DESIGN AND IMPLEMENTATION OF SOFTWARE DEFINED RADIO SYSTEM ON FPGA FOR MEDICAL SIGNALS

Abstract

The fourth generation of wireless communications will demand the use of software radio technology as the basic architecture to support multi-standard and multi-mode radio designs. The aim of this thesis is to design and implement a baseband section of software defined radio based wireless communication system for transmission of medical signals, which requires multi communication links. Software defined radio is a feasible solution for reconfigurable radios, which can perform different functions at different times on the same hardware. The baseband section of a wireless communication system is first simulated and then implemented in hardware. Baseband processing of medical signals involves functions such as forward error correction, modulation and digital up conversion on transmitter side and digital down conversion, demodulation and viterbi decoding on receiver side. System involving all these functions is developed. Digital Up/Down conversion is present in intermediate frequency section of Software defined radio. The performance of the baseband transmitter is analyzed using constellation and eye diagrams for different modulation techniques i.e QPSK, QAM techniques and different signal-to-noise ratios, while considering an additive white Gaussian noise channel. The performance of the receiver is analyzed by comparing the input and output waveforms by transmitting EEG and EMG signals. The performance of the system in is also analyzed by implementing the system in hardware using Xilinx Spartan 3E field programmable gate array. A comparison of the simulation results with the results obtained from 0 implementing the system on Spartan 3E hardware is presented and discussed. It is shown that the simulation results and experimental results are similar