Sequential PN Acquisition Scheme Based on a Fuzzy Logic Controller

Fuzzy Logic Control for Multiresolutive Adaptive PN Acquisition Scheme in Time-Varying Multipath Ionospheric Channel

“…Research work in the field of fuzzy logics applied to the estimation of the above mentioned channel was first applied in (Alsina et al, 2005a) for serial search acquisition systems in AWGN channels, afterwards applied to the same channel but in the multiresolutive structure (Alsina et al, 2009a;Morán et al, 2001) in papers (Alsina et al, 2007b;2009b) achieving good results. In this chapter the application of fuzzy logic control trained for Rayleigh fading channels (Proakis, 1995) with Direct-Sequence Spread-Spectrum (DS-SS) is presented, specifically suited for the ionospheric channel Antarctica-Spain.…”

“…Therefore, advanced control systems as fuzzy logic (Zadeh, 1965;1988) are used to solve this complex acquisition problem. The fuzzy logic estimator used in this chapter was first presented by our research group in (Alsina et al, 2005a) and (Alsina et al, 2008;2007b;2009b); in this study, a new control system with a new set of If-Then Rules is presented to cope with the multipath time-variant ionospheric channel (Alsina et al, 2009a).…”

“…Previous work started with the design of a fuzzy control for a serial search algorithm based on a CFAR scheme (Glisic, 1991), work presented in (Alsina et al, 2005a). Afterwards, the fuzzy estimator was adapted to the multiresolutive structure (Morán et al, 2001), in order to improve its performance in channels with fast SNR variations.…”

“…The PN sequence family used to test the four input ratios was designed using evolution strategies (Alsina et al, 2007b;2005a), in order to satisfy the requirements of the multiresolutive structure (as shown in Figure 2 and in Section 3). This structure uses a decimated PN sequence to estimate the first acquisition point, and therefore it is convenient to obtain good autocorrelation for the decimated sequence, as well as a limited crosscorrelation between the M decimated versions of the PN sequence.…”