Future Wireless Networks are expected to adopt multi-user multiple input multiple output (MU-MIMO) systems whose performance is maximized by making use of precoding at the transmitter. This chapter describes the recent advances in precoding design for MU-MIMO and introduces a new technique to improve the precoder performance. Without claiming to be comprehensive, the chapter gives deep introduc...

Energy efficiency (EE) is becoming more and more important in future wireless communications because of limited battery power in mobile terminals. In this paper, we compare EE of the distributed MIMO (D-MIMO) and co-located MIMO (C-MIMO) in uplink systems. Taking into account both circuit and transmit power, we derive an analytical expression for EE of D-MIMO and C-MIMO systems in a composite R...

Cooperative multiple-input multiple-output (MIMO) relaying is investigated in the paper. We introduce DFAF selection MIMO relaying, where the relay equipped with multiple antennas can adaptively switch between decode-and-forward (DF) and amplify-and-forward (AF) according to its decoding state of the sourcemessage. We consider two wireless environment scenarios: 1)The scenario with traditional ...

Finite-length delay-optimized multi-input multi-output (MIMO) equalizers that optimally shorten the impulse response memory of frequency-selective MIMO channels are derived. The MIMO equalizers are designed to minimize the average energy of the error sequence between the equalized MIMO channel impulse response and an MIMO target impulse response (TIR) with shorter memory. Two criteria for optim...

Multiple Input Multiple Output (MIMO) systems have been an important area for future wireless systems, as it can provide high capacity, good diversity and less interference. This technique is very attractive for wireless communication to increase data rates and system performance. A radio propagation channel is a one that gives the characteristics of MIMO systems. Different approaches have been...

Motivated by MIMO broad-band fading channel model, in this section a comparative study is presented regarding various uncoded adaptive and non-adaptive MIMO detection algorithms with respect to BER/PER performance, and hardware complexity. All the simulations are conducted within MIMO-OFDM framework and with a packet structure similar to that of IEEE 802.11a/g standard. As the comparison result...

A MIMO-OFDM receiver requests high-speed MIMO detection to separate spatially multiplexed signals on real-time processing, which causes large power dissipation due to its high throughput performance. We present an adaptive MIMO detector which adaptively changes the computational speed of MIMO detection by estimating Doppler shifts correlated with fading channel variations. The adaptive detector...

A novel multiband multiple-input-multiple-output (MIMO) antenna system is proposed. The MIMO antenna system consists of two antenna elements, each of which comprises of three radiators: a driven monopole, an S-shaped strip and an inverted F-shaped strip and occupies footprint of 15x18.5x0.8 mm3 only. The driven monopole acts as a quarter-wave monopole and stimulate higher mode resonance. The tw...

This paper describes low-power dynamic multiple-input and multiple-output (MIMO) detection for a 4×4 MIMO-orthogonal frequency-division multiplexing (MIMO-OFDM) receiver. MIMO-OFDM systems achieve high-speed and large capacity communications. However, they impose high computational cost in MIMO detection when separating spatially multiplexed signals and they consume vast amounts of power. We pr...