International Journal of Sensors Wireless Communications and Control - Volume 11, Issue 2, 2021

Background and Objective: Piezoelectric energy harvesting is an emergent research area for unobtrusive power supply for fully autonomous micro-scale devices. Methods: The method of energy harvesting is to utilize waste ambient mechanical vibrations to generate electrical energy through the piezoelectric effect. Results and Conclusion: The present work highlights the major advances made in the field of micro- electromechanical systems based on piezoelectric energy harvester on extracting ambient vibrations and converting them into usable electric power. The present study explores energy harvesting approaches for portable electronics and self-powered wireless network nodes. The performance matrices like device physics, volume, operating frequencies, design and materials have been thoroughly analyzed in this work. Conventional cantilever fabrication steps have also been discussed. Finally, guidelines for future research and performance enhancements in the field of Piezoelectric Energy Harvesting (PEH) at micro scale have been discussed.

Background & Objective: The circular slotted monopole microstrip antenna with Coplanar Waveguide (CPW) feed for unified GSM and Ultra-Wideband (UWB) applications have been presented in this article. Circular shaped slots have been embedded in the radiating patch. Less surface area has been found due to slots etching and the overall antenna size is reduced by 45%. Results: The proposed antenna demonstrates a double band operation wrapping 883.6-1206 MHz (GSM band) and 2.75-18.30 GHz (UWB, X, and Ku) frequency band with VSWR of less than 2 and fractional B. W. of 30.8 % and 147% respectively. The pattern of radiation presented by the antenna is nearly omnidirectional in H-plane and directional in E-plane within the GSM and UWB band. Conclusion: There is a variety of applications nowadays using these UWB antennas such as modern civil and military applications, wireless and radar communications, etc. Measured results are presented to validate the proposed antenna structure, which shows that the proposed designed antenna structure has a stable radiation pattern both at the GSM and UWB band ranges.

Background: Systems-on-chips (SoCs) used by smart phones processor manufacturing companies such as Intel, Microsoft, Texas Samsung, etc, is an essential part of any mobile device. “Network-on-Chip” is used to integrate huge numbers of Intellectual Property (IP) blocks on a single Integrated Chip (IC). Different network topologies may be used in an NoC network, but mesh topology is widely used. In a conventional mesh structure, a defined router is implemented at every node in the structure. After analyzing various parameters such as delay, power, area of conventional mesh topology, we learned that it can be refined further. In this paper, a new 4x4 mesh topology structure is proposed, in which a combination of two different NoC router architecture is implemented in a single 4x4 mesh structure. Methods: Proposed 4x4 mesh structure consists of one conventional router and a new proposed router which is designed in such a way that it can only transfer its input data into two output channel. To achieve this component of the router such as Crossbar switch, buffer units of each channel are changed. This new proposed router Architecture model is simulated in Xilinx ISE 9.2i with targeted device Virtex4. Results & Conclusion: Based on comparative analysis with the conventional router, there is a significant 17.24 % reduction in the area of proposed 4X4 mesh structure as compared to conventional 4X4 Mesh architecture. Further, the same analysis was also performed for 8x8, 16x16, and 32x32 mesh structures.

Background: Barrier Coverage in Wireless Sensors Networks has been an active research area. Maximizing number of barriers formed after initial random deployment depends on deployment strategies used. Methods: Where existing works rely on sensor relocation after initial random deployment to maximize barrier coverage, authors in this article proposed a novel Minimum Radius Algorithm (MRA), a first of its kind where no two nodes, will be deployed within the non-overlap radius (OR). Results: The simulation results of the proposed algorithm proves that, MRA outperforms its counterpart not only in the case of maximizing barrier count but also in case convergence time required by network to form barriers. Extensive simulations are carried for all network sizes to show the effectiveness of proposed algorithm. Conclusions: This work aims at proposing a pre- deployment strategy that can maximize number of barriers.

