JP3662978B2 - Method and apparatus for multi-position antenna - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an antenna for a communication device.
[0002]
[Prior art]
The wireless communication device includes a transmitter and / or receiver coupled to an antenna that emits and / or detects radio frequency signals. The apparatus can include a microphone for inputting an audio signal to a transmitter or a speaker for outputting a signal received by a receiver. Examples of such wireless communication devices include one-way radios, two-way radios, radio telephones, personal communication devices, and various other devices. These communication devices typically have a standby configuration in which the device is folded for storage and an active communication configuration in which the antenna is extended for optimal performance.
[0003]
For radiotelephones and two-way radios, it is generally desirable that these devices have small dimensions during standby mode to facilitate their storage and transport. For example, users prefer to be small enough to allow a wireless phone to be stored in a shirt or jacket pocket while in standby mode. In the active communication state, the device is preferably long enough to place the speaker adjacent to the user's ear, the microphone near the user's mouth, and the antenna away from the user's body. To meet these requirements, the radiotelephone housings are made reconfigurable to have smaller dimensions in standby mode than they have when in active communication mode.
[0004]
[Problems to be solved by the invention]
The difficulty with prior art reconfigurable communication devices, such as radiotelephones that must receive call alert signals in standby mode, is to provide a high performance antenna system in both standby and active communication modes. is there. While the stretched antenna position can provide optimal antenna performance, the shrunken position of the antenna in standby mode that minimizes the size of the communication device results in degradation of antenna performance.
[0005]
An example of a wireless communication device that includes a multi-position antenna is a radiotelephone that includes a body and a flap, where the flap includes an antenna mounted therein. When closed, the flap covers the keypad of the radiotelephone and provides a microminiature housing. When the flap is opened, the flap antenna is away from the phone body held by the user. Although the flap antenna works very well when the flap is open, the flap antenna is not in an ideal position to receive an alarm signal in standby mode.
[0006]
Accordingly, it is desirable to provide an antenna system having high performance characteristics when the communication device is extended in the active communication mode and when the communication device is folded in the standby operation mode.
[0007]
[Means for Solving the Problems]
The present invention is implemented in a multi-position antenna system for an apparatus including a housing having first and second housing portions that move between a first extended position and a second folded position. . Circuitry is disposed within the housing for transmitting or receiving signals. The first antenna is supported by the first housing part and connected to the circuit. A parasitic radiator is supported on the second housing part. The first antenna and the parasitic radiator are coupled when the housing is in the collapsed position and are not coupled when the housing is in the extended position. The antenna system has high performance characteristics when the housing is extended during operational communication and when the first antenna and the parasitic radiator are combined while the housing is folded.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
First, it should be noted that elements shown in more than one drawing have the same last two digits in all drawings. However, the first digit indicates the referenced drawing, for example, the element of FIG. 1 has a first digit of 1, the element of FIG. 2 has a first digit of 2, and so on. It should also be noted that the antenna system according to the present invention is illustrated by a radiotelephone including a flap 103 (FIG. 1) that is particularly advantageous for the present invention. However, the present invention can also be suitably used in other devices, such as one-way and two-way radios, or any other communication device that uses an antenna. Accordingly, “apparatus” and “equipment” as used herein refer to all such apparatuses and their equivalents.
[0009]
A radiotelephone 100 incorporating the present invention is shown in FIG. The radiotelephone includes a housing 102 that includes a first housing portion 101 and a second housing portion 103. In the illustrated embodiment, the first housing part 101 is a radiotelephone body and the second housing part is a flap pivotally attached to the body. The flap 103 moves between the extended position shown in FIG. 1 during the active communication mode and the folded or closed position shown in FIG. 2 in the standby mode.
[0010]
The radiotelephone body 101 includes a back body housing section 104 and a front body housing section 105 that are interconnected to define an internal volume that houses an electronic circuit (not shown). Keypad 106 is positioned on body 101 such that keys 109 associated with the keypad (only some of them are numbered) are accessible for manual activation by the user. The illustrated flap 103 at least partially covers the keypad 106 when closed. The flap may be larger to cover all keys. The flap prevents operation of the covered key 109 when the flap is closed. Further, the phone can place the phone in standby mode when the flap is closed.
[0011]
The flap 103 includes a first antenna 107, referred to herein as a flap antenna. The flap antenna is disposed between the front flap housing section 111 and the back flap housing section 112 and is therefore shown in dotted lines in FIG. The front and back flap housing sections 111 and 112 are substantially flat members that can be made of a suitable polymer. The flap antenna is sandwiched between these members. The flap antenna 107 is in an extended position when the flap 103 is open. The flap antenna is in a folded or deflated position when flap 203 (FIG. 2) is closed.
