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Codebook

About: Codebook is a research topic. Over the lifetime, 8492 publications have been published within this topic receiving 115995 citations.


Papers
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Journal ArticleDOI
TL;DR: In this article, a generalized partly orthogonal designs (PODs) was proposed, where both high-rate and low-rate feedback information with possible feedback errors were incorporated.
Abstract: The goal of combining beamforming and spacetime coding is to obtain full-diversity order and to provide additional received power (array gain) compared to conventional space-time codes. In this work, a class of code constellations is proposed, called generalized partly orthogonal designs (PODs) and both high-rate and low-rate feedback information is incorporated with possible feedback errors. A binary symmetric channel (BSC) model characterizes feedback errors. Two cases are studied: first, when the BSC bit error probability is known a priori to the transmission ends, and second, when it is not known exactly. Based on a minimum pairwise error probability (PEP) design criterion, we design a channel optimized vector quantizer (COVQ) for feedback information and a precoder matrix codebook to adjust the transmission codewords. The attractive property of our combining scheme is that it converges to conventional space-time coding with low-rate and erroneous feedback and to directional beamforming with high-rate and error-free feedback. This scheme also shows desirable robustness against feedback channel modeling mismatch.

32 citations

Journal ArticleDOI
TL;DR: A minimax criterion of minimizing the maximum partial distortion is introduced in this paper, and a new algorithm called minimax partial distortion competitive learning (MMPDCL) is developed for optimal codebook design.
Abstract: The design of the optimal codebook for a given codebook size and input source is a challenging puzzle that remains to be solved. The key problem in optimal codebook design is how to construct a set of codevectors efficiently to minimize the average distortion. A minimax criterion of minimizing the maximum partial distortion is introduced in this paper. Based on the partial distortion theorem, it is shown that minimizing the maximum partial distortion and minimizing the average distortion will asymptotically have the same optimal solution corresponding to equal and minimal partial distortion. Motivated by the result, we incorporate the alternative minimax criterion into the on-line learning mechanism, and develop a new algorithm called minimax partial distortion competitive learning (MMPDCL) for optimal codebook design. A computation acceleration scheme for the MMPDCL algorithm is implemented using the partial distance search technique, thus significantly increasing its computational efficiency. Extensive experiments have demonstrated that compared with some well-known codebook design algorithms, the MMPDCL algorithm consistently produces the best codebooks with the smallest average distortions. As the codebook size increases, the performance gain becomes more significant using the MMPDCL algorithm. The robustness and computational efficiency of this new algorithm further highlight its advantages.

32 citations

Journal ArticleDOI
TL;DR: In this article, the authors introduced a new measure of information-theoretic secrecy based on rate-distortion theory and studied it in the context of the Shannon cipher system, and characterized the optimal tradeoff of secret key rate, list rate, and eavesdropper distortion.
Abstract: We introduce a new measure of information-theoretic secrecy based on rate-distortion theory and study it in the context of the Shannon cipher system. Whereas rate-distortion theory is traditionally concerned with a single reconstruction sequence, in this paper, we suppose that an eavesdropper produces a list of $2^{nR_{\sf L}}$ reconstruction sequences and measure secrecy by the minimum distortion over the entire list. We show that this setting is equivalent to one in which an eavesdropper must reconstruct a single sequence, but also receives side information about the source sequence and public message from a rate-limited henchman (a helper for an adversary). We characterize the optimal tradeoff of secret key rate, list rate, and eavesdropper distortion. The solution hinges on a problem of independent interest: lossy compression of a codeword uniformly drawn from a random codebook. We also characterize the solution to the lossy communication version of the problem in which distortion is allowed at the legitimate receiver. The analysis in both the settings is greatly aided by a recent technique for proving source coding results with the use of a likelihood encoder.

32 citations

Journal Article
TL;DR: In this paper there is enclosed a desription of vector quantisation idea, the design techniques, optimization methods and practical implementations, as well as practical implementations of these techniques and methods.
Abstract: In the last few years Vector Quantisation has become an important technique in speech and image compression and recognition. The jump from one dimension to the multiple ones allows wealth of new ideas, concepts, techniques and applications. In this paper there is enclosed a desription of vector quantisation idea, the design techniques, optimization methods and practical implementations.

32 citations

Patent
01 Jul 2011
TL;DR: In this paper, a transmission method and apparatus using a codebook from that of a wireless communication system, more specifically to multi-antenna enabled wireless communication systems, is presented.
Abstract: The present invention is a transmission method and apparatus using a codebook from that of a wireless communication system, more specifically to multi-antenna enabled wireless communication system. A method of transmitting a downlink signal at a base station in accordance with one embodiment of the present invention includes the steps of receiving a first and a second precoding matrix indicator (PMI) from the terminal; A second matrix from the first PMI determining a first matrix (W1) from the first codebook comprising precoding matrix indication and the second codebook comprising precoding matrix to the second PMI is indicated (W2) determining, the step of determining a precoding matrix (W) based on the first matrix (W1) and a second matrix (W2); Performing precoding by using the determined precoding matrix (W) in one or more layers in which the downlink signal is mapped; And each of a precoding matrix contained in the first codebook, and transmitting the precoded signals to the mobile station is composed of a block diagonal matrix (block diagonal matrix), one block and one block of the comparison may be in the form became predetermined phase value is multiplied.

32 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023217
2022495
2021237
2020383
2019432
2018364