An Adaptive Time Delay Alignment Technique Based on Equalizer Taps in a Sensor Array

Abstract:

In the wireless sensor network, every node is energy and resource limited and the received signal is weak, which requires less complexity and low computation signal combination algorithm to improve the signal-to-noise ratio (SNR) of the combined output signal. Considering the computation and time-varying delay, this paper proposes an adaptive feedback time-delay alignment method based on equalizer taps to decrease the SNR loss caused by time-delay difference. The relationship between the equalizer taps and time-delay difference is derived according to the Nyquist first criterion and the gradient descent algorithm is adopted to iteratively adjust the time delay of one antenna signal. The numerical results show that the algorithm can almost eliminate the time difference and the SNR loss decreases. The bit error rate (BER) performance is obviously improved.

• Periodical: Applied Mechanics and Materials (Volume 551)
• Pages: 448-453
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.551.448
• Online since: May 2014
• Authors: Qi Hui Tu*, Cai Yao Shen, Hong Yi Yu, Yun Peng Hu
• Keywords: Adaptive Time Delay Alignment, Equalizer Taps, Feedback, Signal Combination

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