[0012]
The main body 101 includes a parasitic radiator or a second antenna 108. The parasitic radiator 108 is fixed inside the front housing section 105 and is therefore shown in dotted lines in FIG.
[0013]
The transceiver circuit 315 is shown schematically in FIG. The transceiver can be implemented using any suitable traditional transceiver. The transceiver circuit 315 is disposed in the first housing portion 301 by traditional means, such as mounting on a printed circuit board that is assembled between the front and back body housing sections 104,105. The transceiver circuit 315 is coupled to a microphone (not shown) and a receiver (not shown) disposed within the housing portion 301. The transceiver circuit is also connected to an elastomeric connector 316 or other means that connects to the flex conductor 317. The flex conductor 317 extends to a hinge assembly 318 that includes a knuckle 319. As shown in FIG. 4, the hinge assembly 418 also includes a knuckle 420 on the flap 403 for engaging the knuckle 319. The flex conductor 417 is also connected to the first antenna 407 via the hinge assembly 418. The hinge assembly that provides the connection between the flap antenna 407 and the transceiver 315 can be any suitable structure, such as a US patent application serial number filed Nov. 8, 1993 by Tanya Rush et al. No. 08 / 148,718, the disclosure of which is hereby incorporated by reference.
[0014]
The flap antenna 407 (FIG. 4) includes two conductors 423 and 424 mounted on a substrate 425 so that the antenna has a generally E-shaped configuration. The flap antenna is made by two narrow strips of a suitable conductor, such as copper. The flap antenna 407 includes a joiner segment 422 that electrically couples the intermediate finger segment 426 of conductors 423 and 424 to the flex conductor 417. The intermediate finger segment 426 includes a transmission line transformer 427 that provides impedance matching between the antenna 407 and the transceiver circuit 315 (FIG. 3). A cross member 428 of the conductor 423 connects the intermediate finger segment 426 to the outer finger 429. The outer finger 429 extends substantially orthogonally from one end of the cross member 428. Conductor 424 also includes an intermediate finger segment 426 coupled to cross member 430. The cross member 430 connects the intermediate finger segment of the conductor 424 to the outer finger 431, and the outer finger 431 extends substantially perpendicular to the cross member 430. Elements 432 (only some of which are numbered) extend approximately orthogonally from outer fingers 429 and 431 and allow for the shortening of antenna 407 to allow the antenna to be mounted on the flap. Provide load. Openings 433 cut from each outer finger 429, 431 are provided to receive respective magnets (not shown). The magnet activates a reed switch (not shown) in the radiotelephone housing 101. The reed switch and magnet are not described in detail here, because they do not form part of the present invention.
[0015]
The flap antenna 407 is thus a thin dipole antenna, whereby the antenna is sandwiched between the front housing section 111 and the back housing section 112 to form a thin flap. The antenna is a half-wave antenna having high performance characteristics when the flap is opened, as shown in FIG. The cross members 428 and 430 of conductors 423 and 424 are the high current sections of the flap antenna.
[0016]
A parasitic radiator 508 is shown in FIG. The parasitic radiator is not directly connected to the feed line 317 (FIG. 3) or 417 (FIG. 4) of the flap antenna 407. Parasitic radiator 508 (FIG. 5) is generally U-shaped and includes arms 534 and 536 that extend generally perpendicular to shoulder 535. The elbow 537 extends at an angle of approximately 45 degrees with respect to the arm 534 and the shoulder 535 and joins these members. The elbow 538 extends at an angle of approximately 45 degrees with respect to the arm 536 and the shoulder 535 and joins these members. The parasitic radiator is made from any suitable electrical conductor, such as a thin, flexible copper strip with adhesive on one side.
[0017]
The parasitic radiator is dimensioned according to the signal frequency of the transceiver. More specifically, the longitudinal axis of arm 534 has a length A, the longitudinal axis of elbow 537 has a length B, and the longitudinal axis of shoulder 535 has a length. C, the longitudinal axis of the elbow 538 has a length D, and the longitudinal axis of the arm 536 has a length E. The lengths A, B, C, D and E are such that their sum is approximately equal to one-half of the wavelength of the transceiver signal frequency.
