Circularly polarized 2‐arm spiral antenna for 60‐GHz applications

Abstract

A wideband circularly polarized (CP) 2-arm spiral antenna is designed for 60-GHz applications in this letter. The proposed antenna is implemented on a single layer with spiral printed on the top surface of the substrate and fed in a differential way through 2 metallized via holes. Unidirectional radiation is achieved thanks to the presence of the ground plane, which is placed with a distance of one-quarter of the guided wavelength to the spiral. A cavity is mounted on the top of the spiral antenna to suppress the surface wave propagate along the substrate as well as to improve the antenna gain. Experimental results show that the prototype achieves the 210-dB impedance bandwidth from 55.2 to 66 GHz with circular polarization. The peak gain at boresight is 9.5 dBi occurring at 63 GHz and the radiation patterns are stable over the operating frequency band.K E Y W O R D S circular polarization, differential feeding, millimeter-wave (mmWave), 2-arm spiral antennaAbstract A cryogenic measurement setup for characterization microwave devices from room to cryogenic temperatures is presented. The setup allows testing microwave devices at variable temperatures ranging from 300 to 77 K. Frequency doubler (94/188 GHz) has been cooled to 77 K and peak efficiency of 32% at an input-power level of 207 mW is achieved. For verification experimental results the RYBALKO | 3123

High‐gain wideband circularly polarised mm‐wave antenna with highly symmetrical radiation patterns

“…Figure 17 exhibits the measured radiation patterns of the proposed antenna at four different frequency points. This figure well confirms that the antenna has stable and symmetrical radiation patterns in different elevation planes over a wide frequency band (21)(22)(23)(24)(25)(26)(27)(28)(29). It is also noticed that the half-power beamwidth of the proposed antenna keeps nearly unchanged in different elevation planes.…”

“…Considering that the dielectric loss and radiation loss are no longer negligible at mm-wave frequencies, the substrate integrated waveguide (SIW) is thus extensively deployed in designing mm-wave antennas due to its low loss, easy integration, and high power handling capability characteristics [5,6]. To date, a variety of mm-wave wideband SIW CP antennas were proposed, including the horn antennas [7][8][9], dielectric resonator antennas (DRA) [10][11][12], slot antennas [13][14][15][16][17], magneto-electric dipole antennas [18,19], parasitic patches loaded antenna [20], patch antennas [21][22][23], L-probe antenna [24], and spiral antenna [5,25]. In ref.…”