Mahmood Ashraf Khan

HEER: Hybrid Energy Efficient Reactive protocol for Wireless Sensor Networks

Wireless Sensor Networks (WSNs) consist of numerous sensors which send sensed data to base station. Energy conservation is an important issue for sensor nodes as they have limited power. Many routing protocols have been proposed earlier for energy efficiency of both homogeneous and heterogeneous environments. We can prolong our stability and network lifetime by reducing our energy consumption. In this research paper, we propose a protocol designed for the characteristics of a reactive homogeneous WSNs, HEER (Hybrid Energy Efficient Reactive) protocol. In HEER, Cluster Head(CH) selection is based on the ratio of residual energy of node and average energy of network. Moreover, to conserve more energy, we introduce Hard Threshold (HT) and Soft Threshold (ST). Finally, simulations show that our protocol has not only prolonged the network lifetime but also significantly increased stability period.

Simulation Analysis of IEEE 802.15.4 Non-beacon Mode at Varying Data Rates

IEEE 802.15.4 standard is designed for low power and low data rate applications with high reliability. It operates in beacon enable and non-beacon enable modes. In this work, we analyze delay, throughput, load, and end-to-end delay of non-beacon enable mode. Analysis of these parameters are performed at varying data rates. Evaluation of non beacon enabled mode is done in a 10 node network. We limit our analysis to non beacon or unslotted version because, it performs better than other. Protocol performance is examined by changing different Medium Access Control (MAC) parameters. We consider a full size MAC packet with payload size of 114 bytes. In this paper we show that maximum throughput and lowest delay is achieved at highest data rate.

Telecom sector of Pakistan

Cellular subscribers teledensity and broadband growth of Pakistan in the last decade.FDI, telecom investment and revenue generation in Pakistan during the last decade.Challenges related to future telecom progress in Pakistan.Business opportunities and recommendations for future telecom growth.Impact of 3G/4G services on social and corporate sectors. Pakistan has exercised major developments recently in the Telecom sector. The main focus is to extend maximum benefits to the general user in terms of having accessibility to the modern services and better quality of service as a result of competitive environment amongst the network operators. The international investors also have directly contributed towards the economy as a result of which further horizons for exploring and improving the broadband market have emerged. In this paper, we have presented the growing telecom access and statistics, investment opportunities in the sector, modern applications and the broadband developments in line with the changing orientation of the telecom industry of Pakistan.

Modeling mobility and psychological stress based human postural changes in wireless body area networks

Proposed model gives mobility behavior of human body in WBAN.5 different postures of human body (i.e. standing, walking, running, sitting and laying).Posture transition according to markov model.Proposed model shows different mobility behavior in each posture.Mobility model is implemented in 2 routing schemes and 9 performance parameters. Mobility models play a vital role on the performance accuracy of simulations in Wireless Body Area Networks (WBANs). In this article, we propose a mobility model for the movement of nodes according to the posture patterns formed either because of psychological stress or any kind of mobility. During routine activities, body exhibits different postures like, standing, sitting, laying, etc. We form a mathematical model for the movement of nodes according to the posture pattern. In walking and running postures, the nodes placed on the limbs move in a defined trajectory repeatedly. In these postures, the nodes placed on trunk of the body are minimally mobile. On the other hand, in sitting and laying positions, the movement of limbs is nondeterministic. However, we can locate an area in which the nodes presence is most probable. Postures change from one state to another depending upon probabilities. During movement, the distance between nodes and sink is changed. As energy consumption, delay, and path loss depend on distance, so they also change due to mobility. We implement the proposed mobility model in multi-hop and forwarder based routing techniques. In multi-hop routing technique, nodes send data to the sink using neighboring nodes. Whereas, in forwarders based scheme, two forwarders are selected in each round to transmit, alongwith their own data, the received data of neighboring nodes. Simulation results show that forwarder based routing schemes has increased stability period, network lifetime and throughput.

Towards LP modeling for maximizing throughput and minimizing routing delay in proactive protocols in Wireless Multi-hop Networks

Wireless Multi-hop Networks (WMhNs) provide users with the facility to communicate while moving with whatever the node speed, the node density and the number of traffic flows they want, without any unwanted delay and/or disruption. This paper contributes Linear Programming models (LP_models) for WMhNs. In WMhNs, different routing protocols are used to facilitate users demand(s). To practically examine constraints of respective LP_models over different routing techniques, we select three proactive routing protocols; Destination Sequence Distance Vector (DSDV), Fish-eye State Routing (FSR) and Optimized Link State Routing (OLSR). These protocols are simulated in two important scenarios regarding to user demands; mobilities and different network flows. To evaluate the performance, we further relate the protocols strategy effects on respective constraints in selected network scenarios.

