Mohd Adib Sarijari

Energy detection sensing based on GNU radio and USRP: An analysis study

Cognitive radio wireless networks are an emerging communication paradigm to effectively address spectrum scarcity challenge. Spectrum sensing plays a paramount role in cognitive radio, which is widely agreed to be the most promising method for alleviating the symptom of RF spectral scarcity. Dynamic access of unused spectrum via a cognitive radio asks for flexible radio circuits that can work at an arbitrary radio frequency. In this paper, we analyze the performance of spectrum sensing on GNU Radio system with USRP. We investigating spectrum scarcity and proposed the algorithm that performed and measuring the energy of Rx signal in a fixed bandwidth, W, over an observation time window, T. The results presented that it can detected of primary user signal over the fixed bandwidth which occupied the spectrum.

Security system using biometric technology: Design and implementation of Voice Recognition System (VRS)

Biometric technology is fast gaining popularity as means of security measures to reduce cases of fraud and theft due to its use of physical characteristics and traits for the identification of individuals. The earliest methods of biometric identification included fingerprint and handwriting while more recent ones include iris/eye scan, face scan, voice print, and hand print. Biometric voice recognition and identification technology focuses on training the system to recognize an individualpsilas unique voice characteristics (i.e., their voice print). The technology lends itself well to a variety of uses and applications, including security access control for cell phones (to eliminate cell phone fraud), ATM manufacturers (to eliminate pin # fraud) and automobile manufacturers (to dramatically reduce theft and carjacking). In this paper, we present an implementation of a security system based on voice identification as the access control key. Verification algorithm is developed using MATLAB (SIMULINK) function blocks which is capable of authenticating a personpsilas identity by his or her voice pattern. A voice match will produce logic dasia1psila while a mismatch, logic dasia0psila. A microcontroller circuit controlling access to a door is built to test the reliability of this voice controlled security system. It is found out that the developed voice recognition software has successfully activated the door opening mechanism using a voice command that ONLY works for the authenticated individual. The system is proven to be able to provide medium-security access control and also has an adjustable security level setting to account for the variations in onepsilas voice each time a voice identification occurs.

Experimental study of OFDM implementation utilizing GNU Radio and USRP - SDR

A Software Defined Radio (SDR) is a radio which can tune to any frequency band, transmit and receive different modulations and different physical parameters across a large frequency spectrum by using a programmable hardware and powerful software. An SDR performs significant amounts of signal processing in a general purpose computer, or a reconfigurable piece of digital electronics or the combination of both. In this paper, we seek to explore the viability of using GNU Radio; an open source SDR implementation and the Universal Software Radio Peripheral (USRP); an SDR hardware platform, to transmit and receive the OFDM radio signal with QPSK and BPSK modulation. Quality of Service (QoS) in terms of Packet Received Ratio (PRR) on the data transmitted will then be investigated and analyzed.

Wireless Home Security and Automation System Utilizing ZigBee based Multi-hop Communication

Nowadays, smart home using wireless communication is replacing the wired system which was very messy and difficult to setup. However, the existing wireless smart home system only can cover up to a certain range of area that is limited by the range of wireless module being used. This paper introduces the conceptual understanding and strategy of ZigBee IEEE 802.15.4 standard to be deployed in smart home environment. ZigBee technology offers a multi-hop communication capability for data transfer. Multi-hop communication will provide unlimited range of communication for the system as long as there are intermediate nodes that will pass the data from one node to another until it reaches the destination. Prototype systems of home security and automation are built utilizing Zigbee based sensor network to present an insight for its practical implementation in smart home concept.

Home healthcare via wireless biomedical sensor network

Fast information retrieval is pivot of medical breakthrough to provide quality medical services. There were a number of attempts to develop clinical information system (CIS) which is reliable, affordable and accessible over the entire hospital and beyond. Todays home healthcare progression is becoming a predominant form of healthcare delivery. Although there have been many recent advances in biomedical sensors, low-power radio communication and embedded computation, there does not yet exist a flexible, robust communication infrastructure to integrate these devices into an emergency care setting. An efficient wireless communication substrate for medical devices that addresses ad hoc or fixed network formation, naming and discovery, security and authentication, as well as filtration and aggregation of vital sign data need to be studied. The potential applications will save lives, create valuable data for medical research, and cut the cost of medical services. In this paper, we focus on home healthcare via wireless sensor network (WSN) platform. WSN composed of a large number of sensor nodes and multi-hop networking capability that are densely deployed for a wide variety of applicants such as smart buildings, interactive user interfaces, environment control and highly suitable for monitoring in military and biomedical applications. We describe our experiences in developing and implement both hardware and software platform for medical sensor network, provides protocol for device discovery and multi-hop routing, as well as a simple query interface that is tailored for medical monitoring.

