A dual‐band dual‐mode microstrip Yagi antenna with quasi‐end‐fire radiation

Abstract

A dual‐band dual‐mode microstrip Yagi antenna with quasi‐end‐fire radiation patterns is proposed in this paper. It consists of five radiating patches driven by a single slot‐loaded patch placed in the middle. Meanwhile, two slot‐loaded parasitic patches are symmetrically located on two sides of the driven patch, respectively. In the lower band, the five patches involved resonate at TM01 mode. While in the upper band, all the patches resonate at TM02 mode. In order to ensure quasi‐end‐fire radiations in the both bands, four slots are symmetrically etched around the strongest surface currents of each patch resonating at TM02 mode. As a result, the resonant frequency of TM02 mode is decreased dramatically, while the resonant frequency of TM01 mode almost remains unchanged. With these arrangements, the separations between any two of the adjacent patches at their centers satisfy the requirements in design of the microstrip Yagi antenna in both bands, so as to realize the dual‐band dual‐mode microstrip Yagi antenna on a single‐layer substrate. Finally, an antenna prototype is fabricated and tested. The measured results reveal that the dual operating bands of 2.76~2.88 and 4.88~5.03 GHz for |S11| < −10 dB are satisfactorily achieved. Most importantly, the proposed antenna can indeed realize the quasi‐end‐fire radiation patterns in dual operating bands.

A high selectivity planar filtering quasi‐Yagi antenna

“…Thanks to the advantages of low profile, high direction and easy to integrate, planar quasi-Yagi antennas are widely used in communication system. 2,3 However, traditional planar quasi-Yagi antennas suffer from the drawback of narrow bandwidth. To broaden the bandwidth of the antenna, many techniques are proposed in References 4-7.…”

“…This kind of antenna mainly consists of three elements in the same substrate, which are the driven element, directors, and reflector. Thanks to the advantages of low profile, high direction and easy to integrate, planar quasi‐Yagi antennas are widely used in communication system 2,3 . However, traditional planar quasi‐Yagi antennas suffer from the drawback of narrow bandwidth.…”

Design of wideband end‐fire composite microstrip‐monopole antenna

“…The traditional end‐fire antenna type is Yagi antenna, which owns superior endfire performance with reflectors and directors. With the development of printed circuit board technology, planar printed Yagi antennas 1‐4 are also attracted many attentions due to several favorable features, such as compact size, lightweight, and low cost.…”