Mohamad Harris Misran

Design of Gaas E-phemt low noise amplifier for WLAN application

This paper describes the design of low noise amplifier using enhancement mode technology for WLAN front-end applications. Typical LNA designed for the IEEE802.1a standard is required to operate with low noise, high gain and exhibit low noise figure. The design uses feedback, and balanced topology to enhance the performance and to achieve the design goal. The LNA is designed operate at 2.4 GHz, noise figure (NF)<; 2dB, gain>;10 dB and with S11 and S22 <;-10 dB. With the voltage supply at 5 V, the total current consumptions for the LNA is 60 Ma.

An analysis of low pass filter using bowtie Defected Ground Structure (DGS) at 10 GHz for radar application

This paper describes the design of Low-pass filter using bowtie Defected Ground Structure (DGS). The designing of low-pass filter begins from lumped element in which the filter will be built using capacitors and inductors before converted to open and short circuited stub. The low-pass filter using bowtie Defected Ground Structure (DGS) is required to operate at 10 GHz for radar application. As a comparison, the design of different size and quantity of bowtie Defected Ground Structure (DGS) were analyzed to identify the better performance of the low-pass filter. The design of this filter had been simulated by using schematic and EM Simulation in Agilent Advanced Design System (ADS) software.

Design and performance analysis of single biasing based SPDT switch for wireless data communications

In this paper, a single biasing configuration for three different topologies of SPDT switch are designed in order to study the circuit performances based on insertion loss, return loss and isolation. In addition, current consumption of the three different topologies is discussed in this paper. The circuit topologies are series, shunt-shunt-shunt and series-shunt-shunt configuration. The targeted application is for wireless data communication such as WiFi, WiMAX and LTE. Design and analysis have been performed in a simulation software where a commercialize PIN diode model has been taken into account. As a result, single biasing based series-shunt-shunt topology gives the best option for SPDT switch design if looking at high isolation performance and good return loss with minimum current consumption.

Comparison on IV characteristics analysis between Silicon and InGaAs PIN photodiode

This paper presents comparison on IV Characteristics analysis between Silicon and InGaAs PIN Photodiode. PIN Photodiode is a structure that is consists of positive region, intrinsic region and negative region (PIN). The thick intrinsic regions are a difference to a normal PN Photodiode. PIN Photodiodes practical as Photodetectors, Attenuators and Radio frequency (RF) switches. The simple, low cost yet rugged structure of PIN Photodiodes is an advantage in Photodiode technology. These papers are separated in several section consists of the basic principle, characteristics, advantages and the recent technologies of PIN Photodiode. There will be a specific section on comparison between Indium Gallium Arsenide (InGaAs) PIN Photodiode with Silicon (Si) PIN Photodiode.

Wireless network visualization in 3D virtual environment framework

Simulating a signal propagation of wireless cognitive network has been widely accepted by researchers in order to come out with three-dimensional (3D) representation data display. Instead of using primitive way to understand the behavior of signal propagation, 3D visualization of wireless networking could also help researchers to study the limitation and exploration of wireless cognitive network deeply. In this paper, we would like to address the requirement and the potential of using 3D representation to visualize properly the wireless cognitive network. We also performed preliminary test of our 3D visualization system using OpenGL graphic library to visualize the propagation of signal travelling in specific room with several medium. The test has been conducted in order to understand the requirement of wireless cognitive network in 3D visualization before the actual system is built.

Investigation of triangular, circular and ellipse slots of Vivaldi antenna

This paper discussed on simulation investigation of triangle slot, circular slot and ellipse slot of Vivaldi antenna in term of bandwidth, reflection coefficient, gain and directivity which is operated at frequency of 10 GHz. Firstly, a normal Vivaldi antenna using FR-4 substrate had been designed and the single slot and double slot is developed. The double ellipse slots from 1mm to 5mm the gain and directivity increase from 5.460 dB to 6.805 dB and from 5.699 dBi to 7.136 dBi within their respective operating band. The advantages of a Vivaldi antenna such as simplicity, wide bandwidth, and high gain at microwave. This proposed antenna had been designed and simulated using Computer Simulation Technology (CST) simulation software.

Performance analysis of InGaAs/InP avalanche photodiode by using different guard ring structures

Avalanche Photodiode based on InGaAs/InP was chosen because of the needs of high speed optical receivers and have their own advantages on high sensitivity. In this project, we focused on the effect of guard ring on InGaAs/InP avalanche photodiodes and its performance. Three types of guard ring structures are designed in APD and their current-voltage (I-V) characteristics (electric field profiles) are simulated and analyzed. In this paper, the characteristics of guard ring in InGaAs/InP are investigated using Silvaco software, TCAD tools. This paper investigates the effects of guard-ring (GR) structures on the performance of InGaAs/InP avalanche photodiode (APDs) designed in Silvaco TCAD. Three type InGaAs/InP-APDs based on P+/N-well guard ring, n+/p-substrate guard ring and no presence guard ring are designed and their electric field profiles are simulated. In others to know the best structures of InGaAs/InP avalanche photodiode structures, the current-voltage characteristics (I-V characteristics) are mea...

Feed lines effects on UWB double sided circular disc bow-tie antenna

In this paper, presented a single double-sided circular disc bow-tie antenna for Ultra Wide Band (UWB) communication is being proposed. The antenna covers the UWB spectrum from 3.1 to 10.6 GHz, and had a return loss below than 10 dB throughout the entire band. The antenna feed lines were analyze in order to maximize the performance of UWB antenna. A compact antenna area of 30.0 × 60.0 mm2 is obtained. The material used is FR-4 epoxy glass substrate that has dielectric constant, εr = 4.4 and the dielectric thickness; h =1.6mm. The antenna also gives omni directional radiation characteristics with reasonable gain values over the same frequency band.

Variable junction temperature analysis in Silicon IMPATT diode

This paper proposed a design of SDR Silicon IMPATT diode in lateral structure and analyzes the variable junction temperature analysis in Silicon IMPATT diode. The simulation on the effect of junction temperature on electric field and carrier mobility is carried out for Si SDR IMPATT structure designed at D-band frequency. Result show that electric field increases while the carrier mobility decreases in higher junction temperature.

An investigation of drugs detection technique using RF radiation exposure in room temperature

In this technical paper contains the information of the Radio Frequency (RF) exposure along 10 MHz to 3 GHz frequency on pharmaceutical medicine where in this testing Paracetamol were tested. The samples were prepared at five different mol (10, 20, 30, 40 & 50 ml) and three different distances (5, 10, 15 cm) between horn antenna and the samples. The reactions from the medicine due to RF radiation are measured at S11 by fixed distance versus varied mol and fixed mol versus varied distance. The quasi-static technique and the RF exposure results, with respective specification was included and discussed.