Alfonso Martinez

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This correspondence presents a simple method to accurately compute the error probability of bit-interleaved coded modulation (BICM). Thanks to the binary-input output-symmetric (BIOS) nature of the channel, the pairwise error probability (PEP) is equal to the tail probability of a sum of random variables with a particular distribution. This probability is(More)
We revisit the information-theoretic analysis of bit-interleaved coded modulation (BICM) by modeling the BICM decoder as a mismatched decoder. The mismatched decoding model is well defined for finite, yet arbitrary, block lengths, and naturally captures the channel memory among the bits belonging to the same symbol. We give two independent proofs of the(More)
The wideband regime of bit-interleaved coded modulation (BICM) in Gaussian channels is studied. The Taylor expansion of the coded modulation capacity for generic signal constellations at low signal-to-noise ratio (SNR) is derived and used to determine the corresponding expansion for the BICM capacity. Simple formulas for the minimum energy per bit and the(More)
This paper determines the range of feasible values of standard error exponents for binary-input memoryless symmetric channels of fixed capacity <i>C</i> and shows that extremes are attained by the binary symmetric and the binary erasure channel. The proof technique also provides analogous extremes for other quantities related to Gallager's(More)
We show that Gallager's random coding error exponent of an arbitrary binary-input memoryless symmetric channel is upper-bounded by that of the binary erasure channel and lower-bounded by that of the binary-symmetric channel of the same capacity. We apply the result to find the extremes of the channel dispersion for the aforementioned class of channels.
This paper investigates the performance of M -ary Amplitude-Phase Shift Keying (APSK) digital modulation over typical nonlinear satellite channels. The effect of the satellite nonlinearity is studied, and distortion preand post-compensation techniques for coded APSK are presented. Moreover, clock timing, signal amplitude and carrier phase recovery schemes(More)
The spectral efficiency (channel capacity) of the optical direct-detection channel is studied. The modeling of the optical direct-detection channel as a discrete-time Poisson channel is reviewed. Closed-form integral representations for the entropy of random variables with Poisson and negative binomial distributions are derived. The spectral efficiency(More)
This paper presents a simple and very accurate method to evaluate the error probability of bit-interleaved coded modulation. Modelling the channel as a binaryinput continuous-output channel with a non-Gaussian transition density allows for the application of standard bounding techniques for Gaussian channels. The pairwise error probability is equal to the(More)
This paper considers the problem of channel coding with a given (possibly suboptimal) maximum-metric decoding rule. A cost-constrained random-coding ensemble with multiple auxiliary costs is introduced, and is shown to achieve error exponents and second-order coding rates matching those of constant-composition random coding, while being directly applicable(More)