A Review of UWB MAC Protocols

In this paper, we review several ultra-wideband (UWB) medium access control (MAC) protocols that have been proposed to date. This review then considers the possibility of developing an optimal MAC layer for high data rate UWB transmission systems that transmit very little power especially in application to mobile devices. MAC in UWB wireless networks is necessary to coordinate channel access among competing devices. Unique UWB characteristics offer great challenges and opportunities in effective UWB MAC design. We first present the background of UWB and the concept of MAC protocols for UWB. Secondly, we summarize four UWB MAC protocols that have been proposed by other researchers and finally, a conclusion with a view to the planned future work. The main contribution of this paper is that it presents a summarised version of several MAC protocols applicable to UWB systems. This will hopefully initiate further research and developments in UWB MAC protocol design

Finding the Optimal MAC Protocol for Low-Power High Data Rate Ultra-Wideband (UWB) Networks

In this paper, we explore the possibility of designing an optimal medium access control (MAC) layer for high data rate ultra-wideband (UWB) transmission systems that transmit very little power especially in mobile devices. MAC in UWB wireless networks is necessary to coordinate channel access among competing devices. The unique UWB characteristics offer great challenges and opportunities in effective UWB MAC design. We first study the background of UWB and available MAC protocols that have been used in UWB. Secondly, we analyse the power consumption for UWB in mobile devices based on competing short-range wireless technologies such as Bluetooth and Wi-Fi as references. Finally we present the key issue that will be considered in the design of an optimal MAC layer that will fully exploit UWB potential as a low-power, high data rate, short range wireless transmission system

Portable fingerprint-based attendance recording and monitoring system

This paper presented the development of a portable attendance monitoring system based on fingerprint identification that can be used by lecturers to monitor attendance of students. Fingerprint-based identification is one of the oldest method among all biometric or security techniques which has been successfully used in numerous applications. Every person has unique, immutable fingerprints. A fingerprint is made of a series of ridges and furrows on the surface of the finger. The distinctiveness of a fingerprint can be determined by the pattern of ridges and furrows as well as the minutiae points. Minutiae points are local ridge characteristics that occur at either a ridge bifurcation or a ridge ending. A portable fingerprint scanner has been utilized as the input to acquire fingerprint images and a laptop equipped with attendance recording and monitoring software as a mobile terminal to process the fingerprint images and record the attendance. This system can be used by lecturers to replace the old method of attendance recording, so that the integrity of the attendance record can be upheld. The actual student’s attendance can be recorded and stored in database. The system is also capable of processing the record to determine students who do not fulfill the attendance percentage requirement

UWB MAC Design Constraints and Considerations

In this paper, we consider the possibility of developing an optimal medium access control (MAC)layer for high data rate ultra-wideband (UWB) transmission systems that transmit minimal power. MAC in UWB wireless networks is required to coordinate channel access among competing devices. The unique UWB characteristics offer great challenges and opportunities in effective UWB MAC design. We first study the background of UWB and available MAC protocols that have been used in UWB. Secondly, we explore the constraints on UWB MAC design. Finally we present the considerations that need to be made in designing an optimal UWB MAC protocol

A Low Profile Switchable Pattern Directivity Antenna using Circular Sectorized EBG

In this paper, a low profile patch antenna switchable radiation pattern diversity with total thickness o

A Novel Technique of Controlling Signal Propagation within Array Elements using Switchable Miniaturized Electromagnetic Band Gap

In this paper, a novel miniaturized capacitive loaded electromagnetic band gap (EBG) has been developed with the patch size of approximately !/36. The dimension is controllable using the lumped capacitive elements values. The surface impedance characteristic of the EBG structure is switchable as pin vias have been inserted and removed within the EBG center and the ground plane. Switching the EBG surface impedance characteristic within the array elements has demonstrated the novel application of miniaturized EBG to control the signal propagation within the array elements. Radiation pattern for the middle antenna is enhanced toward the antenna which connected with low surface impedance EBG structure resulting approximately 12dB improvement in gain. The propagation characteristics and gain of the array have been analyzed using CST Microwave Studio (CST MWS). The new application of the EBG can be very useful to realize the controlling and channeling the signal within the array elements

