KR20000016682A - Meander antenna device - Google Patents

Abstract

PURPOSE: An antenna device for a portable cordless communication system is provided to improve antenna bandwidth utilizing a relatively high resistance, enhance mechanical endurance, and supply an antenna suitably installed in a limited volume. CONSTITUTION: The device comprises a first element and a second element which are synchronized to a first frequency and a second frequency and have a first and a second axes of a central length direction, respectively. The elements are meanderingly arranged and agitatedly extended toward a positive and a negative angle directions to the first and the second axes, respectively.

Description

Meander antenna

A common problem when the size of the antenna radiator is reduced is that the bandwidth is reduced accordingly. In general, spirally arranged radiators are used when the antenna is required to be installed in a limited volume with a limited height. However, the loop of the helical antenna produces a magnetic field that combines energy which results in a greater reduction in 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 antenna means having a plurality of windings formed by conductive radiating elements formed on a dielectric substrate. The substrate may be tubular with conductive strips on one side, with the strips abutting along the meeting edge of the tubular substrate. In another embodiment, the substrate is a plate and has conductor strips deposited on both sides, the strips sticking together by feed-through along opposite edges of the substrate. Prior art antenna devices have the inherent disadvantages of helical antennas and are difficult and complex to manufacture because of the need to provide feedthroughs in the substrate or to paste conductors at the edges.

Despite being relatively efficient and compact, various prior art antenna devices include the above-mentioned problems due to the use of helical radiators. Such antenna devices are described, for example, in European Patent Application Nos. 0 635 898 A1 and 0 593 185 A1 and 0 467 822 A2, PCT applications WO94 / 10720 and WO95 / 08199 and US Patent No. 4,868,576.

Conventionally, meander antennas have been used when the antenna device is required to have a short overall length compared to the wavelength at which the associated transmitter / receiver is operated. DE-A1 31 29 045 discloses a direction finder antenna with a meandering structure, for example. Its spinning element has a meandering arrangement and is mounted on a dielectric carrier.

DE-A1 31 29 045 is considered to disclose the prior art antenna device closest to the present invention. The problem to be solved is to reduce the height of the orientation finder antenna, in particular to be concealable and movable. However, only meander antennas with a flat panel arrangement are disclosed. Moreover, the principle is to improve the bandwidth of the antenna by using a conductor with a relatively high resistance, resulting in a lower efficiency antenna. In addition, there is no preparation to obtain an antenna with mechanical durability or an antenna that is suitable for installation in a limited volume or in combination with another type of antenna.

Another planar meandering antenna element is disclosed in the abstract of Japanese Patent Application No. 60 E 1572 (Publication Publication No. 6-90108) and includes a meandering dipole and matching means connected to a coaxial transmission line. A meandering feeder for a helical antenna is disclosed in US Pat. No. 5,298,910. In the latter two devices, the transmission line is not connected to one tip of the meandered conductor.

Pending Swedish patent application no. 9601706-6 includes means integrated with the antenna for matching the antenna to the circuitry of a hand cell phone. Also, in the present invention, similar matching means are suitable. Therefore, the above mentioned Swedish patent application is incorporated herein by reference.

It is an object of the present invention to tune to a first frequency and to have a central longitudinal first axis, the first and second leading ends being the first supply point and the first open end, respectively, and having a radial first element in a meandering arrangement. By providing an effective antenna means for a portable radio communication device configured, it solves the problem of providing an antenna means having a geometric shape that is mechanically durable and suitable to be placed in a small volume. A further object of the present invention is to provide a surrogate in place of a helical radiator that provides improved antenna performance, to overcome the above-mentioned problems of the radiators of the antenna means or the electromagnetic energy coupled to the radiator, and to accommodate the radiating element. To avoid feed-through in the carrier, to provide efficient and cost-effective impedance matching means integrated with the antenna means, to provide an efficient and mechanically durable arrangement, and to use more accurate production techniques such as wound spirals It is possible to provide an antenna in which other radiating elements can be combined, particularly in a coupling including an extensible whip antenna, without mutual coupling in the reverse direction.

The present invention is a radiating agent tuned to a first frequency, having a central longitudinal first axis, having a first supply point and a first open end, respectively, and having a meander configuration, having a first longitudinal end and a second end; The present invention relates to an antenna means for a portable radio communication device having one element, and more particularly, to an antenna means for a hand portable mobile phone requiring a compact and effective antenna. In particular, the antenna means of the present invention is preferable when two or more radiating elements are combined, or an impedance matching means for matching the radiating elements of the antenna means to the transmission / reception circuit of the telephone is required.

