KR100626815B1 - Antenna Means for Portable Wireless Communication Devices - Google Patents

Abstract

Antenna means for portable radiocommunication devices, in particular hand portable mobile phones, have at least one radiating element which is meandering and has a cylindrical arrangement. This structure is advantageous when combined with an elongate and retractable whip antenna and has two or more meandered radiating elements in a multiband radiating structure. For example, a flexible printed circuit board technology is suitable for the antenna device in mass production.

Description

Antenna means for portable radio communication device

TECHNICAL FIELD The present invention relates to antenna means, and more particularly to antenna means for a portable mobile phone in which a compact and efficient antenna is required. In particular, the antenna means of the present invention is useful when two or more radiating elements are combined or an impedance matching means for matching the radiating elements of the antenna means to the transmitting / receiving circuit of the telephone is required.

A common problem with antenna radiators is that their bandwidth decreases as their size decreases. In general, a spirally arranged radiator is used when it is required to install an antenna within a limited volume with a limited height. However, the loop of the helical antenna creates a magnetic field that combines energy which further reduces the bandwidth. Helical radiators also have the problem of strong mutual coupling when two or more radiators are arranged adjacent to each other.

GB-A 2 208 789 discloses an antenna means having a plurality of curved portions formed by conductive radiating elements formed on a dielectric substrate. The substrate may be tubular with conductive strips on one side, the strips being joined together along the opposite edge of the tubular substrate. In another embodiment, the substrates have conductor strips that are flat and stacked on both sides, and the strips are joined together by feed-through along opposite edges of the substrate. Prior art antenna devices have the inherent disadvantages of helical antennas and are therefore difficult to manufacture and complicated by the need to form through holes in the substrate or to join conductors at the edges.

Despite being relatively efficient and compact, the antenna devices according to the various prior arts contain the problems mentioned above due to the use of helical radiators. Such antenna devices are disclosed, for example, in European Patent Publication Nos. 0 635 898 A1 and 0 593 185 A1 and 0 467 822 A2, PCT Publications WO94 / 10720 and WO95 / 08199 and US Pat. No. 4,868,576. It is.

Conventionally, a meandering antenna has been used when an antenna device having a shorter overall length than the operating wavelength of an associated transmitter / receiver is required. In DE-A1 31 29 045, for example, a direction finder antenna having a meandering structure is disclosed. Here, the radiating element is mounted on the dielectric carrier with a meandering arrangement.

DE-A1 31 29 045 may be considered to disclose the prior art antenna device closest to the present invention. Here, the problem to be solved is to reduce the height of the orientation finder antenna, in particular to be able to hide and move. However, only the meandering antenna having a flat panel arrangement is disclosed here. Moreover, the principle is to improve the bandwidth of the antenna by using a conductor having a relatively high resistance, resulting in a lower efficiency antenna. Moreover, there is no provision for obtaining an antenna with mechanical durability or an antenna suitable for installation in a limited volume, or an antenna combined with another type of antenna.

Another planar meandering antenna element is disclosed in the summary of Japanese Patent Laid-Open No. 6-90108 and includes a meandering dipole and matching means connected to a coaxial transmission line. In addition, a meandering feeder for a spiral antenna is disclosed in US Pat. No. 5,298,910. In the latter two devices, the transmission line is not connected to the tip of the meander conductor.

Pending Swedish patent application 9601706-6 includes means integrated with the antenna for matching the antenna to the circuit of a portable mobile phone, and similar matching means in the present invention are also suitable. Therefore, the Swedish patent application is referred to herein.

SUMMARY OF THE INVENTION An object of the present invention is to provide an efficient antenna means, and to solve the problem in providing an antenna means having a geometric shape that is mechanically durable and suitable to be placed in a small volume.

Another object of the present invention is to provide a substitute for a helical radiator that provides improved antenna performance, and to overcome the above problem of coupling electromagnetic energy in the radiator or radiators of the antenna means, Through-holes can be avoided in the receiving carrier, an efficient and cost effective impedance matching means integrated with the antenna means can be provided, and an efficient and mechanically durable arrangement can be provided, e.g. More accurate production techniques, such as spirals, can be used, and in particular to provide antennas in which other radiating elements can be combined without a reverse mutual coupling in combinations including extensible whip antennas.

