Improved Performance Upper Bounds for Terminated Convolutional Codes in Rayleigh Fading Channels

Abstract

This paper presents improved performance upper bounds for terminated convolutional codes over Rayleigh fading channels with BPSK and QPSK modulation. The conventional union bound derived from the transfer function becomes loose when the convolutional code is terminated by a ¯nite-length information sequence followed by additional tail bits. We use the modi¯ed trellis approach to derive tighter upper bounds for terminated convolutional codes combined with BPSK modulation over Rayleigh fading channels. Furthermore, we derive the weight enumerators for rate-1=2 terminated convolutional codes with QPSK modulation and present tighter upper bounds over Rayleigh fading channels.