نتایج جستجو برای: Antenna Arrays

تعداد نتایج: 94493  

Journal: :رادار 0
محمد ساده لاری حبیب اله عبیری

in this paper, a resonant slotted waveguide array antenna with circular boundary has been designed and simulated for mono-pulse airborne radar applications. the antenna parameters are:11% bandwidth in x-band (8.6-9.6ghz),vswr < 2, 38dbi directivity, sidelobes level of - 20db and 3-db beam-widths of 2.1degree. to design this antenna, it is divided into short sections (sub-arrays) each with a uni...

In this paper two linear arrays including a linear 1×4 and a planar 2×2 of microstrip patch and half-mode substrate integrated waveguide (SIW) cavity hybrid antenna are introduced and investigated. These are simply implemented using low cost single layer printed circuit board (PCB) process. The array element consists of a rectangular microstrip patch with appropriate dimensions in the vicinity ...

Linear and planar antenna arrays are synthesized to have maximum directivity for a specified sidelobe level. The directivity is maximized subject to a given SLL. The beamwidth and the zeros of array factor are studied as well as the directivity. Maximum directivity-arrays are compared through some examples with super-directive, uniform, Dolph-Chebyshev and Riblet-Chebychev arrays to find a comp...

زراعتکارمقدم, جواد, فرخی, حمید, ندا, ناصر,

In this paper, the spatial MIMO channel modeling (SCM) is introduced and the required parameters for this modeling are studied. Then, the MIMO channel gains and capacity are analyzed. The transmitter and receiver antenna patterns are also analyzed. Next, we are focused on the effects of the transmitter and receiver antenna arrays separations, the arrays length, and the angles spread on the ante...

In this paper novel reflectarray antenna elements are proposed using aperture-coupled dielectric resonator antenna structures. Using these new structures, wide phase range and wide frequency bandwidth (up to 28.5%) with parallel and linear phase curves are obtained. In each case, an array consisting of 289 elements was simulated using the finite integration technique (FIT). The arrays exhibit 3...

2014
Priyanka Das Jibendu Sekhar Roy

Design of thinned semi-elliptical and quarter-elliptical antenna arrays, with uniform excitation and uniform spacing using genetic algorithm (GA) optimization, is presented in this paper. Thinned arrays produce narrow directive beam without causing major degradation of fully populated antenna arrays. Semi-elliptical array contains antenna elements along half of the elliptical geometry and quart...

2013
Subhash Mishra

Fault diagnosis in antenna arrays implies locating the faulty or defective elements in the array. Smart antenna arrays use digital beamforming and allow for array failure corrections. The defective elements of such antenna arrays therefore need not be replaced unlike the traditional analog approach. The smart antennas can thus support cost-effective solutions instead of replacing the hardware. ...

2007
Hon Tat Hui

Mutual coupling is a common problem in the applications of antenna arrays. It significantly affects the operation of almost all types of antenna arrays. Over the past years, there have been many different kinds of methods suggested to decouple (or to compensate for) the mutual coupling effect in antenna arrays. The effectiveness of these methods varied and depended upon the types of antenna arr...

2013
Rajesh Bera Jibendu Sekhar Roy

Design of thinned elliptical antenna arrays of uniformly excited isotropic antennas using particle swarm optimization (PSO), is reported. Thinned arrays can generate directive beam with minimum side lobe level (SLL) without degrading the performance of fully populated antenna arrays significantly. Thinning of elliptical antenna arrays using PSO are optimized with different values of eccentricit...

Journal: :رادار 0
محمدرضا مهدویانی نادر کمجانی

lenses are often used to converge electromagnetic wave namely they convert incident phase front of feed antenna to a flat phase front. together, the lens and the feed create an electrically large aperture antenna. flat lenses provide the cost and weight benefits of the reflect-arrays, while maintaining the advantages of a lens antenna. these lenses use an array of unit-cells which are excited b...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید