This letter proposes a robust detection scheme of orthogonal space-time block codes that face very fast fading channels. The proposed detection scheme employs a QR decomposition on the channel matrix and minimizes noise enhancement and impact of channel estimation errors which occur in a conventional detection scheme. It is shown by simulations that the proposed detection scheme outperforms the...

ii PhD Thesis by Gbenga Owojaiye University of Hertfordshire, Hatfield, Herts. AL10 9AB, United Kingdom Abstract In this thesis, space-time block codes originally developed for multiple antenna systems are extended to cooperative multi-hop networks. The designs are applicable to any wireless network setting especially cellular, adhoc and sensor networks where space limitations preclude the use ...

Multiple-input multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) is known as a promising solution for wideband wireless communications. This is why it has been considered as a powerful candidate for IEEE 802.11n standard. Numerous spacefrequency block codes (SFBCs) and space-time-frequency block codes (STFBCs) have been proposed so far for implementing MIMO-OFDM systems. In...

We present a new architecture of layered space-time codes as a combination of BLAST architecture and of special STTC codes which are variations about the codes first introduced by Jafarkhani et al. and named Super Orthogonal Space-Time Trellis Codes (SOSTTC). Using powerful set partitioning, these codes are able to combine the coding advantage of STTC’s together with the advantage diversity of ...

Employing space-time block codes in Orthogonal Frequency Division Multiplexing (OFDM) can effectively improve the system performance. The straightforward implementations, including space-time coded OFDM and space-frequency coded OFDM, require the separate inverse discrete Fourier transform (IDFT) operation for each transmitter. In this paper, we propose a low complexity implementation of four-a...

The performance limits of scalar coding for multiple-input single-output channels are revisited in this work. By employing randomized beamforming, Narula et al. demonstrated that the loss of scalar coding is universally bounded by ∼ 2.51 dB (or 0.833 bits/symbol) for any number of antennas and channel gains. In this work, by using randomized beamforming in conjunction with space-time codes, it ...

Multiple-Input multiple-output (MIMO) technology is capable of enhancing capacity and coverage of wireless links. Implementation of MIMO devices is intricate because of the increased number of radio frequency chains (one for each antenna element). Antenna selection is one attractive approach to mitigate this requirement. It only utilizes an optimal subset of all available antennas, adapting it ...