Bit Error Probability For Direct-Sequence Spread-Spectrum In A Shadowed Rician Fading Land Mobile Satellite Channel With Diversity

Abstract

The bit error probability is analyzed €or direct-sequence spread-spectrum transmission in a land mobile satellite channel using coherent binary phase shift keying (BPSK) modulation. The influence of diversity on the bit error probability is investigated. Two types of diversity are considered, namely selection diversity (SD) and maximal ratio combining (MRC), and the results are compared. 1.0 INTRODUCTION. Land mobile satellite communication can provide various applications, e.g. voice, data, position finding and paging services, interconnection to the public switched telephone network, and the possibility of private networks [l]. Measurements show [2,3] that the land mobile satellite channel can be approximated as a shadowed Rician fading channel in rural and suburban environments. The channel modeled in [ 2 , 3 ] is appropriate for narrow-band applications. The purpose of this paper is first to extend the model for the use of spread-spectrum modulation. Further, the bit error probability is analyzed and evaluated for light, average and heavy shadowing. Finally, the influence of diversity techniques on the bit error probability is investigated. The type of diversity considered in this paper is microscopic diversity (path diversity), which mitigates the effects of multipath fading.