Extended orthogonal space-time coding can use feedback of channel state information to increase the diversity gain of the transmission. This paper calculates the maximum attainable gain, and shows the effect that quantisation in the feedback channel has on the system performance. We demonstrate that for slow-fading channels, differential coding with a single feedback bit can achieve near-optimum performance and exceed the performance of non-differential feedback with higher word length. We also comment on combining differential encoding with channel estimation. Simulation results compare this approach to state-of-the-art systems with standard quantised and unquantised feedback

This paper focuses on the enhancement of extended orthogonal space-time block coding (EO-STBC) when transmitting over a doubly-dispersive channel. The frequency selective nature of the channel favours the combination with a multicarrier approach such as orthogonal frequency division multiplexing (OFDM). However, as Doppler spread increases, OFDM loses its orthogonality, resulting in severe inter-symbol (ISI) and inter-carrier interference (ICI). This is addressed firstly by the generalisation of OFDm to fractional Fourier transform (FrFT)-based multicarrier approaches, which can provide better resilience in the presence of Doppler spread. Secondly, in higher mobility scenarios, an equalisation scheme is employed, whose lower complexity in an FrFT-based multicarrier setting can further minimised by a reduction of the equaliser. Simulation results highlighting the potential performance improvements are presented

The most widely two Renewable Energy Sources (RESs) used are solar and wind as naturally found sources due to the provided merits as clean, free of charge, and environmentally friendly. However, they are facing limitations in intermittency. This article aims to utilize natural resources integrated with the utility grid and Electric Vehicle (EV) to provide a hybrid system with a minimum of two objectives namely Cost of Electricity (COE) and reliability using the Losses Power Supply Probability (LPSP) method. The two mentioned objectives are considered to satisfy the residential load demand with EV in terms of Vehicle-to-Grid (V2G) as this article considered. The mentioned objective has been addressed by the Improved Antlion Optimization Algorithm (IALO) and coupled with a high supervisory control method called Rule-Based Energy Management Strategy (RB-EMS) to guarantee to spread the power among the system component. Optimization results show the hybrid integration of the utilized RESs with the Battery (BT) gives the most economic and reliable system for the study area integrated with the EV battery. The gained result was validated with a natural-inspired metaheuristic algorithm called Particle Swarm Optimization (PSO). This article assesses the effect on the RESs generators to achieve an economic and reliable system.

Abstract-Extended orthogonal space time block coding (EO STBC) can achieve high transmit diversity over a multiple input mUltiple-output (MIMO) channel. To do so, it requires channel state information on the transmitter side, which needs to be estimated and fed back from the receiver. Therefore, this paper explores an estimation and tracking scheme by means of a Kalman ilter, which is integrated with EO-STBC detection and exploits the smooth evolution of the channel coeicients by applying differential feedback. For slow fading, we propose the inclusion of a drit vector in the Kalman model, which is motivated by a second order approximation of the underlying channel model and can be shown to offer advantages in terms of temporal smoothness when addressing channels whose coeicient trajectories evolve smoothly.