Showing papers by "Mehran Abolhasan published in 2013"

A Review of Routing Protocols in Wireless Body Area Networks

Abstract: Recent technological advancements in wireless communication, integrated circuits and Micro-Electro-Mechanical Systems (MEMs) has enabled miniaturized, lowpower, intelligent, invasive/ non-invasive micro and nanotechnology sensor nodes placed in or on the human body for use in monitoring body function and its immediate environment referred to as Body Area Networks (BANs). BANs face many stringent requirements in terms of delay, power, temperature and network lifetime which need to be taken into serious consideration in the design of different protocols. Since routing protocols play an important role in the overall system performance in terms of delay, power consumption, temperature and so on, a thorough study on existing routing protocols in BANs is necessary. Also, the specific challenges of BANs necessitates the design of new routing protocols specifically designed for BANs. This paper provides a survey of existing routing protocols mainly proposed for BANs. These protocols are further classified into five main categories namely, temperature based, crosslayer, cluster based, cost-effective and QoS-based routing, where each protocol is described under its specified category. Also, comparison among routing protocols in each category is given.

Multihop Relay Techniques for Communication Range Extension in Near-Field Magnetic Induction Communication Systems

Abstract: munications and near field magnetic induction communication (NFMIC) is discussed. Three multihop relay strategies for NFMIC are proposed: Non Line of Sight Magnetic Induction Relay (NLoS-MI Relay), Non Line of Sight Master/Assistant Magnetic Induction Relay1 (NLoS-MAMI Relay1) and Non Line of Sight Master/Assistant Magnetic Induction Relay2 (NLoSMAMI Relay2). In the first approach only one node contributes to the communication, while in the other two techniques (which are based on a master-assistant strategy), two relaying nodes are employed. This paper shows that these three techniques can be used to overcome the problem of dead spots within a body area network and extend the communication range without increasing the transmission power and the antenna size or decreasing receiver sensitivity. The impact of the separation distance between the nodes on the achievable RSS and channel data rate is evaluated for the three techniques. It is demonstrated that the technique which is most effective depends on the specific network topology. Optimum selection of nodes as relay master and assistant based on the location of the nodes is discussed. The paper also studies the impact of the quality factor on achievable data rate. It is shown that to obtain the highest data rate, the optimum quality factor needs to be determined for each proposed cooperative communication method.

SEA-BAN: Semi-autonomous adaptive routing in wireless body area networks

Abstract: Wireless Body Area Network (WBAN), an intelligent health monitoring system, is introduced advanced and integrated applications in the field of medical, fitness, sports, entertainment, military and consumer electronics. In WBAN, due to the limitation in the availability of energy supply, network longevity is a major challenge. Since 80% of total energy is consumed only because of communication purpose in WBAN, routing protocols play a key role towards making such networks energy efficient. In this paper, we propose an energy efficient cluster-based routing protocol for WBANs, named as semiautonomous adaptive routing in wireless body area network (SEA-BAN). SEA-BAN distributes the energy dissipation evenly among the body nodes and enhances the network lifetime. It is not simply a cluster-based routing protocol; it also combines the benefits of direct transmission and multi-hop transmission methods, depending on the energy level and spatial information of the body nodes, to formalize an adaptive routing. Moreover, its centralized operation reduces the computational burden of body nodes. The comparative analysis of our simulation results show that SEA-BAN enhances the network lifetime by more than 2 times when compared to the multi-hop transmission model and about 8.5 times than the direct transmission model.

An energy efficient network coding approach for Wireless Body Area Networks

Abstract: In this paper, we propose a practical network coding approach for wireless body are networks (WBANs) using decode-and-forward relays. In this scheme, namely decode and forward-network coding (DF-NC), each relay linearly combines different messages from different sources to generate one message, and then transmits that message to the destination. Each relay node in DF-NC requires only one transmission time slot to forward its message. Thus, in this approach, energy usage at each relay is minimized compared to existing cooperative schemes without network coding, which require Ns time slots per relay for relay transmissions; where Ns is the number of source nodes. Simulation results show that the proposed DF-NC scheme can achieve near optimal outage probability while minimizing the number of transmissions per node, maximizing the energy efficiency of WBANs, and minimizing the delay.

