Abstract: A multi-band planar antenna applicable as an internal antenna in small-sized mobile stations, and to a radio device including an antenna according to the invention. The basis is a conventional dual band PIFA with its feeding and shorting conductors and a non-conducting slot. The planar element (220) has a second slot (232) known as such, which starts at the edge of the planar element on the other side of the feeding conductor (221) and shorting conductor (211) than the above-mentioned slot (231). In addition the structure comprises a second shorting conductor (212) on the other side of the second slot, than the feeding conductor. The second slot acts as a radiator, which for instance broadens the upper band of a dual band antenna. The second shorting conductor facilitates a better matching of a multi-band antenna than in corresponding prior art antennas. The antenna is simple, and its manufacturing costs are relatively low.

Abstract: A planar antenna structure intended to be used in small portable radio devices and a radio device using an antenna structure according to the invention. The radiating element (340) of the antenna is a conductive part in the cover of the radio device or a conductive coating attached to the cover. The radiating element is fed electro-magnetically by a parallel planar feed element (330) connected to the antenna port and located near the radiating element, between it and the ground plane (310). Between the feed element and antenna port there is a feed circuit (320) to provide matching for the antenna and, if necessary, forming an additional operating band. The radiating element need not be shaped to set the resonating frequencies or match the antenna. Instead, it can be designed relatively freely, based on the desired external appearance of the device, for example. Moreover the antenna requires relatively little space within the device.

Abstract: A radiating antenna element intended to be used in small-sized radio devices, and a radio device having an antenna element according to the invention. The antenna element is part of the covers of a radio device. The antenna element may be conductive throughout, or it may comprise a dielectric portion and a conductive portion, which constitute a single integral component. The radiating portion of the antenna element is relatively large, e.g. in a foldable phone (20) the antenna element (200) may comprise the whole cover of a foldable part (21) except for the front side. The radiating element is advantageously fed electromagnetically through a feed element. As the radiating element is relatively large and is located on the outer surface of the device, the radiation characteristics of the antenna are good, and the space required by the antenna inside the device is relatively small.

Abstract: An internal multiband antenna intended to be used in small-sized radio devices and a radio device having an antenna according to the invention. The radiating element (330) of the antenna is a conductive part in the cover of the radio device or a conductive surface attached to the cover. The radiating element is fed electromagnetically by a feed element (320) connected to the antenna port. The feed element is designed (321, 322) such that it has, together with the radiating element and ground plane (310), resonating frequencies in the areas of at least two desired operating bands. In addition, the resonating frequency of the radiating element itself is arranged to fall into an operating band. Antenna matching is provided by feed element design and short-circuiting (315). The radiating element design can be based on the desired external appearance of the device, and the locations of the operating bands and antenna matching are provided through feed element design and short-circuiting.

Abstract: An internal multiband antenna and a radio device intended particularly for small-sized radio devices. The antenna has a relatively wide surface radiator (330), which is electromagnetically connected to the antenna port of the radio device via a separate feed element (320). At least two useful resonances are generated with the aid of the feed element, and at least one inherent resonance of the radiator is also utilized. The radiator has a hole (350), by which one useful additional resonance is generated. An oscillation is excited in the hole by placing the feed element close to its edge and by suitably choosing the locations of the feed point (F) and the shorting point (S) of the feed element. The frequency of the hole resonance is finely tuned by varying the capacitance between the hole's edge and the ground plane at a suitable place (331). An operating band of the antenna can be widened by means of said additional resonance.

Abstract: A multiband antenna applicable as an internal antenna in small mobile terminals especially. The antenna (200) is a PIFA placed inside the housing of a mobile station with at least two operating bands. A first resonance falling into a lower operating band is produced by means of a radiating conductive pattern (B21) in planar element (220). To improve the characteristics of the antenna in the upper operating band the planar element further comprises a slot (232) which goes between the feed point (F) and the short-circuit point (S) of the antenna. The radiator provided by this slot can be considered a quarter-wave slot radiator or a half-wave loop radiator. The PIFA further may have another radiator, which resonates in the upper operation band. By means of said slot the upper operating band of an antenna can be widened or the radiation in the horizontal plane in the upper operating band can be made more effective.

