KR20020010025A - Radiotelephone with improved antenna gain - Google Patents

Abstract

PURPOSE: A terminal in which an antenna gain is improved is provided to miniaturize a body of the terminal and improve the antenna gain. CONSTITUTION: A PCB(Printed Circuit Boards)(51) is composed in a body. A plate spring(101) is fixed to the PCB(51). A ground plate is contacted to the plate spring(101), and has an intermediate portion(102a) contacted with portions(31a,306a) to be processed by a spray at a lower surface of an upper casing frame(31). The plate spring(101) has a fixing terminal(101a) and a free terminal. The fixing terminal(101a) is fixed to an end of the PCB(51), and the free terminal is toward a downward direction in the PCB(51) and has an elastic force curved in an external direction.

Description

Terminal with improved antenna gain {RADIOTELEPHONE WITH IMPROVED ANTENNA GAIN}

The present invention relates to a terminal that enables a subscriber to perform wireless communication using a mobile communication network, and more particularly, to a terminal having an improved antenna gain.

In general, the term "terminal" is functionally classified as a terminal primarily intended for voice communication and video communication, and is externally bar type, flip type, folder type, and wrist. It is classified into a wear type and the like. Among these terminals, in accordance with the trend toward miniaturization and light weight of terminals, flip-type or folder-type terminals have become popular, and in the future, wrist-type terminals will be in the spotlight. Conventional flip type terminals have been popularized because flips are mechanically connected to the main body by a hinge device to protect a plurality of keys of the main body, and serve as a reflector of voice during a call. Since it can accommodate, it is advantageous to miniaturization and weight reduction. Conventional folder type terminals have been generalized because folders are mechanically connected to the main body by a hinge device to protect a plurality of keys of the main body, and serve as a reflector of voice during a call. Since it can accommodate etc., it is advantageous for miniaturization and weight reduction. In addition, the terminal includes a whip antenna to improve antenna reception sensitivity. Such a whip antenna has mobility that is pulled in or out of the body. When the user is located in an area where the reception sensitivity of the antenna is degraded, the user pulls the whip antenna out of the main body completely to improve the antenna reception sensitivity during a call, and fully inserts the whip antenna into the main body when the call is terminated. . In other words, in consideration of the mobility of the whip antenna, the length of the main body is designed in consideration of the length of the whip antenna. The length of the body shall be greater than the length of the whip antenna.

The terminal pursues miniaturization in order to maximize convenience in carrying, and such miniaturization means miniaturization of a main body. The "miniaturization of the body" means that the overall size of the product is reduced. In particular, the fact that the overall size of the product becomes smaller means that the length of the main body becomes smaller.

As shown in FIG. 1, the terminal 10 according to the conventional embodiment is not sprayed with a conductive material on the bottom surface 14 of the upper casing frame 12 facing the printed circuit board 11, or As shown in FIG. 2, the terminal 20 according to the conventional embodiment improves antenna gain by spraying 24 of conductive material on the bottom surface of the upper casing frame 22 facing the printed circuit board 21. It was intended to promote.

However, as in the related art, even if the bottom surface of the upper casing frame is sprayed with a conductive material, the technical problem for miniaturization of the main body has not been completely solved. In particular, when the length of the main body is 100 mm or less, the complete antenna gain is achieved. There is a limit to compensation.

For reference, the relationship between the frequency of use of the terminal, the length of the main body, and the antenna performance will be described. First of all, in the case of CDMA terminals, the characteristics of gain reduction along the length of the miniaturization were investigated. For this test result, the width of the main body was tested with a constant width. The reason is that the width of the terminal affects the gain of the antenna is almost negligible. Therefore, it is examined whether the width of the terminal affects the gain of the antenna. Refer to Table 1 for the experimental results.

