Performance of Space-Time Codes: Gallager Bounds and Weight Enumeration

Since the standard union bound for space-time codes may diverge in quasi-static fading channels, the limit-before-average technique has been exploited to derive tight performance bounds. However, it suffers from the computational burden arising from a multi-dimensional integral. In this paper, efficient bounding techniques for space-time codes are developed in the framework of Gallager bounds. Two closed-form upper bounds, the ellipsoidal bound and the spherical bound, are proposed that come close to simulation results within a few tenths of a decibel. In addition, two novel methods of weight enumeration operating on a further reduced state diagram are presented, which, in conjunction with the bounding techniques, give a thorough treatment of performance bounds for space-time codes.

• Type: Journal
• Year: 2008
• Where: TIT
• Authors: Cong Ling, Kwok H. Li, Alex ChiChung Kot
• Keywords: Efficient Bounding Techniques, Quasi-static Fading Channels, Space-time Codes, TIT 2008