A Compact Dual-Band Dual-Polarized Loop-Slot Planar Antenna

Abstract

This letter presents a compact dual-band dual-polarized loop-slot planar antenna. The antenna consists of a rectangular loop, a coplanar waveguide (CPW), and a microstrip line. The dual-band characteristic is realized using two different type resonant modes of the loop-slot antenna, namely, a loop basic mode in the lower band and a slot basic mode in the higher band. A CPW is used to excite vertical polarization modes and a microstrip line is used to excite horizontal polarization modes to achieve dual-polarized performance. The overall dimension of the prototype is only 2 57 55 mm . The proposed antenna is built and tested. It has two common -10dB impedance bandwidths of 420MHz (2.34-2.76GHz) and 660MHz (3.22-3.88GHz) to cover 2.4GHz WLAN band and 2.5/3.5 GHz WiMAX bands, respectively, and the isolation between the two ports is better than 21dB in the dual-band. The antenna has stable radiation patterns and gains in both bands. The antenna also has the merits of compact dimension, low cross-polarization, and low cost.

Mode investigation of parasitic annular ring loaded dual band coplanar waveguide antenna with polarization diversity characteristics

“…The 10 dB impedance bandwidth of antenna extends from 3.91‐5.31 GHz to 7.51‐8.72 GHz. The small difference between the measured and simulated results stems from the unavoidable errors in measurement process and the deviation of dielectric constant of actual from that used in the simulation . Circular polarized nature of lower band is confirmed by 3 dB axial ratio bandwidth which extends from 4.01 to 5.31 GHz, illustrated in Figure .…”

“…Multi band antenna with dual polarization characteristics reduces the requirement of multiple antennas along with reduction in multipath fading. Acknowledging the merits of dual band dual polarized (DBDP) antenna, various techniques and applications have been reported in the recent past . Shorting pins along with integrated capacitor have been used in Reference to realize first time dual polarization in microstrip antenna.…”

“…This design makes the antenna feasible with active components but antenna size and isolation between feed ports remains a big constraint of this design. Subsequently has been proposed but again involving multiple feed ports. Single port microstrip antenna with dual polarization characteristics is realized using offset feeding and annular slot, parasitic patch, stacked patch, artificial magnetic conductor, and slot coupled power divider .…”

A Wideband Dual-Polarized Modified Bowtie Antenna for 2g/3g/Lte Base-Station Applications

“…A number of broadband dual-polarized antennas have been developed for base stations. The conventional choices mainly include patch antenna [1][2][3], slot antenna [4][5][6] and cross-dipole antenna [7][8][9][10]. Patch antenna is popular with low profile, potential low cost, conformal nature, and ease of mass construction, but the use of patch antenna is limited because of its narrow bandwidth.…”

“…Although the antenna in [4] has a bandwidth of 45.8% (RL > 10 dB), it has a relatively low antenna gain and poor cross-polarization performance. The bandwidths of the slot antennas in [5] and [6] are far less than 45% (1.71-2.70 GHz) and they are only used for WLAN applications. The cross-dipole antenna is a good choice to achieve both dual polarization and broad impedance bandwidth.…”