Multi-hop Transmission Scheme Research Articles

An End-to-End IP Header Compressed Packet Forwarding Framework for Bandwidth-Constrained Networks

IP header compression technologies such as Robust Header Compression (ROHC) are well-known to improve bandwidth efficiency strategy using resource-constrained communication links. However, ROHC is a point-to-point approach so it must be maintained by the per-flow and per-hop, which is disadvantageous for bandwidth constrained networks (BCNs) featured by multi-hops transmission. In order to solve this problem, an efficient end-to-end IP header compressed packet forwarding framework for BCNs is proposed in this paper. Firstly, an end-to-end ROHC tunnel is established through the multi-hop transmission scheme. Then, based on the offer/answer model, a fast negotiation mechanism is established to ensure the context identifier (CID) is globally unique. Finally, the intermediate forwarder determines the next hop forwarding path according to CID. Therefore, besides reducing the transmission bandwidth and time consumption of compression and decompression per hop, it can also speed up forwarding the packets among BCNs. The simulation results show that the proposed framework improves forwarding efficiency and reduces end-to-end delivery latency and node power consumption in a BCN, which is independent of the channel conditions and the bit error rate.

Performance analysis of multihop wireless systems with decode and forward relays over Fisher– Snedecor F fading channels

ABSTRACT By reducing the transmitting power at the base station and expanding the coverage range of wireless communication, cooperative communication has turned into a higher imperative. This article evaluates the outage probability, average symbol error rate (ASER) for coherent as well as noncoherent modulation pattern, ergodic capacity and throughput of a multihop communication technique over the Fisher–Snedecor F fading channels. The multihop transmission scheme utilises a source, a set of relays and the destination node. The intervening relays of the system are regenerative with decode and forward type. Each hop of the system undergoes Fisher–Snedecor F fading channels. The MGF-based approach is used to derive the ASER of the system. The outage probability and ASER performance upgrade with the advancement of fading parameter as well as shadowing parameter of the channel. The ergodic capacity decreases with the improvement in shadowing parameter and the number of hops. The throughput of the system rises in connection with the reduction of total hops. Simulations validate the correctness of the numerically appraised results.

LEMH: Low-Energy-First Electoral Multipath Alternating Multihop Routing Algorithm for Wireless Sensor Networks

Lifetime is a vital performance metric for wireless sensor networks (WSNs), with current hierarchical routing protocols suffering from the premature death of overloaded nodes, affecting the network’s lifetime. Spurred by this problem, we propose a low-energy first electoral multipath alternating multihop (LEMH) routing scheme. To avoid overloading the nodes, these are given a contention radius that adaptively changes with the topology and affords the nodes to combine the remaining energy to vote for those participating in the cluster heads election process. Then, the running nodes decide the final cluster head based on two-dimensional competition parameters. Finally, the traditional multihop communication shortcomings are addressed by formulating an energy balance lifetime maximization routing problem based on sequential quadratic programming (SQP) under alternating multihop. This problem is optimally solved using particle swarm optimization (PSO), providing an improved multihop transmission scheme for WSNs. The simulation results demonstrate that LEMH effectively extends the network’s survival time and improves performance.

Probabilistic cooperative coded forwarding for broadcast transmissions in industrial mobile edge communications

Mobile edge computing (MEC) is considered as a key enabler for the industrial internet of things (IIoT) to cope with the ever-increasing communication and computing demands of nodes. In consideration of the limited resource of the IIoT nodes, it is necessary to design cost-effective multi-hop data transmission schemes for mobile edge IIoTs. However, most of the traditional schemes have to spend enormous cost to meet the reliability requirement, which cannot support timely information processing of MEC-based IIoT. In this article, the probabilistic cooperative coded forwarding (PCCF) scheme for multi-hop data transmission in mobile edge IIoTs is proposed to address the above problem. First, the data packets are encoded at a source IIoT node using the systematic sparse network coding (SSNC) mechanism, then the source broadcasts the coded packets to its one-hop neighbors. To minimize the required number of redundant coded packets, the sparsity of coded packets is optimized. Second, the nodes which received the packets will become volunteer relay nodes and forward the coded packets using the cooperative coded forwarding (CCF) mechanism. The volunteer relays first forward the received coded packets with a forwarding probability, and then re-encode a pair of received coded packets and broadcast the re-encoded packet with a re-encoding probability. To guarantee the broadcast performance while minimizing the transmission number at relay nodes, the feasible forwarding and re-encoding probability are provided. Third, the receiver nodes will try to decode the received coded and re-encoded packets and recover data packets without sending acknowledgments. Finally, through a series of experiments, we verify the accuracy of analytical approximations and also find out the optimal sparsity of coded packets and the existence of minimum transmission numbers. These provide insights for further optimization of multi-hop data transmission in mobile edge IIoTs.