1A to 1B illustrate a portable mobile telephone having an antenna means according to various basically similar embodiments of the present invention in which a meandering conductor extends in a cylindrical shape and protrudes from a chassis of a telephone equipped with a whip antenna capable of extension and contraction. Shown,

2a to 2c show another possible meandering conductor arrangement provided on the flexible film carrier according to the invention,

2D illustrates a flexible film carrier containing meandering conductors formed in a cylindrical arrangement used to replace helical conductors in various antenna applications;

3a to 3b are double meandering conductors tuned to different frequencies on a common flexible film carrier providing dual band operability of the antenna means according to the invention and fed separately or via a common feed point; Drawing,

4 shows the combination of a meandering conductor with a cylindrical arrangement and a whip antenna capable of extension and contraction;

5 shows a combination of a meandering conductor having a cylindrical arrangement and a whip antenna capable of extension and contraction, wherein the meandering conductor and the whip antenna are respectively matched to the impedance on the transmitter / receiver of the mobile telephone. Figure showing that the impedance matching means is provided in the flexible film carrier of the sieve,

FIG. 6 shows another combination of meandering conductors with a cylindrical arrangement and a whip antenna capable of extension and contraction, showing that the meandering conductor and the whip antennas are connected in series when the whip antenna is in an extended position;

FIG. 7 illustrates another combination of the meandering conductor and the whip antenna capable of extension and contraction, wherein the coaxial transmission line is connected to the meandering conductor and the whip antenna, respectively; FIG.

8 illustrates a combination of a meandering antenna and a whip antenna capable of extension and retraction when the whip antenna is in a retracted position;

9 shows a slightly different combination from FIG. 8 when the whip antenna is in the retracted position;

10A and 10B illustrate another combination of a meandering antenna and a whip antenna that can be extended and retracted, showing that the upper portion of the whip antenna can be conductively connected or not connected while receiving the meandering conductor. .

The present invention for achieving the above object is tuned to the first frequency, and has a first axis in the central longitudinal direction, the first and second ends are respectively the first feed point (17; 20) and the first open end meandering A radial first element (14; 18) in the arrangement; A radiation second tuned to a second frequency different from the first frequency and having a second axis in the central longitudinal direction, the first and second leading ends being the second feed point 18 and 21 and the second open end, respectively, and also meandering; An antenna means comprising elements 15 and 19, wherein the antenna means are operable to operate within the first and second frequency bands near the first and second frequencies, respectively; Portable elements, characterized in that the two elements 15 and 19 extend alternately in the positive and negative angular directions with respect to the first axis, and the meandering curve of each radiating element is adapted to change the circumferential direction at least once along its length. Achieved by an antenna means for the communication device 4.

It can be found that the geometry of such a radiator has particular advantages in terms of stability, bandwidth and radiation characteristics. Since the radiation first element of the antenna means is an arcuate or curved meandering conductor, it occupies a space similar to the space occupied by the spiral radiation element. This arrangement allows the antenna means according to the invention to be used in most applications of radio communication devices for mobile telephones, in particular in which conventional spiral antennas have been used. In comparison with a helical antenna, the advantages of using the antenna device of the present invention are, for example, greater bandwidth, improved manufacturing tolerances resulting in less waste and certain adjacent radiators which greatly improve multiband operability. A low degree of coupling, and the possibility of integrating an impedance matching network on the same carrier, at least in part, with the same production technology. Radiating elements extending alternately in the positive and negative angular directions with respect to the central axis thereof, preferably extend along the longitudinal axis of the virtual cylindrical frame having a round or oval base, at least once in the circumferential direction. It can be understood as including a radiating element that draws a varying meandering curve.

When the antenna means comprise one or more additional radiating elements, operability in a wider frequency band or in two or more separate frequency bands is achieved. It is possible to produce all spinning elements simultaneously in the same sequence of processing steps.

When the limitation of the electromagnetic energy boundary in the radiating structure is of particular importance, it may comprise no arrangement at all, preferably only an arrangement which represents a small part of the entire rotation about the central axis.

The first and second feed points may be interconnected and may be commonly coupled to the circuitry of the wireless communication device. This can also be applied when two or more spinning elements are used. On the other hand, other radiation elements may be individually connected to the radio circuit.

Preferably, the antenna device comprises a dielectric carrier for receiving a radiation structure, which projects outward from the chassis of the wireless communication device on which the device is mounted. This enables an effective radiation pattern. Preferably, the carrier is a flexible film or lysate of a dielectric having a radiating structure applied to its surface or inside thereof in the form of a conductive film structure, possibly obtained through etching. In addition, printing technology is suitable for production of mass production.

