International Journal of Sensors Wireless Communications and Control - Volume 11, Issue 8, 2021

The employment of wireless body sensors for different applications like healthcare and transportation systems has been a key research area. The hybrid systems that combine the wearable wireless sensor technology for safety applications in transportation infrastructure to save the life of the drivers and Vulnerable Road Users (VRU) like cyclists and pedestrians is another step towards the aim of Intelligent Transportation Systems (ITS) to improve safety on roads. The systems in the literature involve the use of sensors fixed on or around the body of the driver and/or pedestrian, sensors embedded in smart devices like smartphone, smartwatch, and tablets, etc. to alert the drivers and pedestrians in advance to prevent the probability of collision and prevent road accidents. The sensors are able to detect the behavior of the driver and identify whether he/she is fit for driving a vehicle. The presence of a distracted pedestrian is another cause of the collision, and nearby vehicles should be informed about the same. In this paper, different systems in the literature that employ wireless body sensors to improve the safety of the commute have been reviewed. The techniques reviewed in this paper focus on the safety of the driver and VRU/pedestrian. The paper concludes by presenting key challenges and future research directions to prevent accidents by the integration of wireless body sensor networks as a part of an intelligent transportation system.

The Internet of Things (IoT) is one of the most emerging technologies, specially with the introduction of smart cities, smart homes, etc., anticipating fifty billion connected devices. IoT devices are usually limited in their processing, storage, and network bandwidth, and are more vulnerable to attacks that can be easily hacked and compromised. As IoT deals with personal life, so its security is one of the most critical challenges that need to resolve before its adoption. Distributed Ledger Technology (DLT), especially blockchain, is a relatively new technology that deals with the distributed immutable ledger. DLT is a promising technology that may solve the security issues of IoT. So a study needs to be done to know what security challenges of IoT can be solved using DLT and what are the ways in which DLT can be used to increase security. In this paper, first, we have set the research questions, then the systematic literature review has been done in view of research questions, then answers to research questions are presented, and discussion about the answers to research questions have been presented. A solution has been proposed that can be used to increase the security of IoT. Based on the review results, the paper concludes with the suggestions for using blockchain for IoT security.

Aim: This work evaluates the existing secure ant colony protocols of MANETs such as ASHFIK, AAMRP, and MANHSI with each other. Here, each node in the proposed ad hoc network protocols is known with a trust value. Each trust value represents the corresponding security level and a node with a higher trust value is authorized to monitor and lead its neighboring nodes as a core node. Background: Trusted critical MANET is a secure wireless network that is used in different critical applications. Military battlefields are an example of these applications that force on people a number of needed things, including robustness and reliable performance within high mobility situations and constraints (e.g. hostile attacks, cost, and battery limits). Objectives: In this work, the extremely important similarities between the features of critical MANETs and the core-based routing protocols that are based-on ant colonies are discussed. Methods: The metrics used in this evaluation are the availability, reliability, packet delivery ratio, and total overheads, while the performance is serious and stubborn because of the mobility of node, senders ' number, and size of a multicast group. Results: The results of the simulation show that ASHFIK provides better availability, reliability, Packet Delivery Ratio (PDR), and lower total overheads. In addition, the results show that ASHFIK has a consistent performance with a different group size of the network, which means that it is a trusted and scalable network of ant colony core-based routing protocols. Conclusion: Here, the existing different mobile ad hoc networks based-on ant colonies were discussed. According to our comparative study, the ASHFIK protocol can be used as a good routing protocol for critical MANETs that are based on ant colonies.

Background & Objective: The Orthogonal Frequency Division Multiplexing (OFDM) based large scale multiuser multiple input multiple output (LS-MU-MIMO) system is a preferred choice for signal transmission because it can substantially enhance the spectral and energy efficiency of the next-generation wireless systems. However, there are several practical issues in implementing large multiuser-MIMO-OFDM systems and one of the critical issues is the high Peak-to-Average- Power Ratio (PAPR). Due to the use of a large number of antennas at the Base Station (BS) of an LSMU- MIMO-OFDM system, it requires a large number of Power Amplifiers (PAs) which are needed to be connected to each antenna element. The high PAPR in an OFDM based LS-MU-MIMO system results in the decrease in the efficiency of PAs and enhancement in nonlinear signal distortions. This work is concerned with the reduction in PAPR of LS-MU-MIMO-OFDM systems using the SCFDMA scheme for the downlink transmission. The reduction in PAPR is achieved on the basis of discrete Fourier transform spreading (DFT-S) scheme known as DFT-SC-FDMA. The SC-FDMA scheme can achieve the reduction in PAPR of MIMO-OFDM signal up to the level of single-carrier transmission. Further, the reduction in PAPR is achieved with the sub mapping schemes such as localized FDMA (LFDMA) and distributed FDMA (DFDMA), Interleaved FDMA (IFDMA). Results: In this work, we propose to perform jointly multiuser MMSE precoding, SC-IFDMA and antenna reservation technique to reduce the PAPR and Bit Error Rate (BER) of the large MU-MIMO system. To show the effectiveness of the proposed scheme in the reduction of PAPR with different modulation techniques, subcarriers, and subcarrier mapping schemes, the results are compared with the existing OFDM based large MU-MIMO system. Conclusion: The MATLAB simulation results confirm that our proposed combination of MMSE MUprecoding, SC-IFDMA and antenna reservation technique is able to reduce PAPR and BER to a significant extent for LS-MU-MIMO-OFDM systems.

