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A compact single layer branch-line coupler for ultra-wideband (UWB) applications
This paper presents the design of a compact, planar, single layer, tri-section ultra-wideband (UWB) branch-line (BL) coupler. The prototype offers 10 dB return loss characteristics from 3.1 to 13.7 GHz. Over a major portion of the band, phase imbalance of ±10° is achieved. The method of deploying multi stage impedance feed has been used to achieve improved bandwidth. To enhance the power output th
Design of a compact wide band microstrip antenna with very low VSWR for WiMAX applications
A single-layer coaxial-fed compact rectangular microstrip antenna with very low voltage standing wave ratio (VSWR) is presented in this paper. The simulated VSWR of the proposed antenna 1.00374 is obtained near the center frequency of the operating band (3.5 GHz). Simulation and measurement results indicate that the bandwidth (simulated: 3.36?3.715 GHz, and measured: 3.295?3.645 GHz) of the antenn
Aperture-coupled ESPAR antenna with unique feed network for symmetric switched beam radiation patterns
Aperture-coupled ESPAR antenna with a unique feed structure for switched beam application has been presented. The feed structure provides control over surface current of the driven element with the help of which main lobe can be steered in desired direction. This control has been achieved through the use of PIN-diodes. Finite element method has been utilized for design and simulated and measured r
A compact CPW-fed wideband metamaterial-inspired antenna for GSM, WLAN/Wi-Fi, and WiMAX applications
A compact coplanar waveguide (CPW)-fed wideband metamaterial-inspired antenna is designed and developed in this paper. The proposed structure is an asymmetric structure in which three rectangular stubs are employed between signal patch and CPW ground plane. It is demonstrated that these stubs provides lumped parameters of conventional epsilon-negative transmission line (ENG-TL). As an advantage of
Small-size LTE/WWAN monopole antenna with octa-band operation for 4 G mobile phone
By introducing a modified F-shaped feeding strip and dual parasitic shorted strips, a small-size wireless wide area network/long-term evolution (WWAN/LTE) printed antenna is proposed and embedded in the 4 G mobile phone with octa-band operation. The operating impedance bandwidths (RL ? 6 dB) of 263/1093 MHz can be obtained across the LTE/WWAN bands, respectively. The overall antenna size of the pr
Microwave photonic network for active electronically scanned array radar
Active electronically scanned array (AESA) radar has large number of T/R) modules which require multiple microwave and digital signals. Distribution of these signals through conventional method such as coaxial cable, twisted pair, etc. not only introduces engineering complexities and signal loss but also have limitation of bandwidth, data rate, transmission distance, etc. This paper addresses desi
Dielectric characterization using FEM modeling and ANNs for coaxial waveguide with conical open ended radiation
Since last decades, microwaves have received tremendous attention as an interesting tool for material characterization. In general, standard microwave measurement methods require cutting and polishing of samples to put it in a suitable waveguide or cavity. However, several methods have been developed in order to permit a non-destructive measurement. A well-known method is based on coaxial open-end
Development of compact inductive coupled meander line RFID tag for near-field applications
The development of compact radio frequency identification (RFID) tag is the key requirement for wireless tracking of precious small size goods/packages in transport. A design of compact meander line tag antenna having inductive coupling feed is presented for RFID system operating at ultra high frequency band of . The size of the proposed tag antenna is , and is designed using Higgs 4 IC chip (made
A switchable bandstop-to-bandpass reconfigurable filter for cognitive radio applications
This paper presents a simple reconfigurable bandpass filter switching from to based on PIN diodes. The proposed filter is intended to add frequency-tunability to antenna systems used in cognitive radio applications. It consists of a bent connecting stub with two open-circuited quarter-wave stubs grounded via PIN diodes. By controlling the didoes states, the electrical length of the stubs can be
Analysis and design of a triple band metamaterial simplified CRLH cells loaded monopole antenna
The design and analysis of meta-material inspired loaded monopole antenna for multiband operation are reported. The proposed antenna consists of multi resonators inspired from half mode composite right/left handed cells, which has a simple structure, compact size, and provides multiband functionalities. As a proof of concept, a triple band antenna covering all possible WiMAX operating bands, has b