Journal of High Speed Networks - Volume 25, issue 2

Authors: Ren, Keqiang | Wu, Mingkang

Article Type: Research Article

Abstract: In order to improve the localization accuracy of unknown nodes in DV-Hop algorithm, an improved DV-Hop algorithm combined with adaptive hop count and optimized hop distance was proposed. Our proposed algorithm firstly introduced the concept of the adaptive value for the number of communication radii. It was used to adaptively select the number of communication radii for beacon nodes and could realize the subdivision of the minimum hop count. Secondly, sensor nodes adaptively set the hop threshold to reduce the calculation. Finally, the calculation method of the average hop distance of beacon nodes was optimized and the error was corrected. …The average hop distance of unknown nodes was obtained by the weighted normalization used for the average hop distance of beacon nodes. Simulation results in both random deployment environment of sensor nodes and nonrandom deployment environment of beacon nodes demonstrate that the localization accuracy of our proposed algorithm is significantly better than the DV-Hop algorithm and furthermore has better robustness and adaptability. Show more

Keywords: Wireless sensor networks, DV-Hop algorithm, adaptive, average hop distance, weighted average

DOI: 10.3233/JHS-190607

Citation: Journal of High Speed Networks, vol. 25, no. 2, pp. 127-137, 2019

Authors: Verma, Poonam | Singh, Neeta

Article Type: Research Article

Abstract: This paper proposes a two-tier structure for improving the MAC layer performance of a vehicular network. In tier-1, an improved vehicle-ID based analytical model is proposed. In tier-2, a fuzzy-based computational system named FUZZ-CCS is designed for controlling congestion in the vehicular network. Initially, the paper considers a fundamental element of the vehicular network, namely that each CAM generated by a vehicle is associated with a unique ID. Using this property, every vehicle weighs the random backoff number chosen by them in the back-off process, with the vehicle ID incorporated in their respective CAMs, eventually leading to the selection of …a distinctive random back-off number. The vehicle ID based Markov model is validated through MATLAB. Further, in tier-2, collision probability (obtained from the proposed analytical model) and vehicular density are considered as input for designing the FUZZ-CCS. CAM broadcast rate is considered as the adapting parameter for controlling congestion throughout the network. Obtained simulation results show that the proposed FUZZ-CCS outperforms the fixed CAM rate IEEE 802.11p in terms of collision probability. Show more

Keywords: FUZZ-CCS, congestion control, vehicle-ID, random back-off number, contention window, collision probability

DOI: 10.3233/JHS-190608

Citation: Journal of High Speed Networks, vol. 25, no. 2, pp. 139-153, 2019

Authors: Sadi, Mustapha | Amad, Mourad | Badache, Nadjib

Article Type: Research Article

Abstract: Group Communication System (GCS) is largely recognized as fundamental support in fault tolerance solutions. The need for such a system arises not only in wired networks but also in mobile Ad-Hoc networks. The design of this service becomes more complex in these networks because of their very dynamic topology and limited energy autonomy. Group Membership service is considered as a significant part of the GCS . In this paper, we propose HiCo-MoG (Hierarchical Consensus for Mobile Group) : an efficient solution for group membership in large mobile Ad-Hoc Network (MANET) . While the group membership problem is also equivalent …to Consensus, we use the Dynamic Hierarchical Consensus called (HCD) with dynamic clusterheads set for designing a group membership service for MANETs . The HCD protocol achieves consensus using the clusters provided by a new failure detector called ◇ C . Each group member can obtain a consistent view of the group by executing the consensus protocol. We demonstrate the efficiency of our method in term of scalability and fault tolerance. Show more

Keywords: Group communication system, group membership, hierarchical consensus, MANETs, HiCo-MoG

