Sharifah Hafizah Syed Ariffin

Performance Study of Wireless Body Area Network in Medical Environment

The advanced developments in sensors and wireless communications devices have enabled the design of miniature, cost-effective, and smart physiological sensor nodes. One of the approaches in developing wearable health monitoring systems is the emerging of wireless body area network (WBAN). IEEE 802.15.4 provides low power, low data rate wireless standard in relation to medical sensor body area networks. In the current study, the star network topology of 802.15.4 standard at 2.4 GHz had been considered for body area network (BAN) configured in beacon mode. The main consideration is in the total data bits received by all the nodes at the coordinator and flight times of a data packet reaching its destination. In this paper we discussed on wireless technologies that can be used for medical applications and how they perform in a healthcare environment. The low-rate Wireless Personnel Area Network (WPAN) is being used to evaluate its suitability in medical application.

A Survey of Existing Medium Access Control (MAC) for Underwater Wireless Sensor Network (UWSN)

Underwater wireless sensor networks (UWSN) consist of a certain number of sensors that interact to send the sensed data to the sink node and perform collaborative task. Most UWSN choose acoustic as a communication medium for wireless transmission. However, electromagnetic waves are also offer a great merit in special underwater environment such as shallow water. UWSN is significantly different from terrestrial sensor networks in many aspects such as mobility of sensor nodes due to water current, propagation delay and propagation loss. These distinctions feature of underwater sensor network pose many new challenges for delivering information from sensor nodes to sink node effectively in UWSN. To achieve reliable data transfer in underwater sensor network scenarios, a new event MAC protocol need to be developed to provide energy efficient and reliable upstream data transfer.

Proposed transport protocol for reliable data transfer in wireless sensor network (WSN)

Reliable data transport is one of the most important requirements in wireless sensor network where different applications have different reliability requirements. Additionally, the characteristic of wireless sensor network, especially dense deployment, limited processing ability, memory and power supply, provide unique design challenges at transport protocol. Therefore, assuring reliable data delivery between sensor nodes and the sink in Wireless Sensor Networks (WSN) is a challenging task. A reliable protocol in wireless sensor network is a protocol that allows data transfer reliably from source to destination with reasonable packet loss. The current issues of transport protocol are how to implement reliable data transport, congestion control and energy efficient. Most of the existing transport protocols only provide reliable data transport or congestion control. However, there are several protocols that provide both functions of the transport protocol. To overcome these issues, the transport layer protocols that provide both reliable data delivery and congestion control should be taken under consideration. Besides that, transport layer algorithm also allow maximum network lifetime due to limited operating lifetime of sensor node. Thus, to prolong the lifetime of wireless sensor network, an efficient transport protocol need to support reliable message delivery and provide congestion control in most energy efficient. This paper focuses on the existing transport protocols and the future protocol that provide the entire requirement of transport protocol.

Analyzing the Performance of Acoustic Channel in Underwater Wireless Sensor Network (UWSN)

Underwater acoustic wireless sensor networks (UAWSN) consist of a variable number of sensors that communicated with each other using acoustic signal and the sensor are deployed to perform collaborative monitoring tasks over a given area in underwater environment. The exploration in underwater environment will become crucial task in the future especially in oil/gas exploration. Designing underwater channel modeling for this type of network is essential and turns out to be a great challenged because of constrain and limitation in underwater environment. The unique characteristic of the underwater acoustic network are large propagation delay, limited bandwidth and high bit error rate. The goal of this paper is to analyze the performance of the acoustic channel in a Matlab simulation in term of sound speed and transmission loss.

User's mobility history-based mobility prediction in LTE femtocells network

Seamless and fast handover is one of main goals in Long Term Evolution (LTE) in supporting mobility and maintaining users quality of services. Mobility prediction is a technique to identify future targeted base station in advance, to reduce handover latency, and finally to enhance handover performance in wireless networks. In this paper, mobility prediction via Markov Chains with an input of users mobility history is proposed as a technique to predict the users movement in femtocells deployment. The results show that our proposed method predicts better when random data is 50% and above compared to the existing method. We had also analysed the effect of unavailable base station to the accuracy of the prediction in our proposed method. From the analysis, it is found that, the length of time collecting the data for the database effect the prediction accuracy in certain duration.

