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Annual Conference on Information Sciences and Systems (CISS)

作者： C. Sinan Güntürk Mark Lammers Alex Powell Rayan Saab Özgür Yilmaz Courant Institute of Mathematical Sciences New York University NY USA North Carolina State University Wilmington NC USA Vanderbilt University Nashville TN USA University of British Columbia Vancouver BC Canada

Sobolev dual frames have recently been proposed as optimal alternative reconstruction operators that are specifically tailored for Sigma-Delta (¿¿) quantization of frame coefficients. While the canonical dual frame of a given analysis (sampling) frame is optimal for the white-noise type quantization error of Pulse Code modulation (PCM), the Sobolev dual offers significant reduction of the reconstruction error for the colored-noise of ¿¿ quantization. However, initial quantitative results concerning the use of Sobolev dual frames required certain regularity assumptions on the given analysis frame in order to deduce improvements of performance on reconstruction that are similar to those achieved in the standard setting of bandlimited functions. In this paper, we show that these regularity assumptions can be lifted for (Gaussian) random frames with high probability on the choice of the analysis frame. Our results are immediately applicable in the traditional oversampled (coarse) quantization scenario, but also extend to compressive sampling of sparse signals.

关键词： Quantization Sampling methods Delta-sigma modulation Pulse modulation Noise shaping Low pass filters modulation coding Phase change materials Colored noise Performance analysis

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Novel Efficient Algorithms for Symmetric Constellation Subset Selection

Novel Efficient Algorithms for Symmetric Constellation Subse...

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IEEE International Conference on Communications (ICC)

作者： S.-H. Huang H.-C. Wu S. Y. Chang Computer Science Department City University of Hong Kong Hong Kong China Department of Electrical and Computer Engineering Louisiana State University Baton Rouge LA USA Department of Computer Science National Tsing Hua University Taiwan

Adaptive modulation communication systems have been popular nowadays. The tradeoff between the symbol error rate and the data rate resulting from the constellation option is crucial in adaptive modulation. In this paper, we propose a constellation subset selection (CSS) approach to seek this tradeoff and design novel efficient approximation algorithms to tackle the CSS problems. The new theorems and studies on the algorithmic and systematic aspects for the constellation subset selection are facilitated. Our attempt to cope with the CSS problems would be valuable for the future communication systems with adjustable constellation sets.

关键词： Algorithm design and analysis Approximation algorithms Communication systems Error analysis Control Systems Society Adaptive systems Constellation diagram Quality of service Quadrature amplitude modulation modulation coding

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A Simplified Soft Decision Demapping Algorithm of 16-APSK Signals in AWGN Channels

A Simplified Soft Decision Demapping Algorithm of 16-APSK Si...

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International Conference on Networks Security, Wireless Communications and Trusted Computing, NSWCTC

作者： Enxin Yao Shuai Yang Wei Jiang School of Electronic Engineering and Computer Science Peking University China

ISBN: (纸本)9781424465972;9780769540115

This paper proposes a novel soft decision demapping algorithm of 16-Amplitude Phase Shift Keying (16-APSK) signals in AWGN channels. The proposed algorithm has a lower complexity compared with the well-known Log-Max algorithm. Numerical results show that the proposed algorithm degrades little in BER performance when it is implemented with Low Density Parity Check (LDPC) codes.

关键词： AWGN channels Parity check codes Digital video broadcasting Bit error rate Computational complexity Phase shift keying Degradation Decoding modulation coding Computational modeling

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A joint AMC-ARQ design in MIMO-OFDM systems based on channel matrix singular value decomposition at the physical layer

A joint AMC-ARQ design in MIMO-OFDM systems based on channel...

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IEEE International Conference on Ubi-Media Computing

作者： Chang Li Xu Meng College of physics and electronic information engineering WenZhou University WenZhou China

In this paper, we developed a joint AMC-ARQ design combining adaptive modulation and coding at the physical layer with automatic repeat request protocol at the data link layer in multiple-input multiple-output(MIMO) orthogonal frequency division multiplexing(OFDM) systems which is converted into a series of parallel and independent flat sub-channels based on channel matrix singular value decomposition(SVD) at the physical layer. Theoretical derivation supports that our proposed design maximizes the spectral efficiency under prescribed delay and error performance constrains. Simulation results show that this cross-layer design based on channel matrix singular decomposition for MIMO-OFDM obtains more than 2 dB gain in spectral efficiency comparing the traditional SISO cross-layer design.

