A Low Complexity Reconfigurable IFIR Filter for Software Defined Radio Channelizers

Reconfigurable digital filters with low hardware complexity are essential requirements in today's mobile technology, where the latest trend is to support multi-standard communication systems on the same device. In software defined radios (SDR), the bandwidths are to be allocated intelligently such that the spectrum utilization is efficient. SDR uses digital channelizers to extract multiple channels from a wideband signal. Here, sharp filters are required for minimum spectral efficiency and to have minimum interference from adjacent channels.The frequency response masking (FRM) technique has been proved to result in sharp digital filters with low complexity. However, FRM filters cannot be easily designed for very narrow bandwidth filters, which are required to realize most of the wireless standards. In this paper, we propose reconfigurable interpolated finite impulse response (IFIR) filters using Farrow structure, to realize the various wireless communication standards. A novel approach is proposed for the design of the filters in the IFIR structure, which results in lower hardware complexity reconfigurable structures, when compared to all the existing structures.