Abstract: An antenna includes a substrate, a radiation portion, and a signal feed-in portion. The radiation portion includes a first radiation unit and a second radiation unit. The first radiation unit and the second radiation unit are disposed on the same surface of the substrate. The signal feed-in portion is disposed on the first radiation unit. The second radiation unit and the first radiation unit have the same shape and are symmetrical in position, and the second radiation unit is connected to the first radiation unit, such that the first radiation unit and the second radiation unit form a closed loop. Thus, the impedance is improved and a wider bandwidth is achieved.

Abstract: An inverted-F antenna includes a radiation element, a ground element, a loop conductive pin, a signal feed-in portion, and a signal line. The antenna is designed as the signal feed-in portion and the ground portion sharing a single pin, thus solving the problem of the conventional inverted-F antenna having complicated components and increased cost due to using two independent components in parallel including a conductive pin and a signal feed-in portion for grounding and receiving feed-in signals.

Abstract: A high gain omni-directional antenna includes a substrate, a signal feed-in portion, a first radiating unit, and a second radiating unit. The first radiating unit and second radiating unit respectively have a first radiation contact and a second radiation contact, for connecting the first radiating unit and the second radiating unit in series so as to form a circular closed loop. The high gain omni-directional antenna avoids the coupling effect between the signal line and the radiating end of the conventional high gain omni-directional antenna, and further solves the problem of excessively high directivity caused by the distance between the signal line and the radiating end. The design of the ring antenna of the high gain omni-directional antenna can raise the impedance and also realize a broader bandwidth.

Abstract: A method of inhibiting cross-polarization of a microstrip antenna and a device thereof. Increase of a microstrip antenna array not only increases co-polarization, but also increases cross-polarization. When the microstrip antenna is designed and fabricated, the fabricated antenna is tested first. That is, intensity distribution of the cross-polarization in a radiation frequency band is tested first, and a radiation frequency that the cross-polarization is corresponding change with is found out when an antenna radiation unit is broken. A slot is fabricated in the corresponding antenna radiation unit to break the symmetry of the antenna radiation unit, so as to effectively inhibit the cross-polarization without influencing the co-polarization of the antenna radiation unit at a corresponding radiation frequency.

Abstract: A slot-coupled microstrip antenna includes a first substrate, a second substrate, and a support base. The first substrate having a first surface and a second surface, in which a ground surface that is formed on the first surface, and a plurality of slots are formed on the ground surface. A feeding network is formed on the second surface. A plurality of antenna corresponding to the slots are formed on the second substrate disposed above the first surface. The support base having two fillisters at two side of the support base. The design of slot structure often has adverse influence on cross polarization and a front-to-back ratio of antenna radiation. The support base having two fillisters of the slot-coupled microstrip antenna can effectively inhibit the influence on the cross polarization and raise the front-to-back ratio from the slots.

Abstract: A phase shifter includes a metal plate, a support portion, a slot, a coupling portion, and a ground portion. The phase shifter effectively improves signal coupling efficiency, and inhibits noise generated with the change of phase shift due to signal transmission. The phase shifter is advantageous in smaller volume, easy to assemble, and low cost.

Abstract: An antenna structure including a ground plate, a hollow bolt, and a conductive conical dome is provided. The hollow bolt passes through the ground plate, and a signal wire is laid in the hollow bolt. An insulator is disposed between the signal wire and the hollow bolt for providing electrical isolation therebetween. The conductive conical dome is connected with one end of the signal wire. The hollow bolt and a nut are provided to fix the antenna on a wall or a ceiling. Since the signal wire is laid in the hollow bolt, the signal wire can be connected to a signal source only by connecting a signal cable to the hollow bolt.

Abstract: A dipole array directional antenna is integrally formed. The antenna includes two radiation portions, having a signal feed-in part and a ground signal feed-in part there-between, in which the signal feed-in part receives a feed-in signal, and each radiation portion radiates a radio-frequency (RF) signal corresponding to the feed-in signal; a ground portion, formed at an area adjacent to the ground signal feed-in part, and electrically coupled to the radiation portions; and two slots, respectively opened between each radiation portion and the ground portion, for matching a line impedance of the dipole array directional antenna.

Abstract: A symmetric-slot monopole antenna is provided, including a metallic board. Formed on the metallic board are a ground connection part to provide a ground circuit for the monopole antenna and a radiation part formed integrally on the ground connection part to receive and radiate signals transmitted through a signal cable.

Abstract: An antenna structure including a ground plate, a hollow bolt, and a conductive conical dome is provided. The hollow bolt passes through the ground plate, and a signal wire is laid in the hollow bolt. An insulator is disposed between the signal wire and the hollow bolt for providing electrical isolation therebetween. The conductive conical dome is connected with one end of the signal wire. The hollow bolt and a nut are provided to fix the antenna on a wall or a ceiling. Since the signal wire is laid in the hollow bolt, the signal wire can be connected to a signal source only by connecting a signal cable to the hollow bolt.

Abstract: A symmetric-slot monopole antenna is provided, including a metallic board. Formed on the metallic board are a ground connection part to provide a ground circuit for the monopole antenna and a radiation part formed integrally on the ground connection part to receive and radiate signals transmitted through a signal cable.