The Research Of The Digital Receiver

Modern electronic receivers are under more and more complex electromagnetic environment,which puts higher requirement forward to the performance and flexibility of receivers. Traditional analog receivers can't adapt the requirement because of bad performance and poor flexibility. With the development of digital technique, digital system can provide better performance. This makes that the research of digital receivers with good performance and strong flexibility becomes to be an important topic.Under the background of researching the digital receiver,this paper introduces the design theory and hardware realization of intermediate frequency (IF) sampling receivers. First,it introduces several structures, hardware requirements and present situation of digital receivers. Secondly, IF sampling digital receivers are discussed with several key technologies,such as analog—digital (AD) sampling technique, digital down converter (DDC) and digital low-pass filter and so on. Strict theory analysis and provement is present. Then the design parameters and system performance indexes of the digital receivers are analyzed. Finally,the method of designing digital receivers is discussed with GC1012B and software radio engineering, and the results and analysis of the digital receiver are given. Comparing with traditional analog receivers, this receiver has better performance, such as lower distortion, stronger flexibility and higher reliability and so on. It decreases change of gain and float of DC level,so it has wide application.