In this study, a higher‐order mode suppression technique in single‐ and dual‐frequency microstrip antennas is proposed. The technique integrates a microstrip filter within the microstrip antenna, thereby simplifying the transmitter/receiver chain by eliminating the need of a separate filter. This technique gives higher‐order mode suppression of 8 dB using a low‐pass microstrip filter without any effect on the resonance frequency and the gain of the antenna. A dual‐frequency antenna for S and X bands is designed using this technique to obtain measured bandwidth of 7% and gain of 8 dBi at the S‐band and measured bandwidth of 10.5% and gain of 11.5 dBi at the X‐band. This antenna can be used for satellite applications.
Here, a dual‐frequency dual‐polarised shared aperture microstrip antenna (DFDP‐SA MSA) at S‐ and X‐bands with suppressed higher order mode is presented. The technique for higher order mode suppression comprises of a microstrip filter within the antenna, which eliminates the need of a separate RF filter in the transmitter/receiver chain. The antenna operates at two frequencies having high‐frequency ratio of 1:3.2 between them, which is utilised to its advantage by using cross‐shaped antenna at S‐band and 2 × 2 array of square patches at X‐band around it. This antenna gives measured bandwidth (|S11|≤−10thinmathspacedB) of 7.4% from 2.6 to 2.8 GHz (S‐band) with measured gain of 8 dBi at 2.5 GHz and measured isolation better than 18 dB between the orthogonal ports at S‐band. It gives bandwidth of 8.7% from 7.7 to 8.5 GHz (X‐band) with measured gain of 11.5 dBi at 8 GHz and measured isolation better than 28 dB between the orthogonal ports at X‐band. The antenna is extended to 2 × 2 array for higher gain.
In this paper, a novel configuration for linearly polarised Dual Frequency Microstrip Antenna at S-and X-bands is presented. The proposed configuration utilises the frequency ratio of 1 : 3.3 between the two bands to its advantage by saving space. It uses the antenna at S-band as ground plane for a 2 × 2 antenna array at X-band without any additional requirement of separate space and ground plane. The patches are electromagnetically coupled to give measured bandwidth (|S 11 | < −10 dB) of 13% at S-band and 6.2% at X-band. It gives isolation better than 38 dB over the entire bandwidth of the two frequency bands. The measured antenna gain is 7.5 dBi at S-band and 10.5 dBi at X-band.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.