Abstract
In this article, an elegant approach is presented for designing multi-band multi-mode rectangular microstrip antennas (MSAs) with high isolation between the bands. The coupling properties of a gap (an extended slot), which is introduced in a rectangular MSA operating in the $TM_{010}$ and $TM_{100}$ modes, are first qualitatively explained through field equivalence theory and image theory. It is shown that even though the slot appears “transparent” (i.e., strongly couples the two sections of the MSA) to the $TM_{010}$ mode, it effectively decouples the two sections of the MSA in the $TM_{100}$ mode. As a proof-of-concept, the design technique is applied to a conventional patch to achieve dual-band operation with $39~dB$ of measured isolation between the bands. The design concept is then extended to achieve a quad-band antenna design with $30~dB$ of measured isolation between all of its bands. Compared to other methods the proposed one preserves the low-profile of microstrip antennas and provides a simple way to design and fabricate multi-band and multi-mode antennas. Therefore, this method is very well suited for designing antennas for next generation communication systems.
Highlights
M ICROSTRIP antennas (MSAs), introduced in 1953, [1], and developed in the 1970s, [2]–[4], exhibit many advantages including low profile, small volume, and easy as well as low cost PCB fabrication
These results show that the jointly fed MSA (JFMSA) does not achieve any significant performance improvements over the conventional MSA (CMSA)
This study demonstrates that an increase in the dimension of the CMSA by as little as 0.07λo results in 9.9 dB and 5.4 dB higher isolation in the low- and high-bands, respectively
Summary
M ICROSTRIP antennas (MSAs), introduced in 1953, [1], and developed in the 1970s, [2]–[4], exhibit many advantages including low profile, small volume, and easy as well as low cost PCB fabrication. Numerous designs have been introduced for various applications, [5]–[7] Amongst these designs MSAs that provide dual-band, multi-band or wide-band operation have been extensively studied, especially with the rapid development of mobile communication systems, [8]–[11]. Multi-layer patches with multiple resonators have been proposed, [26], [27] All these designs, which provide high isolation between feeds, have increased complexity. A new design approach, which uses the coupling properties of slots, is proposed to support the development of simpler and lower cost multi-band designs. Extended slots are used, which cut conventional patches into pieces to achieve high isolation (in the order of 30 dB) between the feeding ports of multiband and multi-mode microstrip antennas. It can be applied to any microstrip antenna design
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
