MIMO Positioning for IMT-Advanced Systems Based on Geometry Approach in NLOS Environments

In wireless communications, one of the main problems that deteriorate the accuracy of location and positioning (L&P) estimation is non line of sight (NLOS) propagation. With the advances of multiple input multiple output (MIMO) technology as one of the features of International Mobile Telecommunications-Advanced (IMT-Advanced) systems, it has become feasible to adopt the technology into the mobile location scenario. By exploiting the multipath characteristics of the MIMO system, it is possible to estimate the position of mobile stations (MS) by considering the capability of MIMO to mitigate the effects of non line of sight (NLOS) conditions. In this paper we developed geometric approach by utilizing the advantages of MIMO system and employ the time of arrival (TOA) as range measurements for improving location estimation in various NLOS environments. The performance of the proposed method has been evaluated through computer simulation. The results of our simulation demonstrate the advantages of the proposed algorithm in comparison with the conventional LLS algorithm meeting the Federal Communications Commission (FCC) requirements

Utilising MIMO for Location and Positioning in IMT -Advanced Systems

With the advances of multiple input multiple output (MIMO) technology as one of IMT-Advanced features, it has hecome feasible to adopt the technology into the mobile location scenario. By exploiting the multipath characteristics of the MIMO system, it is possible to estimate the position of mobile stations (MS) by considering the capability of MIMO to mitigate the non line of sight (NLOS) conditions that deteriorate the accuracy of location estimation. In this paper we developed geometric approach by utilizing the advantages of MIMO system and employ the time of arrival (TOA) as range measurements for improving location estimation. The performance of the proposed method has been evaluated through computer simulation. The results of our simulation demonstrate that the proposed algorithm is significantly more effective in location accuracy than the conventional technique (LLS algorithm) and MIMO antenna configurations can achieve high accuracy for location estimation which meets the Federal Communications Commission (FCC) requirements

Eye Closure and Open Detection Using Adaptive Thresholding Histogram Enhancement (ATHE) Technique and Connected Components Utilisation

Eye closure detection is an important operation prior to carry out the main algorithm such as iris recognition algorithms, and eye tracking algorithms. This paper introduces a method to detect eye closure using Adaptive Thresholding Histogram Enhancement (ATHE) technique and connected component utilisation. The ATHE technique is a combination of histogram enhancement and estimation threshold technique. Firstly, in this proposed method the eye region is required to be localised. The ATHE technique enhances the eye region image then and yield the threshold value to segment the iris region. Based on the segmentation result, the connected components of binary image are used to classify the state of eye whether open or close. This classification is based on the shape and size of segmented region. The performance of the proposed technique is tested and validated by using UBIRIS, MMU and CASIA iris image database

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

Characterization of electrostatic discharge threshold voltage of phase-shift mask reticle

A reticle is a stencil used in lithography process for forming integrated circuit (IC) on silicon substrate. It consists of a thin (100 nm) coating of masking metallic patterned (features) with critical dimension (CD) of nanometers on a thicker quartz substrate. The features can be damaged by electrostatic discharge (ESD) when exposed to the environment electrostatic charge and caused deformed IC and eventually device difunctional. Semiconductor equipment materials industry (SEMI) standard established the allowable electrostatic charge on reticle based on the characterization of ESD threshold voltage on binary reticle. However, there is another type of reticle which is phase-shift mask (PSM), has not been characterized for its ESD threshold voltage. A direct current (DC) voltage is applied directly to the structures with CD of 80 nm, 110 nm, and 160 nm. The surface current is recorded at all levels of stress from 1 to 100 V. The current–voltage (IV) curve and physical inspection results for each cell are then reviewed and classified. The results yielded which no electric field induced migration (EFM) defect and breakdown voltage occurred at any of the structures. The cathode’s metal work function has been identified as the factor that influences the PSM reticle ESD threshold voltage

Experimental quantification of electrostatic damage (ESD) in binary reticle with feature of nanometre scale gaps

A Binary reticle for lithography circuit patterning is extremerly senstive to electrostatic field. Damaged is seen on its feature after a breakdown voltage occurred between the metal lines. The experimental quantification of ESD for Binary reticle is performed by direct discharge to the feature of Critical Dimension (CD) of 80 nm to 160 nm. Its breakdown voltage correlated to CD but lower than international standard recommendations and observed Electric Field-Induced Migration (EFM) damaged at CD of 110 nm to 160 nm

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