This paper studies optimal power allocation to minimize symbol error rate (SER) of amplify-and-forward cooperative diversity networks. First, we analytically solve optimal power allocation problem to minimize SER for three different scenarios, namely, multi-branch single-relay, single-branch multi-relay and multi-branch multi-relay cooperative diversity networks, all subject to a given total re...

in this paper two different rateless transmissionschemes are developed. in the proposed scheme, relay node candecode and forward the message to the destination if they areable to decode it, or amplify and forward the message to thedestination. based on the analysis and simulation resultsprovided in this paper, the proposed method has bettertransmission time than the scheme which only the relay ...

wireless sensor networks are composed of hundreds or thousands of small nodes called sensor that work together and are associated with a specific task or tasks to do. each of these nodes includes sensor, processor, communication components, a small memory and a source of energy. it is expected that wireless sensor networks will be used widely in many applications in near future. scalability and...

In this paper, our objective is maximizing total sum-rate subject to power constraints on total relay transmit power or individual relay powers, for amplify-and-forward single-antenna relay-based wireless communication networks. We derive a closed-form solution for the total power constraint optimization problem and show that the individual relay power constraints optimization problem is a quad...

IEEE 802.16 standard is created to compete with cable access networks. In the beginning end users are immobile and have a line of sight with base station, now it moved to mobile non line of sight (NLOS) with the new standard IEEE 802.16e and IEEE 802.16j. The new IEEE 802.16j standard which is an amendment to IEEE 802.16e is mobile multi hop relay (MMR) specification for wireless networks. This...

The paper studies the capacity of the OFDM and the OFDMA relay networks. Two relay schemes, amplify-and-forward (AF) relay and decode-and-forward (DF) relay are analyzed and compared for both OFDM and OFDMA relay networks. A relay node selection algorithm is proposed for OFDMA relay network. Numerical results show that under small relay power transmission, AF outperforms DF while the opposite i...

Multi-hop relaying deployment are expected to offer coverage extension and throughput enhancement to fulfill the staggering increase in mobile broadband traffic, while reducing the total energy consumption in heterogeneous cellular networks, namely joint macro basestation-relay networks. This paper investigates the impact of relay deployment in long termevolution advanced (LTE-Advanced), as a s...

In this paper, an iterative incremental relay selection (IIRS) scheme is considered for wireless cooperative networks in order to increase the reliability of transmission. Different from the conventional incremental relay selection which incrementally selects a best relay for only one iteration; the IIRS scheme iteratively applies the incremental relaying and relay selection processes. To evalu...

Network coding technique increases wireless network communication efficiency. Wireless multihop relay network has been shown to achieve capacity gain over conventional single-hop wireless networks. Hybrid wireless relay networks integrate multihop ad hoc relay and infrastructure base stations to achieve better wireless network performance. Applying the promising network coding technique to hybr...

Link adaptive relaying (LAR) is one of the most popular techniques which employs soft power scaling approaches at the relay nodes. On the other. Buffer-aided relaying is a new paradigm for wireless cooperative networks. Buffer-Aided Relaying With Adaptive Link Selection – Fixed and Mixed Rate. A wireless relay is a codecadaptive RF receiver with single channel relay. It helps easily deployment ...