Design and performance of a microstrip reflectarray on a uniaxial substrate

2002 ◽  
Vol 80 (1) ◽  
pp. 7-17 ◽  
Author(s):  
A Iliadis ◽  
K Siakavara
Keyword(s):  
Electromagnetic Field ◽  
Green's Function ◽  
Method Of Moments ◽  
Dielectric Substrate ◽  
Side Lobe ◽  
Side Lobe Level ◽  
Dual Polarization ◽  
Full Wave ◽  
Wave Technique ◽  
And Performance

A design formulation of microstrip reflectarrays is presented in this paper. Previous published articles, referring to this subject, present results for reflectarrays on a uniform dielectric substrate. In this work microstrip reflectarrays with offset feed, dual polarization, and side-lobe level under control, fabricated on a uniaxial substrate were studied. The method of moments, combined with the full-wave technique, and the corresponding dyadic Green's function is used for the specification of the electromagnetic field scattered by the array. PACS No.: 84.40B

scholarly journals Conventional vs. Convolutional Windows for Reduction of Side Lobes

2019 ◽  
Vol 8 (6) ◽  
pp. 1651-1654
Keyword(s):  
Side Lobe ◽  
Performance Comparison ◽  
Side Lobe Level ◽  
Two Stage ◽  
Linear Frequency ◽  
New Class ◽  
Window Functions ◽  
And Performance ◽  
Frequency Functions

Convolutional windows analysis and performance comparison with traditional windows is main intent of the present paper. Convolutional windows are formed by convoluting the window by itself. These new class of windows are applied to a pseudo-LFM signal designed by using two stage piece wise linear frequency functions. Simulations were performed for the designed LFM signal with both the traditional and convolutional window functions are is observed that the convolutional windows yield better peak to side lobe level ratio (PSLR) values compared to traditional windows.

scholarly journals Wideband Frequency Invariant Array Synthesis Based on Matrix Singular Value Decomposition

Electronics ◽  
2021 ◽  
Vol 10 (16) ◽  
pp. 2039
Author(s):  
Le Xu ◽  
Rui Li ◽  
Xiaoqun Chen ◽  
Feng Wei ◽  
Xiaowei Shi
Keyword(s):  
Singular Value Decomposition ◽  
Linear Array ◽  
Beam Width ◽  
Side Lobe ◽  
Singular Value ◽  
Side Lobe Level ◽  
Broadband Antenna ◽  
Full Wave ◽  
Half Power ◽  
Value Decomposition

In this paper, an analytic method for frequency invariant (FI) array synthesis is proposed based on matrix singular value decomposition. By grouping the elements of FI array into a few subarrays, the FI pattern in the whole frequency band is realized. Using this algorithm, the number of sub arrays is reduced. Simulation results show that the proposed algorithm can synthesize the 64-element broadband FI array in 0.52 s. For the 18-element linear array, the half power beam width (HPBW) changes less than 0.6 degrees in the bandwidth. Moreover, the range of HPBW variation decreases rapidly along with the increase in the number of elements. Furthermore, the effectiveness of the algorithm is verified by synthesizing FI array with low side lobe level (SLL), beam scanning, and notch requirements. The examples in this paper show that the proposed algorithm can achieve better pattern characteristics with fewer elements. Finally, a broadband antenna with 2:1 bandwidth is improved, and two FI arrays of 23 elements and 64 elements are formed by using the antenna. The active pattern of the array element is introduced into the proposed algorithm, and two FI arrays synthesized by the algorithm are simulated by full wave software.

scholarly journals Antena Susun Berpolarisasi Sirkular dengan Menggunakan Distribusi Daya Dolph Tschebycheff (Circularly Polarized Array Antenna Using Dolph Tschebycheff Power Distribution)

2020 ◽  
Vol 9 (1) ◽  
pp. 55-62
Author(s):  
Citra Zaskia Pratiwi ◽  
Achmad Munir
Keyword(s):  
Circular Polarization ◽  
Power Distribution ◽  
Axial Ratio ◽  
Dielectric Substrate ◽  
Side Lobe ◽  
Array Antenna ◽  
Side Lobe Level ◽  
Circularly Polarized ◽  
Measurement Results ◽  
Proximity Coupling

This paper discusses the design and realization of circularly polarized array antenna using Dolph Tschebycheff power distribution. The advantages of implementing circular polarization yield the array antenna suitable for outdoor communication system and can minimize the Faraday effect. The Dolph Tschebycheff power distribution is used to suppress the side lobe of array antenna. The proposed array antenna, which is intended to operate at the frequency of 5.3 GHz, consists of five square patch elements with seven diagonal slots upon each element to enhance the bandwidth and to produce the circular polarization. The array antenna is designed and realized using two layers of FR-4 epoxy dielectric substrate with the dimension of 119 mm × 44.1 mm and the thickness of 0.8 mm for each dielectric substrate. Each patch element is fed using a proximity coupling technique excited through a 50 Ω SMA connector. The measurement results show the bandwidth of 720 MHz, the side lobe level of 12.39 dB, the gain of more than 6 dBi around the frequency of 5.3 GHz, and the 3 dB axial ratio bandwidth of 200 MHz. It seems that the realized array antenna could produce wide bandwidth, low side lobe level, and circular polarization, so that it is suitable for WLAN application.

