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本文在文献［１］研究Ｐ码波形自相关函数旁瓣结构的基础上，从Ｐ码波形导出了一类能实现低距离旁瓣的多相码“波形对”。在零多普勒频移的条件下，该类“波形对”能以少量信噪比损失为代价使脉压输出波形的主旁瓣比与码序列长度相等，也就是说，从主旁瓣比的角度讲，该类“波形对”可以等效为相应长度的多相巴克码波形。另外，我们还研究了该类“波形对”的多普勒特性，数字仿真结果表明，由Ｐ３或Ｐ４码导出的“波形对”脉压结果的主旁瓣比对多普勒不敏感，在ｆｄ＝０～０．０５Ｂ范围内，最大Ｓ／Ｎ损失为３ｄＢ，最小Ｓ／Ｎ损失为０．８７ｄＢ，呈现周期性。
Based on the study of the sidelobe structure of the P code waveform autocorrelation function in [1], this paper derives a kind of “waveform pair” of polyphase code that can realize low range sidelobe from the P code waveform. With zero Doppler shift, this type of “waveform pair” can equalize the main sidelobe of the pulse-pressure output waveform with the length of the code sequence at the expense of a small loss of signal-to-noise ratio, that is, For the sake of comparison, this type of “waveform pair” can be equivalent to a polyphase bar code waveform of the corresponding length. In addition, we also study the Doppler characteristics of this type of “waveform pair”. The numerical simulation results show that the main sidelobe of the “waveform pair” pulse pressure derived from P3 or P4 code is insensitive to Doppler. fd = 0 ~ 0.05B, the maximum S / N loss is 3dB, the minimum S / N loss is 0.87dB, showing periodicity.