Abstract: An antenna intended to be used in a small and foldable radio device and a radio device which has an antenna according to the invention. The radiating element (120) in the antenna is a conductor having an outline shaped substantially like a rectangle and defining a plane which is perpendicular to the ground plane (GND) situated on the circuit board (111) of the radio device. The radiating element is so narrow that it fits inside the foldable device in the perpendicular position. The element is connected to the radio device only by its feed point (F). Resonating frequencies of the element can be arranged in desired locations besides by shaping the element, also by means of discrete components (L, C). The matching of the antenna is easily arranged by providing an appropriate distance between the radiating element and ground plane. In an operating situation, an antenna gain is achieved which is considerably higher than that of a PIFA of equal height.

Abstract: An antenna intended to be used in a small-sized and flat radio device, and to a radio device which has an antenna according to the invention. The base element of the antenna is a monopole-type conductor (110) internal to the device. This conductor may be designed such that the harmonic nearest to the fundamental resonating frequency can be utilized in providing an upper operating band. In addition to the base element the antenna structure comprises a parasitic element (120) which functions as both an auxiliary radiator and antenna matching element. Matching is optimized using an inductive component (125) which connects the parasitic element to signal ground. The antenna gain achieved is considerably higher than that of known antenna structures occupying the same space (h), and the antenna matching is improved, compared to known internal monopole antennas.

Abstract: A method for attaching an additional object to a resonator body. The method includes the steps of (1) placing the additional object in a recess of a pushing part of an extrusion machine; (2) pressing the pushing part against a bloom of a resonator body; and (3) pulling the pushing part back from the resulting resonator body. The attaching of the additional object occurs in conjunction with the extrusion process.

Abstract: The invention relates to a method for tuning dielectric antennas designed for operation especially in the microwave range, and an antenna structure. An antenna is tuned by removing material (211) from a dielectric block (210) located between conductive elements, whereby the resonance frequency of the antenna increases. The conductive elements (220, 230) on opposing surfaces of the dielectric block are advantageously shaped identical and located symmetrically with respect to each other so that the tuning of the antenna will not affect the other electrical characteristics of the antenna apart from the resonance frequency. With the method according to the invention there is no risk of producing conductive chips resulting from the working of metallic elements, the tuning of the antenna becomes accurate, and structural faults in the medium will be automatically compensated for.

Abstract: The invention relates to a multiband antenna which finds utility particularly in mobile stations. The antenna structure includes a PIFA-type antenna positioned inside the covers of a mobile station, which antenna includes a slot radiator (231). In the planar element there is a second slot (232) so that, viewed from a feed point (F), two radiating conductive branches (B1, B2) of different lengths are formed. Each of the three radiators has a separate operating band of its own. The structure also includes a whip element (211) movable with respect to the PIFA part. When the whip element is pulled out, its lower end is galvanically coupled with the shorter branch of the planar element, with its relatively narrow side branch (B12). The whip enhances the operation of the antenna especially in the lowest operating band. The influence of the pulled-out whip on the location of the uppermost operating band is compensated for by a third slot (233) in the planar element.

Abstract: An internal planar antenna for small radio apparatuses. The ground plane (310) of the planar antenna is shaped such that it improves the matching of the antenna. The shaping may be done by means of one or more slots (315, 316) in the ground plane. The slot suitably changes the electrical length of the ground plane as viewed from the short-circuit point (S) so that the ground plane will function as a radiator in an operating band of the antenna. Also the slot (331) in the ground plane can be arranged to function as an additional radiator in an operating band of the antenna. Antenna gain will increase as the matching is improved, and the upper band of a dual band antenna, for example, can be made broader.

Abstract: The invention relates to a method for attaching an additional object to an object made by the process of extruding, especially a resonator body, and to the structure resulting from the application of the method. A recess is made in the pushing part (ES) of an extrusion machine, which recess is shaped like a portion of the surface of the additional object. The additional object (320), such as a portion of the inner conductor of a resonator, is inserted prior to extrusion in the said recess so that the said portion of the surface of the additional object rests tightly against the surface of the recess and the rest of the surface of the additional object remains free. In the extrusion stage, the pushing part with the additional object is pressed (F) against a bloom of a resonator body whereby the material (31c) of the bloom is pressed tight against the free surface of the additional object. When the pushing part is retracted the additional object remains attached to the body element thus formed.

Abstract: A control system for the transmitting power of a multiband antenna of especially a mobile station. The antenna (300) has at least two radiating elements (B31, B32) corresponding to different operating bands. A separate part is arranged for each element in the antenna switch of a radio device using TDD technology. When one radiating element (B31) is connected to a transmitter (TX1), the other radiating element (B32) is connected to a control circuit (DET, PCU) for a radio-frequency power amplifier (PA1) of the transmitter. By an electromagnetic coupling (CP) between the radiating elements is then produced to the control circuit a signal (M1) indicating the transmitting power, and the transmitting power can be kept as desired by controlling the power amplifier. The electromagnetic coupling between the elements is arranged suitable in view of the power control.

