A performance study of Multiframe Interleaving for CDMA2000 1X cellular system

Abstract

Multiframe Interleaving (MFI) is the support of 40 and 80ms supplemental channel frames for CDMA2000 1X. Longer frames improve interleaver performance by separating adjacent symbols further in time and thus require less E[sub]b/N[sub]t, in burst noise conditions, to maintain a target FER at a given data rate. The overall benefit is to improve throughput capacity for today's high bandwidth cellular services. This thesis analyzes the average power usage and data throughput with longer frames for various channel models and radio configurations. Through experimental and simulative testing in a laboratory setting, MFI is shown to use less power per unit of throughput at the link layer in slow fading, single path channel environments. However, gains over 20ms frames diminish for faster fading and multipath, and the limitation of the forward link scheduler in accurately predicting channel conditions handicaps any gains at the link level.