Reflective array antenna

About: Reflective array antenna is a research topic. Over the lifetime, 4366 publications have been published within this topic receiving 57884 citations.

Investigation of Using High Impedance Surfaces for Wide-Angle Scanning Arrays

Abstract: In this paper, an eight-element linear array is proposed and experimentally studied to illustrate the potential of using high impedance surfaces (HISs) for wide-angle scanning applications. An HIS-based horizontal wire antenna with a broad-beam radiation pattern is implemented as the individual radiating elements of the proposed array. The working mechanism of the HIS-based array is investigated as well. The rectangular-mushroom HIS, operating in surface-wave band, contributes to the broad-beam radiation of the individual antenna element as well as the wide scan performance of the array. Measured results show that with uniform magnitude and progressive phase excitation, the array performs a wide scan angle up to 85° in the elevation plane and a realized gain varying from 13.1 to 10.1 dBi. Meanwhile, the side lobe levels (SLLs) are generally less than $-10\;\mathbf{dB}$ over the entire scan region. Good agreement is obtained between the measurements and the simulations.

Active transmit phased array antenna.

Abstract: An active transmit phased array antenna system for generating multiple independent simultaneous antenna beams to illuminate desired regions while not illuminating other regions. The size shape of the regions is a function of the size and number of elements populating the array and the number of beams is a function of the number of beam forming networks feeding the array. All the elements of the array are operated at the same amplitude level and beam shapes and directions are determined by the phase settings. The active transmit phased array antenna includes a plurality of antenna elements disposed in a hexiform configuration. Each antenna element is identical and includes a radiating horn capable of radiating in each of two orthogonal polarizations. The horn is fed by a multi-pole bandpass filter means whose function is to pass energy in the desired band and reject energy at other frequencies. The filter means is coupled into an air dielectric cavity mounted on substrate. The air dielectric cavity contains highly efficient monolithic amplifiers which excite orthogonal microwave energy in a push-pull configuration by probes in combination with amplifiers placed such that they drive the cavity at relative positions 180 degrees apart. Phase shift means and attenuator means in the substrate are connected to the amplifiers in the cavity to determine beam and direction and for maintaining the signal amplitudes from each of the antenna elements at an equal level.

Study on Wide-Angle Scanning Linear Phased Array Antenna

Abstract: Two wide-angle scanning linear array antennas (E- and H-planes scanning linear array antenna) are studied and presented. In order to improve the wide-angle scanning performance of the phased array antenna, a wide beamwidth U-shaped microstrip antenna with the electric walls is designed. The wide-angle scanning linear array antennas are studied in the frequency band from 3.2 to 3.8 GHz. The 3 dB beamwidth of the antenna is 140° in the E-plane scanning linear array center and 220° in the H-plane scanning linear array center at 3.5 GHz. The main beams of the H-plane scanning linear array antenna can scan from −90° to +90° with a gain fluctuation less than 3 dB and a maximum sidelobe level (SLL) less than −5 dB. Simultaneously, the main beam of the E-plane scanning linear array antenna can scan from −75° to +75° with a gain fluctuation less than 3 dB and SLL less than −5 dB. The H- and E-planes scanning linear array antennas with nine elements are fabricated and tested. The measured results have a good agreement with the simulation results.

Dual-Polarized Sinuous Antennas on Extended Hemispherical Silicon Lenses

Abstract: This paper examines the performance of dual-linear sinuous antennas on silicon extended hemispherical silicon dielectric lenses. A theoretical impedance of 106 Ω is identified based on the analysis of an ideal self-complementary structure, and this result compares well with simulations and measurements. The radiation properties of a linearly polarized sinuous antenna are simulated using Method of Moments software coupled to a GO/PO code, and also agree well with measurements. The results indicate that the sinuous antenna is an excellent wideband planar feed for a silicon lens, with cross-polarization levels below -17 dB, and polarization variations of ±5° over two octaves in frequency. The application areas are millimeter-wave, wideband, dual-polarized radio-astronomy receivers.

Beamformer architectures for active phased-array radar antennas

Abstract: In active phased-array antennas, the transmit and receive functions are distributed at the antenna aperture using transmit and receive (T/R) modules. The use of T/R modules provides a significant improvement in antenna performance and flexibility in the choice of array architectures. We present a review of various beamformer architectures for active phased-array antennas. This review is limited to corporate-fed active phased-array antennas for radar applications. Beamformer architectures for narrow and wide bandwidth arrays, including the choice of applying an amplitude taper in the T/R module or beamformer network are discussed. Beamformer architectures that increase antenna reliability are also presented.