MOAR: A Multi-Channel Opportunistic Auto-Rate Media Access Protocol for Ad Hoc Networks
BROADNETS '04 Proceedings of the First International Conference on Broadband Networks
Opportunistic spectral usage: bounds and a multi-band CSMA/CA protocol
IEEE/ACM Transactions on Networking (TON)
IEEE Transactions on Communications
Characterizing indoor wireless channels via ray tracing combined with stochastic modeling
IEEE Transactions on Wireless Communications
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Receive antenna selection for unitary space-time modulation over semi-correlated Ricean channels
IEEE Transactions on Communications
A novel ray tracing based multipath modeling approach for site-specific WLAN simulations
ICC'09 Proceedings of the 2009 IEEE international conference on Communications
Estimation over fading channels with limited feedback using distributed sensing
IEEE Transactions on Signal Processing
A MIMO channel model for wireless personal area networks
IEEE Transactions on Wireless Communications
EURASIP Journal on Wireless Communications and Networking
Wideband and ultrawideband channel models in working machine environment
Modelling and Simulation in Engineering - Special issue on Modeling and Simulation of Mobile Radio Channels
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In wireless communications, the relative strength of the direct and scattered components of the received signal, as expressed by the Ricean K factor, provides an indication of link quality. Accordingly, efficient and accurate methods for estimating K are of considerable interest. In this paper, we propose a general class of moment-based estimators which use the signal envelope. This class of estimators unifies many of the previous estimators, and introduces new ones. We derive, for the first time, the asymptotic variance (AsV) of these estimators and compare them with the Cramer-Rao bound (CRB). We then tackle the problem of estimating K from the in-phase and quadrature-phase (I/Q) components of the received signal and illustrate the improvement in performance as compared with the envelope-based estimators. We derive the CRBs for the I/Q data model, which, unlike the envelope CRB, is tractable for correlated samples. Furthermore, we introduce a novel estimator that relies on the I/Q components, and derive its AsV even when the channel samples are correlated. We corroborate our analytical findings by simulations.