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When is uncoded transmission optimal? This paper derives easy-to-check necessary and sufficient conditions that do not require finding the rate-distortion and the capacity-cost functions. We consider the symbol-by-symbol communication of discrete-time memo ...
We design low-density parity-check (LDPC) codes that perform at rates extremely close to the Shannon capacity. The codes are built from highly irregular bipartite graphs with carefully chosen degree patterns on both sides. Our theoretical analysis of the c ...
We show how a multiuser chaos-based communication system can be designed. The approach builds on the recently introduced method of ergodic chaos shift keying. This method uses a nonlinear correlation estimator for extracting the binary information from the ...
Pulse amplitude modulation scheme with the same spectral efficiency as QAM, that is twice the spectral efficiency of conventional PAM schemes, comprising the steps of: (1) forming a train of pulses q(t -kT/2) = p(t - k T/2)cos2 pi fo(t- k T/2), wherein p(t ...
This paper presents a new and simple compact model for the intrinsic metal oxide semiconductor (MOS) transistor, which accurately takes into account the non quasistatic (NQS) effects. This is done without any additional assumption or simplification than th ...
We investigate the use of multi-antennas at both ends of a point-to-point communication system over the additive Gaussian channel. We consider a system with t transmit antennas and r receive antennas in which the received vector v∈Cτ depends on the transmi ...
Linear transforms and expansions are fundamental mathematical tools of signal processing. In particular, the wavelet transform has played an important role in several signal processing tasks, compression being a prime example. A signal can be represented i ...
We construct new families of error-correcting codes based on Gallager's (1973) low-density parity-check codes. We improve on Gallager's results by introducing irregular parity-check matrices and a new rigorous analysis of hard-decision decoding of these co ...
This paper addresses the problem of training sequence design for multiple-antenna transmissions over quasi-static frequency-selective channels. As performance metric for channel estimation, mean square error is adopted. To achieve the minimum mean square e ...
The master-slave synchronization of two chaotic systems that interact over a noisy channel is analyzed from an information theoretic point of view. It is argued that arbitrarily precise synchronization, in the sense of the mean square synchronization error ...