As can be seen from the following description of this embodiment, the antenna means according to the invention is useful for coupling to a whip antenna which is capable of extension and contraction. Here, the carriers and conductors of the antenna means may comprise one or more switches for connecting or disconnecting the other radiating elements, possibly in different modes of operation.

In particular, when the carrier is a flexible film with a printed circuit pattern, an impedance matching means for matching the impedance of a given radiation element on the film may be integrated on the carrier, or the structure and the circuit of the radio communication device may be combined. Usually interfaced at 50 ohms.

Hereinafter, each embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

Referring to FIG. 1A, the meandering radiation element 1 is accommodated in the cylindrical dielectric carrier 2 and mounted so as to extend outward on the chassis 3 of the portable mobile telephone 4. The position of the meandering element 1 on the chassis 3 is selected so that the radiation of the meandering conductor 1 is effectively transmitted / received to another position selected by the operator while waiting or making a telephone call. 1A and 1B, the meandering element is located on one side of the upper part of the chassis 3 which protrudes upwards.

In addition, Figure 1a shows the position where the whip antenna (5) that can be extended and contracted is extended. Depending on the antenna performance required in certain cases, the whip antenna may or may not be coupled with the meander element. FIG. 1B shows the device of FIG. 1A with a whip antenna in its retracted position. FIG.

FIG. 2A shows a first possible form 6 of a meandering radiating element which is a conductor pattern etched on a dielectric flexible film carrier 7 in a plate arrangement. The spinning element consists of alternating curves comprising parallel parts and semicircular bends, and the free end of the opposite edge of the carrier 7 from the feed point 8 of one edge of the carrier 7 having a basically rectangular shape ( 9). The single meandering spinning element is also formed in a flat plate arrangement and, as shown below, also in a configuration in which the carrier 7 forms a tubular or at least a portion of a cylindrical shape.

2b and 2c show the second and third different shapes 10 and 11 of the meandering element, each having a rectangular and serrated shape, with corresponding reference numerals, similar to the shape of the meandering element of FIG. 2a. The furnace is formed together with the carrier 7 and extends from its surface.

2D shows a preferred cylindrical arrangement in which the meandering element 12 and the flexible film carrier 13 are formed together. This arrangement provides a compact and high durability. It can basically be used in most antenna applications where the space occupied by the helical antenna is available, especially when higher performance than the helical radiating element is required. On the other hand, the flexible film carrier can be replaced with another dielectric carrier, preferably having a cylindrical shape with some suitable cross section where the meandering conductor can be applied or deployed by high precision techniques such as etching. The arrangement as shown in FIG. 2D has an imaginary central axis, where the relative angle of the arcuate meandering element 12 is alternately increased and decreased with respect to this axis.

Referring to Fig. 3a, there are two meandering elements 14, 15 on a common carrier 16, which are two different ones which enable the operation of the antenna means in two overlapping or two separate frequency bands. Tuned to frequency. This element is powered by a common feed point 17, possibly coupled to the circuit of the portable mobile telephone via impedance matching means (not shown). It is also possible for two or more meandering elements to be arranged together to achieve operability in a wider band than achieved by two or more frequency bands or two elements. In FIG. 3A, despite the well-functioning flat plate arrangement, the flexible film carrier of the multi meandering means is preferably formed in the cylindrical arrangement as described above for a single meander element.

The degree of coupling between individual elements is much smaller for meander elements than for spiral elements that represent the same or comparable geometric separation, so that meander elements have a greater advantage over spiral elements for operation in separate or wider frequency bands. It is shown by the calculations and confirmed by simulation and testing.

FIG. 3B illustrates another example of the feeding arrangement of FIG. 3A. Here, each individual element 18, 19 has a respective feed point 20, 21 which can be individually coupled to the telephone circuit via the impedance matching means.

With reference to FIG. 4, the combination is a cylindrically disposed meandering radial element 22, with one point being the feed point 24 and the other being the free end 25, received by the cylindrical flexible film 23 carrier, whip When the antenna 26 is extended, it has a stopper 27 at the lower end applied to contact the feed point 24 of the meandering element via the contact member 28, and the whip antenna 26 is disposed at the opposite tip 29. It is shown to include an extendable conductive whip antenna 26 having an elongated dielectric portion 30 terminated by the knob 31 for support when sliding.

