Madan Kumar Lakshmanan

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Spectrum Sensing is an important functionality of Cognitive Radio (CR). Accuracy and speed of estimation are the key indicators to select the appropriate spectrum sensing technique. Conventional spectrum estimation techniques which are based on Short Time Fourier Transform (STFT) suffer from familiar problems such as low frequency resolution, high variance(More)
In this article, we investigate the application of wavelet packet transform as a novel spectrum sensing approach. The main attraction for wavelet packets is the tradeoffs they offer in terms of satisfying various performance metrics such as frequency resolution, variance of the estimated power spectral density (PSD) and complexity. The results of the(More)
This article presents a cognitive radio system built from a wavelet packet multi-carrier modulation MIMO scheme with a VBLAST receiver architecture. The objective is to combine the promise of optimum utilization of radio resources by cognitive radio, the high data throughput without additional bandwidth/power requirements offered by MIMO and the flexibility(More)
Abstract— Wavelet Packet based Multi-Carrier Modulation (WPMCM) is an efficient transmission technique which has the advantage of being a generic scheme whose characteristics can be customized to fulfill a design specification. However, WPMCM is sensitive and vulnerable to time synchronization errors because its symbols overlap. In this paper, we design new(More)