Abstract: An adjustable planar antenna especially applicable to mobile terminals, and to a radio device provided with that kind of antenna. The basic structure of the antenna is PIFA. On a surface of a dielectric part (205) there is placed a strip conductor (230) so that this has a significant electromagnetic coupling to the radiating plane (220). The strip conductor can be connected by a switch (SW) to the ground plane. When the switch is closed, the electric length of the radiating plane is changed, measured from the short point (S). In which case also the antenna's resonance frequency is changed. The change depends on the place and the size of the strip conductor. In the case of a multi-band antenna the strip conductor can be placed so that it has a remarkable electromagnetic coupling to one or more radiating elements (B1, 226). The adjusting of planar antenna is performed by means of small additive components, which do not presume changes in the antenna's basic structure and do not enlarge the antenna.

Abstract: An arrangement for bypassing a low-noise amplifier (LNA), intended especially to be used in base stations of mobile networks. For the bypass, a receiver antenna filter (210) has a second output (OUT2) parallel with a first output (OUT1) connected to the LNA. The antenna filter is of the resonator type, and there is a conductive element for each of its outputs in the resonator cavity. Selection between the LNA output signal and signal coming direct from the antenna filter is made by a changeover switch (SW). The noise figure of the receiver front stage (220) will improve as the series switch on the signal path, which most degrades the noise figure, is removed between the filter and LNA, and isolation on the LNA bypass path increases.

Abstract: A double-action antenna structure includes, e.g. a PIFA-type antenna inside the casing of a mobile station, a coupling element and a moveable whip element. The coupling element is a relatively small conductive element between the radiating plane and ground plane of the PIFA, galvanically isolated from the radiating plane and ground plane. When the whip element is retracted, it has no significant coupling to the PIFA parts. When the whip element is extended, its lower end is galvanically connected to the coupling element so that a significant electromagnetic coupling is established between the whip element and the radiating plane of the PIFA. Thus the whip element is fed through the PIFA without being in galvanic contact with it. The coupling element further provides for the matching of the whip element. The internal and external antennas may be designed and optimized relatively independently of each other.

Abstract: An antenna of a radio apparatus, the directional pattern of which can be altered controllably. The antenna comprises at least one conductive element, additional from the viewpoint of the basic operation of the antenna, for shaping the directional pattern of the antenna. Such a conductive element (330, 340) is connected to signal ground at a ground point relatively near the feed point (F) of the antenna. The conductive element has a part (331) the length of which is about a quarter of the wavelength at an operating frequency of the antenna, pointing from the ground point (G) in a direction substantially opposite to the feeding direction of the radiating element (320). That part is used to equalize the directional pattern of the antenna in the receiving band. In addition, the conductive element has a second part (332) pointing from the ground point to the feeding direction of the radiating element to set a directional pattern notch at transmitting band frequencies in a desired direction.

Abstract: The invention relates to frame structures, particularly to mobile stations and other small-sized portable devices operating at high frequencies. The frame structure according to the invention is formed by extrusion, whereby the fixing means required for fastening components are formed into it during the extrusion. Such fixing means are preferably pin-like projections which can be compressed to a rivet fixing the component. Such fixing means can also be strip-like fixing edges which are bent over the component edges. With such fixing means it is possible to form at the same time both a mechanical fixing and a good electrical contact between the component and the frame structure. During the extrusion it is also possible to fasten to the frame structure parts made of other materials, such as fixing means of other types or other components, such as antennas.

Abstract: The invention relates to a method of manufacturing a structure suitable as an internal antenna in small radio devices, and an antenna element to which the method is applied. The antenna element comprises a radiating plane and additionally e.g. supportive elements, a feed conductor and short-circuit conductor as well as extensions to increase capacitance. The antenna element is fabricated by first extruding from a billet an antenna billet, and working the latter as required. The antenna billet may be symmetrical so that two antenna elements will be produced when it is cut in half. Advantageously the antenna element is fabricated so as to conform with the covering of the device in which it is placed. It may also be part of a covering of a device. The manufacturing costs of the antenna element are relatively low and the radio characteristics of the element are good. An antenna structure employing the element has got few separate parts and is mechanically firm and space-conserving.