关键词： Matrix decomposition Singular value decomposition Physical layer Matrix converters Cross layer design modulation coding Automatic repeat request Protocols Frequency division multiplexing Delay

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A New Constellation Mapping Scheme of MPSK in BICM-ID

A New Constellation Mapping Scheme of MPSK in BICM-ID

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International Conference on Networks Security, Wireless Communications and Trusted Computing, NSWCTC

作者： Changyou Guo Dezhou University Dezhou China

ISBN: (纸本)9781424465972;9780769540115

With the rapidly development of beyond third generation mobile communication system, how to improve the spectrum efficiency becomes a key problem. Based on the analysis of the quality of iterative decoding influenced by constellation labeling, a new general mapping rules was proposed in bit interleaved coded modulation and iterative decoding. On the one hand, to improve the performance of the system at higher signal noise ratio, the new scheme was designed of maximum squared Euclidean distance between the symbols which Hamming distance is one. On the other hand, to improve the soft-output information quality of demodulator, the new scheme has better squared Euclidean distance spectrum when Hamming distances is more than one, so the performance was improved at lower signal noise ratio. Simulation results and performance analysis show that the proposed scheme can improve the performance of BICM-ID at lower SNR under AWGN and Rayleigh fading channels.

关键词： Signal to noise ratio Iterative decoding Additive white noise Gaussian noise Euclidean distance 3G mobile communication Labeling Interleaved codes modulation coding Signal design

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Turbo decoder design for advanced T-DMB baseband receiver SoC

Turbo decoder design for advanced T-DMB baseband receiver So...

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IEEE International Conference on Consumer Electronics (ICCE)

作者： Hyuk Kim Juehyun Lee Jinkyu Kim Duckwhan Kim Bon-tae Koo Electronics and Telecommunications Research Institute Daejeon South Korea

ISBN: (纸本)9781424443147;9781424443161

This paper presents a design of a turbo decoder for advanced terrestrial DMB(AT-DMB) baseband receiver SoC. The turbo decoder uses the max-log-map algorithm with simple min function. It features an interleaver address generator that computes the interleaved addresses for four block sizes enabling it to quickly switch context to support different data services. The decoder is integrated to the AT-DMB baseband receiver SoC with other functional blocks. The AT-DMB baseband receiver SoC is fabricated using 0.13 um 1 poly 8 metal technology.

关键词： Decoding Baseband Turbo codes Digital multimedia broadcasting Multimedia communication modulation coding Switches Bandwidth Video coding Convolutional codes

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Rate Adaptation Games in Wireless LANs: Nash Equilibrium and Price of Anarchy

Rate Adaptation Games in Wireless LANs: Nash Equilibrium and...

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2010 Proceedings IEEE INFOCOM

作者： Prasanna Chaporkar Alexandre Proutiere Bozidar Radunovic Indian Inst. of Technology Bombay India Microsoft Research Cambridge UK

ISBN: (纸本)9781424458363

In Wireless LANs, users may adapt their transmission rates depending on the radio conditions of their links so as to maximize their throughput. Recently, there has been a significant research effort in developing distributed rate adaptation schemes. Unlike previous works that mainly focus on channel tracking, this paper characterizes the optimal reaction of a rate adaptation protocol to the contention information received from the MAC. We formulate this problem analytically. We study both competitive and cooperative user behaviors. In the case of competition, users selfishly adapt their rates so as to maximize their own throughput, whereas in the case of cooperation they adapt their rates so as to maximize the overall system throughput. We show that the Nash Equilibrium reached in the case of competition is inefficient (i.e. the price of anarchy goes to infinity as the number of users increases), and provide insightful properties of the socially optimal rate adaptation schemes. We find that recently proposed collision-aware rate adaptation algorithms decrease the price of anarchy. We also propose a novel collision-aware rate adaptation algorithm that further reduces the price of anarchy.

