In a wireless transmission network, relay node or intermediate nodes play a very important role. Thus, the use of relay transmission offers significant performance benefits, including being able to achieve spatial diversity through node cooperation and extending coverage without requiring large transmitter powers. In this paper, we consider a Physical-layer Network Coding (PNC) scheme for a two...

Cooperative link layer protocols are typically used in single hop networks. In such protocols, a special node called the relay node helps deliver frames from a source to a destination. The performance benefits of cooperation at link layer can be streamlined into multi-hop networks as well. In multi-hop networks, a frame is sent from an original source to the final destination through a series o...

Channel capacity is usually undetermined in cooperative communication because of the various power allocations. In order to improve the channel capacity, power allocation for tri-terminal cooperative communication is discussed for Gaussian channel gains in EGC model and MRC model. The optimum power allocation algorithm, viewing channel capacity as the destination function, is presented. The pap...

In this work, we investigate the stability region, the throughput performance, and the queueing delay of an asymmetric relay-assisted cooperative random access wireless network with multipacket reception (MPR) capabilities. We consider a network of N saturated source users that transmit packets to a common destination node with the cooperation of two relay nodes. The relays are equipped with in...

We consider a source-destination pair that can only communicate through an untrusted intermediate relay node. The intermediate node is willing to employ a designated relaying scheme to facilitate reliable communication between the source and the destination. Yet, the information it relays needs to be kept secret from it. In this two-hop communication scenario, where the use of the untrusted rel...

In view of the low efficiency and poor coding performance, an active mechanism network coding algorithm based on multi-channel sensing is proposed. The algorithm first establishes a system model to analyze the work pattern of network coding, then selects the minimum sample as cost function and adopts the multi-channel sensing to examine the coding effect of relay node, which makes the network t...

Cooperative relaying is accepted as a promising solution to achieve high data rates over large areas in the future 4G wireless system. In this paper, an adaptive cooperative relay selection algorithm (ACRSA) is presented for fixed relay based cellular networks. According to current user density in a certain cell, when two-hop transmission is adopted, ACRSA adapts selectively between two differe...

In a multi-hop cooperative communication scenario, where a transmitter can transmit a packet directly to the receiver or indirectly through a relay, there is an inherent trade-off between energy and delay. While it may consume more energy to transmit a packet directly to the receiver than transmitting through a relay, the transmission through relay incurs more delay. We consider the MAC layer o...

In this study, we propose a cooperative transmission framework based on Adaptive Modulation and Coding (AMC) cooperative food communication system in Multiple-Input Multiple-Output (MIMO) fading channels. We consider the scenario that consists of one source node, one relay node and one destination node, they all equipped with multiple antennas and employed the adaptive modulation and coding sch...

The performance of an anonymous path can be described using many network metrics – e.g., bandwidth, latency, jitter, loss, etc. However, existing relay selection algorithms have focused exclusively on producing paths with high bandwidth. In contrast to traditional node-based path techniques in which relay selection is biased by relays’ node-characteristics (i.e., bandwidth), this paper presents...