scholarly journals A Design Approach of Optical Phased Array with Low Side Lobe Level and Wide Angle Steering Range

Photonics ◽  
2021 ◽  
Vol 8 (3) ◽  
pp. 63
Author(s):  
Xinyu He ◽  
Tao Dong ◽  
Jingwen He ◽  
Yue Xu
Keyword(s):  
Phased Array ◽  
Phase Distribution ◽  
Beam Steering ◽  
Side Lobe ◽  
Design Approach ◽  
Optical Antennas ◽  
Side Lobe Level ◽  
Wide Angle ◽  
Spacing Distribution ◽  
Optical Phased Array

In this paper, a new design approach of optical phased array (OPA) with low side lobe level (SLL) and wide angle steering range is proposed. This approach consists of two steps. Firstly, a nonuniform antenna array is designed by optimizing the antenna spacing distribution with particle swarm optimization (PSO). Secondly, on the basis of the optimized antenna spacing distribution, PSO is further used to optimize the phase distribution of the optical antennas when the beam steers for realizing lower SLL. Based on the approach we mentioned, we design a nonuniform OPA which has 1024 optical antennas to achieve the steering range of ±60°. When the beam steering angle is 0°, 20°, 30°, 45° and 60°, the SLL obtained by optimizing phase distribution is −21.35, −18.79, −17.91, −18.46 and −18.51 dB, respectively. This kind of OPA with low SLL and wide angle steering range has broad application prospects in laser communication and lidar system.

scholarly journals Ka-Band Lightweight High-Efficiency Wideband 3D Printed Reflector Antenna

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Yu Zhai ◽  
Ding Xu ◽  
Yan Zhang
Keyword(s):  
High Efficiency ◽  
Near Field ◽  
Side Lobe ◽  
High Gain ◽  
Reflector Antenna ◽  
Field Analysis ◽  
Side Lobe Level ◽  
Ka Band ◽  
3D Printed ◽  
Reflecting Surface

This paper presents a lightweight, cost-efficient, wideband, and high-gain 3D printed parabolic reflector antenna in the Ka-band. A 10 λ reflector is printed with polylactic acid- (PLA-) based material that is a biodegradable type of plastic, preferred in 3D printing. The reflecting surface is made up of multiple stacked layers of copper tape, thick enough to function as a reflecting surface (which is found 4 mm). A conical horn is used for the incident field. A center-fed method has been used to converge the energy in the broadside direction. The proposed antenna results measured a gain of 27.8 dBi, a side lobe level (SLL) of −22 dB, and a maximum of 61.2% aperture efficiency (at 30 GHz). A near-field analysis in terms of amplitude and phase has also been presented which authenticates the accurate spherical to planar wavefront transformation in the scattered field.

Circular aerial arrays for radio astronomy

1961 ◽  
Vol 262 (1308) ◽  
pp. 84-99 ◽  
Keyword(s):  
Radio Astronomy ◽  
Side Lobe ◽  
Correction Function ◽  
Side Lobe Level ◽  
Circular Aperture ◽  
Circular Array ◽  
Polar Diagram ◽  
Beam Shape ◽  
Correction Process ◽  
Dimensional Distribution

A new type of aerial array suitable for high-resolution observations in radio astronomy is explored theoretically. The array consists of a large number of aerial elements equally Spaced round a circle and electrically connected in phase. The power polar diagram is calculated for the cases when the circle is effectively continuous, and when the separation between adjacent elements is appreciable. In both cases the side-lobe level is rather high for most radio astronomical purposes, for which a process of aerial correction is required. The function of the correction process is to readjust the relative weights of the different spatial Fourier components to provide a suitable beam shape. A general method of aerial correction is developed in which the two dimensional distribution of brightness directly recorded by scanning is cross-correlated with a circularly symmetrical correction function , a process which is desirably performed in the instrument itself. The correction process allows one to convert the polar diagram of a ring-shaped array into (for example) the diagram of a uniform circular aperture of the same radius. The principal theoretical characteristics of the circular array are briefly compared with those of the Mills cross. It is found that while the process of aerial correction or ‘tapering’ is technically more straightforward in the cross, the circular array has the following advantages: (1) the length of transmission line (and hence attenuation) between each element and receiver is halved; (2) the number of elements required to gain the same information is reduced, approximately in the ratio 4: π ; (3) the beam possesses circular or elliptical symmetry; and (4) the system offers the possibility of direct phase and amplitude calibration with the aid of a transmitter situated on a central tower.

Sign in / Sign up

Export Citation Format

Share Document