Research And Design Of Multi-band Signal Receiver In Software Defined Radio

Software radio is a new technology being developed in the 21 st century.Software radio allows the same device to support multiple standards and methods.In software radio receiver technology,sampling is one of the key technologies.Bandpass sampling method is a commonly used sampling method in software defined radio.However,the limitation of bandpass sampling is that signal aliasing often occurs after sampling.The traditional method is to avoid aliasing.Therefore,there are many restrictions on sampling frequency selection.And solve the problem of signal aliasing in software radio receivers.This paper first introduces the basic knowledge of software radio and bandpass sampling,and lays a theoretical foundation for the design of multi-band receivers based on software defined radio.Secondly,the paper designs and analyzes the anti-aliasing processing method for different aliased signals.Based on the second-order bandpass sampling model,the corresponding algorithm is designed to achieve signal separation.The three signal aliasing cases are processed by the third-order sampling model;the filter is improved for the image aliasing problem and the gain model is used to realize the aliasing processing of the signal itself;and the signal can be solved in the paper.In the case of aliasing,the traditional sampling frequency selection rule is improved,which simplifies the sampling frequency selection process.Finally,the performance of the designed receiver is analyzed by simulation and the influence of related parameters is analyzed.The software radio receiver designed in this paper can be used for multi-signal reception,which improves the flexibility of software defined radio.