The Large Dynamic High-sensitivity Digital Receiver Technology Research

Based on wide dynamic range and high sensitivity technology, wideband digital Electronic Warfare (EW) receiver is able to have wide monitoring band, high sensitivity, high intercept probability, wide dynamic range, and the ability of the multi-signal processing at one time. It can scout many kinds of signals, such as radar and communication signals. The dynamic range and the sensitivity are the key characters of wideband digital EW receiver. Wide dynamic range technology is the feasible scheme to resolve the dynamic gap between the dynamic range of radio front end and the dynamic range of high speed Analog Digital Converter (ADC). High sensitivity and low power signals receiving can be realized by the low noise figure technology. In this dissertation, the dynamic range and the sensitivity of EW receiver are studied and validated. The parameters related to the dynamic range and the sensitivity are researched, and a parallel amplifier structure for increasing the dynamic range of EW receiver effectively with little impact on the receiver sensitivity is presented, as well as the implementation of the experimental. The main works of the dissertation are as follows.(1) Signal characteristics under modern electronic reconnaissance environment are analyzed. It is pointed out that wideband digital receiver must satisfy wide monitoring band, wide dynamic range and high sensitivity, et al. The main characters of the wideband EW receiver are introduced briefly. A scheme of the channel wideband digital receiver is given.(2) The sensitivity technologies are analyzed, and the methods of improving the receiver noise figure are studied. Based on the electronic element reasonable application, the radio front end noise is decided by the link of the elements.(3) The corresponded parameters for the dynamic range improvement are analyzed. The traditional methods of increasing the dynamic range of the receivers, such as Sensitivity Time Control (STC), Automatic Gain Control (AGC), and band-pass Intermediate Frequency (IF) limiting, are researched. It is pointed out the limitation of the traditional technologies in increasing the dynamic range in wideband digital EW...