Basically, since the length of the long dielectric portion 30 is equal to the length of the meander element 22 arranged in a cylindrical shape, the whip antenna 26 does not extend with the meander element 22 in the retracted position (FIG. 8). Shown in).

In Fig. 4, the radiators 22 and 26 of the antenna means are preferably of the same type in both half wave and quarter wave form, for example.

In general, whilst higher antenna performance is required, such as during a telephone call, for example, the whip antenna is extended to contact the feed point of the meander element via the contact member, and the meander element and whip antenna are parallel to the telephone circuit. Connected. In this arrangement, the whip antenna affects most antenna functions. It is also possible to provide an antenna of the type with more complicated switching means which completely disconnect from one of the elements when not needed.

Fig. 5 shows a general method of placing the integrated impedance matching means 32 on the dielectric carrier 33 of the antenna device according to the invention. The matching means 32 is connected to the feed point 34 of the meander element 35 and comprises reactive elements 36 and 37 (shown schematically) and connection terminals 38 for telephone signals and ground connectors (not shown). 39).

Preferably, the apparatus of FIG. 6 has a basically half-wavelength extension with a quarter wave meander element 40 on a cylindrical carrier 41 and a long portion 43 of the dielectric mounted on top 44. Whip antenna 42 capable of contraction is included. This arrangement is more than the arrangement of FIG. 4 in that the top of the meander element 40 is conductively and capacitively fed at the bottom 45 of the whip antenna 42 when the whip antenna 42 is in the extended position. different.

Preferably, the device of FIG. 7 is basically quarter wave with a quarter wave meander element 46 on a cylindrical carrier 47 that is cylindrical and an elongated portion 49 of the dielectric mounted on top 50. A whip antenna 48 capable of extension and contraction. This arrangement allows the internal conductor 51 of the (coaxial) transmission line 51 at the position where the whip antenna 48 is extended so that the whip antenna (conductively and capacitively) is at the lower end 53 of the whip antenna 48. 48, and while the lower end 56 of the meander element 46 is an open end, the upper end 54 of the meander element 46 is driven by a shield 55 of the transmission line 52. It is further different from the arrangement of FIG. 4 in that it is fed.

As shown in FIG. 8, the whip antenna 57 is retracted in a situation where a more compact antenna means is required. The whip antenna 57 then provides a low or very small antenna function, while the meandering element 58 transmits / receives radiated power to the phone. Here, the dielectric portion 59 extends along the entire axial length of the meander element 58, so it is separated at the retracted position.

On the other hand, as shown in Figure 9, in order to reduce the storage depth required in the chassis of the portable mobile phone, the whip antenna 60, even in the position where the whip antenna 60 is retracted meander element 61 is arranged in a cylindrical shape ) May extend at least partially. In this case, the long dielectric portion 62 only partially extends along the meander element 61 when the whip antenna is retracted.

10A and 10B show the retracted and extended positions, respectively, with the whip antenna 63 receiving the meandering element 65 at the upper end 64. The conductive sleeve 66 constitutes a connection point to the telephone circuit (or matching means). By the presence of conductive connections between the whip and the meandering elements, they are in contact with the sleeve 66 at the portion 64 when deflated and the portion 67 when extended, or only the meandering element 65 as there is no conductive contact. The sleeve 66 is contacted in the retracted position and only the whip antenna 63 is in contact with the sleeve 66 in the extended position.

If more than one meandering element is included, various multiband antenna means can be constructed according to the above principles with reference to FIGS. 4 to 10.

Although the invention has been described in connection with a number of preferred embodiments, various modifications are possible without departing from the spirit of the invention as defined by the claims. One of these possible variations provides a power feeding means and a feeding arrangement different from that shown in FIGS. 4 to 10.

Claims (17)