A novel and unified approach for averaged channel capacity and averaged effective capacity analyses of diversity combining and multihop transmission schemes in flat fading environments

n this paper, we introduce an Lp -norm aggregation to present a signal-to-noise ratio expression unified not only for such diversity combining schemes as equal-gain combining, maximal-ratio combining, and selection combining, but also for such transmission techniques as multihop transmission. Accordingly, we propose two moment-generating function-based approaches that both respectively unify the exact analyses of the averaged channel capacity and averaged effective capacity over generalized fading channels with respect to the diversity combining and multihop transmission schemes. Finally, the mathematical formalism is illustrated by numerical special cases and verified by simulations.

생존시간 증대를 위한 협력적 에너지 하베스팅 기반 무선 멀티홉 전송 방식

IoT 환경에서는 배터리로 구동되는 무선 단말들이 멀티홉으로 연결되어 서로 상호작용을 하면서 서비스를 제공하기 때문에 멀티홉 환경에서의 효과적인 에너지 하베스팅 및 전송 기법이 필요하다. 본 논문에서는 멀티홉 기반의 선형 네트워크 토폴로지에서 노드간 협력을 이용한 에너지 하베스팅 기반 멀티홉 전송 방식을 제안한다. 에너지 하베스팅의 사용 유무와 노드간 협력 유무에 따라 멀티홉 전송 시스템을 수학적으로 모델링 하고, 협력적 에너지 하베스팅 기반 멀티홉 통신 프로토콜을 제안한다. 제안 프로토콜은 멀티홉 경로의 생존시간의 최대화를 목적으로 트레이드오프 관계를 갖는 멀티홉 노드의 생존시간을 동일하게 맞추어 주도록 노드별 에너지 전송 시간을 결정한다. 각 노드의 생존시간을 동일하게 만들기 위하여 새 떼가 동일 속도로 날아다니는 행동양식을 모방한 flocking 알고리즘을 적용하여 노드의 생존시간을 지역적으로 분산 평균화 시킨다. 시뮬레이션을 통하여 제안 알고리즘이 각 노드의 생존시간을 모두 동일하게 만들어 전체 경로의 생존시간을 최대화할 수 있음을 보여준다.

A Stratification-Based Data Collection Scheme in Underwater Acoustic Sensor Networks

Underwater acoustic sensor networks (UASNs) are widely used in a variety of ocean applications, such as exploring ocean resources or monitoring abnormal ocean environments. However, data collection schemes in UASNs are significantly different from those in wireless sensor networks due to high power consumption, severe propagation delay, and so on. Furthermore, previous research has overlooked practical conditions, such as characteristics of water delamination and energy constraint on autonomous underwater vehicles (AUVs). In this paper, a stratification-based data collection scheme for three-dimensional UASNs is proposed to solve these problems. In this scheme, the network is divided into two layers on the basis of the Ekman drift current model. The upper layer, called the Ekman layer, suffers large water velocity. Thus, nodes in the upper layer will follow the water flow. In this case, we employ a forward set-based multihop forwarding algorithm for data collection. The lower layer suffers small water velocity so that nodes in this layer are considered as relatively static. A neighbor density clustering-based AUV data gathering algorithm is applied in this layer for data collection. By employing different data collection algorithms in different layers, we can integrate the advantages of a multihop transmission scheme and AUV-aided data collection scheme to reduce network consumption and improve network lifetime. The simulation results also confirm the proposed method has good performance.

