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The probability of incorrect beam selection (PIBS) with a switched multibeam antenna system is theoretically analyzed under power-limited and interference-limited mobile communication environments. Periodic transmission of unique word sequence followed by information symbol sequence is assumed. The model of beam selection used in this paper is based upon a simple three-stage mechanism: 1) signal validation; 2) averaging; and 3) selection of the largest output. Complex correlation peaks corresponding to the unique words, detected by the matched filter for the signal validation, are averaged over several consecutive unique words, and a beam having the largest output is selected. Equally weighted noncoherent integration is assumed for the averaging process. The beam selection takes place frame-by-frame. The first half of this paper is devoted to the PIBS derivation for a simple switched two-beam antenna system. Numerical calculation results are then presented. The latter half of this paper investigates the impact of the incorrect beam selection on overall average signal-to-noise (SNR) power ratio and signal-to-interference (SIR) power ratio. The amount of the overall SNR (or SIR) improvement over the omnidirectional antenna depends on the propagation conditions. In general, larger improvements can be achieved by smaller values of PIBS. Index Terms - Digital cellular system, switched multibeam antenna, TDMA, time diversity, unique word detection.

In this paper, we introduce a way to approximate meromorphic functions belonging to Poincaré's ‘new’ class by rational functions. The class consists of meromorphic functions having a ‘théorèm de multiplication’ with a suitable condition, which is a system of difference equations on the transform sendingto, where. Since graphing rational functions is somewhat easy, we are able to know rough graphs of those ‘new’ functions by our result. Our method uses repeated substitutions of the difference equations. [ABSTRACT FROM AUTHOR]

The aim of this paper is to note that properties of being elementary in differential and difference senses are different as a whole. In this paper, we introduce the notion of finitelyn-reducible difference field extensions and study the irreducibility of algebraic difference equations of order 1. As a result, we find that the exponential functionand the Weierstrass functioncannot be built up by using the variablezand constants, together with repeated algebraic operations and the taking of solutions of linear difference equations on the multiplicationand solutions of such algebraic difference equations as difference Riccati equations on. [ABSTRACT FROM PUBLISHER]

In this paper we will study the irreducibility of q- , q-Painlevé equation of type , in the sense of order using the notion of decomposable extensions. q- is one of the special non-linear q-difference equations of order 2 with symmetry and is also called q- . [ABSTRACT FROM AUTHOR]