【摘要】 通过钻井液压力DPSK信号的相位解调及旋转阀转速控制脉冲的重构,可以恢复信号调制过程中的数据编码,但解调系统产生的固有干扰及信号噪声会对旋转阀转速控制脉冲重构的正确性产生很大影响。鉴于此,基于无码间串扰单极性脉冲PCM(脉码调制)系统的误码率分析,通过建立重构的旋转阀转速控制脉冲信噪比数学模型,对重构脉冲的误码率进行了理论研究。研究结果表明,旋转阀转速控制脉冲的重构会受到解调系统产生的固有随机干扰及信号噪声的双重影响,二者通过影响重构脉冲的幅度信噪比使误码率增大。误码率的数值仿真结果与理论计算结果基本一致,验证了理论分析的正确性。研究结果为解调系统参数的优化设计及信号噪声的控制研究提供了理论指导,并且为钻井液压力DPSK信号传输的可靠性评估提供了理论基础。更多还原

【Abstract】 The data coding in signal modulation process could be restored by drilling pressure DPSK signals phase demodulation and the reconstruction of the rotary valve control pulse. But the inherent interference of the demodulation system and signal noise could significantly impact the correctness of the reconstruction of the rotary valve control pulse. To address the issue,based on the bit error rate( BER) analysis of single polarity pulse PCM( pulse code modulation) system without intersymbol interference,a signal to noise ratio( SNR) mathematical model for the reconstructed rotary valve control pulses has been established to theoretically study the BER of the reconstructed impulse. The research results indicate that reconstruction of the rotary valve control pulses will be affected by inherent random interference produced in the demodulating system and noise,leading to higher BER by impacted reconstruction pulse amplitude SNR. Numerical simulation results show that the theoretical computed BER of the reconstructed pulses and the simulated one are nearly the same,thus validating the theoretical analysis. The research could provide theoretical guides to parameter optimization of the demodulating system and signals noise control,and present theoretical basis to reliability evaluation on transmission of drilling pressure DPSK signals.更多还原