Multihop Cellular Networks Research Articles

Device discovery for multihop cellular networks with its application in LTE

A multihop cellular network combines the benefits of both a fixed cellular infrastructure and the flexibility of an ad hoc network. However, one of the most challenging issues for a multihop cellular network is the need for proximate device discovery that enables the discovery of the network topology and the direct communications between proximate devices. This article first reviews the device discovery techniques used in most wireless ad hoc communication systems. We then address the unique issues of device discovery in a cellular network and potential solutions. We discuss the advantages and disadvantages of various discovery schemes. Finally, we present a discovery scheme in an LTE cellular network as a practical example to illustrate the design principles of device discovery under a unified cellular network-centric architecture.

Energy‐efficient opportunistic forwarding in multi‐hop cellular networks using device‐to‐device communications

AbstractCellular networks face significant capacity, efficiency and quality challenges because of the exponential growth of cellular data traffic. Multi‐hop cellular networks (MCNs) have been proposed to address these challenges through the integration of cellular and device‐to‐device communications. This work investigates how the adoption and design of opportunistic store, carry and forward mechanisms in MCNs can help importantly decrease the energy consumption for delay tolerant traffic. To this aim, the study first derives an analytical framework to identify in two‐hop scenarios the optimum mobile relay location and the location from which the mobile relay should start forwarding the information to the cellular base station in order to minimise the overall energy consumption. The derived optimum configuration is then used as a benchmark for the proposal and design of a novel context‐based opportunistic MCN forwarding scheme that exploits context information provided at low cost by the cellular network. Numerical and simulation results demonstrate that the proposed context‐based opportunistic forwarding can achieve a performance close to that obtain with the optimum configuration and reduce the energy consumption by more than 90% compared with traditional single‐hop cellular communications. Copyright © 2014 John Wiley & Sons, Ltd.

On the Capacity of Downlink Multi-Hop Heterogeneous Cellular Networks

Multi-hop heterogeneous cellular networks (MHCNs) consist of conventional macro cellular networks overlaid with an irregular deployment of low-power base stations (BSs), where the communication between BSs and mobile users can be established through a single hop or multiple hops. By modeling different kinds of randomly located BSs as K tiers of independent homogeneous Poisson Point Processes, we first explore the capacity of downlink MHCNs and derive the expression of capacity under Rayleigh fading channels. Particularly, the capacity gain achieved by cell splitting and multi-hop relaying is quantified for the first time. We then study the effects of BS density, transmit power, and signal-to-interference-plus-noise-ratio (SINR) threshold on the capacity of MHCNs. More importantly, we obtain the spectral efficiency enhancement condition under which the increase of BS density and transmit power improve the spectral efficiency, thereby enhancing the capacity. One interesting observation is that at a given SINR threshold, the capacity increases with BS density when all the tiers have the same SINR threshold. Moreover, the capacity of some special networks (i.e., heterogeneous cellular networks, multi-hop cellular networks, and conventional cellular networks) are derived directly by specializing some system parameters in our results. Finally, numerical studies and simulations are conducted to validate our analysis.

Joint Interference Coordination and Load Balancing for OFDMA Multihop Cellular Networks

Multihop cellular networks (MCNs) have drawn tremendous attention due to its high throughput and extensive coverage. However, there are still three issues not well addressed. With the existence of relay stations (RSs), how to efficiently allocate frequency resource to relay links becomes a challenging design issue. For mobile stations (MSs) near the cell edge, cochannel interference (CCI) become severe, which significantly affects the network performance. Furthermore, the unbalanced user distribution will result in traffic congestion and inability to guarantee quality of service (QoS). To address these problems, we propose a quantitative study on adaptive resource allocation schemes by jointly considering interference coordination (IC) and load balancing (LB) in MCNs. In this paper, we focus on the downlink of OFDMA-based MCNs with time division duplex (TDD) mode, and analyze the characteristics of resource allocation according to IEEE 802.16j/m specification. We also design a novel frequency reuse scheme to mitigate interference and maintain high spectral efficiency, and provide practical LB-based handover mechanisms which can evenly distribute the traffic and guarantee users' QoS. Our study shows that our scheme not only meets the requirement on coverage, but also improves the throughput while accommodating more users in MCNs.

