Summary: 1
The Finite­Length Multi­Input Multi­Output MMSE­DFE
Naofal Al­Dhahir and Ali H. Sayed
Abstract
A new theoretical framework is introduced for analyzing the performance of a finite--length minimum--mean--square--
error decision feedback equalizer (MMSE--DFE) in a multi--input multi--output (MIMO) environment. The framework
includes transmit and receive diversity systems as special cases and quantifies the diversity performance improvement
as a function of the number of transmit/receive antennas and equalizer taps. Fast and parallelizable algorithms for
computing the finite--length MIMO MMSE--DFE are presented for three common multi­user detection scenarios.
Keywords : Equalizers, FIR digital filters, MIMO systems, Mean square error methods
I. Introduction
In multi--user communication over linear, dispersive, and noisy channels, the received signal is com­
posed of the sum of several transmitted signals corrupted by inter--symbol interference (ISI), inter--user
interference (IUI), and noise. Examples include TDMA digital cellular systems with multiple trans­
mit/receive antennas [25], [4], wide--band asynchronous CDMA systems [3], where IUI is also known
as multiple access interference (MAI), wide--band transmission over digital subscriber lines (DSL)
[1], where IUI takes the form of near--end and far--end crosstalk between adjacent twisted pairs, and
high--density digital magnetic recording where IUI is due to interference from adjacent tracks [15].
This work is motivated by the desire to increase the capacity of digital TDMA wireless networks
by allowing multiple transmissions sharing the same time slot and frequency band and separating

Source: Al-Dhahir, Naofal - Department of Electrical Engineering, University of Texas at Dallas

Collections: Engineering