Study, Design And Implementation Of Channelization Technology Based On Filterbanks For Shortwave Signals

This thesis focuses on a study, design and implementation of channelization technology for shortwave signals including DFT filerbanks suitable for constellation signals (MPSK/QAM), cosine modulated filterbanks suitable for MFSK signals along with the corresponding high-efficient algorithm based on DCT-IV, as well as wide range searching of shortwave signals etc. The work finished in this paper is a part of a large scale engineering project undertaken by the team the author works with.The main work and achievements of this paper are summarized as follows:1. The channelization technology based on DFT filterbanks with zero intermediate frequency is studied in depth, based on which a design and implementation targeting at wide range shortwave signals is completed. Simulation and test results have proved the validity and feasibility of the algorithm.2. A FPGA-besed design and implementation of DFT filterbanks with 128 channels is completed, where a time division FIR filter is proposed and employed that saves a lot of resources of the FPGA chip.3. The channelization technology based on cosine modulated filterbanks for real signals is studied in depth. The multiphase filtering structure of the algorithm based on DCT-IV is derived, and a high-efficient algorithm based on DCT-IV is provided. The spectrum reverse problem of odd channels of the cosine modulated filterbanks is also pointed out which must be taken care of while used in parallel receiving of MFSK signals. This kind of channelization technology is especially suitable for parallel receiving of mulichannel MFSK signals, thus has an important application prospect in the future.