Vlsi Implementation Ofdlms Adaptive Algorithm to Analyze Critical Path

This paper presents a precise analysis of the criticalpath of the least mean square ( LMS) adaptive filter for deriving itsarchitectures for high speed and lowcomplexityimplementation.It is shown that the direct-form LMS adaptive filter has nearly thesame critical path as its transpose-form counterpart, but providesmuch faster convergence and lower register complexity. From thecritical-path evaluation, it is further shown that no pipelining isrequired for implementing a direct-form LMS adaptive filter formost practical cases, and can be realized with a very small adaptation delay in cases where a very high sampling rate is required.Based on these findings, this paper proposes three structures of theLMS adaptive filter: (i) Design 1 having no adaptation delays, (ii)Design 2 with only one adaptation delay, and (iii) Design 3 withtwo adaptation delays. For comparison of proposed systems its Verilog coded and synthesized in Xilinx.