大带宽采样下通用接收机ADC设计

为了解决宽带采样通用接收机中模数转换器(ADC)的抗干扰问题，定量分析采样带宽内存在不同功率的其他信号时对有用信号量化时造成的ADC输出信噪比的损失，对ADC输出信噪比的损失与输入有用信号信噪比、中频预选滤波器带宽内信号的信干噪比、输入信号功率、有用信号带宽、ADC采样带宽、ADC量化位数的关系进行理论分析与推导，并进行多场景下的仿真验证。结果表明，研究中对ADC输入和量化噪声的理论分析及推导是正确的，对于卫星通信中带宽20 kHz的典型信号，当要求输出信噪比损失小于0.1 dB时，要实现20，30和40 dB的抗干扰能力所需要的最小量化位数分别为8位，9位和10位。宽带采样下接收机ADC的设计，可获得最佳的性价比，并利于在工程中控制成本，对于宽窄带兼容接收有一定的工程意义。

Design of a universal receiver ADC with large bandwidth sampling

In order to solve the anti-interference problem of ADC in wideband sampling universal receiver, the loss of ADC output signal to noise ratio caused by the quantization of useful signals when other signals of different power exist in sampling bandwidth was quantitatively analyzed. The relationship among signal to noise ratio of input useful signal, signal to noise ratio of signal in IF preselected filter bandwidth, input signal power, useful signal bandwidth, ADC sampling bandwidth and ADC quantization digit was theoretically analyzed and deduced, and the simulation verification in multiple scenarios was conducted. The correctness of the theoretical analysis and derivation is verified by simulation in multiple scenarios.The results show that the theoretical analysis and derivation of ADC input and quantization noise are corrent.For the typical signal with a bandwidth of 20 kHz in satellite communication, when the output SNR loss is required to be less than 01 dB, the minimum quantization bits required to achieve the anti-jamming capability of 20 dB, 30 dB and 40 dB are 8, 9 and 10 bits respectively. Therefore the design of the receiver ADC under brood band sampling can get the best cost preformance and is beneficial for the cost control in engineering,which has certain engineering significance for wide and narrow band compatible reception.