Accuracy Enhancement of Fingerprint Indoor Positioning System

There are several researches have been conducted and different methods have been applied to extend the features of indoor location tracking using wireless devices. Fingerprint algorithm is one of the popular methods that have been used to track mobile nodes in indoor structure. This paper focuses on the enrichment of positioning accuracy of the Fingerprint algorithm. RSSI mechanism has been used on the Fingerprint Algorithm to encompass better performance for the accurate positioning. The paper has been proposed two different types of Fingerprint methods and their performance variants on different circumstances of indoor environment. The proposed Fingerprint Database mapping has been divided according to the RSSI data redundancy. The proposed Fingerprint methods has been successfully implemented and experimented on UTMMIMOS CoE lab. The experimented results of two Fingerprint methods has been analyzed and compared as well.

An Indoor 3D Location Tracking System Using RSSI

Representation of indoor 3D location tracking had been an advantage to globally supported to track the mobile unit everywhere, even in different level of building. Our main focus is presenting development of indoor 3D location tracking to replace the existing 2D location tracking. The 2D location tracking mechanism only supports tracking the mobile unit position in the same level and provides handover or device switching. If the users need to go to another level, user will have to disconnect the connection. The development of the system that has a location tracking mechanism responsible to track the position of the mobile unit (such as laptop and PDA). In this paper, the system running in IPv4 framework and set up as a read test bed. The proposed location tracking will be based on Received Signal Strength Indicator (RSSI). The 3D location tracking system will be purely software based with minimum hardware dependent.

Biological inspired secure autonomous routing mechanism for wireless sensor networks

The field of wireless sensor network (WSN) is an important and challenging research area today. Advancements in sensor networks enable a wide range of environmental monitoring applications. Multihop routing in WSN is affected by new nodes constantly entering/leaving. Moreover, secure routing is a difficult problem due to the resource limitations in WSN. Thus, biological inspired algorithms are reviewed and enhanced to tackle the problems. Ant routing and human security system have shown excellent performance. Certain parameters as energy level, velocity, packet reception, dropping, mismatch rates and packet sending power are considered while making decision. The decision will come up with the optimal route and also to take best action against security attacks. In this paper, the design and initial work of BIOlogical Inspired Secure Autonomous Routing Protocol (BIOSARP) is presented. The proposed bio-inspired mechanism will meet the enhanced WSN requirements, including better delivery ratio, less energy consumption and routing overhead.

MPEG-4 video transmission using distributed TDMA MAC protocol over IEEE 802.15.4 wireless technology

The issues of green technology nowadays give an inspiration to the researcher to make all the future design to be energy efficient. Medium Access Control (MAC) layer is the most effective layer to provide energy efficient due to its ability to control the physical radio directly. One of the important applications in the future is a video transmission that can be transmitted with low-cost and low power consumption. MPEG-4 is one of the international standards for moving video. MPEG-4 provide better compression and primarily design at low bit rate communication. In order to achieve good quality for video application, the design at MAC layer must be strong. Therefore, to increase the performance of the MPEG-4 in IEEE 802.15.4, in this paper we propose a cross layer design between MAC layer and Application layer. A priority queue will be implemented at MAC scheduling depends on the level of frame important in MPEG-4 format frame. A distributed Time division Multiple Access (TDMA) will be used for MAC protocol to provide reliable data transmission for high priority frame.

Testbed design for Wireless Biomedical Sensor Network (WBSN) application

In wireless sensor network (WSN), a collection of nodes interacts with each other to gather information from the surveillance area. Some of the applications that WSN are currently being used are habitat monitoring, health care system and building automation, to name a few. Wireless Biomedical Sensor Network (WBSN) allows capturing of physiological signals, continuous monitoring and updating of a patients medical status remotely. This paper focuses on the development of a wireless sensor node testbed for WBSN application which complies with IEEE 802.15.4 standard and operates in 2.4 GHz ISM (industrial, scientific and medical) band. The initial state of WBSN development is the design of the wireless sensor node called TelG. The main features of TelG include low power consumption, wearable, flexible and small size. It is then embedded with a self-built operating system called WiseOS to support customized operations. A pulse oximeter is then integrated with TelG for the purpose of experimentation. The testbed performance is analyzed in terms of packet reception rate (PRR) and end-to-end delay. The results exhibit a decrease in PRR as distance increases and increasing network delay with increasing number of hops. It is also observed that received signal using the testbed is satisfactory for distances less than 10 meters per hop.