A radiating first element 14 tuned to the first frequency and having a first axis in the central longitudinal direction, the first and second ends being the first feed point 17 and 20 and the first open end, respectively, in a meandering arrangement; 18); A spinning agent tuned to a second frequency different from the first frequency, having a second axis in the central longitudinal direction, the first and second leading ends being the second feed point 18 and 21 and the second open end, respectively, in a meandering arrangement; 2 elements (15; 19) are configured, An antenna means adapted to operate within a first and a second frequency band near a first and a second frequency, respectively, The first element 14; 18 and the second element 15; 19 extend alternately in the positive and negative angular directions with respect to the first axis, and the meandering curve of each radiating element extends at least once in the circumferential direction along its length. Antenna means for a portable radio communication device (4), characterized in that for changing. The antenna means of claim 1, wherein the radiating element does not comprise a full rotation about the central axis. 3. Antenna means for a portable radio communication device according to claim 1 or 2, characterized in that the first and second feed point (17) are interconnected. 3. The apparatus as claimed in claim 1 or 2, further comprising a dielectric carrier (2; 16; 23; 33) for receiving the radiation element and mounted on the radio communication device (4) such that the radiation element protrudes outward. An antenna means for a portable wireless communication device characterized in that. 5. A carrier according to claim 4, wherein the carriers (2; 16; 23; 33) have a carrier surface, And antenna elements (14, 15; 18, 19) formed by a conductive film provided on the carrier surface. 5. The portable radio according to claim 4, wherein the carriers (2; 16; 23; 33) are flexible dielectric films having thereon printed conductive films constituting the radiating elements (14,15; 18,19). Antenna means for communication device. 7. Antenna means according to claim 6, characterized in that the dielectric film (2; 23; 33) is substantially in the form of a cylindrical wall or part of a cylindrical wall. The antenna means of claim 1, wherein the element having a meandering arrangement is shaped to correspond to at least a portion of the cylindrical wall. 2. A portable radio communication device according to claim 1, wherein the whip antenna (5; 26; 42; 48; 57; 60; 63), which can be extended and retracted, can be operated in combination with an element having a meandering arrangement. Antenna means for. 10. A meander arrangement (22; 35) is secured to the chassis of a radio, and a whip antenna (5; 26; 42; 48) is capable of sliding through the element. Can be; When the whip antenna is in the retracted position, the element with the meandering arrangement is coupled to the circuitry of the radio, And the whip antenna is coupled to the circuit when the whip antenna is in an extended position. 10. The device of claim 9, wherein the whip antenna 63 is capable of sliding in and out of the chassis of the radio. An element 65 with a meandering arrangement is fixed coaxially to one end of the whip antenna and is always located outside of the chassis, When the whip antenna is in the retracted position, the element with the meandering arrangement is coupled to the circuitry of the radio, And an antenna having a meandering arrangement and a whip antenna in series with the circuit when the whip antenna is in an extended position. 10. The device of claim 9, wherein the whip antenna 63 is capable of sliding in and out of the chassis of the radio. An element with meander arrangement 65 is fixed coaxially to one end of the whip antenna and is always located outside of the chassis, When the whip antenna is in the retracted position, the element with the meandering arrangement is coupled to the circuitry of the radio, And the whip antenna is coupled to the circuit when the whip antenna is in an extended position. The element according to claim 9 or 10, wherein the element with a meandering arrangement, preferably essentially quarter-wave characteristic, is fixed to the chassis of the radio, through which the element is preferably basically half-wave characteristic. Extendable and retractable whip antennas that can slide, When the whip antenna is in the retracted position, the element with the meandering arrangement is coupled to the circuitry of the radio, 10. Antenna means for a portable radio communication device, characterized in that when the whip antenna is in an extended position, the whip antenna is preferably capacitively coupled to the circuit via the upper end of the element having the meandering arrangement. The whip antenna 48 according to claim 9, wherein an element 46 having a meandering arrangement is fixed to the chassis of the radio, and the whip antenna 48 capable of extending and contracting through the element 46 is slidable. When the whip antenna 48 is in the retracted position, an element with meander arrangement 46 is coupled to the circuitry of the radio at the top via a transmission line 52 extending through the element, An antenna means for a portable radio communication device, characterized in that when the whip antenna is in an extended position, it is coupled to the circuit at the bottom via the transmission line (51). 11. The device of claim 9 or 10, wherein an element having a meandering arrangement is secured to the chassis of the radio, wherein the whip antenna capable of extension and contraction is slidable through the element, When the whip antenna is in the retracted position, the element with the meandering arrangement is coupled to the circuitry of the radio, When the whip antenna is in the retracted position, the whip antenna is separated from the circuitry and extends at least partially inside the element with the meandering arrangement to reduce the depth of extension to the radio. Antenna means for. 5. Antenna means for a portable radio communication device according to claim 4, further comprising an impedance matching means (32) integrated on the dielectric carrier for matching the impedance of the radiating element to the circuit of the radio communication device. The method of claim 1, further comprising at least one radiation element that is similar to the first and second elements but has a meandering arrangement, but tuned to a third frequency different from the first and second frequencies. Antenna means for a portable wireless communication device.