[0018]
A parasitic radiator 608 (FIG. 6) according to the preferred embodiment is coupled to the inner surface 640 of the front housing section 605. The front housing section includes a flat front portion 642 and side walls 643. The opposite side wall 144, not shown in FIG. 6 but visible in FIG. 1, extends parallel to the side wall 643. A parasitic radiator 608 is assembled to the inner surface 640 of the front housing section 605 using a suitable adhesive. The parasitic radiator is flexible so that it conforms to the face 640 when attached to the face 640 of the front housing section. More specifically, the shoulder 635 of the parasitic radiator 608 is attached to the inner surface 640 between the two rows of openings 660 through which the key 109 (FIG. 1) of the keypad 106 protrudes. The shoulder of the parasitic radiator 608 is narrow, so it fits comfortably between the rows of openings without extending into these openings to avoid interfering with the operation of the key 109. The elbow 637 is attached to the surface 640 such that it curves from the front wall 642 to the side wall 643. Arm 634 is attached to wall 643 using an adhesive so that it extends along this side wall. Most preferably, the wall 643 is flat so that the arms 634 extend in a single plane. Arm 536 and elbow 538 are similarly coupled to side wall 144. In this way, thin flexible strips are attached to the inside of the front housing section, and the predetermined positions of the cross members 428, 430 are such that they are between the two rows of openings 660 and the flaps 403 are present. It is mounted so that it sits above the face of the front wall 642 to which the parasitic radiator shoulder 535 is coupled when closed. Accordingly, when the flap is closed, the cross members 428 and 430 and the shoulder portion 535 are aligned and arranged close to each other as represented by the arrows in FIG. The cross members 428 and 430 and the shoulder 535 are separated by the thickness of the front housing section of the flap 103 and the front housing section of the body 101. Furthermore, the shoulder portion 535 of the parasitic radiator is inductively coupled to cross members 428 and 430, which are high current portions of the flap antenna. Since shoulder 535 is coupled to cross members 430 and 428 when the flap is closed, arms 534 and 536 form a second dipole antenna that is parasitically coupled to dipole antenna 407. This bond is an inductive bond.
[0019]
In operation, when the flap is opened, the flap antenna 107 (FIG. 1) is positioned away from the parasitic radiator 108 and the body 101 so that the antenna is in the user, circuit in the body housing 101, or body housing It has high performance characteristics without interference from 101. In this position, the high current section (cross members 428, 430) of the flap antenna 107 is remote from the shoulder 635 of the parasitic radiator 108 so that the parasitic radiator is not coupled to the antenna 107 and the transceiver circuit 315. Will not be joined. As shown in FIG. 2, when the flap is closed, the flap antenna moves to a position approaching the body and circuitry within the housing 101. This degrades the performance of the antenna 107 because the body 102 is in the near field region or volume of the flap antenna. However, the high current sections 428, 430 of the flap antenna 407 are located close to the shoulder 635, thereby causing the two antennas to be parasitically coupled. The performance characteristics of the antenna system are therefore affected by both the parasitic radiator 108 and the flap antenna 107 while the flap is closed. The parasitic radiator is tuned to the communication signal wavelength of the transceiver circuit 315 when the body is in the near field region or volume, while the flap antenna 107 is tuned to the communication wavelength of the transceiver circuit 315 when the flap is open. . Thus, one of the antennas is tuned to the transceiver signal frequency when the flap is open, and the other is tuned to the transceiver circuit when the flap is closed. This coupling of antenna 107 and parasitic radiator 108 greatly improves the characteristics of the antenna system when the flap is closed, thereby eliminating the significant degradation in antenna performance caused by folding the radiotelephone for storage. As a result, the flap antenna does not degrade the ability of the radiotelephone to receive incoming call alert signals, paging signals or e-mail signals.
[0020]
According to another embodiment of parasitic radiator 708, as shown in FIG. 7, arm 734 and arm 736 are coupled to base 735, with elbow 738 and elbow 737 having a curved outer edge, respectively, 90 degrees. Is the corner. The sum of the length F of the arm 734, the length G of the base 735, and the length H of the arm 736 is approximately one half of the wavelength of the transceiver operating frequency. The embodiment of FIG. 5 is more preferred, but it is preferable that the arms 534, 536 if the total length of the antennas are equal (ie, if both antenna embodiments are quarter wavelength antennas). This is because the tips 555 and 556 are farther from the shoulder 535 than the tips 755 and 756 of the arms 734 and 736.
[0021]
Yet another embodiment of the parasitic radiator 808 is shown in FIG. Parasitic radiator 808 includes notches 858 in arms 834 and 836. The arm notch 858 is provided for positioning the arm around a protrusion (not shown) extending outside the front housing section 605. This is particularly desirable when the inner surface of the front housing section has a number of protrusions. The arms 834 and 836 preferably extend in a single plane for optimal antenna performance. This is particularly important because placing the parasitic radiator 508 adjacent to circuitry in the housing 101 adversely affects the performance of the antenna system. However, the disadvantage of the embodiment of FIG. 8 is that the distance from the tips 855, 856 to the shoulder 835 is further reduced by the addition of the notches.
[0022]
【The invention's effect】
Thus, it can be seen that an improved antenna system for a communication device having a movable body section has been disclosed in accordance with the present invention. This antenna system provides high performance characteristics both when the antenna is opened and when the device is folded to facilitate storage.
