【摘要】 理想情况下,四相相移键控(Quadrature phase shift keying,QPSK)中的中频频率变换不会使系统的误码率产生恶化,但是,由于实际的本振中存在相位噪声,在进行频率变换时,会使系统的误码率增大。在QPSK系统中,关于相位噪声对系统性能影响的分析一直是研究的难点。针对此问题,本文给出了在QPSK调制解调系统中,本振相位噪声引起的误码率恶化的理论计算方法,并对此进行了仿真验证。结果表明仿真得到的结果和理论方法计算得到的结果一致。更多还原

【Abstract】 In the ideal situation,the frequency conversion cannot degrade the bit error rate(BER) of the quadrature phase shift keying(QPSK) system.However,because of the existence of the phase noise in the real oscillators,the frequency conversion increases the BER of QPSK system.In QPSK system,it is very difficult to analyze the effect of the phase noise on the system performance.To solve the problem,an approximate theoretical computation method for BER is proposed and simulation experiments are made.The result indicates that the simulation results are in agreement with the results derived from the theoretical computation.更多还原