MULTI-RESONANCE ANTENNA, ANTENNA MODULE, RADIO DEVICE AND METHODS

• US 20130241779A1
• Filed: 01/12/2012
• Published: 09/19/2013
• Est. Priority Date: 01/25/2011
• Status: Active Grant

• Current Assignee: Pulse Finland Oy (Yageo Corporation)
• Original Assignee: Pulse Finland Oy (Yageo Corporation)
• Inventors: Korva, Heikki
• Granted Patent: US 9,203,154 B2
• Time in Patent Office: Days
• US Class Current: 343/700.MS
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 5/378 Combination of fed elements with parasitic elements
• CPC Class Codes: H01Q 9/04 Resonant antennas
• CPC Class Codes: H01Q 9/42 with folded element, the folded parts being spaced apart a small fraction of the operating wavelength

Abstract

An internal dual band antenna meant for small radio devices. In one embodiment, the antenna contains two radiators and a parasite element, which is shared between them. The parasite element is implemented on three sides of the antenna module, which are perpendicular to the side where the two radiators are implemented. The short-circuit conductor of the parasite element extends close to the supply point/points of the antenna on the circuit board of the radio device and is connected to the ground plane of the radio device. The antenna structure is dimensioned such that the two resonance frequencies on both functional bands are at a lower frequency than the resonance frequencies of the actual radiators. Accordingly, both the lower and upper frequency band is widened. The shape of the parasite element does not weaken the adaptation of the antenna in either functional band.

Claims

1-16. -16. (canceled)

17. A multiband antenna for use in a radio device, comprising:

a circuit board comprising a ground plane disposed on a first portion of the circuit board, the circuit board further comprising a second portion on which the ground plane is not disposed;

a dielectric component disposed on the second portion of the circuit board;

a first and a second radiating element resident on an upper surface of the dielectric component, the first and the second radiating elements configured to radiate at a lower and an upper frequency band, respectively; and

a parasitic element disposed on a plurality surfaces of the dielectric component that are perpendicular to the ground plane of the circuit board.

18. The multiband antenna of claim 17, wherein the first radiating element of the lower frequency band is configured to be supplied from a first supply point coupled to an antenna port of the radio device;

and

wherein the second radiating element of the upper frequency band is configured to be supplied from a second supply point coupled to the antenna port.

19. The multiband antenna of claim 18, wherein the parasitic elements are configured to widen the respective lower and upper frequency bands associated with the first and second radiating elements, respectively.

20. A multiband antenna for use in a radio device, comprising:

a circuit board comprising a ground plane;

a dielectric piece that is installed on a first end of the circuit board, the first end of the circuit board having the ground plane removed;

first and second monopole-type elements resident on an upper surface of the dielectric piece that radiate in separate frequency bands, the first and second monopole-type elements corresponding to lower and upper frequency bands, respectively;

a parasitic element that is electromagnetically coupled to the first and second monopole-type elements on at least one surface of the dielectric piece.

21. The antenna of claim 20, wherein:

the first monopole-type element of the lower frequency band is arranged to be supplied from a first supply point connected from an antenna port, the first monopole-type element together with other portions of the multiband antenna comprising a first resonator, the natural frequency of the first resonator being in said lower frequency band;

the second monopole-type element of the upper frequency band is arranged to be supplied from a second supply point connected from the antenna port, the second monopole-type element together with other portions of the multiband antenna comprising a second resonator, the natural frequency of the second resonator being in said upper frequency band.

22. The antenna of claim 21, wherein:

the parasitic element is grounded from a connecting point to the ground plane of the circuit board, the parasite element in combination with the other portions of the multiband antenna comprising a third resonator; and

both the lower frequency band and the upper frequency band have two resonance locations in order to widen their respective frequency bands, the resonance location associated with the lower frequency band being caused by the parasitic element and the resonance location associated with the upper frequency band being caused by the first and second monopole-type elements.

23. The multiband antenna of claim 20, wherein:

the electromagnetic coupling between the first and second monopole-type elements and the parasite element is formed at least in part by a predominantly inductive connection of a conductive strip departing from the connecting point of the parasitic element and the first and second monopole-type elements; and

the magnitude of the predominantly inductive connection being determined at least in part by a distance between the first and second supply points and the connecting point of the parasite element.