Relay Selection Scheme for Multi-Hop Transmission of MU-MIMO System

Recently, wireless communication systems use a multi-hop transmission scheme using a relay to expand the cell coverage of the system. The multi-hop transmission scheme can expand the cell coverage of wireless communication systems. However, if an appropriate relay is not selected, errors generated during signal processing in the relay are transmitted to the receiver. Therefore, a relay selection scheme is essential for reliable multi-hop transmission. This paper proposes a relay selection scheme for reliable multi-hop transmission in a multi user-multiple input multiple output (MU-MIMO) system. The proposed relay selection scheme uses a MIMO channel matrix between the transmitter and relays to select an appropriate relay. The proposed relay selection scheme obtains the singular values of the MIMO channel matrix using the singular value decomposition (SVD). Then, the sum of the singular values is calculated, and the relay having the largest value is selected. Therefore, in the proposed relay selection scheme, although the transmitter only knows the channel information between the transmitter and relays, the transmitter can select an appropriate relay for reliable multi-hop transmission.

Fuzzy Logic-Based Clustering Algorithm for Multi-hop Wireless Sensor Networks

To prolong the life of wireless sensor networks(WSNs) and reduce energy consumption, a clustering protocol based on fuzzy logic for Multi-hop WSNs(FLCMN) is proposed. The algorithm considers the residual energy of nodes, the number of neighbor nodes and the average residual energy of neighbor nodes. According to the pre-set fuzzy rule base, the fuzzy system is used to evaluate the satisfaction of the elected cluster head(CH). In addition, the average residual energy of neighbor nodes is taken into consideration, which improves the hotspot problem and balances the energy consumption between clusters. At the same time, in order to improve the hot issues among clusters, a multi-hop transmission scheme based on Fibonacci sequence is proposed to prolong the lifetime of the network. Through simulation, FLCAMN algorithm outperforms LEACH, EAMMH and DFLC algorithms in terms of network’s survival time and energy consumption.

Primary behaviour‐based energy harvesting multihop cognitive radio network

In this study, a multihop transmission scheme in cognitive environment is investigated. Several number of decode and forward relays are deployed between the secondary source and the secondary destination. All the nodes harvest energy using a time splitting-based relaying scheme from radio-frequency signal of a primary beacon (PB). All the nodes use harvested energy to transmit data from a node to its next node. The maximum transmit power of any secondary node is limited by interference constraint at a primary receiver. The presence of PB is considered in the form of a regular periodic pattern. An expression for signal-to-noise ratio and ergodic capacity at each secondary node in the multihop network are derived. A closed form expression for the outage probability (OP) of the secondary network is derived for transient and steady-state condition in two different scenarios of arrival time period of PB (). The closed-form expression for the OP of the secondary network is validated with the simulation results for different system parameters such as harvesting efficiency, harvesting time, the number of SRs, the transmission power of PB. An optimum value of the presence duration of PB within the time period is also estimated. Further, impact of imperfect channel state information (CSI) of interfering links between secondary transmitting nodes and primary receiver is investigated on secondary OP and compared with the case of perfect CSI.

The computation and analysis of energy‐efficient multirelay and multihop communication scheme in wireless sensor networks

SummaryWireless sensor network (WSN) has been one of the most important network technologies nowadays. However, the communication of wireless sensor nodes is often constrained by computation capability and energy efficiency, and direct transmission is hard to adapt to all communication environments. Cooperative transmission can achieve the low energy consumption requirements effectively. But most researches considered multirelay and singular‐hop scheme, and their energy efficiencies were not satisfactory in a longer transmission distance. To address this problem, we investigate the effect of the relay links and the relay node hops on the energy consumption in this paper. By deriving the outage probability of the multirelay and multihop transmission scheme, the minimum transmitting power of the source node is obtained. Then the existence of the minimum energy consumption is proved with respect to the number of relay links. Simultaneously, to reduce the computational complexity to ensure the effective implementation of the communication, the optimal number of relay links is calculated based on the minimum energy consumption. The simulation results show that the proposed multirelay and multihop transmission scheme has better transmission efficiency and can achieve satisfactory performance of communication and computation cooperation.