1A to 1B illustrate a hand portable mobile phone having an antenna means according to various and basically similar embodiments of the present invention in which a meandering conductor extends and protrudes in a cylindrical shape from a chassis of a telephone having an elongate and retractable whip antenna. Drawing,

2a to 2c show different possible meandering conductor arrangements 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 dual tunes tuned at different frequencies on a common flexible film carrier with dual band operability of the antenna means according to the invention, which are supplied individually or via a common feed point to the double meander conductors; Drawing showing meandering conductors,

4 shows a combination of a cylindrical arrangement and a meandering conductor with an elongate and retractable whip antenna;

5 is a cylindrical arrangement in which the flexible film carrier of the meandering conductor has impedance matching means for matching the impedance of each of the meandering conductor and the whip antenna with an impedance on the transmitter / receiver of the mobile telephone, and an elongate and retractable whip antenna; Drawing showing a combination of meandering conductors,

6 shows another combination of the meandering conductor and the whip antenna in series when the whip antenna is in an extended position and the meandering conductor with the elongated and retractable whip antenna;

7 shows another combination of meandering conductors with coaxial transmission lines connected to meandering conductors and whip antennas, respectively, and for elongate and retractable whip antennas;

8 shows a combination of a meander antenna and an extendable and retractable whip antenna 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-10B illustrate a further combination of meandering antennas, wherein the top of the whip antenna may or may not be conductively connected to the meandering conductor, and an elongate and retractable whip antenna.

This and other objects are achieved by an antenna means in which the first element extends with stirring in the positive and negative angular directions with respect to the first axis. It can be found that the geometry of such radiators has particular advantages in terms of stability, bandwidth and radiation characteristics. Since the radiating 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 radiating element. This arrangement allows the antenna means according to the invention to be used in most applications of wireless communication devices, especially for mobile telephones 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 leading to lower disposal, and a lower degree with certain adjacent radiators which greatly improve multiband operability. And the possibility of integrating an impedance matching network on the same carrier, at least in part, with the same production technology. Radiating elements which agitate and extend in positive and negative angular directions with respect to their central axis preferably have a meandering curve which changes the circumferential direction at least once in extension along the longitudinal axis of the virtual cylindrical sheath having a round or oval base. It can be understood as including a radiating element.

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. In the same sequence of processing steps, it is possible to produce all spinning elements simultaneously.

In particular, when the limitation of the electromagnetic energy coupled in the radiating structure is important, it does not include any complete winding at all, and may preferably only include an arrangement that draws a small portion of the complete winding around the central axis.

The first and second supply points can be interconnected and can 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. Printing technology is suitable for manufacturing mass production.

The advantage of coupling the antenna means according to the invention to an elongate and retractable whip antenna is evaluated from the following preferred embodiment. Here, the carrier and the conductor of the antenna means may comprise one or more switches for connecting or cutting the other radiating element, 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 is incorporated on the carrier, or the structure and the circuit of the wireless communication device are combined. Bars are typically interfaced at 50 ohms.

The meandering radiation element 1 with reference to FIG. 1A is accommodated in the cylindrical carrier 2 of the dielectric and mounted so as to extend outward on the chassis 3 of the handheld mobile telephone 4. The location of the meandering element 1 on the chassis 3 is chosen such that the radiation of the meandering conductor 1 is effectively transmitted / received to another location selected by the exchange during the waiting or during a telephone conversation. 1A-1B, the meandering element is located on one side of the upper part of the chassis 3 and protrudes upwards.

FIG. 1A also shows when the extendable and retractable whip antenna 5 is in its extended position. 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 radial element which is a conductor pattern etched onto a flexible film carrier 7 of a dielectric in a flat panel arrangement. The radiating element is an alternating curve comprising a parallel part and a semicircular winding, from the supply point 8 of one edge of the carrier 7 having a substantially rectangular shape to the free end 9 of the opposite edge of the carrier 7. Is extended. The single meandering spinning element is formed below from a flat plate arrangement in which the carrier 7 forms a tubular or at least cylindrical portion.

Figures 2b and 2c show the second and third alternative forms 10, 11 of the meandering element comprising rectangular and serrated shapes, respectively, with corresponding reference numerals, the form of the meandering element of Fig. 2a. It is formed with the carrier 7 in a similar fashion to 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 is compact and provides high durability. Basically it can 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, and preferably has 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. 2A has an imaginary central axis, with the relative angle of the arcuate meandering element 12 alternately increasing and decreasing with respect to this axis.

