Novel Results on 3G Reconfigurable Outer Block Interleaving Based on FER

Outer block interleaving and time transmission interval (TTI) are two interrelated parameters for the design of 3G systems. Particularly, they represent a critical issue for the implementation of UMTS turbo coding in flat Rayleigh fading channels. Thus, an efficient TTI choice can save computational complexity. In this paper different scenarios are investigated using the maximum UMTS frame length and simulation results are presented for the four possible outer block interleaver configurations in the case of flat Rayleigh fading channel. Considering frame error rate (FER) performance we propose a TTI of 80 ms for rural and urban/suburban outdoor operating environments for the majority of scenarios. For indoor/low range outdoor operating environment 20 ms is the proposed choice apart from low data rates.