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This paper describes the design and analysis of a Circular Polarization Fractal Koch Antenna using single-fed electromagnetic (EM) coupled ring resonator at 2.4 GHz. By applying fractal Koch, the proposed antenna size is reduced about 5% compared to the square patch using single-fed EM coupled ring resonator antenna. The simulation process has been done by CST software. Simulation as well as measurement...
In this paper, a method of shaping waveforms at drain for designing an inverse Class-F power amplifier is presented. The second and fourth harmonics are controlled by a simplified structure by employing the bias circuit. Then by tuning the phase of the second and fourth harmonic, and also third and fifth harmonic components in the load, the de-embedded voltage and current waveforms at drain are shaped...
Designing a filter with harmonic suppression capability without adding any external filtering capacitors or notch filter is a big challenge. The paper presents the design of a compact microstrip bandpass filter having integrated harmonic suppression capability. The filter operates at a center frequency of 900 MHz. The structure chosen is the Hairpin Filter. The conventional hairpin is modified by...
Dual operation antennas have gained importance in the development of compact structures. In this paper, a simple approach using graphical approximations is presented for the design of a dual-band antenna. An example of dual-band operation is for the GPS (Global Positioning System) satellite reception with frequencies in the L-band. The chosen antenna is the rectangular microstrip patch having two...
This paper presents preliminary investigation and design of a rectangular nano-antenna that exhibits pentahertz (PHz) radiation. A plasmonic material is proposed as the substrate to be used for the antenna. The configuration chosen for the antenna radiating element is the rectangular structure. Numerical simulation based on FDTD has been performed on the designed antenna with varying substrate thickness...
A 2.4GHz medium power amplifier (MPA) using 0.15μm GaAs PHEMT technology for wireless local area network (LAN) applications is demonstrated. At 3.0 V of drain voltage (VDS), a fabricated MPA exhibits the output power at 1dB gain compression (P1dB) of 15.20 dBm, power-added efficiency (PAE) of 12.70% and gain of 9.70 dB, respectively. The maximum current, Imax of this amplifier is 84.40mA...
This paper presents a preliminary study of the measurements of W-CDMA signal from mobile phone base station. The measurements are carried out inside an anechoic chamber. We employed a base station simulator and the frequency selective method using Narda Probe. We investigated the effect of the spectrum analyzer settings on the measurements of the electric field strength for different resolution bands...
Nowadays, superior data capacity can be achieved at a relatively low cost using Asymmetric Digital Subscriber Line (ADSL) technology through the existing copper cable network. The performance of ADSL technology strongly depends on line attenuation factor which is attenuation due to copper cable and connections. This paper presents the analysis of transmission loss at every connection stretching from...
This paper is to propose a multiband matched bandstop filter. A lossy resonator is proposed and it demonstrates the concept and design of a perfectly matched bandstop filter with a matched response.. The design is based on a half wavelength (λ/2) and quarter wavelength (λ/4) resonator with gap coupling, parallel with an all-pass nominally-90°-phase-shift element, which...
The design and deployment of efficient vehicle-to-vehicle (V2V) communications systems require the knowledge of the propagation channel in which it will operate. Due to the mobility of the transmitter/receiver terminals as well as the existence of dynamic scatterers, the V2V channel is nonstationary. To account for the nonstationarity, channel characterization methods that employs the non wide-sense...
This paper presents a thorough investigation of the effects of substrate thickness on the performance of infinite reflectarrays. The reflectarrays designed in the X-band frequency range are investigated in terms of electric field intensity, reflection loss and reflection phase performance. It has been demonstrated that the electric field intensity decreases from 3.42e5V/m to 2.34e5V/m as the thickness...
This article introduces a simple technique in two-dimensional multiport method for analysis of planar circuits. This technique is applicable to configurations which have been analyzed by desegmentation method with electric wall boundary condition at the removed parts. Analysis of planar circuits with metallic vias is performed faster and more accurate by this technique, because there is no need to...
This paper discuss the design considerations of a semianechoic chamber (SAC) for Science and Technology Research Institute for Defense's (STRIDE) to cater for electromagnetic compatibility (EMC) measurements in compliance to military and commercial standards. The SAC size is limited to the available space at STRIDE premise of 13.8 meters length, 5.88 meters width and 6.9 meters height. Similarly the...
The aim of this paper is to provide additional information about the performance of the SC EXCELL model, specifically when applied to the prediction of rain attenuation in equatorial and tropical regions. The model generates a long-term rain attenuation Cumulative Distribution Functions (CDF) that separately accounts for stratiform and convective precipitation. The model assessment in estimating attenuation...
We propose the methodology of field strength prediction for a digital television (DTV) receiver by virtue of Rec. ITU-R P.1546. The curves shown in this Rec. represent the point-to area field strength for 1kW effective radiated power in the 30 MHz ~ 3000 MHz. Some computed results are illustrated here from the formulation of field strength for DTV receiver. It was shown that the error of field strength...
In this paper, we presented a K-band Voltage Controlled Harmonic Oscillator (VCHO) with novel structure. The proposed VCHO is a structure of two hair-pin resonators placed on input and output of active device. By using in/out common frequency tuning structure, the VCHO produced some advantages of the enhanced characteristics of fundamental frequency suppression as well as the improved second harmonic...
This paper investigates the foliage effect on fixed wireless links based on IEEE 802.11a standard operating at frequency 5.8GHz of Unlicensed National Information Infrastructure (UNII) bands. Based on the studies of the measured received signal profiles under two different links, it is observed that the foliage obstruction gives significant effects on the link performance. The results from measurements...
The following topics are dealt with: antennas; radiowave propagation and microwave theory; electromagnetic compatibility; computational electromagnetics; RF devices; wireless communication technology; cellular communication technology; satellite communication technology; electromagnetic education; microwave integrated circuit; and cognitive radio.
A novel P-shape wideband dielectric resonator antenna design is presented for wireless application in this paper. It is described by using a P-shape dielectric resonator with high dielectric constant (εr = 30) that is placed on the truncated ground plane, a wideband impedance bandwidth of about 64% (for VSWR≤2), covering the frequency range of 3.40-6.58GHz is achieved. Analysis...
In this paper a novel design procedure to obtain wideband and small size dielectric antennas using high dielectric constant material is described. It is shown that by selecting the resonator shape and creating a notch on the dielectric resonator, it is possible to design rectangular dielectric resonator antenna which compact size and wide frequency coverage. Simple formulas are presented to illustrate...
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