Md. Fokhrul Islam

E-Shaped Microstrip Patch Antenna for Ku Band

Technology has been developing day by day where satellite communication has become daily part of our life. As the technological devices are getting smaller demand for multiband operating antennas are growing faster to the consumers. This paper represents an E shaped Microstrip Patch Antenna for multiband operations in Ku band. The design has been made on low cost material of FR4 substrate having dielectric constant of 4.2 with thickness of 1.6mm. The proposed scheme and probe feeding technique provide designed antenna to operate in three different frequencies range in Ku band. The antenna resonates at 12.4 GHz, 13.28 GHz, and 14.45 GHz with directivity gain of 8.6, 9.5 and 7.4 respectively. Designing and simulation of this antenna has been done by IE3D software. In this paper different types of antenna characteristics have been studied.

Tunable bandpass filter using RF MEMS variable capacitors

The growing number of multi-standard and multi-application telecommunication systems has led to the development of new tunable filter topologies. Tunable filters are integral components in a variety of radar and modern multi-band communication systems [1]. The conventional tunable filters typically utilize YIG resonators, active resonators or varactors as the tuning element. However, these varactor based tuning filters have low Q values due to high series resistance of diodes. The development in microelectromechanical system (MEMS) technology allows new and innovative design of the tunable bandpass filters. In this paper, the concept in [4] is extended to design radio frequency (RF) MEMS tunable filters for wireless application.

Ku-band bandpass filter using surface micromachined process

This paper presents a Ku-band microstrip bandpass filter (BPF) based on surface micromachining technique. Surface micromachining technique is used for simplicity and ease of fabrication. Full-wave electromagnetic simulations are performed to accurately predict the frequency response of the filter. The filter is fabricated on 600 µm-thik silicon substrate which is compatiable with the new SiGe process. The fabricated filter occupies a chip area of 8 × 3 mm2 and achieved an insertion loss of less than 2 dB and return loss of less than −20 dB throughout the operation band. The filter has a center frequency of 15 GHz with a 3 dB bandwidth of about 6 GHz covering the frequency ranges from 12 GHz to 18 GHz. This filter is widely used today in radar, satellite and terrestrial communications applications.

Miniaturized Bandpass Filter for Ku-band Applications

This paper presents a low cost and low insertion loss Ku-band bandpass filter (BPF) based on inexpensive commercial FR4 (epsivr.= 4.3) substrate. The filter is designed on 0.6 mm-thik substrate using microstrip technology by following the design procedure based on even- and odd-mode impedances of the coupled lines. Microstrip technology is used for simplicity and ease of fabrication. The design and simulation are performed using 3D full wave electromagnetic simulator IE3D. The simulated filter occupies a chip area of 12 times 3 mm2 and achieved an insertion loss of less than 1.0 dB in the passband and maximum return loss of 12.0 dB throughout the operation frequency of Ku-band. The filter has a center fiequency of 16.0 GHz with a 3 dB bandwidth of about 5.8 GHz covering the frequency ranges from 13.2 GHz to 19.0 GHz. This filter is widely used today for the telecommunication satellite in the Ku-band transceivers.

Compact rectangular microstrip patch antenna for dual band application

A dual-band dual-polarized coaxially-fed single-layer microstrip patch antenna with a compact structure has been demonstrated. The proposed antenna with a bandwidth of 154MHz (f0=6.83GHz) and 209MHz (f0=9.73GHz) was designed and fabricated successfully. From the results obtained, it can be seen that this novel antenna is capable of satisfying some of the requirements of an airborne SAR, for example, the radiation pattern and bandwidth requirements. In additions, For high data collections and accurate knowledge of targets missions which could need several frequency bands, this concept allows to share between C and X bands SAR system. Beside this, the concept can be simply adapted to design other antenna operating at different frequency band.

Reliability Assessment of Micromachined Fixed–Fixed Beam Based on FE Simulation and Probabilistic Sampling

Recent trends in structural mechanics applications of finite-element methods (FEM) show an increasing demand for efficient analysis tools. This paper presents a realistic approach for modeling a fixed-fixed beam structure used in microelectromechanical systems based on finite-element analysis (FEA). The use of probabilistic methods to assess the electromechanical behavior of the beam under the presence of micromachine manufacturing and process uncertainties is also presented. The finite-element model of the beam is constructed using the commercial code ANSYS (10.0). In the standard approach of modeling, existing literature assumes deterministic values for design parameters. However, fabrication of the device introduces some amount of variation in these parameters. In this paper, the probabilistic approach is discussed to account for the variability in fabrication. FEA guides the design of fixed-fixed beam to achieve a robust and reliable design in a most efficient way. From the probabilistic analysis, it was observed that the changes in length and thickness tend to be the most influencing parameters, which need to be tightly controlled.

Design and Analysis of a Wideband Microstrip Antenna for High Speed WLAN

Allocation of frequency spectrum for Wireless LAN is different in different countries. This presents a myriad of exciting opportunities and challenges for design in the communications arena, including antenna design. The high speed WLAN has many standards and most antennas available do not cover all the standards. The primary goal of this work is to design antenna with smallest possible size and better polarization that covers all the high speed WLAN standards ranging from 4.90 GHz to 5.82 GHz. General Terms Antenna design, WLAN, Microstrip.

Design and Simulation of X-Band Micromachined Microstrip Antenna

There is an increasing demand for newer microwave and millimeter-wave systems to meet the emerging telecommunication challenges with respect to size, performance and cost. Micro electro mechanical systems (MEMS) have several desirable features, including small size, high performance, low power consumption and low loss. This paper presents an X- band probe fed small rectangular microstrip patch antenna based on high-resistivity silicon substrate which is capable to reduce the dimensions of the antenna. The antenna was designed on 0.375 mm-thik substrate using microstrip technology followed by probe feeding technique. Microstrip and probe feeding technique offer easy fabrication process using MEMS technology. The design and simulation of the antenna were performed using 3D full wave electromagnetic simulator IE3D. The antenna with a bandwidth of 118.14 MHz and a center frequency of 9.6 GHz which is within the allowable specturm (9.5-9.8 GHz) for Earth Exploration Satellite System (EESS) was simulated successfully.