TY - JOUR
T1 - Practical issues in estimation over multiaccess fading channels with TBMA wireless sensor networks
AU - Gao, Ping
AU - Tepedelenlioglu, Cihan
N1 - Funding Information:
Manuscript received November 14, 2006; revised July 12, 2007. The associate editor coordinating the review of this manuscript and approving it for publication was Dr. Zhi Tian. This work was supported by the NSF under CAREER Grant CCR-0133841. Parts of this work were presented at Proc. IEEE ICC ’06 Istanbul, Turkey, June 2006, and Proc. IEEE Globecom ’06, San Francisco, CA, Nov./Dec. 2006.
PY - 2008/3
Y1 - 2008/3
N2 - Practical issues in histogram and parameter estimation over fading channels with type-based multiple access (TBMA) sensor networks is addressed in this paper, where the parameter of interest is estimated through the histogram, or type, of the observations. Existing histogram estimators in the literature require the transmitted signal waveforms to be orthogonal to represent different observations. If the fading channels from the sensors to the fusion center are zero mean, channel state information (CSI) is required at the sensor side. However, in practice, the interference between the orthogonal waveforms, and channel estimation error (CEE) cannot be avoided. How these practical issues affect the histogram and parameter estimation is discussed in this paper. A unified framework for histogram and parameter estimation in the presence of interference and imperfect CSI is proposed. In the interference-free case, a novel histogram estimator is proposed, which does not require the knowledge of the channel statistics at the fusion center, and yields an asymptotically optimal estimator. This approach is then generalized to the presence of interference. The existing estimators without the knowledge of interference statistics are shown to be biased, which motivates the proposed asymptotically optimal estimators that utilize interference statistics. Moreover, the performance of the asymptotically optimal estimators are shown to deteriorate when the waveforms are not orthogonal. Simulation results corroborate our analysis.
AB - Practical issues in histogram and parameter estimation over fading channels with type-based multiple access (TBMA) sensor networks is addressed in this paper, where the parameter of interest is estimated through the histogram, or type, of the observations. Existing histogram estimators in the literature require the transmitted signal waveforms to be orthogonal to represent different observations. If the fading channels from the sensors to the fusion center are zero mean, channel state information (CSI) is required at the sensor side. However, in practice, the interference between the orthogonal waveforms, and channel estimation error (CEE) cannot be avoided. How these practical issues affect the histogram and parameter estimation is discussed in this paper. A unified framework for histogram and parameter estimation in the presence of interference and imperfect CSI is proposed. In the interference-free case, a novel histogram estimator is proposed, which does not require the knowledge of the channel statistics at the fusion center, and yields an asymptotically optimal estimator. This approach is then generalized to the presence of interference. The existing estimators without the knowledge of interference statistics are shown to be biased, which motivates the proposed asymptotically optimal estimators that utilize interference statistics. Moreover, the performance of the asymptotically optimal estimators are shown to deteriorate when the waveforms are not orthogonal. Simulation results corroborate our analysis.
KW - Fading channels
KW - Parameter estimation
KW - Sensor networks
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U2 - 10.1109/TSP.2007.909000
DO - 10.1109/TSP.2007.909000
M3 - Article
AN - SCOPUS:40749083542
SN - 1053-587X
VL - 56
SP - 1217
EP - 1229
JO - IEEE Transactions on Signal Processing
JF - IEEE Transactions on Signal Processing
IS - 3
ER -