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MANET is an infrastructure-less, fixed topology less, multi-hop and bandwidth constraint wireless network. In MANET optimized control message broadcasting through an efficient routing can results in bandwidth utilization and efficient data transmission with minimum numbers of hops. An efficient routing technique using a broadcast network, designed by existing minimum cost spanning tree (MCST) is also unable to provide all-nodes-to-all shortest route and also have issues about data transmission efficiency. In this article, our broadcast network design approaches can provide a solution for optimized control message broadcast and data transmission efficiency by considering Kruskalś MCST based broadcast network as a base network. Initially, we consider high-frequency links (HF-Link) to be added in the base network by considering the Dijkstra algorithm. Secondly, the broadcast network is designed by including those links with the neighbors who have at least a fixed number of neighbors (CF-Link) and finally, only those links are added with the base network which gives a shorter path to all other nodes (ST-Link) in the network. Using Omnet++ we have compared individual broadcast network design with the base network and observe that a slight increment in control overhead in existing based techniques could increase data efficiency significantly through a given suboptimal path.

The enhanced Mobile Broadband (eMBB) and ultra-Reliable Low Latency Communications (uRLLC) are the two main scenarios of $5^{th}$ generation (5G) mobile communication system networks. There is an obvious difference in service requirements between different scenarios. When multi-scenario services coexist in the 5G networks, exploring optimized resource scheduling and allocation strategies become a critical issue. The 5G New Radio (NR) and numerology technologies have been standardized, which lay the foundation for flexible frame structure and adaptive scheduling. In this paper, we propose the self-adaptive flexible transmission time interval (TTI) scheduling (SAFE-TS) strategy in the eMBB and uRLLC coexistence scenario. Machine learning (ML) is applied to achieve flexible TTI scheduling. Moreover, we design the random forest-based ensemble TTI decision algorithm (RF-ETDA) to accomplish the TTI selection for each service. Compared with the existing ML methods, the proposed algorithm has a performance improvement in selecting TTI, especially for the uRLLC services. Then, the TTI selection results will be the basis of system resource scheduling and allocation. The simulation results prove that the proposed SAFE-TS effectively reduce the delay and packet loss rate of the uRLLC services while guaranteeing the eMBB requirements. Therefore, it is highly recommended that flexible TTI scheduling should be applied in the construction of the 5G networks to achieve superior network performances.

In wireless sensor networks (WSNs), providing source node with sink position is an essential principle for geographic routing protocols. Previous works have only focused on the problem of sink localization in a 2-D sensing field while that of 3-D WSNs has received little attention. Providing sink location service with low control overhead and energy consumption is a challenging issue in 3-D WSNs area. In this paper, we propose a unital design based sink location service (UDSL) for WSNs. In this scheme, sink location announcement (SLA) and sink location query (SLQ) packets are forwarded along two paths or blocks. The node located at the intersection of the two paths sends the sink position to the source. In the proposed method, SLA and SLQ messages are constructed using unital design blocks. For this purpose, a mapping from unital design to sink location service has been proposed. However, this basic mapping does not guarantee an intersection of paths,therefore, we propose an enhanced UDSL providing 100% probability of intersection. In order to analyze the proposed scheme’s performance, extensive WSNs simulations and experiments have been conducted. The results indicate that UDSL provides reasonable performance in terms of hop counts, path length, and energy consumption for providing sink location service.

The foremost challenge in designing Wireless Sensor Networks (WSNs) is careful node placement. Sensor Node placement is a one of the powerful optimization technique for accomplishing the anticipated goals. This paper focuses on categories of node deployment in WSN. The paper highlights various problems and identifies the different objectives in sensor node deployment. The paper proposes a novel node deployment strategy based on Quasi- random method of low-discrepancy sequences to increase the lifetime and the coverage of the network. The aim of the paper is to study how the node deployment affects the different QoS parameters such as packet delivery ratio, average energy consumption, delay, etc. with various multi-objective routing algorithms WSN. To validate the proposal simulation, results are presented in this paper. The paper concludes with the future outlook.