Secure Connectivity Probability of Multi-hop Clustered Randomize-and-Forward Networks

This work investigates secure cluster-aided multi-hop randomize-and-forward networks. We present a hop-by-hop multi-hop transmission scheme with relay selection, which evaluates for each cluster the relays that can securely receive the message. We propose an analytical model to derive the secure connectivity probability (SCP) of the hop-by-hop transmission scheme. For comparison, we also analyze SCPs of traditional end-to-end transmission schemes with two relay-selection policies. We perform simulations, and our analytical results verify that the proposed hop-by-hop scheme is superior to end-to-end schemes, especially with a large number of hops or high eavesdropper channel quality. Numerical results also show that the proposed hop-by-hop scheme achieves near-optimal performance in terms of the SCP.

A Cooperative Multihop Transmission Scheme for Two-Way Amplify-and-Forward Relay Networks

In this paper, we present a cooperative multihop transmission scheme for two-way amplify-and-forward (AF) relay networks. Based on a symbol error probability (SEP) analysis and using geographic information, we derive the maximum one-hop distance for a networking node under a given SEP and develop a next-hopping-node selection scheme. With these results, we then propose a routing protocol based on a greedy algorithm to realize the transmission scheme, where a routing path consisting of a number of independent two-way AF relaying procedures is built to connect the two sources. As compared to a previous related work, the proposed approach removes the utilization limitation and improves the routing efficiency. Computer simulation results also show that it provides a higher probability of successfully building a routing path with close effective throughput for most cases of interest.

Energy balancing zone-based cluster head approach to avoid energy hole problem in wireless sensor network

In wireless sensor network, the nodes near the sink will act as relay nodes, which carry heavy traffic compared to other nodes in the network. Due to this imbalance load communication, the nodes near to the sink will lose energy faster that leads to an energy hole problem. In this paper, we propose an energy balancing zone-based cluster head (EBZNCH) approach in which conical clustering area is divided into concentric rings called coronas. Each corona is further divided into equal zones of non-uniform distribution of nodes called homogenous clusters. A mathematical model is designed to maintain homogenous clusters of the same area by deriving a relationship between the width of the concentric rings and a mixed routing with load balancing strategy, which is used to balance the transmission energy of CHs. The simulation result demonstrates that the proposed scheme outperforms many existing cluster head rotation schemes such as HEED, LEACH, EBCAG and multihop transmission schemes.

Highly Efficient Multi-Hop Packet Transmission Using Intra-Flow Interference Cancellation and Maximal-Ratio Combining

Conventional Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA) multi-hop transmission suffers severely from intra-flow interference (IFI) in dense traffic, due to the hidden terminal (HT) problem. We propose a non-CSMA/CA multi-hop transmission scheme with IFI-canceler (IFIC) that can efficiently relay packets under high traffic loads in fading environments. This interference cancellation technique employs adaptive equalization with a normalized least mean square (NLMS) algorithm for channel estimation and has good BER/PER performance under a wide range of SNR and SIR conditions. It is also capable of canceling multiple interference sources. A multi-hop packet transmission frame format dedicated to the IFIC proposal is designed. An analysis model is created that considers possible outage events in multi-hop traffic flows. Simulations of multi-hop transmission indicate that IFIC throughput under slow Rayleigh fading linearly increases with traffic load and is 3.5 times higher than that of current CSMA/CA systems at the highest normalized traffic load. When 2-branch maximal-ratio combining (MRC) reception is added after IC, the throughput is further improved to a level very close to the theoretical maximum for additive white Gaussian noise (AWGN) channels. We also assess the impact of maximum Doppler frequency, and show that the best performance is maintained if the frequency is less than 10 Hz and the performance under higher Doppler frequencies can be effectively improved by retransmission.

Delay Characterization of Multihop Transmission in a Poisson Field of Interference

We evaluate the end-to-end delay of a multihop transmission scheme that includes a source, a number of relays, and a destination, in the presence of interferers located according to a Poisson point process. The medium access control (MAC) protocol considered is a combination of TDMA and ALOHA, according to which nodes located a certain number of hops apart are allowed to transmit with a certain probability. Based on an independent transmissions assumption, which decouples the queue evolutions, our analysis provides explicit expressions for the mean end-to-end delay and throughput, as well as scaling laws when the interferer density grows to infinity. If the source always has packets to transmit, we find that full spatial reuse, i.e., ALOHA, is asymptotically delay-optimal, but requires more hops than a TDMA-ALOHA protocol. The results of our analysis have applications in delay-minimizing joint MAC/routing algorithms for networks with randomly located nodes.We simulate a network where sources and relays form a Poisson point process, and each source assembles a route to its destination by selecting the relays closest to the optimal locations. We assess both theoretically and via simulation the sensitivity of the end-to-end delay with respect to imperfect relay placements and route crossings.

