Reconfigurable Transmitarray with Near Field Coupling to Gap Waveguide Array Antenna for Efficient 2D Beam Steering
Journal article, 2020

A novel array antenna architecture is proposed that can enable 2D (full-space) radiation pattern control and efficient beam steering. This solution is based on a fixed-beam gap wave-guide (GWG) array antenna and a reconfigurable transmitarray (TA) that are coupled in the radiative near field. An equivalent two-port network model of the coupling mechanism is presented and validated numerically. The desired TA reconfiguration capability is realized by an 8×8 array of cavity-backed patch resonator elements, where two AlGaAs PIN-diodes are integrated inside each element providing a 1-bit phase shift. The TA is implemented in an 8-layer PCB, which includes radiating elements, fixed phase-shifting inner-stripline sections, impedance matching and biasing circuitry. The combined antenna design is low-profile (~ 1.7 wavelength) owing to the small separation between two arrays (~ 0.5 wavelength), as opposed to conventional TAs illuminated by a focal source. The design procedure of the proposed architecture is outlined, and the measured and simulated results are shown to be in good agreement. These results demonstrate 23.5 — 25.2 GHz –10-dB impedance bandwidth and 23.3 — 25.3 GHz 3-dB gain bandwidth, a beam-steering range of ±30° and ±40° in the E- and the H-plane with the gain peak of 17.5 dBi, scan loss ≤ 3.5 dB and TA unit cell insertion loss ≤ 1.8 dB.

gap waveguide


discrete lens

array lens

Phased antenna array

1-bit phase-shifting


Artem Vilenskiy

Chalmers, Electrical Engineering, Communication and Antenna Systems, Antennas

Mikhail Makurin

Samsung Research Institute Russia

Chongmin Lee


Marianna Ivashina

Chalmers, Electrical Engineering, Communication and Antenna Systems, Antennas

IEEE Transactions on Antennas and Propagation

0018-926X (ISSN)

Areas of Advance

Information and Communication Technology

Driving Forces

Sustainable development

Innovation and entrepreneurship

Subject Categories


Signal Processing

Condensed Matter Physics



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