To detect spatially-modulated signals, a receiver needs the channel state information (CSI) about each transmit-receive antenna pair. Although the CSI (or channel response information) is never perfect and varies in time, most studies on spatial modulation (SM) systems assume perfectly known CSI and time-invariant channel. The spatial correlations among multiple spatial subchannels, which have ...

This paper presents a novel approach to investigate ergodic mutual information of OFDMA Selection-Decode-and-Forward (SDF) cooperative relay networks with imperfect channel state information (CSI). Relay stations are either dedicated or non-dedicated (i.e., subscriber stations assisting other subscriber stations). The CSI imperfection is modeled as an additive random variable with known statist...

Mobile channels suffer from multipath fading and necessitate transmitter adaptation to achieve Shannon capacity. The capacity achieving transmitter adaptation strategy depends on how much channel side information (CSI) is available at the transmitter (CSIT) and the receiver (CSIR). When CSI is perfectly known at both sides, it is shown in [10] that for AWGN channels with flat fading, the optima...

In order to increase the data rate or power efficiency of OFDM systems several adaptive strategies to select the power, modulation and even code rate on a per subcarrier basis have been discussed in literature. The underlying assumption of perfect channel state information (CSI) at the transmitter, however, is hardly fulfilled in practical systems. Hence, either existing approaches have to be m...

With the advent of 5G and need for energy-efficient massively connected wireless networks, in this work, we consider an energy harvesting (EH) based multi-relay downlink cooperative non-orthogonal multiple access (NOMA) system with practical constraints. The base station serves NOMA users help decode-and-forward EH relays, where relays harvest from station's radio frequency. A relay is selected...

Using information about the channel at the transmitter can improve the performance of multi-input multi-output (MIMO) communication systems. When perfect channel state information (CSI) is available, data can be multiplexed and optimized over independent spatial channels. However, when the available channel information is imperfect or partial, crosstalk between the spatial channels is inevitabl...

Traditional beamforming and power control algo-rithms in cognitive radio (CR) are based on the assumption of perfect channel state information (CSI) however; this may lead to performance degradation in realistic systems. In this paper, the problem of joint beamforming and power control is investigated in underlay CR networks with imperfect CSI. Our objective is to maximize the sum utility of se...

In this paper, we will analyze the energy efficient power loading in MIMO-SVD architecture. Existing power loading schemes are developed on assumption that a scheduler possesses perfect channel state information (CSI). But we take into account the effects of channel estimation error (CEE) and propose a robust energy-efficient power loading for MIMO system under imperfect CSI. We propose two alg...

A threshold based opportunistic relaying cooperative communication protocol has been analysed in this thesis. The relay is selected opportunistically to maximize the end-to-end signal to noise ratio received at the destination. The relay selection may be proactive and reactive. The underlying communication protocol at relay is decode and forward cooperation. At destination Maximal Ratio Combini...