Extending Network Lifetime by Balancing Energy Consumption to Avoid Energy Hole Problem in WSN

In Wireless sensor network, for a hierarchical clustering the Cluster head near the sink will carry heavy traffic compared to other cluster heads present in the outermost level in the network. Due to this imbalance data communication, the cluster head near to sink will lose energy faster that leads to energy hole problem. In this paper, we propose an Energy Balancing Zone based Cluster Head (EBZCH) approach in which clustering area is divided into concentric rings called coronas. Each corona is further divided into equal zones called homogenous clusters. A mathematical model is designed to maintain homogenous clusters of same area by deriving a relationship between the width of the concentric rings and a mixed routing with proper data distribution strategy is used to balance the transmission energy of CHs. Simulation result demonstrates that the proposed scheme outperforms many existing schemes like direct transmission scheme, cluster head rotation schemes and multi hop transmission scheme

Efficient multihop transmission scheme for error-free relay forwarding in cooperative networks

Multihop cooperative communication is emerging as a key concept to extend the coverage area of the network and potentially increase the capacity. The spectral efficiency of such networks can be improved by adapting the transmission to time-varying channel conditions, referred to as incremental relaying. Although such incremental relaying concepts are progressively being studied, many challenges, such as erroneous transmissions by intermediate nodes and end-to-end delay of the network, limit its practical use due to lack of an efficient implementation. This paper proposes an efficient multihop incremental relaying technique. In this method, erroneous relay forwarding is mitigated, and the overhead for coordination among nodes is reduced by exploiting the implicit feedback channel available due to the broadcast nature of wireless transmissions. The proposed scheme fully leverages the benefit of overhearing and eliminates the additional feedback slots required for validation. Further, it ensures reliable forwarding of information, which optimizes the throughput of multihop networks. Thorough analysis of the proposed scheme is performed under different deployment environments, and the theoretical analyses presented in this paper are supported with results from extensive simulation studies. Copyright © 2013 John Wiley & Sons, Ltd.

Performance Analysis of Multihop-Diversity-Aided Multihop Links

A multihop transmission scheme is proposed and studied, where all the relay nodes (RNs) of a multihop link are assumed to have buffers for temporarily storing their received packets. Hence, the RNs are operated under the so-called store-and-forward relaying scheme. As a benefit of storing packets at the RNs, during each time slot, the best hop typically has the highest signal-to-noise ratio (SNR), which can be selected from the set of hops that have packets awaiting transmission in the buffer. A packet is then transmitted over the best hop. This hop selection procedure is reminiscent of selection diversity, which is referred to here as multihop diversity (MHD). In this paper, we investigate both the bit error and outage probability and the delay performance of the MHD scheme when assuming that each hop experiences both propagation path loss and independent and identically distributed (i.i.d.) flat Rayleigh fading. The medium access control (MAC) layer implementation and several closed-form formulas are derived. Both numerical and simulation results are provided to characterize the achievable performance of the MHD scheme. Our performance results show that relying on multiple hops has the potential to provide a significant diversity gain, which may be exploited for enhancing the reliability of wireless multihop communications.

A Multihop Transmission Scheme With Detect-and-Forward Protocol and Network Coding in Two-Way Relay Fading Channels

In this paper, we propose and analyze a multihop transmission scheme based on detect-and-forward (DF) relay protocol and network coding (NC) for two-way relay channels. In this scheme, the odd relays perform hard detection and then forward the detected signals to the next hop, whereas the even relays perform NC on the detected signals from the two adjacent nodes and broadcast them to the next hop. By separating the network into multiple two-hop subsystems, we develop closed-form expressions for bit error rate (BER) in flat Rayleigh fading channels. Our results are given as both lower bound and asymptotic expression based on an accurate upper bound of the end-to-end signal-to-noise ratio (SNR). It is shown that the proposed scheme has the same asymptotic BER performance and a much higher throughput compared with the conventional bidirectional relay scheme based on four transmission phases. Therefore, the proposed scheme is efficient for practical wireless applications. Simulation results are provided to validate the analysis.