Driven by the fast-growing demand on wireless applications, cooperative relaying has recently received much attention. In this dissertation, cooperative relaying in MIMO systems and sensor networks is studied extensively, with focus on capacity bounds and scaling laws. The first thrust is on the capacity bounds of MIMO relay channels. First, a Gaussian MIMO relay channel model with fixed channe...

Extended Abstract: Cooperative communication is now widely known as a promising technique for realizing distributed spatial diversity in modern wireless networks. To achieve various performance advantages benefiting from user cooperation, knowledge of the system parameters at the relay and destination terminals is typically required. For example, to implement the distributed beamforming/precodi...

In this paper, we present a coding strategy for wireless relay networks, where we assume no channel knowledge. More precisely, the relays operate without knowing the channel that affected their received signal, and the receiver decodes knowing none of the channel paths. The coding scheme is inspired by noncoherent differential space-time coding, and is shown to yield a diversity linear in the n...

In this paper, we study the emergence of topological interference alignment and the characterizing features of a multi-user broadcast interference relay channel. We propose an alternative transmission strategy named the relay space-time interference alignment (R-STIA) technique, in which a K -user multiple-input-multiple-output (MIMO) interference channel has massive antennas at the transmitter...

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...