Computationally efficient algorithm for reducing the complexity of software radio receiver´s filter bank

This paper presents a computationally efficient method for extracting individual radio channels from the output of the wideband A/D converter. In a software radio, the extraction of individual channels from the output of the wideband A/D converter is by far the most computationally demanding task; hence it is very important to devise computationally efficient algorithms for this task. In this paper we proposed a new algorithm by assuming the symmetric signal with periods of the length-P (number of coefficients in low pass filter prototype) as an input signal to the subsampled filter bank that is derived from DFT filter bank. Also we divide the complex input x[n] into real and imaginary parts, then we perform operations in each part using two filter bank running in parallel. Finally we add outputs of two parts. With employing this algorithm to the subsampled filter bank channelizer, the complexity of filter bank channelizer was reduced by considerable amount of %81