Background: The main requirement of Wireless Body Area Network (WBAN) is on-time delivery of vital signs that are sensed through the delay-sensitive biological sensors that are implanted in the body of the patient being monitored by the central gateway. The Medium Access Control (MAC) protocol standard IEEE 802.15.4 supports real-time data delivery through its unique feature called Guaranteed Time Slot (GTS) under its beacon-enabled mode. This protocol is considered suitable for the WBAN Scenario. However, as per the standard, IEEE 802.15.4 uses a simple and straightforward First Come First Served (FCFS) mechanism to distribute GTS slots among the contender nodes. This kind of blindfolded allocation of GTS slots results in poor utilization of bandwidth and also prevents the delay-sensitive sensor nodes from effectively utilizing the contention-free slots. Objective: The main objective of this work is to provide a solution for the unfair allocation of GTS slots in the beacon-enabled mode of the IEEE 802.15.4 standard in WBAN. Methods: We propose a Rational Allocation of Guaranteed Time Slot (RAGTS) protocol that distributes the available GTS slots based on the delay-sensitivity of the contender nodes. Results: A series of simulation experiments has been performed to assess the performance of our proposed RAGTS protocol. The simulations capture the dynamic nature of the real-time deadlines associated with sensor traffic. Through simulations, we show that our proposed RAGTS protocol appears to be more stable in terms of various performance metrics than that of the FCFS nature of the GTS allocation technique. Conclusion: In this article, we introduced the RAGTS scheme that enhances the real-time traffic feature of the beacon-enabled mode of IEEE 802.15.4 MAC.

Background: Monitoring the quality of potable water is a challenging endeavor due to the significant sources of contaminants, the majority of which are human-induced. Limited access to drinking water owing to acceleration in industrialization, urbanization in consort with growing inhabitants, unprocessed sewage discharge, and toxic industrial effluents causes different life-threatening diseases. Manual water quality monitoring techniques vividly aggravate quality deterioration. Considering the significance of the automatic water quality monitoring system, we need an in-situ, real-time, continuous surveillance system to ascertain the quality of potable water. Wireless Sensor Network (WSN) motivated us for a practical water quality monitoring system due to their continuous, real-time, and adaptive infrastructure to provide an early alert in hazardous conditions. Objective: To design and implement an online potable water quality monitoring network for rural water supply schemes in Nagapattinam district, Tamilnadu, India, to sense physiochemical parameters of potable water such as pH, turbidity, conductivity and temperature. Methods: Online POTable water quality monitoring NETwork (POTNET) integrates the reimbursements of WSN and different information and communication technologies for data acquisition, data processing, and data visualization. The core hardware of POTNET contains off-the-shelf sensors (i.e., electrodes), a microcontroller, a data transmission system, a customized buoyage, and a sink node. It senses physiochemical parameters of potable water such as pH, turbidity, conductivity, and temperature in a pre-programmed time interval. Furthermore, it enables cloud storage for gathered information and generates an alert to the preregistered user via mobile phones when there is a deviation of quality measures from threshold values. Results: The system was implemented in three overhead tanks for seven days in order to validate the stability of the buoy and efficiency of energy source, storage, and data transmission. It senses physiochemical parameters of potable water such as pH, turbidity, conductivity, and temperature in its predefined interval of 30 minutes. To check the system accuracy, the measured data values from developed sensors were compared with the observed data values using a commercial multi-parameter water checker, the Horiba® probe. Measured data were sent through the transceivers to the base station for data logging in a suitable format for ease of data visualization and utilization. Conclusion: Extensive experimental results reveal that our POTNET can be employed for potable water quality surveillance to help consumers or concern authorities to make a sound decision by providing appropriate and real-time data.

Achieve high throughput 128 bits FPGA based Advanced Encryption Standard. Background: Field Programmable Gate Array (FPGA) provides an efficient platform for design an AES cryptography system. It provides the capability to control each bit using HDL programming language such as VHDL and Verilog which results from an output speed in Gbps rang. Objective: Use Field Programmable Gate Array (FPGA) to design high throughput 128 bits FPGA based Advanced Encryption Standard. Method: Pipelining technique has been used to achieve the maximum possible speed. The level of pipelining includes round pipelining and internal component pipelining where a number of registers are inserted in particular places to increase the output speed. The proposed design uses combinatorial logic to implement the byte substitution. The s-box was implemented using composed field arithmetic with 7 stages of pipelining to reduce the combinatorial logic level. The presented model has been implemented using VHDL in Xilinx ISETM 14.4 design tool. Result: The achieved results were 18.55 Gbps at a clock frequency of 144.96 MHz and an area of 1568 Slices in Spartan3 xc3s1000 hardware. Conclusion: The results show that the proposed design reaches a high throughput with acceptable area usage compared with other designs in the literature.