This paper deals with the capacity behavior of wireless orthogonal frequency-division multiplexing (OFDM)-based spatial multiplexing systems in broad-band fading environments for the case where the channel is unknown at the transmitter and perfectly known at the receiver. Introducing a physically motivated multiple-input multiple-output (MIMO) broad-band fading channel model, we study the influ...

A multiple-input multiple-output (MIMO) communication system combined with the orthogonal frequency division multiplexing (OFDM) modulation technique can achieve reliable high data rate transmission over broadband wireless channels. Channel state information for both single-input single-output (SISO) and MIMO systems based on pilot aided arrangement is investigated in this paper. The estimation...

Multiple input multiple output (MIMO) techniques are expected to be widely employed in wireless communications to address the ever-increasing demand for capacity. MIMO systems provide a linear increase in capacity with the number of antenna elements, affording significant increase in capacity over single input single output (SISO) systems. In this paper, we discuss some of the most basic detect...

In this paper, we propose a differential space-time modulation (DSTM) scheme for multiple input multiple output (MIMO) systems with 2, 4, and 8 transmit antennas. This scheme is used for MIMO systems where the channel coefficients are not available at both the transmitter and the receiver. For 2 transmit antennas, the transmission matrices are selected from Weyl group. We use the Kronecker prod...

Multiple input multiple output (MIMO) is a technology that enhances wireless systems capacity, data rate, and coverage by utilizing the spatial diversity provided by multiple antennas. However, these benefits come at the expense of increased computational complexity. Implementing a broadband MIMO wireless communication system in a real-time testbed is a challenging task, entailing numerous pitf...

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...

In recent years, Multi-Input Multi-Output (MIMO) communications are introduced as an emerging technology to offer significant promise for high data rates and mobility required by the next generation wireless communication systems. Using multiple transmit as well as receive antennas, a MIMO system exploits spatial diversity, higher data rate, greater coverage and improved link robustness without...

The number of channel estimates that have to be estimated in Multiple-Input Multiple-Output (MIMO) system is in general much larger, than in a single antenna communication scheme. This leads to lower signal to noise ratios (SNR) of the channel estimates if a constant pilot power independent from the number of transmit antennas is assumed. The use of long-term spatial channel characteristics can...

In wireless communications systems, Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) are used to improve spectral efficiency and spatial diversity. Beamforming is used to improve bandwidth utilization. It increases the network range in wireless systems. The main challenge of OFDM system is Carrier frequency offset (CFO). The project focuses on CFO esti...

Bitand power allocation techniques for Multiple-Input Multiple-Output (MIMO) systems are investigated for minimizing the overall bit-error rate (BER) at a fixed data rate. In this work optimal power allocation (PA) technique based on the Lagrange multiplier method is studied and compared with suboptimal solutions. Our results obtained by computer simulations show that power allocation works ver...