If Digital Receiver Technology

With the technology of DSP, digital signal receiver has better performance, less signal distortion, more adaptability with environment and becomes appearing in various applications .During the work of the signal IF receiver, a project of this design is proposed in the thesis. On the basement of passband subsampling and digital downconvertion, according to QPSK with 30M carrier frequency and 8M bandwidth, digital IF channel is elaborately analyzed .In this module, multiple phase filters are elaborately designed .According to this module, IF digital signal is simulated . In the process of base band signal, according to correlative characteristics of PN codes, early-late gate base-band loop implements the tracking of PN codes. At the same time ,the receiver uses some algorithms in the estimation module of synchronization. With matlab, this thesis gets the range and precision of these algorithms. In the end ,software radio will be realized some day in the future.