The unavoidable parametrization of the wireless link represents a major problem of the network-coded modulation synthesis in a 2-way relay channel. Composite (hierarchical) codeword received at the relay is generally parametrized by the channel gain, forcing any processing on the relay to be dependent on channel parameters. In this paper, we introduce the codebook design criteria, which ensure ...

Cognitive radio plays a vital role in wireless communication. The cognitive radio composed of a transceiver which is used to check the channel vacancy for communication and avoids busy channels by shifting into unused channel. The scope for spectrum vacancy and area of coverage is increased by using cognitive radio. In cooperative relay network to transmit the primary traffic the primary users ...

Cooperative Diversity can be used by wireless nodes to take the benefit of broadcast nature and inherent spatial diversity of wireless channel to relay messages for each others. This helps to propagate redundant signals over multiple paths, which can be used to combat the channel noise and fading effects. We investigate the use of packet combining in cooperative diversity scenario. In our appro...

Abstract: This letter presents a procedure of the capacity calculation for a multi-relay communication system for the assumed presence of additive white Gaussian noise and the flat fading in the channel. The exact formula for channel capacity as a function of channel parameters and the number of relays is derived. It was confirmed that the capacity of the network can be maintained and energy co...

In this paper, we consider M-ary phase shifting keying (MPSK) and M-ary quadrature amplitude modulation (MQAM) data symbol burst transmission for adaptive decode-andforward (ADF) relay systems over quasi-static Rayleigh fading channels. A burst has pilot symbols and data symbols. From pilot symbols, we can estimate the channel gain and detect each relay node’s transmission mode for ADF schemes....

A cooperative communication in a two-way relay channel is a bidirectional communication between two terminals with the aid of a common relay. In order to improve the performance of the cooperative communication in a two-way relay channel, a network coding can be used to exploit the broadcasting nature of wireless transmission. In [8], it was shown that each individual link can achieve its own c...

Cooperative communication provides a new way of introducing spatial diversity to wireless systems. In order to increase the spectral efficiency of coded cooperative relaying system, the adaptive modulation technique is presented under Rayleigh fading channel in this paper. The source and relay adapt their modulation schemes based on the channel condition of all three links, i.e. source to relay...

We consider a relay channel where a relay helps the transmission of messages from one sender to one receiver. The relay is considered not only as a sender that helps the message transmission but as a wire-tapper who can obtain some knowledge about the transmitted messages. In this paper we study the coding problem of the relay channel under the situation that some of transmitted messages are co...

A state-dependent relay channel is studied in which strictly causal channel state information is available at the relay and no state information is available at the source and destination. The source and the relay are connected via two unidirectional out-of-band orthogonal links of finite capacity, and a state-dependent memoryless channel connects the source and the relay, on one side, and the ...

Cooperative wireless communication has received significant attention during recent years due to several reasons. First, since the received power decreases rapidly with distance, the idea of multi-hopping is becoming of particular importance. In multi-hopped communication, the source exploits some intermediate nodes as relays. Then the source sends its message via those relays to the destinatio...