A novel design of a microstrip‐fed shorted square‐ring slot antenna for circular polarization

Abstract

The design of a circularly polarized slot antenna fed by a single microstrip line is presented. The circularly polarized radiation is achieved by means of using a shorted square‐ring slot. This proposed antenna has the fundamental resonant frequency of 2.4 GHz with the minimum return loss of −50.44 dB. The impedance bandwidth is 930 MHz or 38.7% referred to the resonant frequency, and it also has the 3‐dB axial‐ratio (AR) bandwidth of 310 MHz or 12.9% referred to the resonant frequency. In addition, this proposed antenna shows good performance of circular polarization (CP) radiation with the range of the lower 3‐dB AR value covering elevation angles between −40 to 40 degrees. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1684–1687 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22517

A New Triple Band Circularly Polarized Square Slot Antenna Design With Crooked T and F-Shape Strips for Wireless Applications

“…The optimized value of the L 16 is given in Section 2. It can be observed that increasing the length of L 16 , causes a decrease on the center frequencies of all three impedance bands. But the change of the first band is more noticeable.…”

“…The impedance matching bandwidths of the first and third bands become much smaller when the length of L 16 increases, while the second band becomes much wider. On the other hand increasing the length of L 16 , creates the CP at the first band, between 2.38 ∼ 2.78 GHz, but through Figure 6, it could be understood that the CP bandwidth does not guarantee the impedance matching bandwidth for the same frequency band.…”

“…Embedding two spiral slots is also presented in [15], in which current circulation in the spiral slots are employed to achieve the CP operation. Utilizing a shorted square-ring slot is another way of creating CP antennas which is presented in [16]. Recently some annular-ring slots [18,20] are employed to achieve the CP characteristic.…”

Compact Design of Circularly Polarized Antenna with Vertical Slotted Ground for RFID Reader Application

“…References [5][6][7] realized the UHF RFID antenna but its size is too large to facilitate the practical application. References [8,9] developed a small circularly polarized RFID antenna, but the antenna bandwidth is so narrow that it cannot meet the requirements of UHF RFID applications. In this letter, a new compact CP and low cost design of a square-ring microstrip antenna with a vertical slotted ground plane are proposed.…”

A Perturbed Circular Monopole Antenna With Circular Polarization for Ultra Wideband Applications

“…In [5], an intricate UWB antenna with a CP band of 7.18-10.01 GHz was introduced. Presence of a ring type slot in antenna structure generates circularly polarized waves [6], whereas, shorted square-ring slot can create CP [7]. A circularly polarized square slot antenna loaded with a cross patch is published in [8].…”