With the widespread use of IoT applications and the increasing trend in the number of connected smart devices, the concept of routing has become very challenging. In this regard, the IPv6 Routing Protocol for Low-power and Lossy Networks (PRL) was standardized to be adopted in IoT networks. Nevertheless, while mobile IoT domains have gained significant popularity in recent years, since RPL was fundamentally designed for stationary IoT applications, it could not well adjust with the dynamic fluctuations in mobile applications. While there have been a number of studies on tuning RPL for mobile IoT applications, but still there is a high demand for more efforts to reach a standard version of this protocol for such applications. Accordingly, in this survey, we try to conduct a precise and comprehensive experimental study on the impact of various mobility models on the performance of a mobility-aware RPL to help this process. In this regard, a complete and scrutinized survey of the mobility models has been presented to be able to fairly justify and compare the outcome results. A significant set of evaluations has been conducted via precise IoT simulation tools to monitor and compare the performance of the network and its IoT devices in mobile RPL-based IoT applications under the presence of different mobility models from different perspectives including power consumption, reliability, latency, and control packet overhead. This will pave the way for researchers in both academia and industry to be able to compare the impact of various mobility models on the functionality of RPL, and consequently to design and implement application-specific and even a standard version of this protocol, which is capable of being employed in mobile IoT applications.

An ad hoc wireless network consists of mobile networks which create an underlying architecture for communication without the help of traditional fixed-position routers. There are different protocols for handling the routing in the mobile environment. Routing protocols used in fixed infrastructure networks cannot be efficiently used for mobile ad-hoc networks (MANET), so it requires different protocols. The node moves at different speeds in an independent random form, connected by any number of wireless links, where each node is ready to pass or forward both data and control traffic unrelated to its own use ahead (routing) to other nodes in a flexible interdependence of wireless communication in between. In contrast to infrastructure wireless networks, where the communication between network nodes is take place by a special node known as an access point. It is also, in contrast to wired networks in which the routing task is performed by special and specific devices called routers and switches. In this paper, we consider fuzzy inference system, an attempt has been made to present a model using fuzzy logic approach to evaluate and compare three routing protocols i.e. AODV, DSDV and DSR using effective factor of the number of nodes based on 3 outputs of control overhead, delay and PDR (totally fuzzy system with 4 outputs) in order to select one of these two routing protocols properly under different conditions and based on need and goal. To show efficiency and truth of fuzzy system, three protocols have been evaluated equally using NS-2 simulator and attempt has been made to prove efficiency of the designed fuzzy system by comparing results of simulation of fuzzy system and NS-2 software.

In mobile ad hoc network, nodes co-operatively form a network independent of any fixed base station infrastructure. Every node in a mobile ad-hoc network can function as a router and forwards the data packets to the other nodes. Multicasting plays an important role whenever group communications are required. Most of the existing multicast routing protocols in mobile ad hoc networks consider only one source in a multicast group and become inefficient when the protocol is extended to multi-source multicasting. In this paper, we propose a unicast forwarded multi-source multicast routing protocol, for ad hoc networks which is having more than one source in a group. Here, the sources of the group also act as a receiver for other sources in that group. The proposed routing method is a cluster based one and avoids the flooding or broadcasting of control packets to form routing structure. On executing source joining and receiver joining procedures, a complete path for multicast data transfer was established. As the join request control packets are forwarded only through cluster-heads and junction nodes, lower amount of control overhead is incurred. Simulation result shows that the proposed protocol maintains the delivery ratio with reduced control overhead and utilizes the bandwidth efficiently.

The MAC layer will need to be significantly redesigned to support the highly directional transmissions, very low latencies and high peak rates featured in 5G millimeter wave communication. This paper analyzes the frame structure and beamforming choices for mmWave MAC layer design. In this work we illustrate simple analytical methods to quantify the resource utilization and physical layer control overhead for millimeter wave cellular systems. It is observed that certain flexible frame design choices may lead to dramatically improved resource utilization under various traffic patterns. Moreover, it is shown that fully digital beamforming architectures offer significantly lower overhead than analog and hybrid beamforming under comparable power budgets.