DOI: 10.3233/JHS-190609

Citation: Journal of High Speed Networks, vol. 25, no. 2, pp. 155-172, 2019

Authors: Li, Yanli | Wang, Xiaonan | Dou, Zhengxiong

Article Type: Research Article

Abstract: Technological advancements make the Internet of Vehicles (IoV) become reality so that vehicles can access a variety of multimedia data from the Internet. The IoV is a multi-hop network and employs the Internet protocol to acquire multimedia data from the Internet. Since the size of multimedia data is large, it is extremely significant to reduce the data acquisition latency in the IoV. In this paper, we focus on the data acquisition issue in the multi-hop IoV and propose a new data acquisition solution to reduce the data acquisition latency. The main idea of our solution is to employ the single-hop …k -anycast model to achieve the data acquisition in the multi-hop IoV. To make the idea work, we propose a multi-address mechanism in order to acquire different data chunks from different optimal k -anycast servers in parallel. The data acquisition latency is quantitatively evaluated. According to the experimental results, our solution substantially reduces the data acquisition latency compared with the existing approach. Show more

Keywords: Internet of vehicles, multi-hop, k-anycast, data acquisition, multi-address

DOI: 10.3233/JHS-190610

Citation: Journal of High Speed Networks, vol. 25, no. 2, pp. 173-180, 2019

Authors: Radha, S. | Shylu, D.S. | Nagabushanam, P. | Mathew, Jisha

Article Type: Research Article

Abstract: Low Noise Amplifier (LNA) is the front end block in RF receiver that improves the performance of wideband receivers. These receivers need LNA with high linearity to protect its signals from out-of-band interferences. Linearization is a key factor in LNA that maintains linear operation in the presence of large distracting signals. Existing techniques in LNA design are optimum gate biasing, MGTR, body biasing, noise cancellation, feed forward, derivative superposition, and modified DS technique. The key challenge of RF LNA circuit is to attain high gain and better noise performance with low power consumption without affecting linearity of LNA. This paper …presents several linearization methods used in CMOS LNA. These are (1) post distortion, (2) capacitive feedback, (3) resistive feedback, and (4) current reuse technique. We also propose a new method for LNA with resistive and capacitive feedback. In this paper, different LNA circuits and proposed LNA are simulated using 90 nm CMOS technology. Reuse of bias current and two stage coupling by single current source approach in the proposed current reuse LNA with resistive (R) and capacitive (C) feedback yields better gain of 15.2 dB, noise figure of 2.17 dB and power consumption of 7.1 mW with respect to other techniques. The outputs obtained are compared with other similar works. These results validate that the proposed LNA is practically feasible for wireless sensor network applications. Show more

Keywords: Low noise amplifier (LNA), single ended LNA, resistive feedback, capacitive feedback, post distortion linearization technique (PD-LNA), current-reuse technique

DOI: 10.3233/JHS-190611

Citation: Journal of High Speed Networks, vol. 25, no. 2, pp. 181-203, 2019

Authors: Ningthoujam, Sanjit | Chakraborty, Swarnendu K.

Article Type: Research Article

Abstract: This paper presents the new throughput analysis of the adaptive three modes for Packet Combining (PC), Modified Packet Combining (MPC) and Aggressive Packet Combining (APC) techniques. The three modes in this paper consist of X (low probability of packet error), Y (moderate probability of packet error) and Z (high probability of packet error) channel states. The three states are based on the number of received acknowledgement (either positive acknowledgement (ACK) or negative acknowledgement (NACK)) by Transmitter (Tx). The PC, the hybrid PC+MPC and the hybrid MPC+APC techniques are implemented in X, Y and Z channel states respectively for enhancing the …fast error correction and also to reduce retransmission of duplicate copies. Thus, the proposed protocol is simulated using MATLAB and the results yield better performance over conventional PC, MPC and APC techniques in terms of throughput, the probability of packet error correction and energy consumption. Show more

Keywords: PC, MPC, APC, three states, bit error rate

DOI: 10.3233/JHS-190612

Citation: Journal of High Speed Networks, vol. 25, no. 2, pp. 205-220, 2019