In Fig. 3a, dual meander elements 14 and 15 on the common carrier 16 are tuned to two different frequencies allowing the operation of the antenna means in two overlapping or two separate frequency bands. This element is supplied by a common supply point 17, possibly coupled to the circuit of the hand portable mobile phone 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, in spite of being depicted as a well functioning flat plate arrangement, it is preferred that the flexible film carrier of the multi meandering means is formed in a cylindrical arrangement as described above for a single meandering element.

Since the degree of coupling between the individual elements is much smaller in the meander element than in the spiral element exhibiting the same or comparable geometric separation, the meander element has a significant advantage over the spiral element for operation in separate or wider frequency bands. It is shown by the calculations and confirmed by simulation and testing.

3B shows another example of the supply arrangement of FIG. 3A. Here, each individual element 18, 19 has a supply point 20, 21, respectively, which is individually coupled to the telephone circuit, possibly via impedance matching means.

The combination with reference to FIG. 4 is a meandering spinning element 22 arranged in a cylindrical shape in which one point received by the cylindrical flexible film 23 carrier is the supply point 24 and the other point is the free end 25, as shown in FIG. As the whip antenna 26 extends, the whip antenna 26 is provided at the opposite end 29 with a stopper 27 at the bottom applied to contact the feed point 24 of the meandering element via the contact member 28 as a medium. It is shown that it includes an elongate and retractable conductive whip antenna 26 with an elongated dielectric portion 30 of the whip antenna which is terminated by the knob 31 for support as it slides.

Basically, the length of the elongated dielectric portion 30 is equal to the length of the meander element 22 arranged in a cylinder, so that when in the retracted position, the whip antenna 26 does not extend the same length as the meander element 22. (Pointed at Figure 8).

In Fig. 4, the radiators 22 and 26 of the antenna means are preferably both half-wave or quarter-wave type.

In general, whilst higher antenna performance is required, such as during phone calls, the whip antenna is extended to contact the feed point of the meander element via the contact member so that 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 this type with more complicated switching means which completely disconnect from one of the elements when not needed.

In Fig. 5, a general method of arranging the integrated impedance matching means 32 on the dielectric carrier 33 of the antenna device of the present invention is shown schematically. The matching means 32 are connected to the supply point 34 of the meander element 35, and the reaction elements 36, 37 (shown diagrammatically) and the connection terminals 38 for telephone signals and ground connectors (not shown). 39).

Preferably, the device 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. A retractable whip antenna 42 is included. This arrangement is similar to the arrangement of FIG. 4 in that the whip antenna 42 is supplied conductively and capacitively at the bottom 45 of the whip antenna 42 by the top of the meander element 40 when the whip antenna 42 is in its extended position. Even more different.

Preferably, the device of FIG. 7 is basically 1/4 wave with a quarter wave meander element 46 on a cylindrical carrier 47 and a long portion 49 of the dielectric mounted on top 50. And extendable and retractable whip antenna 48. This arrangement is different from the arrangement of FIG. 4, when the whip antenna 48 is in an extended position, the lower end 53 of the whip antenna 46 passing the inner conductor 51 of the (coaxial) transmission line 51. And the upper end 54 of the meander element 46 is supplied by the shield 55 of the transmission line 52 while the lower end 56 of the meander element 46 is an open end. do.

When a more compact antenna means is required, the whip antenna 57 is shrunk as shown in FIG. The whip antenna 57 then provides a low or very small antenna function while the meander element 58 transmits / receives radiated power to the telephone. Here, the dielectric portion 59 extends along the entire axial length of the meander element 58, so that the whip separates in the retracted position.

On the other hand, as shown schematically in FIG. 9, the whip antenna 60 is arranged in a cylindrical shape even though the whip antenna 60 is in a retracted position in order to reduce the storage depth required in the chassis of the handheld mobile phone. Can be extended at least partially with the meandering element 61. In this case, the long dielectric portion 62 only partially extends with 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). Since there is a conductive connection between the whip and the meandering element, they are in contact with the sleeve 66 at the portion 64 when they are retracted and at the portion 67 when they are retracted, or there is no conductive contact so only the meandering element 65 is retracted. The sleeve 66 is in contact with the sleeve 66 and only the antenna whip 63 is in contact with the sleeve 66 in the extended position.

If one or more meander elements are included, various multiband antenna means can be constructed according to the principles described above with reference to FIGS. 4 to 10.

Although the invention has been described in connection with a number of preferred embodiments, it is understood that various modifications may be made without departing from the scope and spirit of the invention as defined by the dependent claims. One such possible variant provides different feed means and feed arrangements than those shown in FIGS. 4 to 10.

