Abstract: A communication device with an RF (Radio Frequency) node and a detection node includes a first radiation element, a second radiation element, a first inductor, a second inductor, a third inductor, a first capacitor, and a second capacitor. The first radiation element is coupled to a first node. The second radiation element is coupled to a second node. The first inductor is coupled between the RF node and the ground voltage. The first capacitor is coupled between the RF node and the first node. The second inductor is coupled between the first node and the second node. The second capacitor is coupled between the second node and the ground voltage. The third inductor is coupled between the detection node and the second node. An antenna structure and a sensing pad are formed by the first radiation element and the second radiation element.

Abstract: A communication device with an RF (Radio Frequency) node and a detection node includes a first radiation element, a second radiation element, a first inductor, a second inductor, a third inductor, a first capacitor, and a second capacitor. The first radiation element is coupled to a first node. The second radiation element is coupled to a second node. The first inductor is coupled between the RF node and the ground voltage. The first capacitor is coupled between the RF node and the first node. The second inductor is coupled between the first node and the second node. The second capacitor is coupled between the second node and the ground voltage. The third inductor is coupled between the detection node and the second node. An antenna structure and a sensing pad are formed by the first radiation element and the second radiation element.

Abstract: A wearable device includes a nonconductive back cover, a metal loop, a PCB (Printed Circuit Board), a feeding element, and a shorting element. The nonconductive back cover substantially has a hollow structure. The metal loop is disposed on the nonconductive back cover. The metal loop has a feeding point and a grounding point. The PCB is disposed inside the nonconductive back cover. The PCB includes a ground plane. A signal source is coupled through the feeding element to the feeding point of the metal loop. The grounding point of the metal loop is coupled through the shorting element to the ground plane. An antenna structure is formed by the metal loop, the feeding element, and the shorting element.