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Dual-band slot microstrip patch antennas with dual-radiation modes for wireless communication
In this paper, a novel compact dual-band microstrip patch antenna with dual-radiation modes is investigated. The proposed antenna consists of a rectangular ground plane, a U-shaped feed probe, and an H-shaped slot radiating patch. By adjusting the size of these structures, a dual-band antenna can be obtained. In the low-frequency band, the antenna can radiate one radiation beam with high gain. In
A high selective tri-band bandpass filter with switchable passband states
A new class of switchable bandpass filter using PIN diodes is presented in this paper. The design aims at achieving a multistate switchable bandpass filtering characteristics between the passbands centered at 2.4, 3.5, and 5.2 GHz. The proposed filter is designed by assembling two /2 open-ended and four short-ended /4 uniform impedance resonators. The open-ended resonator generates a fixed passban
A novel reconfigurable microstrip fractal UWB antenna with six variable rejection frequency bands
In this paper, a new reconfigurable microstrip fractal ultra-wideband antenna with a capability of variable rejection frequency bands is presented. The main patch of this antenna has two modified -shaped gaps. Also, on these -shaped gaps, 10 ideal MEMS switches are used to produce band-notch frequencies at six different frequencies of: 5.4 GHz (5.2?5.5), 5.8 GHz (5.7?5.9), 6.1 GHz (5.9?6.3), 7 GHz
MRF volume 12 issue 1 Cover and Back matter
MRF volume 12 issue 1 Cover and Front matter
Realization of transmission zeros for bandpass filter using inductive-coupled stub-loaded resonators
This article proposes a bandpass filter with three controllable transmission zeros (TZs) using three inductive-coupled stub-loaded resonators (SLRs). Different from other works, the proposed SLR can create one transmission pole and one TZ. With the TZs above the passband, high stopband rejection level is achieved. Moreover, the -inverters are realized by short-circuit stubs between two adjacent SL
A novel compact lowpass filter with sharp roll-off and wide stopband
In this paper, a microstrip lowpass filter adopting two main resonators with steep transition band and wide rejection band has been introduced. The first main resonance cell consists of meandered transmission lines which are loaded by modified T-shaped patches. The second main resonator is composed of high-impedance lines loaded by polygon patches. To obtain a steep skirt performance, the first an
Measurement method for characterizing a millimeter-wave traveling-wave power combiner using test accessories
This paper presents a novel assessment method that minimizes test-fixture-induced errors in non-coaxial power combiner measurement by extending the port reduction method. This method involves terminating certain ports to acquire the scattering matrix of an -port network from the scattering matrix measured at a reduced port order. The entire DUT scattering matrix is obtained from multiple scanning
Experimental validation of an isoflux Earth coverage with a bimode ARMA antenna on a nanosatellite
Spatial telemetry links on nanosatellites require more and more reconfigurable beam antennas to improve the Earth coverage. The bi-mode Agile Radiating Matrix Antenna (8.0?8.4 GHz) was successfully designed to solve such kind of problems by using an isoflux mode associated with a switchable directive one. However, such an antenna introduces some manufacturing problems , mainly due to the small ava
Dual-function radar?communications: information transmission during FDA radar listening mode
We investigate the frequency diverse array (FDA) for joint radar and communication systems. The basic idea is to use the transmitter/receiver modules of the radar system for communication purpose during listening mode as a secondary function. The radar will be performing its routine functions during the active mode as a primary function. An FDA at the transmitter side will be used to produce an or