A Wideband Sequential-Phase Fed Circularly Polarized Patch Array

Abstract

This communication presents a wideband circularly polarized (CP) 2 2 patch array using a sequential-phase feeding network. By combining three operating modes, both axial ratio (AR) and impedance bandwidths are enhanced and wider than those of previous published sequential-fed single-layer patch arrays. These three CP operating modes are tuned and matched by optimizing the truncated corners of patch elements and the sequential-phase feeding network. A prototype of the proposed patch array is built to validate the design experimentally. The measured -dB impedance bandwidth is 1.03 GHz (5.20-6.23 GHz), and the measured 3-dB AR bandwidth is 0.7 GHz (5.25-5.95 GHz), or 12.7% corresponding to the center frequency of 5.5 GHz. The measured peak gain is about 12 dBic and the gain variation is less than 3 dB within the AR bandwidth.

A Novel Wideband Circularly Polarized Patch Array With Meta-Surface

“…It shows an increased impedance and axial ratio bandwidths compared with [8] while a significant size reduction is proposed compared with the antenna proposed in [14]. Moreover, the gain is comparable to previous designs.…”

“…The proposed patch array has an overall size of 1.275λ o × 1.275λ o × 0.0935λ o at 5.1 GHz, which is considerably less than the previously published antenna arrays [11][12][13][14] and [8] as summarized in Table 1 (a) (b) along with other parameters. It shows an increased impedance and axial ratio bandwidths compared with [8] while a significant size reduction is proposed compared with the antenna proposed in [14].…”

“…Due to the advantages of wide band, light weight and ease of fabrication, the proposed antenna has wide and potential applications for wireless communications such as WLAN/WiMAX. Compared with the antenna in [8], which is similar to the proposed antenna, the proposed antenna has experimentally wider impedance and axial ratio bandwidths.…”

“…A 2 × 2-element planar array with sequential-phase feeding can generate circularly polarized characteristics. Various structures of the sequential-phase feeding networks have been proposed in [5][6][7][8]. These sequential-phase feeding networks with phases of 0 • , 90 • , 180 • , and 270 • at four ports have been extensively used to improve the impedance and axial ratio (AR) bandwidths in the 2 × 2-element array design.…”

“…Based on the antenna array in [8] and the corner-cut AMC structure in [20], a novel circularly polarized patch array with meta-surface is presented. The array consists of four rectangle patches, and each rectangle patch is truncated by two isosceles triangles in a diagonal direction.…”