Key Factors Analysis and Design Optimization of RF Direct Sampling Receiver

With the widely use of RF Direct Sampling Receiver in HF reconnaissance domain, it becomes necessary to get the high point of its performance. This paper analyses the key factors that influence its sensitivity and dynamic range, and gives the analytic results based on the AD chip LTC2209. The paper designed the framework of the gain assignment, and used the feed-forward cancellation circuit. As a result, it improves the sensitivity, suppresses the spurious signals and develops the dynamic range. Proven by trails, the dynamic range of the RF Direct Sampling Receiver design introduced in this paper can reach 90dB, and can meet the need of wideband reconnaissance and the use of virtual narrow-band receiver.