Optimised relay selection for route discovery in reactive routing

Abstract: On-demand routing protocols have the potential to provide scalable information delivery in large ad hoc networks. The novelty of these protocols is in their approach to route discovery, where a route is determined only when it is required by initiating a route discovery procedure. Much of the research in this area has focused on reducing the route discovery overhead when prior knowledge of the destination is available at the source or by routing through stable links. Hence, many of the protocols proposed to date still resort to flooding the network when prior knowledge about the destination is un-available. This paper proposes a novel routing protocol for ad hoc networks, called On-demand Tree-based Routing Protocol (OTRP). This protocol combines the idea of hop-by-hop routing (as used by AODV) with an efficient route discovery algorithm called Tree-based Optimised Flooding (TOF) to improve scalability of ad hoc networks when there is no prior knowledge about the destination. To achieve this in OTRP, route discovery overheads are minimised by selectively flooding the network through a limited set of nodes, referred to as branching nodes. The key factors governing the performance of OTRP are theoretically analysed and evaluated, including the number of branch nodes, location of branching nodes and number of Route REQuest (RREQ) retries. It was found that the performance of OTRP (evaluated using a variety of well-known metrics) improves as the number of branching nodes increases and the number of consumed RREQ retries is reduced. Additionally, theoretical analysis and simulation results shows that OTRP outperforms AODV, DYMO, and OLSR with reduced overheads as the number of nodes and traffic load increases.

EAR-BAN: Energy efficient adaptive routing in Wireless Body Area Networks

Abstract: Wireless Body Area Network (WBAN), a neoteric intelligent monitoring system, is envisaged to unleash a wave of personalized, advanced and integrated applications in the field of medical, fitness, sports, entertainment, military and consumer electronics. In WBAN, network longevity is a major challenge due to the limitation in the availability of energy supply and routing protocol plays a key role towards making such networks energy efficient. In this paper, we propose an energy efficient cluster based routing protocol for WBANs, named as energy efficient adaptive routing in wireless body area network (EAR-BAN). Although EAR-BAN is a cluster based routing protocol, it also combines the benefits of direct and multi hop transmission methods, depending on the energy level and spatial information of body nodes, to formalize an energy efficient, adaptive and opportunistic routing. Moreover, its centralized operation reduces the computational burden of body nodes.

A cooperative network coding approach to reliable Wireless Body Area Networks with demodulate-and-forward

Abstract: In this paper, a novel cooperative transmission scheme via network coding has been proposed for Wireless Body Area Networks (WBANs) to enhance reliability and throughput. In the proposed scheme, namely Random XOR Network Coding (RXNC), each relay demodulates the received signal from each sensor node and then selects d different coded symbols amongst them and XORs them to generate a network coded symbol. We have found the optimum value of d through an analytical approach by minimizing the probability that an XOR network coded symbol is incorrectly generated. Simulation results show that the proposed RXNC scheme outperforms the no-cooperation and conventional bitwise network coding schemes in all channel signal to noise ratios (SNRs) from 0 dB to 18 dB.

Interference Mitigation in WBANS: Challenges and Existing solutions

Abstract: Wireless Body Area Networks (WBANs) are an exciting new networking technology developed in the recent years with advancements in wireless communication, integrated circuits and Micro-Electro- Mechanical Systems (MEMs). They consist of a number of sensor nodes that are placed in or around the human body. However, their practical deployment requires addressing numerous challenges. WBANs face many stringent requirements in power, bandwidth, and network lifetime which need to be taken into serious consideration in the design of different protocols. In this paper, we investigate the importance of interference mitigation amongst coexisting Wireless Body Area Networks (WBANs). Since, a WBAN is most likely to encounter other WBANs, inter-WBAN interference and scheduling is of utmost importance.

A Tuned Fuzzy Logic Relocation Model in WSNs Using Particle Swarm Optimization

Abstract: In harsh and hostile environments, swift relocation of currently deployed nodes in the absence of centralized paradigm is a challenging issue in WSNs. Reducing the burden of centralized relocation paradigms by the distributed movement models comes at the price of unpleasant oscillations and excessive movements due to nodes' local and limited interactions. If the nodes' careless movements in the distributed relocation models are not properly addressed, their power will be exhausted. Therefore, in order to exert proper amount of virtual radial/angular push/pull forces among the nodes, a fuzzy logic relocation model is proposed and by considering linear combination of the presented performance metric(s)(i.e. coverage, uniformity, and average movement), its parameters are locally and globally tuned by particle swarm optimization(PSO). In order to tune fuzzy parameters locally and globally, PSO benefits respectively from nodes' neighbours within different ranges and all the given deployed area. Performance of locally and globally tuned fuzzy relocation models is compared with one another in addition to the distributed self-spreading algorithm (DSSA). It is shown that by applying PSO to the linear combinations of desired metric(s) to obtain tuned fuzzy parameters, the relocation model outperforms and/or is comparable to DSSA in one or more performance metric(s).

