We consider the uncoded transmission over the halfduplex single relay channel, with a single antenna at the source, relay and destination nodes, in a Rayleigh fading environment. The phase during which the relay is in reception mode is referred to as Phase 1 and the phase during which the relay is in transmission mode is referred to as Phase 2. The following two cases are considered: the Non-Or...

An optimization procedure for the location of the relay transceiver in ultrawideband wireless communication system is presented. The impulse responses of different transceiver locations are computed by shooting and bouncing ray/image (SBR/Image) techniques and inverse fast Fourier transform (IFFT). By using the impulse responses of these multi-path channels, the bit error rate (BER) performance...

Relay Selection and Resource Allocation in One-Way and Two-Way Cognitive Relay Networks Ahmad Mustafa Alsharoa In this work, the problem of relay selection and resource power allocation in oneway and two-way cognitive relay networks using half duplex channels with di↵erent relaying protocols is investigated. Optimization problems for both single and multiple relay selection that maximize the su...

In this article, we develop an analytical framework for the performance analysis of cooperative amplify-and-forward (CAF) relay-based energy detection. We derive mathematical expression for the detection probability for single cognitive relay system and later extend it to multi-relay system. Our resulting expression is based on the canonical series representation of generalized Marcum Q-functio...

We apply the concept of artificial and controlled interference in a triangular relay network with an untrusted relay aiming at enhancing the wireless communication secrecy between the source and the destination node. In order to shield the square quadrature amplitude modulated (QAM) signals transmitted from the source node to the relay, the destination node designs and transmits artificial nois...

The secure wireless communication has been an important field of research. The proposed max-ratio relay selection techniques introduced to security of transmission in buffer aided cooperative wireless network. The data transmitted from source to relay and relay to destination. An eavesdropper can used to intercept the data from source to relay and relay to destination. Assume, data buffer are a...

In cooperative relay networks, the selected relay nodes have great impact on the system performance. In this paper, a multi-relay selection schemes that consider both single objective and multi-objective are proposed based on evolutionary algorithms. First, the single-objective optimization problems of the best cooperative relay nodes selection for signal-to-noise ratio (SNR) maximization or po...

In this paper, we propose a robust relay precoder in the multiple operator relay sharing system, where multiple base stations transmit to their target user terminals simultaneously with the assistance of an amplify-and-forward relay. The base stations and the user terminals are equipped with single antennas while the relay employs multiple antennas. The channel state information at the relay is...