An iterative MIMO-DFE receiver with MLD for uplink SC-FDMA

Abstract

Single carrier frequency division multiple access (SC-FDMA) based systems such as long term evolution (LTE) uplink experience severe inter symbol interference (ISI) in highly frequency selective channels. The conventional linear receivers such as the linear minimum mean square error(LMMSE) based receiver fail to address this issue, thereby degrading the performance of the system. This paper proposes a new iterative multiple input multiple output decision feedback equalizer (MIMO-DFE) which does not require the estimation of any parameters for canceling ISI. It also derives a closed form expression for the residual noise covariance after equalization which is used for maximum likelihood detection (MLD) across streams. Simulations show that the proposed receiver yields significant performance gains especially in the high signal-to-noise-ratio (SNR) regime with only a modest increase in computational complexity.