰下QPSK解调误码率性能进行了仿真和分析. 最后指出选择合适的低密度奇偶校验 ( LDPC) 码可以有效减小相位噪声对QPSK解调性能的影响, 提高误码性能, 并且通过仿真研究了LDPC编码改善误码特性的适用条件.
QPSK具有誤碼性能好、 帶寬利用率高等優點, 但工程應用中複雜的信號處理帶來的相位譟聲直接影響瞭其性能. 建立瞭相位譟聲的QPSK模型, 從理論上分析瞭相位譟聲對QPSK解調性能的影響. 指齣相位譟聲會導緻QPSK調製信號星座圖的鏇轉, 導緻繫統解調性能的下降, 併對相位譟聲榦擾下QPSK解調誤碼率性能進行瞭倣真和分析. 最後指齣選擇閤適的低密度奇偶校驗 ( LDPC) 碼可以有效減小相位譟聲對QPSK解調性能的影響, 提高誤碼性能, 併且通過倣真研究瞭LDPC編碼改善誤碼特性的適用條件.
QPSK구유오마성능호、 대관이용솔고등우점, 단공정응용중복잡적신호처리대래적상위조성직접영향료기성능. 건립료상위조성적QPSK모형, 종이론상분석료상위조성대QPSK해조성능적영향. 지출상위조성회도치QPSK조제신호성좌도적선전, 도치계통해조성능적하강, 병대상위조성간우하QPSK해조오마솔성능진행료방진화분석. 최후지출선택합괄적저밀도기우교험 ( LDPC) 마가이유효감소상위조성대QPSK해조성능적영향, 제고오마성능, 병차통과방진연구료LDPC편마개선오마특성적괄용조건.
QPSK modulation technology is widely applied for its many merits such as ideal bit error rate and higher spectrum efficiency.But the phase noise brought by the complicated signal processing can affect the performance of QPSK demodulation.In this paper,the model of QPSK influenced by phase noise is given.Based on the analysis of the phase noise effect on QPSK demodulation,the result is presented that the phase noise can result in the constellation diagram point shift, which worsens the performance of QPSK system.A simulation is done to validate the effect of phase noise on the bit error rate(BER)performance.Finally,the paper finds out that the Low Density Parity Check Codes(LDPC)can reduce the influence of the phase noise on QPSK demodulation,improving the BER performance,and through the simulation shows the applicable condition of the LDPC code to improve the BER performance.
