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Energy efficiency is crucial in wireless communications. In this work, we compare strategies for packet delivery in a network composed of a single source and two destinations. Two transmission schemes are used: Automatic Repeat Request (ARQ) and Random Network Coding (RNC). We define the cost associated with each strategy as the expected energy spent per successfully delivered packet. Then, we optimize...
In this paper, we propose a precoder using a minimum mean-square error (MMSE) criterion for a non-regenerative relay system. It is assumed that the relay knows the channel covariance information (CCI) of the relay-destination link and the full channel state information (CSI) of the source-relay link. We start by assuming the precoder has a specified structure. We derive an upper-bound of the mean-square...
Recently, the concept of self-organization has drawn considerable attention for its possible use in distributed interference management. To realize self-organized interference management, a minority game (MG) is a promising tool because it facilitates self-organized decision-making. Although the existing interference management scheme that involves the use of an MG achieves transmission control aware...
Wireless sensor networks may be utilized for various application areas such as health, military, home, and so on. In the wireless sensor networks, data transmission typically relies on multi-hop communication with high packet loss rates on wireless links so that reliable end-to-end data transmission is desirable. Recently, in order to achieve desired Communication Reliability (CR) levels of the various...
During the last few years, several authors have studied the performance of many different types of channel codes for cooperative communication systems. Some of these codes include Low Density Parity Check (LDPC), Turbo and convolutional codes. Published results show that these codes effectively improve both the data rate and system performance in cooperative schemes such as the decode and forward...
In this paper, we study the performance of time reversal (TR) pre-equalization technique in terms of outage probability for downlink multi-cellular wideband indoor communication environments. We derive a closed form expression of the cumulative distribution function (CDF) of the output signal to interference ratio (SIR) or equivalently the outage probability. This expression allows for faster and...
IEEE 802.22 is the first worldwide Wireless Regional Area Networks (WRAN) standard based on cognitive radios (CR). In IEEE 802.22 WRAN, if a wireless microphone appears in any TV channel, the whole channel should be cleaned. 802.22 WRAN devices probably need to fractionally use the first adjacent channel for improving spectrum efficiency while ensuring no harmful interference is caused to the wireless...
This paper addresses the spectrum-sharing for wireless communication with a licensee-primary and a secondary users interfering with each other. We propose a new practical power control policy for the secondary user, under outage performance requirements for both users, with partial knowledge of channel state information.
In this paper, we present a novel application of matrix game theory for optimization of link scheduling in wireless ad-hoc networks. Optimum scheduling is achieved by soft coloring of network graphs. Conventional coloring schemes are based on assignment of one color to each region or equivalently each link is member of just one partial topology. These algorithms based on coloring are not optimal when...
The recently allocated 71-76 GHz and 81-86 GHz bands provide an opportunity for Line Of Sight (LOS) links for directional point-to-point “last mile” links. An efficient use of this spectrum may allow wireless to finally “catch up” with wires, leading to systems such as “multi-Gigabit wireless Ethernet,” and “wireless fiber.” However, the transmission at such a frequency range is characterized by several...
We study the physical layer design of a distributed time-division multiple access (TDMA) protocol for wireless body area networks (WBAN). The distributed TDMA scheme is derived from a bio-inspired algorithm known as Pulse-Coupled Oscillator (PCO), in which each node in the network updates its state based on its knowledge of the neighborhood. ON-OFF ultra wide band (UWB) modulation is used by the sensors...
This paper presents the vision shared by partners from the CELTIC project HOMESNET about Femto Base Station deployed at Home, i.e. Home Base Station (HBS). Three of the main aspects under study are presented. The challenges in HBS self-organizing, including femto-macro coexistence, are explained and methodology for successful self-organization is proposed. To achieve very low radio emission at home...
Along with LTE-Advanced system and standardization investigation progress, the requirement for verifying relevant key technologies become more and more urgent. This article summarizes the progress of Huawei 4G Test-bed “HEART” (Huawei Experimental Advanced Radio Test-bed). CoMP technology is considered as a launch point to build up this test-bed competence. Some initial analysis and results are addressed...
Future pervasive communication systems requirements for highly performing, flexibly deployable and cost/energy-efficient services and applications are expected to revolutionize the way we design, optimize and use wireless networks. From a cellular perspective, the emphasis is placed on achieving ubiquitous and reliable real-time data communications at cell-edge, as articulated in ITU's IMT-Advanced...
This paper proposes a number of novel uses for 3D location and environmental geometry information to enhance the performance of the wireless physical layer. In the context of this paper, such information is obtained in real-time from a mobile operative carrying the ViewNet system. A location-based multi-user scheduler is proposed to exploit multi-user diversity by choosing users with wide angular...
The information and communications technologies world is migrating towards the Future Internet (FI) era. Operators will have increased complexity to address in the FI era, compared to today, in the management of their infrastructure and services. This is due to the extended set of applications that should be supported and to the more options offered by the infrastructure. Cognitive management systems...
Exact average capacity results for L-branch coherent equal-gain combining (EGC) in correlated and uncorrelated fading channels are not known. This paper develops a novel framework (approach) for capacity analysis of L-branch EGC in generalized fading channels. In addition, Gamma shadowed generalized Nakagami-m fading model is proposed in order to statistically model the fading environments in high...
This paper studies the performance of a superposition based approach for multi-user access in the uplink of a wireless cell. The approach uses non-orthogonal signaling and multi-user detection on top of an orthogonal multiple-access method like OFDMA. Path losses depending on the distance between a terminal and the base station and cancellation errors during multi-user detection are taken into account...
We consider the problem of multicasting from a single source to a set of destinations. We assume that the source cannot reach the destinations directly, but must forward its traffic through a set of relays. Under the performance objective of maximizing the common amount of information (number of bits) that the source sends to all destinations per Joule of the total energy spent, we wish to obtain...
Wireless location refers to obtaining the position information of a mobile subscriber in a cellular environment. Such positioning information is usually provided in terms of geographic coordinates of the mobile subscriber with respect to a geographic reference point. Wireless location finding has emerged as an essential feature of cellular systems and has many potential applications in areas such...
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