Development of low-cost IoT-based wireless healthcare monitoring system

According to studies, up to 99 percent of alarms triggered in hospital units are false or clinically insignificant while indicating no genuine harm to patients. However, false alarms can lead to alert overload, causing healthcare workers to miss critical occurrences that could be harmful or even fatal. The purpose of this work is to tackle the problem by developing an integrated system that can continually track the patient's health condition utilising a cloud computing platform, allowing alerts to be targeted to the appropriate medical facility personnel in a timely and orderly manner. Arduino microcontrollers are used to collect health parameters such as temperature and pulse rate and provide a real-time monitoring system for medical practitioners. Multiple sensors and an RF transceiver are attached to a small microcontroller, forming a wearable module that the patient will wear. This wearable component is wirelessly connected to the main module consisting of a larger microcontroller, where the data is then uploaded to the database in the cloud through the internet. The data can then be accessed through a web-based terminal, providing medical practitioners access through the web page. If the system detects any abrupt changes to the patient's temperature or pulse rate, a push notification will be sent to the medical practitioner's Android smartphone so that immediate action can be taken. The system is scalable as multiple wearable modules can be connected to the main module, allowing monitoring of multiple patients simultaneously. More sensors can also easily be added to the wearable module to monitor other vital health parameters such as oxygen saturation and blood pressure. The testing has indicated that the system can achieve 99.4% accuracy in temperature monitoring and 86% accuracy for pulse monitoring

A Preliminary Study Of Characterization Techniques For Reticle ESD Threshold Voltage Measurement

Recent studies have revealed that reticle robustness towards electrostatic field is reducing since the feature’s critical dimension is getting smaller. Reticle electrostatic damage is seen after the features was subjected at low Electrostatic Discharged (ESD) voltages. This characterization was conducted on a Chrome-on-glass (COG)/Binary reticle metal layer for Complementary Metal Oxide Semiconductor (CMOS) 250nm technology node. International Technology Roadmap for Semiconductor (ITRS) and Semiconductor Equipment and Materials International (SEMI) uses the results of this reticle electrostatic damaged characterization, extrapolates it and establishes electrostatic field limits for semiconductor industry. Generally, a semiconductor wafer fabrication company will refer to this guideline to set up an Electrostatic Protective Area (EPA) for the expansion of current facilities or new facilities. As CMOS technology node shrinks further to 130nm, the photolithography process becomes more challenging since it requires printing smaller features accurately. A newly advanced reticle, called PSM (Phase-shift Mask) reticle has been introduced. PSM reticle features are made of Molybdenum Silicide (MoSi) material, which is different from the Binary reticle that uses Chromium. Existing guideline for electrostatic control limit from ITRS and SEMI may not be sufficient to protect PSM reticle from ESD damaged due to the different material features and the smaller critical dimension (gap distance between two parallel lines). This paper proposed a future work for characterizing PSM reticle ESD threshold voltage measurement and documented the result in ITRS and SEMI as separate guideline. This study will benefit semiconductor industry to implement more accurate EPA according to reticle type and technology node. The previous characterization techniques will be reviewed and critically compared in order to gain a better understanding of the reticle ESD damaged mechanism and propose new techniques for characterizing reticle that reflect actual production environment, the latest features material and lower technology node

Improved Location And Positioning Utilizing Single MIMO Base Station In IMT-Advanced System

This paper discusses an improvement of location and positioning estimation using one of the IMT-Advanced systems known as the mobile WiMAX. The Single MIMO Base Station (SMBS) in mobile WiMAX is combined with a virtual technique, known as the Virtual Base Stations, created a novel algorithm for location and positioning (L&P) purposes. This algorithm based on the angle of arrival (AOA) and angle of departure (AOD) measurement parameter completed the new SMBS algorithm with virtual base station (SMVirBS). The developed algorithm includes the effect of the geometric dilution of precision (GDOP) to assist with the location estimation accuracy. The simulation results showed that the proposed SMVirBS technique always outperforms the linear least square (LLS) algorithm in terms of estimated location accuracy. The technique also has the capability to work well in non-line of sight errors (NLOS)