Experimental validation of the CORNER urban propagation model based on signal power measurements in a vehicular environment

Abstract: CORNER is an urban propagation model which simulates the presence of buildings in city scenarios and models radio propagation as a series of reflections and diffractions around buildings. CORNER was validated in the original publication with a series of packet-delivery-ratio measurements. However, the accuracy of these measurements is limited by interference from nearby networks. This paper independently evaluates the CORNER model using signal strength measurements across three separate sites in Sydney and Wollongong. The measurements are analysed and compared with the predicted analytical estimates. The fading model is also analysed with direct measurements. A new CORNER link classification algorithm is also proposed in this paper.

A Case study for choosing proper relocation algorithms to recover large scale coverage hole(s) in wireless sensor networks

Abstract: Coverage holes as large scale en mass and correlated node failures in wireless sensor networks, not only disturb the normal operation and functionality of networks, but also may endanger network’s integrity. Recent trends to use relocation of currently deployed nodes have attracted attention especially where manual addition of nodes are neither feasible nor economical in many applications. The transition from centralized to distributed node relocation algorithm gradually paves away for applications in which nodes are deployed in harsh and hostile environments in absence of central supervision and control. Although, many different relocation algorithms have been devised to address their given applications’ challenges and requirements and they are efficient in reaching their design goals, they may not be similarly responsive to unpredicted and different circumstances may occur in the network. This paper, demonstrates one of such case, DSSA (Distributed Self-Spreading Algorithm) that is mainly applied for balancing node deployments and recovery of small coverage holes. It is shown here that DSSA is not able to fully recover large scale coverage holes even if all nodes participate in recovery process and relocate with sufficient number of iterations.

Outage probability of multihop relay networks

Abstract: In this paper we analyze the outage performance of a multihop cooperative relay network where relays in the system can change positions dynamically and use all possible links to forward the message to the next hop over Rayleigh fading channels. We derive the general closed form expression of outage probability and asymptotic coding gain of the network.

SEP of Multihop Relay Networks in Nakagami-m Fading Channels

Abstract: In this paper we analyze the error performance of a cooperative multihop parallel relay network over Nakagami-m fading channels using M-ary Phase-shift keying (MPSK) modulation. We derive the general closed form expression of the symbol error probability (SEP) and present numerical results on the performance of the network.

A general performance model for MAC layer cooperative retransmission contention protocols

Abstract: Cooperative retransmission schemes can significantly improve transmission reliability and performance over high loss and time-varying links. However, analytically comparing performance between retransmission strategies is challenging and generally requires simplistic assumptions. This paper presents a general model for the performance of distributed, slot-based contention algorithms for opportunistic decode and forward retransmission algorithms. The model is independent of specific modulation or coding schemes and may be adapted to suit state-based transmission probability models. The model is validated through QualNet simulations.

An iteratively tuned fuzzy logic movement model in WSN using particle swarm optimization

Abstract: In contrast to adding new nodes, relocation of deployed nodes in mobile wireless sensor networks seems to be an effective solution to cope with undesirable, unpredictable and uncontrolled network topology changes due to nodes' drift and failure. At the price of less global control, there is a trend in recent years towards giving nodes more autonomy and devising localized relocation algorithms to address challenges of network topology control in harsh and hostile environments in the absence of centralized control. Inspired by laws of nature, a large variety of distributed node relocation algorithms have been designed to alleviate undesirable oscillations caused by local interactions and uncertainties among autonomous nodes as they reach their desired formations. Force-based distributed relocation algorithms governed by virtual push-pull forces among autonomous nodes are among such aforesaid algorithms. Adapting fuzzy logic model in exerting proper amount of forces to reduce node movement oscillation seems to be promising as its conforms well with uncertainties and interactions of autonomous nodes. However, parameters of fuzzy logic relocation model should be tuned so to enable nodes to exert proper amount of forces among their in-range neighbours. In this paper, by using particle swarm optimization, parameters of fuzzy relocation model are obtained based on the desired combinations of performance metrics within nodes' range in each movement iteration. The result shows that our model either outperforms or matches DSSA movement model.