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As wireless technologies continue to advance, the collocation of diverse antennas operating at different frequency bands has become a common practice in various deployed communication platforms. However, antenna co-location introduces significant challenges, primarily in the form of substantial mutual interference among the antennas. In this article, we explore the integration of two cylindrical dielectric resonator antennas (DRAs) operating at distinct frequency bands, specifically 3.5-3.9 GHz and 6.0-6.4 GHz, designed for uplink and downlink communication with satellites. These DRAs are nested concentrically, resulting in a dual-band shared-aperture DRA. However, the performance of this configuration is significantly compromised due to the interaction between the two DRAs. To mitigate these interferences, two novel approaches are developed to suppress cross-band scattering and coupling, respectively. As a consequence, radiation patterns are restored and port isolations are improved. Subsequently, a prototype of the dual-band shared-aperture DRA was designed, fabricated, and tested. The measured results validate the effectiveness of these innovative interference mitigation techniques. The developed dual-band shared-aperture DRA represents a promising solution for installation on unmanned aerial vehicles (UAVs) to facilitate satellite communication.

We present a dual-band cylindrical Dielectric Resonator Antenna (DRA) having a shared-aperture configuration for satellite communication platforms. In order to mitigate cross-band interference, two innovative techniques are developed to improve radiation patterns and port isolation. A prototype of this dual-band DRA was designed, fabricated, and tested, showing promising results. This compact and efficient design is particularly suitable for Unmanned Aerial Vehicles (UAVs), offering a new solution for satellite communication systems.

The idea of designing a `sensing string' is presented in this paper. This,sensing string' is a hand-crocheted textile based strain sensor which can be used to measure the in-plane or out-of-plane large strain (up to 40\%, which depends on the fabric structure) at high temperature (up to 400 degrees C). The sensing mechanism is investigated theoretically by using a circuit network to analyse the key sensing elements contributing to the fabric sensor, and it is then validated experimentally to obtain the guidelines for the design of high performance strain sensors. It is found that the contact resistance between two contacting yams is the key factor dominating the sensing mechanism. The fabric density, which determines the number of contacting points within a given length, is proved to be the most important factor governing the sensitivity, repeatability, hysteresis, linearity and strain range of the sensor. Temperature exhibits a greater effect on the magnitude of the initial resistance of the sensor.

The idea of designing a `sensing string' is presented in this paper. This,sensing string' is a hand-crocheted textile based strain sensor which can be used to measure the in-plane or out-of-plane large strain (up to 40\%, which depends on the fabric structure) at high temperature (up to 400 degrees C). The sensing mechanism is investigated theoretically by using a circuit network to analyse the key sensing elements contributing to the fabric sensor, and it is then validated experimentally to obtain the guidelines for the design of high performance strain sensors. It is found that the contact resistance between two contacting yams is the key factor dominating the sensing mechanism. The fabric density, which determines the number of contacting points within a given length, is proved to be the most important factor governing the sensitivity, repeatability, hysteresis, linearity and strain range of the sensor. Temperature exhibits a greater effect on the magnitude of the initial resistance of the sensor.

The idea of designing a `sensing string' is presented in this paper. This,sensing string' is a hand-crocheted textile based strain sensor which can be used to measure the in-plane or out-of-plane large strain (up to 40\%, which depends on the fabric structure) at high temperature (up to 400 degrees C). The sensing mechanism is investigated theoretically by using a circuit network to analyse the key sensing elements contributing to the fabric sensor, and it is then validated experimentally to obtain the guidelines for the design of high performance strain sensors. It is found that the contact resistance between two contacting yams is the key factor dominating the sensing mechanism. The fabric density, which determines the number of contacting points within a given length, is proved to be the most important factor governing the sensitivity, repeatability, hysteresis, linearity and strain range of the sensor. Temperature exhibits a greater effect on the magnitude of the initial resistance of the sensor.