The proposed algorithm achieves a convergence performance close to that of the recently proposed, but substantially more complex improved proportionate MDF (IPMDF) algorithm.The popularity of voice over internet protocol (Vo IP) coupled with an increasing expectation for natural communication over packet-switched networks has called for improvement in Vo IP technologies in recent years.
We show how this can be achieved using two approaches and we compare their tradeoffs in terms of complexity and performance.
We next illustrate, in Section 3.2, how the sparseness of the Fourier transformed impulse response varies with the number of blocks in the MDF structure.
We illustrate two such approaches and discuss their tradeoff between convergence performance and computational complexity.
Simulation results show an improvement in convergence rate for the proposed algorithm over MDF and significantly reduced complexity.
For the majority of adapting iterations, under the sparse partial (SP) adaptation, only those taps corresponding to tap-inputs and filter coefficients both having large magnitudes are updated.
However, from time to time the algorithm gives equal opportunity for the coefficients with smaller magnitude to be updated by employing MMax tap-selection  offers an attractive means of achieving efficient implementation.
The PNLMS algorithm is then shown to outperform classical adaptive algorithms with a uniform step-size across all filter coefficients such as the normalized least-mean-square (NLMS) algorithm for NEC application .
Although the PNLMS algorithm achieves fast initial convergence, its rate of convergence reduces significantly.
As network systems migrate from traditional voice telephony over public switch telephone network (PSTN) to packet-switched networks for Vo IP, improving the quality of services (Qo S) for Vo IP has been and will remain a challenge , where the algorithmic delay is one of the significant factors for determining the budget for delay introduced by network echo cancellers.
The problem of network echo is introduced by the impedance mismatch between the 2- and 4-wire circuits of a network hybrid .
For effective network echo cancellation (NEC), adaptive filters such as shown in Figure have been employed for the estimation of network impulse response.