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Smart grid (SG) is the next generation electrical power grid which will provide reliable, efficient and secure energy generation and distribution. To achieve these goals, data such as smart meter (SM) information will be sent to the control center for analysis and decision-making. However, the existing data backhaul network has limited coverage and data rates, is inflexible, and has low reliability...
A typical broadcasting protocol for wireless network usually involves fixed transmission power that covers, for example an area within 250 meters (m). However, it is often unnecessary to broadcast using fixed power because a node that needs to be covered may just be 100m away. By reducing the transmission power enough to cover this node, energy expenditure would be reduced, thus, prolonging the lifetime...
This paper evaluates the performance of an opportunistic scheduling scheme for a multiuser two-way relay network, wherein an analog network coding (ANC)-based relay assists the communication between multiple pairs of users. To ensure fairness for each user pair, we consider a scheduler based on maximizing the normalized minimum of the instantaneous signal-to-noise ratios (SNRs) at each user of the...
We investigate the performance of analog network coding (ANC) for multi-hop networks in this paper. With the amplify-and-forward (AF) protocol, relays broadcast the sum of two colliding signals to neighboring nodes, while the source node can subtract its own signal from the colliding signal to obtain the received information. We first give the transmission scheme expressions for the n-node m-frame...
A distributed cooperative multiplexing (DCM) protocol is proposed that offers advantages over cooperative multiplexing protocols. It uses cooperative beamforming with multiple distributed relays to avoid use of interference cancellation at the user terminals. An approximate expression is derived for its outage performance. The protocol is shown to be power efficient, besides leading to increase in...
Cooperative communication is considered a promising technique to increase channel capacity and improve reliability in wireless and cellular networks. However, it also raises a number of serious security issues as malicious nodes may impersonate and affect the integrity of the communication. In this paper, we propose a prevention-based security technique for cooperative communication taking into consideration...
Wireless sensor networks demand the implementation of energy-aware transmission protocols. Recently, cooperative protocols have been suggested for use in sensor networks since they typically require less transmit power than the direct transmission for the same error probability. For sensor networks with short range transmissions, however, the energy consumed in receiving transmissions from cooperative...
Vehicular delay tolerant networks (VDTNs) were proposed as a novel disruptive network concept based on the delay tolerant networking (DTN) paradigm. VDTN network architecture uses vehicles to relay messages, enabling network connectivity in challenged scenarios. Due to intermittent connectivity, network nodes carry messages in their buffers, relaying them only when a proper contact opportunity occurs...
In this paper, we propose a Decode-and-Forward Network Coded (DFNC) multi-user cooperation scheme for orthogonal uplink channels in a wireless network. The network consists of m peers having independent information transmitting to a common destination. Each peer transmits its own data in the first time phase and serves as a relay in the second time phase to transmit the network coded information combining...
Vehicular Ad-hoc NETworks (VANET) are emerging as a promising way to disseminate information among vehicles. As this information can range from safety to infotainment application content, and the vehicular environment has very particular characteristics, the behavior of the network must be effectively studied in order to adapt the transmission mechanisms. This work presents a model for the connectivity...
In this paper, we consider a relay system with a number of potential relay nodes. We propose several relay assignment protocols to select a relay node to help transmit source data so that the average outage probability of the system is reduced. These protocols include: Optimal-Position relay assignment, Nearest-Optimal-Position relay assignment, and Left (Right)-Nearest-Optimal-Position relay assignment,...
Directional broadcast was proposed in VANETs in order to disseminate data to other vehicles efficiently. However, traditional directional broadcast protocols cannot provide good enough efficiency for VANETs, especially in the urban area. In this paper, we propose an efficient road-based directional broadcast protocol for VANETs in urban environment. We avoid misclassification problem that traditional...
One proven solution to improve the reliability of a wireless channel is to use relays. We focus on the estimate-and-forward (EF) relay protocol where the relay node estimates the source symbol and then forwards it to the destination. We assume the soft information sent by the relay is the expected value of the symbol transmitted by the source. With bit-error-rate (BER) as a metric, we show that EF...
Relaying technique has been developed considerable attention in response to improve reliability and to extend wireless network coverage. One of conventional relaying technique, incremental relaying which uses limited feedback from the destination has attracted research attention because of performance and minimization of relay usage. Moreover, optimal power allocation for various relaying schemes...
Routing is one of the most challenging open problems in Vehicular Ad hoc NETworks (VANETs) because of the short-lived wireless connectivity environment. Store-carry-and-forward approach using buses on regular routes is considered as one of the most promising emerging routing policy that can significantly improve delivery performance and reliability in VANETs. While none of existing solutions considers...
Automatic repeat-request(ARQ) protocols for two-way relay systems, where two terminals communicating via a relay node, are investigated in this paper. According to different feedback schedules, we propose three basic ARQ protocols to improve the link reliability for two-way relay systems, namely Relay-only ARQ (Ro-ARQ), Terminal-only ARQ (To-ARQ) and Relay-Terminal ARQ (RT-ARQ). In addition, simulation...
One of the main privacy problems in network communication is lack of anonymity. Much work has been done on this problem in recent years. However, it is a challenge to improve anti-attack ability and degree of anonymity. A new anonymous multiplexing communication protocol, based on IPv6, is proposed in this paper. It utilizes the secret sharing technique to establish multiplexing communication, solves...
In order to achieve cooperative driving in vehicular ad hoc networks (VANET), broadcast transmission is usually used for disseminating safety-related information among vehicles. Nevertheless, broadcast over multihop wireless networks poses many challenges due to link unreliability, hidden terminal, message redundancy, and broadcast storm, etc., which greatly degrade the network performance. In this...
This paper investigates the diversity performance of wireless cooperative networks with multiple parallel relays communicating with the destination over orthogonal channels, and focuses on the amplify-and-forward relaying protocol. The networks under consideration employ two signal-to-noise ratio (SNR) thresholds and multiple hard-decision detections (HDDs) at the destination. One SNR threshold is...
We analyze and compare the performance of two adaptive relaying schemes based on the amplify-and-forward and the decode-and-forward protocols which are employed to improve the performance of collaborative spectrum sensing. As our results show, the proposed schemes allow us to improve the reliability of the communication part of the wireless sensor network. We expect that this in turn will improve...
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