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一、引言用短波单边带电台及短波电离层反射信道传输数字信号,其性能与传输数据的其它信道(如散射、卫星等)相比,几乎是最不理想的,这是由于短波信道在传输数字信号过程中,产生较严重的快乘性干扰,使波形产生较大的畸变与严重的码间串扰所致。如目前使用的单边带电台,用话路传送双路移频报,其传输速率只有100比特/秒,而误码率却达到10~(-2)～10~(-3)
I. INTRODUCTION Transmission of digital signals over shortwave single-sideband stations and short-wave ionospheric reflection channels is almost the least desirable compared to other channels that transmit data (such as scattering, satellites, etc.) due to the shortwave channel at In the process of transmitting digital signals, more severe multiplicative interference is generated, resulting in larger distortion of the waveform and serious crosstalk between codes. For example, the currently used single-sideband radio station transmits two-way frequency shift reports by using voice channels, and the transmission rate is only 100 bits / second while the bit error rate is 10 -2 to 10 -3.