Inter-symbol interference cancellation for wireless multiple access

Abstract

An interference-canceling receiver is configured for cancelling inter-symbol interference due to both inter- and intra-channel interference in coded, multiple-access, spread spectrum transmissions that propagate through frequency-selective communication channels. The receiver mitigates the effects of post-cursor inter-symbol interference using feedback of previously estimated symbols, and mitigates pre-cursor inter-symbol interference using an interference canceller, such as an iterative interference canceller.

1 . An interference canceller for canceling inter-symbol interference, intra-cell interference, and inter-cell interference in a multiple-access communication signal, comprising:
 a post-cursor inter-symbol interference synthesis module configured for synthesizing an estimated post-cursor inter-symbol interference signal from post-cursor symbol estimates;   a post-cursor inter-symbol interference cancellation module and a resolving module configured for processing the estimated post-cursor inter-symbol interference signal and the received signal to produce a first interference-canceled signal;   an interference cancellation module configured for canceling pre-cursor inter-symbol interference, intra-cell interference, and inter-cell interference from the first interference-cancelled signal for producing interference-cancelled symbol estimates and the post-cursor symbol estimates; and   a feedback loop configured for coupling the post-cursor symbol estimates to the post-cursor inter-symbol interference synthesis module.