An antenna structure with wide radiation bandwidth in a reduced physical space includes a housing, a connection capacitor, and a feed portion. The housing defines at least one gap and a slot dividing the housing into a first radiation portion, a second radiation portion, and a third radiation. The connection capacitor bridges the first gap, connecting the first radiation portion and the second radiation portion. The feed portion is electrically connected to the first radiation portion. The current flows through the first radiation portion and towards the second radiation portion through the connection capacitor. The current is further coupled to the third radiation portion to generate radiation signals in different frequency bands.

An antenna structure with wide radiation bandwidth in a reduced physical space includes a housing, a connection capacitor, and a feed portion. The housing defines at least one gap and a slot dividing the housing into a first radiation portion, a second radiation portion, and a third radiation. The connection capacitor bridges the first gap, connecting the first radiation portion and the second radiation portion. The feed portion is electrically connected to the first radiation portion. The current flows through the first radiation portion and towards the second radiation portion through the connection capacitor. The current is further coupled to the third radiation portion to generate radiation signals in different frequency bands.

An antenna for use in a distributed antenna system is provided. The antenna includes: (a) a feeding circuit on a first side of a first dielectric defining an edge perpendicular to the first side, a coplanar waveguide comprising a signal feed and a signal return coplanar with and interfittedly apart from the signal feed; (b) a radiator circuit on a second side of a second dielectric, a monopole radiator and a radiator return being copolanar and spaced apart from each other, the first dielectric capacitively coupling the signal feed to the monopole radiator; and (c) an edge connection along the edge for electrically connecting the signal return to the radiator return.

A cover encloses the feeding circuit, including its impedance matching, in a water-resistant enclosure. The antenna ceiling-mounts indoors, is coated with a fire-resistant coating, and is operable at VHF (132-174 MHz), UHF (350-520 MHz), and 698-960 MHz.

An antenna for use in a distributed antenna system is provided. The antenna includes: (a) a feeding circuit on a first side of a first dielectric defining an edge perpendicular to the first side, a coplanar waveguide comprising a signal feed and a signal return coplanar with and interfittedly apart from the signal feed; (b) a radiator circuit on a second side of a second dielectric, a monopole radiator and a radiator return being copolanar and spaced apart from each other, the first dielectric capacitively coupling the signal feed to the monopole radiator; and (c) an edge connection along the edge for electrically connecting the signal return to the radiator return.

A cover encloses the feeding circuit, including its impedance matching, in a water-resistant enclosure. The antenna ceiling-mounts indoors, is coated with a fire-resistant coating, and is operable at VHF (132-174 MHz), UHF (350-520 MHz), and 698-960 MHz.

An antenna system, such as a multifeed antenna system, can include at least one antenna feed element. The antenna system can include an antenna loop element. The at least one antenna feed element can be capacitively coupled to the antenna loop element. The at least one antenna feed element can include one or more capacitively coupled regions. The one or more capacitively coupled regions can form at least a portion of the capacitive coupling of the at least one antenna feed element to the antenna loop element.

A high-gain digitally tuned antenna system comprises a modified swept-back fractal (MSBF) radiator element, with the fractal preferably being a Sierpinski carpet fractal based on a parallelogram. A digital tuning circuit coupled to the radiator comprises an array of inductors which can be selectively connected to form a network which tunes the antenna system to a selected tuning frequency. The system is preferably arranged to selectively connect the inductors in series such that the combined inductances substantially cancel the capacitance of the radiator at a selected tuning frequency. The antenna system is preferably arranged to operate over the 30-88 MHz, 108-174 MHz, and 225-600 MHz bands, with a radiator height of 15″ or less.

A high-gain digitally tuned antenna system comprises a modified swept-back fractal (MSBF) radiator element, with the fractal preferably being a Sierpinski carpet fractal based on a parallelogram. A digital tuning circuit coupled to the radiator comprises an array of inductors which can be selectively connected to form a network which tunes the antenna system to a selected tuning frequency. The system is preferably arranged to selectively connect the inductors in series such that the combined inductances substantially cancel the capacitance of the radiator at a selected tuning frequency. The antenna system is preferably arranged to operate over the 30-88 MHz, 108-174 MHz, and 225-600 MHz bands, with a radiator height of 15″ or less.

A matching circuit for an antenna of whatever type, includes a ground circuit and a feed circuit. The ground circuit connects a ground terminal of the antenna to a ground voltage, and provides an inductive impedance between the ground terminal and the ground voltage. The feed circuit connects a feed signal to a feed terminal of the antenna. The feed circuit is capable of switching between a first mode and a second mode for respectively providing a first equivalent impedance and a second equivalent impedance between the feed signal and the feed terminal. An associated method is also disclosed.

A matching circuit for an antenna of whatever type, includes a ground circuit and a feed circuit. The ground circuit connects a ground terminal of the antenna to a ground voltage, and provides an inductive impedance between the ground terminal and the ground voltage. The feed circuit connects a feed signal to a feed terminal of the antenna. The feed circuit is capable of switching between a first mode and a second mode for respectively providing a first equivalent impedance and a second equivalent impedance between the feed signal and the feed terminal. An associated method is also disclosed.

The described system refers to a Sharkfin wireless device comprising a radiating structure, a feeding system and an external port, the radiating structure comprising at least a radiation booster, a ground plane layer and a conductive element that connects at least one the radiation booster to the ground plane layer. The radiating system arrangement features reduced dimensions and multiband operation including low-frequency bands like LTE700.