Background & Objective: The healthcare applications provide the use of the wireless sensor network and wireless transmission of the physiological data of the patient due to the lack of medical facility. The wireless transmission can be caused due to some losses during the exchange of information. Various techniques are introduced in recent years to overcome these losses. Methods: For the efficient transmission requirements of the biomedical data, various techniques are introduced by different authors. This paper presents a review on the various transmission losses and techniques, in order to overcome these losses in the biomedical field. The authors also provide a comparison of the available transmission techniques and the need for real-time transmission. Results: The different physiological data of the patients is collected by using different medical sensors, which can create congestion, transmission delay and packet loss during transmission. The paper discusses the different congestion avoidance techniques to overcome the transmission loss like transmission delay, packet loss, network load, etc. which provide the minimum error rate during transmission. Conclusion: The healthcare application overcomes the difficulties that occur in the medical field with the use of wireless transmission and wireless sensor networks. The medical sensors collect a vast number of data, which can lead to congestion and other transmission losses in the network. It can affect the receiver's side for detecting the condition. To overcome these problems, different techniques like LACAS, Event to Sink Protocol, Relaxation Theory, etc. are introduced in recent years to enhance network performance.

Starting from the early 2000s, the concept of Smart City emerged as a new paradigm for urban development, driven by the exponential progress in communication and information technology as well as by the needs of a constant growing population. The Smart City context requires flexible infrastructures and processes, capable of reacting proactively depending on the situation. In this paper, we seek to explore the role of model-based predictive control (MPC) in the development of Smart Cities. The applications of MPC in different scenarios proves that this optimal control strategy is well suited for the dynamic environment in which it operates. Nevertheless, the literature review reveals that real life implementation of MPC as a control strategy within urban setting is still limited and further work is needed to facilitate its adoption in a wider context

For wireless communication networks, massive MIMO (Multiple-Input Multiple- Output) technology has been considered a major achievement. MIMO Technology consists of equipping a base station with a large number of antennas to serve many active users. Through MIMO Technology, the ability to concentrate on transmitted signal energy in very short spaces would result in huge increases in system capacity. While this new concept provides some fascinating benefits, it creates a new tension that has drawn both academia and industry attention. Channel state information acquisition, channel feedback, instant reciprocity, statistical reciprocity, architecture and hardware impairments are few of them. This paper presents a survey on Spatially Modulated Massive MIMO's historical development.

Background & Objective: In this article, a nano-cell coupled 2D photonic crystal waveguide bio- detection platform is proposed for the detection of organic liquids such as water, ethanol, glycerol, benzene and bromine for different refractive indices (n). Methods: The detection characteristics are analyzed and obtained for the band diagram, before and after change of radius (r) as well as after the injection of liquids into the heart of the nanostructure cell at the resonant wavelength (λ res). Also, we extracted variations from the power flow norm (P) to the resonance and the transmission (T) for each material. This nanostructure for different (n) materials used, gives (P) at different levels to the resonance. This explains the importance of the refractive index parameter (n) which plays a crucial role in the detection of materials. Results & Conclusion: The proposed biosensor enables the detection of liquids. This is shown through the numerical results obtained. These results give a good observation of the different behavior of the signal in the presence of the liquids used which depend on their refractive indices 'n'. This parameter 'n' is very important for detection when it varies from material to material. The proposed biosensor can be used in several research areas, particularly in medical and environmental applications.

Background: The privacy enabled IPv6 addressing mechanism ensures the privacy of the node's identification in the communication messages. It makes it difficult for adversaries to track nodes and link any activities with the node's IP or the MAC address. Scalability of the privacy enabled IPv6 addressing scheme for 6LoWPAN may be affected due to underlying MAC layer mechanisms. Objective: Hence, this study aims to explore such an impact. Methods: Addressing scheme is implemented in the Contiki operating system which uses duty cycling at the MAC layer along with the CSMA channel access mechanism. ContikiMAC and CXMAC are widely used duty cycling protocols in Contiki. An analytical study is presented in this paper, which analyses the IPv6 address configuration delay with ContikiMAC and CXMAC. Simulation is performed to corroborate the presented analytical model. The address configuration latency limits the scalability of the network. Hence, this paper studies the impact of duty cycling of the nodes on the address configuration latency and estimates the size of a single hop PAN. Results & Conclusion: It is observed that the ContikiMAC duty cycling protocol can achieve better performance compared to the CXMAC protocol in terms of address configuration latency. In order to make up for the delay due to duty cycling, the network can be divided into multiple PANs of smaller sizes where the addressing process runs simultaneously.