关键词： Wireless LAN Nash equilibrium Throughput Communications Society Media Access Protocol H infinity control Time factors Hardware modulation coding Propagation losses

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Linear Power and Efficiency at Microwave and Millimeter-Wave Using TWTA-Based Microwave Power Modules

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IEEE MICROWAVE MAGAZINE 2009年第7期10卷 78-89页

作者： Katz, Allen Gray, Robert Dorval, Roger Coll New Jersey Elect & Comp Engn Dept Ewing NJ USA Linearizer Technol Inc Hamilton NJ 08619 USA

The results in this article clearly indicate the importance of millimeter-wave power module (MPM) technology and illustrate the enormous value of combining an MPM with a linearizer. This combination makes linearized MPMs highly attractive for commercial and government communications applications. A linearized-MPM can provide significantly higher power and efficiency for a comparable linearity in a lighter weight and more compact package than alternate options. The linearizer allows an MPM to provide four times the output power for many linear applications, and more than a 10 dB improvement in two-carrier linearity over much of its power range. For currently available MPMs, linearization allows operation with common digital modulations with a spectral regrowth of greater than 30 dB at an output power of 50 W with an overall efficiency of 25%. Even greater benefits are provided for complex digitally modulated signals as wideband code division multiple access (WCDMA). This MPM can be housed in an 820 cubic cm volume, 2.3 kg in weight and allows operation over multi-octave bandwidths.

关键词： Multichip modules Millimeter wave technology Linearity Power generation Digital modulation Multiaccess communication Government Microwave communication Packaging modulation coding

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Reduced complexity detection technique for layered space time block coded multiple-input multiple-output orthogonal frequency division multiplexing

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IET COMMUNICATIONS 2009年第1期3卷 115-122页

作者： Yousafzai, A. K. Nakhai, M. R. Center for Telecommunications Research King's College London Strand Westminster WC2R 2LS UK

The combination of vertical Bell Labs layered space time (V-BLAST) and space time block coding (STBC), known as a Layered STBC (LSTBC) system, offers high spectral efficiency with a higher order of diversity. The system structure, computational complexity and error performance of the V-BLAST and LSTBC multiple-input multiple-output orthogonal frequency division multiplexing systems are analysed and compared. It is shown that, compared with V-BLAST, the overall diversity order of LSTBC increases two fold. This diversity gain is achieved at the expense of a four-fold increase in the computational complexity of the QR decomposition (QRD) algorithm, required at the receiver of both LSTBC and V-BLAST. The authors propose a modified QRD algorithm which reduces this four-fold complexity to two fold.

关键词： diversity reception QR decomposition algorithm diversity gain diversity order block codes space-time codes error performance OFDM modulation layered space time block coded MIMO OFDM system vertical Bell Labs layered space time complexity detection technique multiple-input multiple-output orthogonal frequency division multiplexing V-BLAST computational complexity modulation coding MIMO communication

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Concatenated bit-interleaved coded modulation and orthogonal space-time block codes over fading channels

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IET COMMUNICATIONS 2009年第8期3卷 1354-1362页

作者： Teimouri, M. Hedayat, A. Shiva, M. Univ Tehran Sch Elect & Comp Engn Ctr Excellence Appl Electromagnet Syst Tehran 14399 Iran Navini Networks Richardson TX 75082 USA

The authors analyse concatenated bit-interleaved coded modulation and orthogonal space-time block codes (OSTBC) over fading channels in the absence and presence of channel state information (CSI) in receiver. The authors derive analytical expressions for bit and frame error probabilities based on which corresponding designing rules are proposed. The analytical results are for arbitrary rate of constituent STBC and arbitrary convolutional code, and for CSI-aware receiver is for any number of transmit and receive antennas. Simulation results are presented to confirm the validity of the proposed designing rules. Moreover, the simulation results show that the proposed system outperforms concatenated trellis coded modulation and OSTBC.

关键词： TRANSMITTING Orthogonal Simulation results trellis coded modulation Fading channels Block codes modulation coding Bit interleaved coded modulation

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