Title :
Enhanced Soft-Handover for DS-CDMA Systems using Complementary Error Correction Codes
Author :
El Aoun, Moustapha Ould ; Siala, Mohamed ; Boujemâa, Hatem
Author_Institution :
TECHTRA Res. Unit, Higher Sch. of Commun. of Tunis, El Ghazala
Abstract :
In order to enhance soft-handover performance in the downlink of DS-CDMA systems, we propose to use different codes at the base stations in the active set to encode the information sequence targeted to a mobile station. For reliable information recovery, in case all links except one happen to be simultaneously in deep fade, self-decodable complementary punctured convolution codes, inspired from Hybrid ARQ III, are used. When turbo-decoding is feasible at the mobile station, new complementary codes, using different interleavers followed by a common systematic recursive convolutional encoder, are proposed for an additional enhancement in performance. Experimental evaluation of the enhancement in performance provided by complementary coding is carried for both Gaussian and multipath Rayleigh fading channels. The proposed coding schemes can provide very significant gains. In some cases, gains around 4 dB can be achieved.
Keywords :
Gaussian channels; Rayleigh channels; automatic repeat request; code division multiple access; convolutional codes; error correction codes; turbo codes; DS-CDMA systems; Gaussian channels; Hybrid ARQ III; base stations; convolution codes; error correction codes; mobile station; multipath Rayleigh fading channels; recursive convolutional encoder; soft-handover; turbo-decoding; Base stations; Convolution; Convolutional codes; Error correction codes; Fading; Interleaved codes; Mobile antennas; Modulation coding; Multiaccess communication; Rayleigh channels;
Conference_Titel :
Vehicular Technology Conference, 2009. VTC Spring 2009. IEEE 69th
Conference_Location :
Barcelona
Print_ISBN :
978-1-4244-2517-4
Electronic_ISBN :
1550-2252
DOI :
10.1109/VETECS.2009.5073537