Background and Objective: In the Wireless Body Area Network (WBAN), sensors are placed on the human body, which has various mobility patterns like seating, walking, standing and running. This mobility typically assisted with hand and leg movements on which most of the sensors are mounted. Previous studies were largely focused on simulations of WBAN mobility without focusing much on hand and leg movements. Thus for realistic studies on the performance of the WBAN, it is important to consider hand and leg movements. Thus, objective of this paper is to investigate an effect of the mobility patterns with hand movements on the throughput of the WBAN. Methods: The IEEE 802.15.6 requirements are considered for WBAN design. The WBAN with star topology is used to connect three sensors and a hub. Three types of mobility viz. standing, walking and running with backward and forward hand movements is designed for simulation purpose. The throughput analysis is carried out with the three sets of simulations with standing, walking and running conditions with the speed of 0 m/s, 0.5 m/s and 3 m/s, respectively. The data rate was increased from 250 Kb to 10000 Kb with AODV protocol. It is intended to investigate the effect of the hand movements and the mobility conditions on the throughput. Simulation results are analyzed with the aid of descriptive statistics. A comparative analysis between the simulated model and a mathematical model is also introduced to get more insight into the data. Results: Simulation studies showed that as the data rate is increased, throughput is also increased for all mobility conditions; however, this increasing trend was discontinuous. In the standing (static) position, the throughput is found to be higher than the mobility (dynamic) condition. It is found that the throughput is better in the running condition than the walking condition. The average values of the throughput, in case of the standing condition, were more than that of the dynamic conditions. To validate these results, a mathematical model is created. In the mathematical model, the same trend is observed. Conclusion: Overall, it is concluded that the throughput is decreased due to the mobility of the WBAN. It is understood that mathematical models have given more insight into the simulation data and confirmed the negative effect of the mobility conditions on throughput. In the future, it is proposed to investigate the effect of interference on the designed network and compare the results.

Background: Cloud-Integrated Wireless Optical Broadband (CIW) access networks inheriting advantages of cloud computing, wireless and optical access networks have a broad prospect in the future. Objectives: Due to failure of components like OLT level, ONU level, link or path failure and cloud component level in CIW, survivability is becoming one of the important issues. Methods: In this paper, we have presented cloud-integrated wireless-optical broadband access network with survivability using Integer Linear Programming (ILP) model, to minimize the number of cloud components while providing maximum backup paths. Hence, we have proposed protection through cloud-integrated wireless router to available ONUs (PCIWRAO). Results: So, evaluated the backup path computation. We have considered ONU level failure in which the affected traffic is transferred through wireless routers and cloud component to the available ONUs using Manhattan distance algorithm. Conclusion: Simulation results show different configurations for different number of routers and cloud components illustrating available backup path when ONU fails.

Background: Cognitive radio can be described as a radio system where it familiarizes to the situations of the environs by some procedure like analyzing, observing and learning. Cognitive radio can basically recycle the unused white space in the license spectrum through sensing the network thus the method can achieve the maximum implementation of the radio bandwidth. Objective: The motivation of this research is to improve the performance of spectrum sensing of a group of users in every cluster where various channel environment will be presented in comparison with the conventional weighted sensing. Methods: With the intention of lessening the fading and shadowing, co-operative detection is favored over independent detection. Clustered based cooperation has been employed to expand the sensing enactment moderately. Sensing of co-operative spectrum which is weighted has been used to boost the cluster cooperation scheme. To crack the critical problem this research proposed a weighted cluster based co-operative sensing in which the weight calculation is performed at FC reducing all available redundancies. Results: From the simulation it is found that our proposed algorithm has better probability of detection (i.e, at -6 dB of SNR, clustered, Weighted Clustered and Novel Weighted Clustered probability of detections are 67%,84% and 95% respectively). Even if Novel Weighted Clustered has the lower False Alarm probability. Conclusion: Proposed novel weighted co-operative spectrum sensing algorithm for cognitive radio network spectrum sensing scheme can attain better performance under different fading environments.