멀티홉 셀룰러 네트워크에서 억제 및 우선순위 접속 제어기반의 이웃노드 탐색 프로토콜

In multihop cellular network environments, the mobility of nodes is a major obstacle to find a reliable routing path between a mobile node (MN) and the access node (AN). Therefore, in this paper, we propose a fast and reliable neighbor discovery protocol that enables the fast and reliable neighbor discovery by considering the node mobility in the multihop cellular network. The proposed neighbor discovery protocol inhibits the transmission of unnecessary control messages to quickly find a suitable neighbor node (NN) and performs a priority-based access control to transmit control messages without collision in the order of NN desirable to be selected. Simulation results show that the proposed neighbor discovery protocol can discover the NNs faster than the conventional scheme and select a more reliable relay node although the number of neighbor nodes increases and the node mobility increases.

IRRATIONAL NODE DETECTION IN MULTIHOP CELLULAR NETWORKS USING ACCOUNTING CENTER

In multihop cellular networks mobile nodes typicall y transmit packets during intermediate mobile nodes for enhancing recital. Stingy nodes typically don't collaborate that incorporates a negative result on the network fairness and reci tal. A fair, inexpensive and best incentive mechanism by Selfish Node Detection (FESC IMbySND) has been projected to stimulate the mobile node’s cooperation. Hashing operations area unit employed in order to e xtend the safety. Trivial Hash perform has been won t to improve end-to-end delay and outturn. Additionally Cyclic Redundancy Check M echanism has been used to spot the ridiculous nodes that involve themselves in sessions with the intention of dropping the in sequ ence packets. Moreover, to cut back the impact at t he Accounting Center a Border node has been commend the task of propose the check s employing a digital signature.

Performance Analysis of Malicious nodes on Multi hop Cellular Networks

The existence of malicious nodes in multi hop cellular networks, which operate without a central administration infrastructure, can result in performance degradation or even disruption of the network operation. In this paper we proposed some approaches to analysis the consequences caused by malicious nodes in networks. We analyzed and reported the simulation result, that the effect on performance of network when malicious node present in it. Based on our past report on the behavior of all nodes we will achieve higher levels of security and reliability by utilizing them. To reduce the public key cryptography operations we will use light weight hashing operations along with the routes between source and destination.The proposed model improves all the drawbacks of multi hop cellular networks, which excludes and if not possible, minimizes the number of malicious node in the routes.

Optimal Routing and Traffic Scheduling for Multihop Cellular Networks Using Genetic Algorithm

When considering a multicell scenario with nonuniform traffic distribution in multihop wireless networks, the search for the optimum topology becomes an NP-hard problem. For such problems, exact algorithms based on exhaustive search are only useful for small toy models, so heuristic algorithms such as genetic algorithms (GA) must be used in practice. For this purpose, we present a novel sequential genetic algorithm (SGA) to optimize the relaying topology in multihop cellular networks aware of the intercell interference and the spatial traffic distribution dynamics. We encode the topologies as a set of chromosomes and special crossover and mutation operations are proposed to search for the optimum topology. The performance is measured by a fitness function that includes the throughput, power consumption and delay. Improvement in the fitness function is sequentially controlled as newer generations evolve and whenever the improvement is sufficiently increased the current topology is updated by the new one having higher fitness. Numerical results show that SGA provides both high performance improvements in the system and fast convergence (at least one order of magnitude faster than exhaustive search) in a dynamic network environment. We also demonstrate the robustness of our algorithm to the initial state of the network.

Experimental evaluation of multihop cellular networks using mobile relays [Accepted From Open Call

Future wireless networks are expected to provide high bandwidth multimedia services in extended areas with homogeneous Quality of Service (QoS) levels. Conventional cellular architectures might not be able to satisfy these requirements due to the effect of surrounding obstacles and the signal attenuation with distance, in particular under Non Line of Sight (NLOS) propagation conditions. Recent studies have investigated the potential of Multi-hop Cellular Networks (MCNs) to overcome the traditional cellular architecture limitations through the integration of cellular and ad-hoc networking technologies. However, these studies are generally analytical or simulation-based. On the other hand, this paper reports the first experimental field tests that validate and quantify the benefits that MCNs using mobile relays can provide over traditional cellular systems.

Multi-hop Network Bandwidth Management Scheme Based on Cooperative Bargaining Models

Multi-hop cellular network (MCN) can preserve the advantages of traditional single-hop cellular networks and ad hoc relaying networks. In multi-hop network, efficient bandwidth management plays an important role in determining network performance. In this paper, a new bandwidth management scheme is proposed for MCNs. By integrating the Nash and Kalai---Smorodinsky bargaining models, the proposed scheme adaptively controls the wireless bandwidth to maximize network efficiency. In the proposed Nash and Kalai---Smorodinsky bargaining models, bargaining powers are decided according to the real-time negotiation process. It is a powerful method for resolving conflicts and enables the system to fairly and effectively control the bandwidth management problem. With a simulation study, it is demonstrated that the proposed scheme approximates an optimized solution under widely diverse traffic load intensities.

