{"title":"Encoder-controller design for control over the binary-input Gaussian channel","authors":"Lei Bao, M. Skoglund","doi":"10.1109/ISSSTA.2010.5651343","DOIUrl":"https://doi.org/10.1109/ISSSTA.2010.5651343","url":null,"abstract":"In this paper, we consider the problem of the joint optimization of encoder-controller for closed-loop control with state feedback over a binary-input Gaussian channel (BGC). The objective is to minimize the expected linear quadratic cost over a finite horizon. This encoder-controller optimization problem is hard in general, mostly because of the curse of dimensionality. The result of this paper is a synthesis technique for a computationally feasible suboptimal controller which exploits both the soft and hard information of the channel outputs. The proposed controller is efficient in the sense that it embraces measurement quantization, error protection and control over a finite-input infinite-output noisy channel. How to effectively implement this controller is also addressed in the paper. In particular, this is done by using Hadamard techniques. Numerical experiments are carried out to verify the promising gain offered by the combined controller, in comparison to the hard-information-based controller.","PeriodicalId":433699,"journal":{"name":"2010 IEEE 11th International Symposium on Spread Spectrum Techniques and Applications","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128818623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Phase noise estimation and compensation for OFDM systems: A DCT-based approach","authors":"J. Bhatti, N. Noels, M. Moeneclaey","doi":"10.1109/ISSSTA.2010.5649866","DOIUrl":"https://doi.org/10.1109/ISSSTA.2010.5649866","url":null,"abstract":"We present an improved estimator of the phase noise θ(t) in OFDM systems, based on the approximation of the time-varying phasor exp(jθ(t)) by a discrete-cosine transform (DCT) basis expansion, containing only a few terms. Using pilot symbols, an initial least-squares estimate of the phase noise is obtained. The initial estimate is iteratively improved by also exploiting the soft decisions from the data symbols, obtained in a previous iteration. We demonstrate that the resulting (linearized) mean-square estimation error consists of two contributions: a contribution from the additive channel noise, that equals the modified Cramer-Rao lower bound when the soft decisions are assumed to equal the true data symbols, and a contribution that results from the phase noise modeling error. The modified Cramer-Rao lower bound is shown to be proportional to the number of estimated DCT coefficients. Performance can be optimized by a proper selection of the number of DCT coefficients in the expansion of the phasor. Iterative soft-decision-directed phase noise estimation yields a considerable performance improvement as compared to estimation using only pilot symbols. For an OFDM system with strong phase noise, the BER performance degradation resulting from the proposed scheme is limited to about 1 dB only.","PeriodicalId":433699,"journal":{"name":"2010 IEEE 11th International Symposium on Spread Spectrum Techniques and Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115283956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Study of signal propagations at 2.45GHz for wireless BAN applications","authors":"G. Sung, T. Aoyagi, K. Hamaguchi, R. Kohno","doi":"10.1109/ISSSTA.2010.5653579","DOIUrl":"https://doi.org/10.1109/ISSSTA.2010.5653579","url":null,"abstract":"WBAN signal propagations along human bodies were examined at 2.45GHz. By placing antennas on the human tissue equivalent phantom, the received signal strength was reduced by 10~15dB due to absorption. By deploying an electromagnetic (EM) shielding apron in close proximity of the antennas, the loss due to human body absorption could be compensated. Both the static measurement conducted in the laboratory environment and the in-situ measurement conducted with an individual in walking movement have suggested approaches to enhance WBAN signal propagations with the use of shielding materials. Utilizing shielding fabrics in WBANs for propagation enhancement has shown to be feasible, but an optimal deployment strategy needs to be developed.","PeriodicalId":433699,"journal":{"name":"2010 IEEE 11th International Symposium on Spread Spectrum Techniques and Applications","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122252071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}