The millimeter-wave (mmWave) frequencies have attracted considerable attention for fifth generation (5G) cellular communication as they offer orders of magnitude greater bandwidth than current cellular systems. However, the medium access control (MAC) layer may need to be significantly redesigned to support the highly directional transmissions, ultra-low latencies and high peak rates expected in mmWave communication. To address these challenges, we present a novel mmWave MAC layer frame structure with a number of enhancements including flexible, highly granular transmission times, dynamic control signal locations, extended messaging and ability to efficiently multiplex directional control signals. Analytic formulae are derived for the utilization and control overhead as a function of control periodicity, number of users, traffic statistics, signal-to-noise ratio and antenna gains. Importantly, the analysis can incorporate various front-end MIMO capability assumptions -- a critical feature of mmWave. Under realistic system and traffic assumptions, the analysis reveals that the proposed flexible frame structure design offers significant benefits over designs with fixed frame structures similar to current 4G long-term evolution (LTE). It is also shown that fully digital beamforming architectures offer significantly lower overhead compared to analog and hybrid beamforming under equivalent power budgets., Comment: Submitted to IEEE Transactions for Wireless Communications

The host-multi-SIMD chip multiprocessor (CMP) architecture has been proved to be an efficient architecture for high performance signal processing which explores both task level parallelism by multi-core processing and data level parallelism by SIMD processors. Different from the cache-based memory subsystem in most general purpose processors, this architecture uses on-chip scratchpad memory (SPM) as processor local data buffer and allows software to explicitly control the data movements in the memory hierarchy. This SPM-based solution is more efficient for predictable signal processing in embedded systems where data access patterns are known at design time. The predictable performance is especially important for real time signal processing. According to Amdahl¡¯s law, the nonparallelizable part of an algorithm has critical impact on the overall performance. Implementing an algorithm in a parallel platform usually produces control and communication overhead which is not parallelizable. This paper presents the architectural support in an embedded multiprocessor platform to maximally reduce the parallel processing overhead. The effectiveness of these architecture designs in boosting parallel performance is evaluated by an implementation example of 64x64 complex matrix multiplication. The result shows that the parallel processing overhead is reduced from 369% to 28%. ePUMA

Providing real-time voice support over multihop ad hoc wireless networks (AWNs) is a challenging task. The standard retransmission-based strategies proposed in the literature are poorly matched to voice applications because of timeliness and large overheads involved in transmitting small-sized voice packets. To make a voice application feasible over AWNs, the perceived voice quality must be improved while not significantly increasing the packet overhead. We suggest packet-level media-dependent adaptive forward error correction (FEC) at the application layer in tandem with multipath transport for improving the voice quality. Since adaptive FEC masks packet losses in the network, at the medium access control (MAC) layer, we avoid retransmissions (hence, no acknowledgments) in order to reduce the control overhead and end-to-end delay. Further, we exploit the combined strengths of layered coding and multiple description (MD) coding for supporting error-resilient voice communication in AWNs. We propose an efficient packetlzation scheme in which the important substream of the voice stream is protected adaptively with FEC depending on the loss rate present In the network and is transmitted over two maximally node-disjoint paths. The less Important substream of the voice stream is encoded into two descriptions, which are then transmitted over two maximally node-disjoint paths. The performance of our scheme (packet-level media-dependent adaptive FEC scheme) is evaluated In terms of two parameters: residual packet loss rate (RPLR, packet loss rate after FEC recovery) and average burst length (ABL, average length of consecutive packet losses after FEC recovery) of voice data after FEC recovery. The sets of equations leading to the analytical formulation of both RPLR and ABL are first given for a renewal error process. The values of both these parameters depend on FEC-Offset (r, the distance between original voice frame and piggybacked redundant voice frame) and loss rate present in the network. Then, these parameters are computed for a Gilbert-Elliott (GE) two-state Markov error model and compared with experimental data. Our scheme adaptively selects the FEC-Offset (it chooses 7' that minimizes RPLR and ABL as much as possible) based on the loss rate feedback obtained from the destination. The proposed scheme achieves significant gains in terms of reduced frame loss rate (FLR), reduced control overhead, and minimum end-to-end delay and almost doubles the perceived voice quality compared to the existing approaches. � 2008 IEEE.