Claims (19)

Tuned to the first frequency, An antenna means for a portable wireless communication device having a central longitudinal first axis, the first and second leading ends being a first supply point and a first open end, respectively, and having a radial first element in a meandering arrangement. , And the first element extends with stirring in the positive and negative angular directions with respect to the first axis. The method of claim 1, further tuned to a second frequency different from the first frequency, With a central longitudinal second axis, the first and second ends being the second feed point and the second open end, respectively, in a meandering arrangement, And an emissive second element extending while stirring in positive and negative angular directions with respect to the second axis. Tuned to the first frequency, An antenna means for a portable wireless communication device having a central longitudinal first axis, the first and second leading ends being a first supply point and a first open end, respectively, and having a radial first element in a meandering arrangement. , Tuned to a second frequency different from the first frequency, With a central longitudinal second axis, the first and second ends being the second supply point and the second supply end, respectively, with a second element in a meandering arrangement, And the antenna means are adjustable within the first and second frequency bands around the first and second frequencies, respectively. Antenna means according to any one of the preceding claims, characterized in that the radiating element does not comprise a complete winding around the central axis. The antenna means according to any one of claims 2 to 4, wherein the first and second supply points are interconnected. The antenna means according to any one of the preceding claims, further comprising a dielectric carrier for receiving the radiation element and mounted on the wireless communication device such that the radiation element protrudes outward. The carrier of claim 6, further comprising: a carrier with a carrier surface, And an emissive element formed by a conductive film provided on the carrier surface. 8. The antenna means according to claim 6 or 7, further comprising a carrier which is a flexible dielectric film having a printed conductive film constituting the radiation element on its surface. 9. The antenna means of claim 8, wherein the dielectric film is substantially cylindrical in shape of a wall of cylindrical or part of the cylinder. The antenna means according to claim 1, wherein the element having a meandering arrangement has a shape corresponding to at least a portion of the cylindrical wall. The antenna means according to any one of the preceding claims, further comprising an extendable and retractable whip antenna that can be manipulated in combination with an element having a meandering arrangement. 12. The device of claim 11, wherein an element with a meandering arrangement is secured to the chassis of the radio, through which the extendable and retractable whip antenna is slidable, When the whip antenna is in the retracted position, the element with the meander 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 whip antenna is slidable into and out of the chassis of the radio, An element with a meandering arrangement is fixed coaxially to one end of the whip antenna, positioned outside the chassis for all time, When the whip antenna is in the retracted position, the element with the meander arrangement is coupled to the circuitry of the radio, And the whip antenna is coupled in series with the element with the meander arrangement when the whip antenna is in the extended position. 12. The device of claim 11, wherein the whip antenna is slidable into and out of the chassis of the radio. An element with a meandering arrangement is fixed coaxially to one end of the whip antenna, positioned outside the chassis for all time, When the whip antenna is in the retracted position, the element with the meander 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. 12. The elongated and retractable whip of claim 11, wherein an element with a meandering arrangement, preferably with a quarter wave characteristic, is secured to the chassis of the radio, preferably through which it has a basically half wave characteristic. The antenna is slidable, When the whip antenna is in the retracted position, the element with the meander arrangement is coupled to the circuitry of the radio, Antenna element, characterized in that when the whip antenna is in an extended position, the whip antenna is coupled to the circuit, preferably capacitively, via the upper end of the element. The element of claim 11, wherein the element with the meandering arrangement is secured to the chassis of the radio, through which the extendable and retractable whip antenna is slidable, When the whip antenna is in the retracted position, the element with the meander arrangement is coupled to the circuitry of the radio at the top via a transmission line extending through the element with the meander arrangement, And the antenna means coupled to the circuit via the transmission line at the bottom when the whip antenna is in the extended position. 13. The device of claim 11 or 12, wherein an element with a meandering arrangement is secured to the chassis of the radio, through which a whip antenna extending and contracting is slidable, When the whip antenna is in the retracted position, the element with the meander arrangement is coupled to the circuitry of the radio, And when the whip antenna is in the retracted position, the whip antenna is separated from the circuit and extends at least partially inside the element with a meander arrangement to reduce the depth of extension to the radio. 18. The antenna means according to any one of claims 6 to 17, further comprising a dielectric carrier incorporating an impedance matching means for matching the impedance of the radiating element to a circuit of a wireless communication device. 19. The at least one other radiation element of any one of claims 2 to 18, having a meandering arrangement and similar to the first and second elements but tuned to a third frequency different from the first and second frequencies. Antenna means, characterized in that further provided.