Experimental studies of the ZigBee frequency agility mechanism in home area networks

A normal home environment consists of various wireless technologies, in particular WiFi and ZigBee, which usually operate in the ISM 2.4-GHz band. In addition, some of the home appliances (e.g., a microwave oven) may operate in this crowded ISM band. WiFi-based, ZigBee-based devices and home appliances operating at the same frequency and physical space can cause harmful interference to one another, particularly to ZigBee technology. Therefore, the ZigBee Frequency Agility mechanism is introduced by the ZigBee Alliance to ZigBee networks for resolving such harmful interference. In this paper, we experimentally study the performance of the ZigBee Frequency Agility mechanism using a home area network (HAN) testbed. The measurement results show that this mechanism can effectively overcome interference caused by WiFi-based devices. However, in the extreme case, when all the channels are occupied, the mechanism is not effective as expected. In addition, it is observed that the response time for the ZigBee Frequency Agility mechanism to perform channel switching is depending on packet-error-rate (PER) and send-packet-counter thresholds. Low thresholds can reduce channel-switching time but increases signaling overhead. Thus, in order to obtain optimum performance, self-adaptive PER and send-packet-counter thresholds based on interference level are desired rather than static ones.

Design and implementation of Wireless Biomedical Sensor Networks for ECG home health monitoring

Sensor network, in the form of wireless biomedical sensor network (WBSN), composed of a number of biomedical sensor nodes and multihop networking capability that can be deployed for long term and continuous healthcare monitoring. Physiological signals (ECG, EEG etc) will be measured by the biosensors that provide alerts immediately when abnormalities in a patients physiological condition are detected. Development of wearable biomedical sensors within a wireless infrastructure opens up possibilities for smart home care by providing ubiquitous monitoring of patients under their physiological states even when they move, leading to better quality of patient care. In this paper, we describe the design and implementation of wireless biomedical sensor network (WBSN) node platform featuring a low-power CMOS 8-bit microcontroller, an IEEE 802.15.4 compatible transceiver and a compact ECG sensor that does not require skin preparation, gels, or adhesives. The developed platform is cost-effective and allows easy customization, energy-efficient computation and communication.

Flood transmission based protocol for home automation system via power line communication

There are many researches and development involving the use of power line as data transmission medium. With multiple power outlets in almost every room in every house, the power line is the most pervasive network and the largest infrastructure available. The aim of this project is to deploy this infrastructure in designing a home automation system. This paper presents a method to develop a home automation system using the AC (alternating current) power line to establish a network between main controlling unit and client units with a proprietary designed power line communication (PLC) protocol. The designed protocol has features such as multinode simplex communication, flood transmission and even parity error detection. The protocol is successfully implemented and tested in a home automation system consisting of one main controlling unit and three client units. Each client unit is able to control three electrical devices. Multipoint of receiver units can be controlled (on/off) by the main controller unit sending command data using power line as transmission medium to the corresponding devices.

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.

TDMA-based cooperative sensing using SDR platform for cognitive radio

The current trend and demand of wireless services requires more efficient spectrum usage. With Cognitive Radio (CR) technology, spectrum efficiency will be increased by exploiting unused licensed or primary users spectrum. Spectrum sensing mechanism is one of the main cores in CR system. To combat the problems of shadowing, multipath fading, and hidden nodes, cooperative spectrum sensing has been proposed. Testbed prototyping for sensing is a challenging task. The demand for cooperative sensing to solve the above mentioned problems leads to proposals of PHY and MAC layer solutions. Therefore, in this paper, we demonstrate an experimental platform using USRP board that can facilitate the development of PHY and MAC layers functionality for cooperative spectrum sensing. In this paper, TDMA-based MAC protocol for cooperative sensing mechanism is proposed. The observation of the preliminary experimental measurement shows significant performance in term of feasibility of cooperative decision mechanism in wireless condition.