X‐band antenna array for low‐cost beam scanning

Abstract

A concept of a low‐cost beamforming system is investigated by developing an inexpensive microstrip antenna array and proposing an appropriate approach for a beamforming. The antenna structure is composed of individually fabricated linear sub‐arrays suspended over the ground plane. The design is scalable, because an antenna array with required radiation pattern can be designed by using adequate number of linear sub‐arrays. A novel cone‐shaped transition surrounding the probe feed has been applied to decrease an inductive reactance of the input impedance. The antenna array composed of four linear sub‐arrays has been designed, fabricated and measured to validate performance of the proposed low‐cost design. The measured gain of a fabricated antenna is >26 dBi and the reflection coefficient is better than −10 dB. Each sub‐array has a separate coaxial connector, therefore beam scanning can be achieved by controlling radio frequency signals in each sub‐array. Two methods of beam scanning, a phased array approach and a time modulation approach, have been proposed and compared in terms of efficiency, cost and functionality.

Design and simulation of an analog beamforming phased array antenna

“…In analog beamforming technology, the phase of each signal received and transmitted by the antenna array element is adjusted, so that the radiation pattern of the antenna array is steered in the desired direction. The IF phase shifting is implemented in this research because it can provide much better performance compared to RF and LO phase shifting [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. The slotted waveguide antenna array is selected because it can provide high power handling capability, low loss, small size, narrow beamwidth, good bandwidth, and high gain [15][16][17][18][19][20][21][22][23][24][25].…”

Experimental investigation of beam-steering applied to 2 × 2 MIMO system with single receiving RF chain and time-modulated antenna array

“…It can be also obtained with a time-modulated antenna array (TMAA) which is considered as an unconventional beamforming architecture [4]. The TMAA concept was first proposed in 1959 [5] as an alternative to the PAA because fast radio frequency (RF) switching allows similar weighting of RF signals and switches have several advantages over phase shifters [6]. However, in contrast to the PAA, output signal of the TMAA is spread into multiples of the modulation frequency around the center frequency.…”