Circularly polarized slot antenna array with sequentially rotated feed network for broadband application

Abstract

This article presents a novel circularly polarized sequentially rotated slot antenna array (CPSSAA) designed to operate at a frequency of 5.5 GHz. This antenna is suitable for communication applications such as WLAN/WiMAX. Method of feeding is based on sequential rotation with seven quarter-wavelength transformers. In this case, the elements with 200 X impedance could be replaced by other elements with different input impedance. Reducing the elements input impedance, maximum power can be transferred to the elements. Because the lower losses in transmission line occur in presence of lower impedance, the 3 dB axial-ratio bandwidth of the CPSSAA extends to~1.3 GHz. The CPSSAA was designed to operate over the frequency range between 4.5 and 6.4 GHz corresponding to an impedance bandwidth of 34.86% for VSWR < 2. Acceptable agreement between the simulation and measured results validates the proposed design.

A Novel Wideband Circularly Polarized Patch Array With Meta-Surface

“…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].…”

“…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. Various antenna arrays are designed with sequentially rotated technique in [9][10][11][12][13][14][15]. In [9], a 2 × 2-element circularly polarized microstrip antenna array with the sequential-phase feeding network operating in Ka band was proposed.…”

Compact broadband circularly polarized slot-patch antenna array

“…Recent researches have focused on designing antenna array with a sequential‐phase (SP) feeding network. So far, various 2 × 2 microstrip antenna arrays with the SP feeding network have been reported, that is, patch antennas and slot antennas . However, these antennas have used narrow band radiating element and the axial ratio (AR) BWs of the resulting antenna arrays are limited by 34% .…”

Circularly Polarized 2×2 Mimo Antenna for Wlan Applications

“…Similarly, a focused antenna array with L-shaped slot helps in generating CP mode, when etched in an oppositely chopped inset feed patch [9]. A sequentially rotated slot antenna structure can generate CP polarized wave for maximum power transfer [10].…”