Multihop Cellular Networks: Dynamic Channel Assignment and Routing Protocol for Improving Performance

Multihop cellular Networks has the problem of channel assignment when connections are established between the adjacent cells and due to more number of nodes in the path between the sender and the receiver relay delay occurs and cause unwanted delay in the overall end to end communication. To overcome the problems associated with the relay delay and the overall performance in the Multihop Cellular Networks a new protocol is introduced which combines the merits of both the modified Minimum Slot Waiting First Algorithm and the modified Distance Vector Routing. Through the proposed new protocol, we can provide solution for the problem of routing and relay delay in Multihop Cellular Networks and the performance of the packet transmission can be improved.

Context-Aware Nanoscale Modeling of Multicast Multihop Cellular Networks

In this paper, we present a new approach to optimization of multicast in multihop cellular networks. We apply a hexagonal tessellation for inner partitioning of the cell into smaller subcells of radius r. Subcells may be several orders of magnitude smaller than, e.g., microcells, resulting in what we refer to as a nanoscale network model (NSNM), including a special nanoscale channel model (NSCM) for this application. For such tessellation, a spatial interleaving SI MAC protocol is introduced for context-aware interlink interference management. The directed flooding routing protocol (DFRP) and interflooding network coding (IFNC) are proposed for such a network model including intercell flooding coordination (ICFC) protocol to minimize the intercell interference. By adjusting the radius of the subcell r , we obtain different hopping ranges that directly affect the throughput, power consumption, and interference. With r as the optimization parameter, in this paper we jointly optimize scheduling, routing, and power control to obtain the optimum tradeoff between throughput, delay, and power consumption in multicast cellular networks. A set of numerical results demonstrates that the NSNM enables high-resolution optimization of the system and an effective use of the context awareness.

Mitigating location management traffic via aggregation in multi-hop cellular networks

In high mobility areas such as shopping malls and transportation stations, mobile users tend to move in and out in a bursty fashion, and hence location update (LU) and paging signaling cause substantial traffic burden to the cellular networks, leading to signaling congestion. This poses a great challenge to the system design for wireless cellular systems. Traditional cellular systems cannot cope with this situation very well. However, with the ad hoc operational mode recently introduced into the cellular systems, the added multi-hop relaying via mobile devices provides a new way to mitigate location management traffic. In this paper, based on this new architecture, we propose a novel scheme, called aggregative location management, which aggregates multiple location updates into group location updates. For the scenarios of high capacity transit (HCT) systems, we use this grouping scheme to alleviate the signaling traffic when mobile users in an HCT move into new location areas. For other scenarios with mass arrivals of LU requests, we develop a generic aggregative location management scheme in which LU requests can be first aggregated by designated mobile devices and then are periodically sent to the location registers. Performance evaluation is carried out and shows their significant effectiveness.

Multi Hop Secure Adhoc Network to Eradicate Cooperative Diversity

The concept of peer to peer mobile networks reflects on tactical network. This approach helps mobile nodes to scatter anywhere in the network and it also provide additional support for the MANET in terms of data distribution. This paper provides the result of such approach in terms of network cluster formation with secure node proximity within the boundary. This proximity paradigm will enhance the performance of network by avoid wide scattering of mobile nodes beyond the networks zone. The results shown in this paper were the work done in ns2 mobility package. The result also incorporates AODV routing protocol with IEEE 802.11 MAC for wireless network to improve network performance using mobile node proximity in conjunction with the previous work indicating the network performance degradation with these configuration. To device proximity among mobile nodes were done along with secure mechanism, such that every nodes data transmission was done only on the basis of IDS implementation with PSO fitness value. This will invoke security for every data transmission done on this network. This work has significant effect by improving network performance by 50%. Keywords: Multi Hop Cellular Network, Mobile Node Proximity, Tactical Mobile Network

Mobile-based relay selection schemes for multi-hop cellular networks

Multi-hop cellular networks (MCNs), which reduce the transmit power, mitigate the inter-cell interference, and improve the system performance, have been widely studied nowadays. The relay selection scheme is a key technique that achieves these advantages, and inappropriate relay selection causes frequent relay switchings, which deteriorates the overall performance. In this study, we analyze the conditions for relay switching in MCNs and obtain the expressions for the relay switching rate and relay activation time. Two mobile-based relay selection schemes are proposed on the basis of this analysis. These schemes select the relay node with the longest relay activation time and minimal relay switching rate through mobility prediction of the mobile node requiring relay and available relay nodes. We compare the system performances via simulation and analyze the impact of various parameters on the system performance. The results show that the two proposed schemes can obtain a lower relay switching rate and longer relay activation time when there is no reduction in the system throughput as compared with the existing schemes.

