Efficient clipping for broadband power line systems in impulsive noise environment

Abstract

For broadband power line communication systems, which may be incorporated with Orthogonal Frequency Division Multiplexing (OFDM) technique, the detrimental effect arising from strong and frequently occurred impulses is paramount as signaling on each subcarrier is simultaneously corrupted thanks to frequencydomain transformation on a per-OFDM symbol basis at the front-end receiver. In this perspective, channel coding epoch on the basis of per-OFDM symbol cannot effect the coding gain. Recently, clipping operation on received samples has been addressed as an effective approach to mitigate this incurring performance loss subject to impulsive noise, given the knowledge of the probability density function (PDF) of impulsive noise at receiver. In this paper, we forgo the a-priori knowledge of the PDF of impulsive noise but devise the threshold to clipping, only relying on the probability of occurrence of impulses. To attest our method, we conduct computer simulations in compliance with the IEEE 1901 standard over commonly adopted memoryless impulsive noise models. Promisingly, the proposed scheme is on par with its counterpart, where the threshold of a limiter is realized by assuming the PDF of impulsive channels perfectly known to receiver. In addition, the devised clipping scheme is shown to be robust against impulses of frequent occurrence characterized by excessively high energy in the signal-to-noise ratio range of interest, regardless of the impulsive noise model assumed.

Asynchronous impulsive noise mitigation in OFDM using adaptive threshold compressive sensing

“…After the support of impulsive noise is found, MMSE estimation can be adopted to construct the amplitude of impulsive noise from (5). A CS = S T F = [ψ 1 , ψ 2 , .…”

“…Because the impulsive noise in PLC environment is time variable, it is very hard to get the optimal threshold that minimizes the BER. Ef cient clipping scheme only relying on the probability of occurrence of impulsive noise is showed in [5]. However, it is not easy to predict the probability of occurrence of impulsive noise in the real PLC environment.…”

Robust turbo decoding in impulse noise channels

“…These facts provide the motivation for this study to address the impulse noise in a turbo-coded single-carrier system experiencing the very hostile environment, namely a high probability of occurrence of impulses characterized with a power greater than that of the background noise. Without resorting to the statistics of impulse noise, a limiter with a clipping threshold designed by Tseng et al [14], [15] in an OFDM system can effectively mitigate impulse. The turbo decoder there can also leverage the coding gain with the decoder metric adequately modified.…”

“…The turbo decoder there can also leverage the coding gain with the decoder metric adequately modified. Unlike [15], in which a limiter is invoked at the front-end receiver, the proposed design modifies the turbo decoder metric by directly incorporating the clipping concept into the trellis structure. In this approach, each received sample can be construed as a modulated symbol plagued by an additive memoryless clipping noise, of which the probability density function (PDF) can be easily identified even in the absence of impulse statistics.…”

Deep Clipping for Impulsive Noise Mitigation in OFDM-Based Power-Line Communications

“…The simplest and most efficient method for mitigating impulsive noise in OFDM-based PLC systems is nonlinear preprocessors at the receiver [1]. Three nonlinear preprocessors have been discussed and analyzed in [9] and [10].…”