[Brief description of the drawings]
FIG. 1 is a front perspective view of a wireless telephone in an extended state including an antenna system according to the present invention.
2 is a front perspective view showing a state in which the wireless telephone of FIG. 1 in a standby mode is folded. FIG.
3 is a partial illustration showing the inside of the radiotelephone housing according to FIG. 1 including a transceiver. FIG.
4 is a plan view of the radiotelephone flap of FIG. 1 with the front housing section removed and showing the first antenna. FIG.
5 is a fragmentary perspective view of a portion of the inside of the front housing section of the radiotelephone body according to FIG. 1 showing a portion of a parasitic radiator.
6 is a top view showing a parasitic radiator according to FIG. 5;
7 is a top view showing another embodiment of the parasitic radiator according to FIG. 6; FIG.
8 is a top view showing still another embodiment of the parasitic radiator antenna according to FIG. 6. FIG.
[Explanation of symbols]
100 radio telephone 101 first housing part 102 housing 103 second housing part 104 rear body housing section 105 front body housing section 106 keypad 107 first antenna 108 parasitic radiator 109 key 111 front flap housing section 112 rear flap housing Section 200 Radio telephone 203 Flap 301 First housing part 315 Transceiver circuit 316 Elastomer connector 317 Flex conductor 318 Hinge assembly 319 Knuckle 403 Flap 407 First antenna 417 Flex conductor 418 Hinge assembly 423, 424 Conductor 425 Substrate 426 Intermediate finger Segment 427 Transmission line transformer 428,430 Cross member 429,431 Outer flange Nga 508 parasitic radiator 534 arm 535 shoulder portion 537 and 538 elbow 555, 556 tip

Claims (10)

A housing having a first housing part (102, 103) and a second housing part (102, 103) movably interconnected to move between a folded position and an extended position with respect to each other (101) and a multi-position antenna device for a device (100) comprising a communication circuit (315) disposed in the housing and transmitting or receiving a signal via an antenna system,
A first antenna (107) supported in the first housing portion, the first antenna including a feed line (317, 417) and coupled to the communication circuit in a folded position; and The first antenna (107) is tuned to the communication circuit, and is supported in the second housing part and is tuned to the wavelength of the communication circuit, but directly supplied by the first antenna. A parasitic radiator (108) not coupled to the electrical wire, wherein the parasitic radiator is coupled to the first antenna when the housing is in the folded position and the parasitic radiator is extended from the housing; Is not coupled to the first antenna when in position, thereby allowing the parasitic radiator to pass through the first antenna when the housing is in a folded position. Coupled to a communication circuit in the first housing section;
A multi-position antenna apparatus comprising:   The apparatus includes a hinge assembly (318, 418) that pivotally interconnects the first and second housing portions, and the first antenna is coupled to the communication circuit via the hinge assembly. The multi-position antenna apparatus according to claim 1. The multi-position antenna apparatus according to claim 1, wherein the first antenna includes two conductors (423, 424) disposed in the first housing portion .   The multi-position antenna apparatus according to claim 1, wherein the first antenna is a half-wave antenna.   The multi-position antenna apparatus according to claim 1, wherein the parasitic radiator has a half wavelength.   The multi-position antenna apparatus according to claim 1, wherein the first antenna is a dipole antenna.   The multi-position antenna apparatus according to claim 1, wherein the first antenna is connected to the communication circuit in an extended position and a folded position. A housing having a first housing part (102, 103) and a second housing part (102, 103) movably interconnected to move relative to each other between a collapsed position and an extended position (101) and multi-position for a device (100) comprising a circuit (315) disposed in one of said first or second housing parts for transmitting or receiving signals via an antenna system An antenna device,
A first antenna (107) supported in the second housing part, wherein the first antenna is coupled to the communication circuit in an extended position and in a folded position; Includes two conductors (423, 424), and each of the two conductors is mounted on the second housing portion and includes a cross member (428, 430) connecting the intermediate finger segment to the outer finger; And a parasitic radiator (108) supported in the first housing portion, the parasitic radiator being coupled to the first antenna when the housing is in a folded position and the parasitic radiator is Not coupled to the first antenna when the housing is in the extended position;
A multi-position antenna apparatus comprising:   The multi-position antenna apparatus according to claim 8, wherein the parasitic radiator is substantially U-shaped and includes two arms (555, 556) protruding from a shoulder portion (535).   The cross member (428, 430) and the shoulder portion (535) are located close to each other when the first and second housing portions are in the folded position, thereby the first antenna and the parasitic member. The multi-position antenna apparatus according to claim 9, wherein a radiator is coupled.

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