Andreas Polydoros

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Abstract— Per-Survivor Processing (PSP) provides a general framework for the approximation of Maximum Likelihood Sequence Estimation (MLSE) algorithms whenever the presence of unknown quantities prevents the precise use of the classical Viterbi algorithm. This principle stems from the idea that data-aided estimation of unknown parameters may be embedded(More)
The simultaneous perturbation of an orthogonal frequency-division multiplexing receiver by phase noise plus a residual frequency offset (due to synchronization errors) is modeled here as a combined phase impairment, whose effect is evaluated analytically for the case of a frequency-selective fading channel. A nonpilot-aided (decision-directed) scheme is(More)
This paper deals with the analysis of the code-acquisition process performed by a mobile terminal in a code-division multiple-access cellular system. The fundamental contribution is the setting of a theoretical framework for code-acquisition analysis, accounting for the presence of fading and shadowing with specified coherence time. A multidwell(More)
AbsfnzcfWe derive and analyze optimal and suboptimal decision rules for the detection of constant-envelope quadrature digital modulations in broad-band noise. The effect of various stochastic models for the carrier phase is examined in detail, while no epoch or frequency uncertainty is assumed. The delay-and-multiply type of detector is also considered.(More)
In this paper we consider the joint sequence estimation, timing and phase recovery for linear modulation. The paper differs from the classical ones in the sense that time-diwrete algorithms suitable for fully digital receivers are discussed. Sufficient conditions are given such that the signal samples represent sufficient statistics. These conditions(More)
A simple circular state-diagram method has been recently proposed [2] for the modeling, analysis and optimization of straight serial search code acquisition in spread spectrum systems. Herein, the approach is generalized to arbitrary serial strategies, such as the Z-search, expanding window search etc. The basic idea is the construction of equivalent(More)