Peak Load Scheduling in Smart Grid Communication Environment

In this paper, we consider an Energy Consumption Scheduler (ECS) unit inside a smart meter. The function of ECS is to flatten the peaks in the load curve of residential type users. The ECS dually communicates with the user as well as power utility in smart grid real time communication environment. Each user has a specific power capacity limit for their appliances operation. The ECS keeps check and balance condition whenever a user exceeds its power capacity limit. Also the most urgent appliance operations are given priority based on their internalpreemption state. By adopting ECS unit, the total peaks in the load curve are reduced up to 33.3%. Also the users payment to the power utility becomes less due to efficiently managing their appliance operations. Additionally, the cost of per unit energy generation is also reduced by avoiding the peak power plants. Matlab/Simulink is used as a simulation tool for the realization of this model.

Design of a Low-cost Underwater Wireless Sensor Network for Water Quality Monitoring

Abstract With the ongoing advancements in the field of wireless technologies and sensor networking, a lot of research is taking place in using such sensor networks for multitude monitoring situations, e.g. home, office monitoring systems, body area sensor networks, and environmental monitoring systems. These systems cost a lot and are complicated as in operating. Thus, our main goal is the development of low-cost, yet effective sensor networks for monitoring the quality of water bodies like lakes, water reservoirs, ponds, etc., Such systems would be deployed in a lake, a small reservoir, etc., which would relay back the real-time values of different parameters like pH, turbidity, temperature, etc., to the monitoring station wirelessly in an efficient and cost-effective manner.

Robust stabilization of underactuated nonlinear systems: A fast terminal sliding mode approach

This paper presents a fast terminal sliding mode based control design strategy for a class of uncertain underactuated nonlinear systems. Strategically, this development encompasses those electro-mechanical underactuated systems which can be transformed into the so-called regular form. The novelty of the proposed technique lies in the hierarchical development of a fast terminal sliding attractor design for the considered class. Having established sliding mode along the designed manifold, the close loop dynamics become finite time stable which, consequently, result in high precision. In addition, the adverse effects of the chattering phenomenon are reduced via strong reachability condition and the robustness of the system against uncertainties is confirmed theoretically. A simulation as well as experimental study of an inverted pendulum is presented to demonstrate the applicability of the proposed technique.

Design and Development of a Low Cost Ubiquitous Tracking System

Abstract In this paper, design and development of a ubiquitous tracking system is proposed, in which vehicles are tracked and controlled using the prevailing cellular technologies. The system contains a GPS receiver and a GSM modem interfaced with a microcontroller. To track any vehicle, the vehicles owner has to send an SMS to the tracking system installed inside the vehicle. Upon receiving the SMS, the microcontroller takes the current locations longitude and latitude coordinates from GPS receiver, packs it into an SMS and sends it to the owner and on a web server using GSM modem. When the web server receives the SMS containing vehicles coordinates, it will show location of the vehicle on Google Maps. For android users, the location is also displayed on an android application. In case of vehicle theft, the owner is able to turn off the main ignition switch, check status and speed of the vehicle simply by sending an SMS. The system is also equipped with a special security button for parked vehicles. By turning the button ON, the system will come in ACTIVE mode and will keep a special check on the vehicles movement meanwhile performing the normal tasks. If the system senses any movement of vehicle during the ACTIVE mode, it will turn the main ignition OFF and will inform the owner immediately be sending 5 SMSs. Record of the vehicles movement will be continuously managed on the web server where each owner will have vehicles account. We have used a wide number of technologies including, but not limited to, Global Positioning System (GPS), Global System for Mobile Communication (GSM) and Microcontroller.

Transmission Delay of Multi-hop Heterogeneous Networks for Medical Applications

Nowadays, with increase in ageing population, Health care market keeps growing. There is a need for monitoring of Health issues. Body Area Network consists of wireless sensors attached on or inside human body for monitoring vital Health related problems e.g, Electro Cardiogram (ECG), ElectroEncephalogram (EEG), ElectronyStagmography(ENG) etc. Data is recorded by sensors and is sent towards Health care center. Due to life threatening situations, timely sending of data is essential. For data to reach Health care center, there must be a proper way of sending data through reliable connection and with minimum delay. In this paper transmission delay of different paths, through which data is sent from sensor to Health care center over heterogeneous multi-hop wireless channel is analyzed. Data of medical related diseases is sent through three different paths. In all three paths, data from sensors first reaches ZigBee, which is the common link in all three paths. After ZigBee there are three available networks, through which data is sent. Wireless Local Area Network (WLAN), Worldwide Interoperability for Microwave Access (WiMAX), Universal Mobile Telecommunication System (UMTS) are connected with ZigBee. Each network (WLAN, WiMAX, UMTS) is setup according to environmental conditions, suitability of device and availability of structure for that device. Data from these networks is sent to IP-Cloud, which is further connected to Health care center. Main aim of this paper is to calculate delay of each link in each path over multihop wireless channel.