DESIGN OF A SCALABLE AND RECONFIGURABLE DIGITAL FRONT- END WIDEBAND CHANNELIZER FOR SOFTWARE DEFINED RADIO

Abstract

The research work focused on the design of a digital front end channelizer useful in most software defined radios (SDRs) with the aim of exploiting the vast resources of digital signal processing which could be used in achieving portable, long lasting systems with extraordinary computational complexity software application that is capable of running at a lower power budget. Three channelization algorithms per-channel (PC), pipeline frequency transform (PFT) and polyphase fast Fourier transform (PFFT) uniform channelization algorithms were studied and designed for FM receivers using ‘Altera’ Digital Signal Processing (DSP) tool box in MATLAB/Simulink environment. The performance evaluation of the three algorithms was then carried out with the estimation of the multiplication per input samples of operation of the system, signal strength level or signal to noise ratio (SNR) and the computation time of each algorithm. The results show that the PFFT similar to PFT has the most efficient computational requirement with an overall multiplication per input samples of 22,000,000 mps (which is 24% less than the computation of PC) as a result of the polyphase multi-stage decimation technique. The simulation time shows that the PC runs at a more optimized processing time of (36 sec) as compared to PFT (7 min 10 sec) and PFFT (51 sec). Finally, the signal strength of the PFFT and the PC shows similar characteristics with range within 100- 110 dBm while that of PFT is within the range of 40- 90 dBm. Despite the evaluation results the PFFT out-performs the PC and PFT especially in terms of the silicon usage.