24. A multi-band antenna configured for use in a radio device, comprising:

a dielectric piece, which has a first surface;

a first and a second monopole-type elements that radiate on a lower and an upper band, respectively, with their supply points being resident on a second surface of the dielectric piece, the second surface being substantially parallel to the first surface;

a parasitic element on at least one surface of the dielectric piece, the parasitic element forming an angle in relation to the first and the second surface;

wherein the multi-band antenna is configured to provide on both the lower band and the upper band two resonance locations in order to widen the frequency range of the lower and upper bands; and

wherein the resonance of the lower functional band is caused by the parasitic element and the resonance of the upper band is the natural resonance of the first and the second monopole-type elements.

25. The multi-band antenna of claim 24, wherein the first monopole-type element of the lower band comprises a supply point on a first side of the multi-band antenna, a coil and a quarter-wave radiator comprising four conductor branches connected to the coil.

26. The multi-band antenna of claim 25, wherein the coil is configured to at least shorten the physical length of the first monopole-type element.

27. The multi-band antenna of claim 25, wherein the dielectric piece comprises a rectangular polyhedron.

28. The multi-band antenna of claim 27, wherein the second monopole-type element of the upper band comprises a supply point on the first side of the multi-band antenna and a quarter-wave radiator comprising three subsequent conductor branches in electrical communication with the supply point.

29. The multi-band antenna of claim 25, wherein the second monopole-type element of the upper band comprises a supply point on the first side of the multi-band antenna and a quarter-wave radiator comprising three subsequent conductor branches in communication with the supply point.

30. The multi-band antenna of claim 29, wherein the second monopole-type element of the upper band and the first monopole-type element of the lower band have a shared supply point on the first side of the multi-band antenna.

31. The multi-band antenna of claim 24, wherein the parasitic element comprises a U-shape, a bottom part of the U-shape being situated at an end side of the multi-band antenna, and one or more adjacent sides of the U-shape being situated in the direction of the longitudinal axis of the radio device.

32. The multi-band antenna of claim 31, wherein the parasitic element is divided at a connection point of a short-circuit conductor into a first branch and a second branch.

33. The multi-band antenna of claim 32, wherein the first and second branches of the parasitic element are disposed on a third and a fourth side of the multi-band antenna.

34. The multi-band antenna of claim 33, wherein a first resonance frequency of the lower band is defined by the length of the short-circuit conductor, and a second resonance frequency of the upper band is defined by the total length of the parasitic element.

35. The multi-band antenna of claim 34, wherein the first resonance of the lower band comprises a quarter-wave resonance, and the first resonance of the upper band comprises a half-wave resonance.

36. A radio device (RD), comprising:

at least one internal multi-band antenna having at least a first and a second functional band, said at least one internal multi-band antenna comprising a first monopole-type element configured to radiate on a lower frequency band and a second monopole-type element configured to radiate on an upper frequency band;

a parasite element electromagnetically coupled to the first and second monopole-type elements, the first and second monopole-type elements are coupled to one or more supply points connected to an antenna port of the radio device, said parasite element being coupled from a first short-circuit point to a ground plane of the radio device;

wherein the first monopole-type radiating element of the lower frequency band is arranged to be supplied from the at least one supply point connected to the antenna port, the first monopole-type radiating element together with the other parts of the multi-band antenna comprising a first resonator, the natural frequency of the first resonator being in said lower frequency band;

wherein the second monopole-type radiating element of the upper frequency band is arranged to be supplied from the at least one supply point connected to the antenna port, the second monopole-type radiating element comprises a second resonator, the natural frequency of the second resonator being in said upper frequency band;

wherein the parasite element is grounded only from a connecting point to the ground plane of the circuit board, the parasite element together with the surrounding antenna parts comprising a third resonator; and

wherein both the lower frequency band and the upper frequency band have two resonance locations in order to widen the functional band, the resonance associated with the lower frequency band being caused by the parasite element and the resonance associated with the higher frequency band being caused by the first and second monopole-type elements.

37. The radio device of claim 36, wherein the parasite element comprises a U-shape, the bottom part of the U is on the side constituting a first outer end of the radio device and the parasite element is divided at a connection point of a short-circuit conductor into a first branch and a second branch, the arms of the branches of the parasite element being on a third and a fourth side of the radio device.

38. The radio device of claim 36, wherein the internal multi-band antenna comprises two parallel mounted multiband antenna components configured to comprise a diversity antenna system.