Research On MSK And LFM Transmission System In Same Bandwidth

With the development of science and technology, mankind has entered the era of information, communication exchanging between people with more needs. Digital communication has replaced analog communication and became an important mean of information transfer, resulting in a growing number of digital modulation step by step to replace the earlier analog modulation.Based on the developmental needs of communication,this paper proposed a MSK and LFM transmission system in same bandwidth, and analyzed the feasibility of the communication system by theory, then analyzed the performance of the communication system in detail through software simulation platform, at last the design scheme of hardware platform was given, simulating and testing each module to verify the performance of communication system.The main contents of this paper are as follows:Firstly, the characteristics and applications of MSK signals and LFM signals were analyzed, then introduced the methods of both MSK and LFM modulation and demodulation in detail, simulating them in Matlab software to compare with the theoretical value.Secondly, the concept, the property and the discrete algorithm on engineering of fractional Fourier transform (FrFT) were studied, the mathematical model of MSK and LFM transmission communication system in same bandwidth was given at the same time, then verified the feasibility of the algorithm through mathematical derivation, detailedly descripting the demodulation algorithm at receiver of the communication system, and analyzed its performance through software simulation.Thirdly, to verify the performance of MSK and LFM transmission communication system in same bandwidth, a hardware platform of MSK and LFM transmission communication system in same bandwidth which treated FPGA chip as the core processor part has been constructed, given the detailed scheme of hardware design.Eventually, programs of each module in both transmitter and receiver were compiled and debugged by using Verilog HDL designing language based on hardware platform, and the paper verified the MSK and LFM transmission communication system in same bandwidth feasibility and effectiveness from the perspective of hardware implementation, proving the practical application performance of MSK and LFM transmission communication system in same bandwidth.