A Secure Mobile Payment Framework in MANET Environment

In this paper the authors propose a Secure Mobile Payment Framework in Multi hop Cellular Network environment (which is an integration of cellular networks and mobile ad hoc networks) using Mobile Agent technology and Digital Signature with Message Recovery (DSMR) mechanism based on ECDSA mechanism. Secure communication in Multi hop Cellular Networks is a nontrivial task because of lack of infrastructure, no prior trust relationships among nodes due to the absence of a centralized authority. Mobile Agent technology and Digital Signature with Message Recovery based on ECDSA mechanism provides secure mobile payments in Multi hop Cellular Networks. Mobile Agent technology has many benefits such as bandwidth conservation, reduction of latency, reduction of completion time, Asynchronous (disconnected) communications. Digital Signature with Message Recovery based on ECDSA eliminates the need of adopting PKI cryptosystems. The proposed protocol ensures Authentication, Integrity, Confidentiality and Non Repudiation, achieves Identity protection from merchant and Eavesdropper, achieves Transaction privacy from Eavesdropper and Payment Gateway, achieves Payment Secrecy, Order Secrecy, forward secrecy, prevents Double Spending, Overspending and Money laundering. The security properties of the proposed protocol have been verified successfully using BAN Logic, AVISPA and Scyther Tools and presented with results.

Enhanced Channel Assignment Algorithm for Relaying Nodes in W-CDMA Multihop Cellular Network

Enhanced Channel Assignment Algorithm for Relaying Nodes in W-CDMA Multihop Cellular Network

Reversed Stackelberg bandwidth-sharing game for cognitive multi-hop cellular networks

Multi-hop relaying cellular network (MCN) is a recently proposed architecture to preserve the advantages of traditional single-hop cellular networks and ad hoc relaying networks. In MCNs, efficient bandwidth management plays an important role in determining network performance. In this study, a new cognitive radio bandwidth-sharing scheme is proposed based on the reversed Stackelberg game model. In the proposed scheme, base station (BS) and relay stations (RSs) are hierarchically interconnected and interacting with one another to effectively share the wireless bandwidth. By using a trust model, the BS appropriately reacts to selfish RSs to maximise network performance. This approach can promote cooperation with respect to adaptive bandwidth allocation. With a simulation study, it is demonstrated that the proposed scheme can approximate an optimised solution under widely diverse traffic load intensities.

Inter-relay Handoff in two-hop relaying networks with highly mobile vehicles

In multihop cellular networks, mobile users can communicate with the base stations via relay stations (RSs), and handoff between different RSs. This type of handoffs is referred to as inter-relay handoffs. In networks with highly mobile users, the inter-relay handoffs can occur very frequently. Making intelligent inter-relay handoff decisions is important in order to improve the network performance. In this article, we study the inter-relay handoff decision problem in a two-hop cellular network with highly mobile vehicles using a semi-Markov decision process. The objective is to maximize the total reward, which is defined by taking into consideration the transmission rate of the user’s link, the overheads for performing inter-relay handoffs, and the moving speed of the user. Numerical results are shown to demonstrate the effectiveness of the handoff decisions.

Impact of Channel Partitioning and Relay Placement on Resource Allocation in OFDMA Cellular Networks

Tremendous growth in the demand for wireless applications such as streaming audio/videos, Skype and video games require high data rate irrespective of user’s location in the cellular network. However, the Quality of Service (QoS) of users degrades at the cell boundary. Relay enhanced multi-hop cellular network is one of the cost effective solution to improve the performance of cell edge users. Optimal deployment of Fixed Relay Nodes (FRNs) is essential to satisfy the QoS requirement of edge users. We propose new schemes for channel partitioning and FRN placement in cellular networks. Path-loss, Signal to Interference and Noise Ratio (SINR) experienced by users, and effects of shadowing have been considered. The analysis gives more emphasis on the cell-edge users (worst case scenario). The results show that these schemes achieve higher system performance in terms of spectral efficiency and also increase the user data rate at the cell edge.