摘要
π/4-DQPSK是一种比较适合在移动通信中使用的调制方式,传统的差分检测方法误码率比QPSK相干解调恶化大约2.3dB,利用判决反馈的信号估计出参考信号,对π/4DQPSK信号进行多码元差分检测。该方法与传统的检测方法相比,不需要增加乘法运算,易于工程实现。计算机仿真结果表明在高斯信道中,相对于传统的差分检测方法,无频率偏移时,判决反馈多码元差分检测方法在误码率为10-4时,性能改善大约1.6dB;剩余频率偏移值为符号速率的0.5%时,性能改善约1dB。
The π/4 - DQPSK modulation mode is suitable to be used in mobile communications. The traditional differential detection is 2.3 dB inferior to coherent QPSK. In the paper, the multiple-symbol differential detection with reference signal estimation based on the feedback of past detected symbol is presented for π/4 - DQPSK. Compared with the traditional differential detection, this method doesn＇ t need increase of multiplication and can be realized easily. In the AWGN channel, the computer simulation result indicates that in case of no frequency offset, compared with the traditional differential detection, the performance is improved by 1.6dB with bit error rate of 10e-4;when frequency offset is 0.5% of symbol frequency,compared with the traditional differential detection,the performance is improved by ldB with bit error rate of 10e- 4.
出处
《无线电通信技术》
2009年第1期33-34,44,共3页
Radio Communications Technology