Table 1

Product wavelength (λ) Product length (mm) PCB length (mm) Gain (㏈i) 0.270 λ 96 mm 92 mm -1.8 ㏈i 0.280 λ 98 mm 93 mm -1.5 ㏈i 0.286 λ 100 mm 96 mm -1.2 ㏈i 0.294 λ 103 mm 99 mm -0.8 ㏈i 0.300 λ 105 mm 101 mm -0.5 ㏈i 0.306 λ 107 mm 103 mm -0.2 ㏈i 0.311 λ 109 mm 105 mm +0.0 ㏈i

On the other hand, when the gain of the antenna was measured using a whip antenna of 8.5 mm in length and 0.9 mm in diameter, it was about +1.8 ㏈i. That is, the gain of the extracted whip antenna became +1.8 ㏈i. For example, a CDMA terminal has a transmission frequency of 824 MHz to a reception frequency of 869 MHz to 894 MHz. The center frequency of the operating frequency of the CDMA terminal is 858 MHz. The calculation of the wavelength (λ) for the product's service frequency of 858 MHz is as follows.

λ = V / f = 3 × 10 ¹⁰ (cm / sec) / 858MHz (sec ⁻¹ ) = 350mm

When the length of the terminal is shortened to 100 mm, the gain of the whip antenna is reduced as shown in the test results in Table 1. At this time, the problem is that the transmission and reception success rate is reduced in the weak field area, there is a problem that the call is not received, dialing is not possible. In addition, when the terminal is in contact with the ear to make a call in the weak field, there is a problem that the call is not able to continue because of the problem of boiling the sign. Thus, when trying to make a call in the weak electric field, if the call is not made well or the telephone signal is boiled during the call, the whip antenna of the terminal is withdrawn from the main body.

Thus, basically, when the mobile phone is miniaturized and the antenna gain falls, there is a problem in that the signal is not received, and there is a problem in that the weak field does not receive a call. Accordingly, the following problems have arisen in pursuit of miniaturization of the main body. In pursuit of miniaturization of the main body, the length of the main body should be shortened. However, if the main body is shortened, the length of the whip antenna should be shortened. If the length of the whip antenna is shortened, there is a problem that the antenna performance of the terminal is degraded. The proper gain of the antenna can be obtained only if the overall length of the terminal is maintained to a certain length, but if the length of the main body is too short, it causes a problem of reducing the gain of the antenna.

Conventionally, the terminal body has a length of about 110 mm to 107 mm, and currently, a product is being developed to 100 mm or 103 mm. In particular, in the case of a CDMA terminal, when the frequency used is 824 MHz to 848 MHz and the reception frequency is 869 MHz to 894 MHz, a problem occurs that the gain of the antenna is lowered. As a result, the length of the product of the terminal for the length of the antenna of a constant length affects the gain of the antenna. Accordingly, the present invention is to compensate for the antenna gain caused by shortening the product length when developing a miniaturized product which is convenient for portability.

SUMMARY OF THE INVENTION The present invention has been made to solve the above technical problem, and an object of the present invention is to provide a terminal simultaneously pursuing two purposes of miniaturization of a terminal body and improvement of an antenna gain.

The present invention to achieve the above object is a main body including a printed circuit board (a); Flip (b); And a hinge device (c) which mechanically connects the main body (a) and the flip (b) to open and close up to a call angle.

The printed circuit board;

A plate spring of a conductive material having a fixed end connected to a predetermined position of the printed circuit board, a free end of which is directed downward from the printed circuit board, and a free end of which is bent in an outward direction to retain elasticity; And

It is connected to the free end of the leaf spring, it is composed of a ground expansion plate that is elastically received in the direction to be close to the free end, and is mounted to extend in the hinge axis direction.

1 is a cross-sectional view showing the internal structure of a terminal according to a conventional embodiment.

2 is a cross-sectional view showing the internal structure of a terminal according to another embodiment of the prior art.

3 is a perspective view illustrating a terminal in which a flip is closed;

4 is a perspective view showing a terminal with a flip open;

5 is a perspective view showing a means for improving the antenna gain according to the present invention;

Figure 6 is a perspective view of the ground expansion plate according to the present invention.

7 is a cross-sectional view showing a state in which a means for improving antenna gain according to a first embodiment of the present invention is applied to a terminal;

8 is a cross-sectional view showing a state in which a means for improving antenna gain is applied to a terminal according to a second embodiment of the present invention;

9 is a sectional view showing a state in which a means for improving antenna gain is applied to a terminal according to a third embodiment of the present invention;

10 is a perspective view illustrating a state in which a means for improving antenna gain according to a fourth embodiment of the present invention is applied to a flip;

11 is a perspective view illustrating a state in which a means for improving antenna gain according to a fifth embodiment of the present invention is applied to a flip;

12 is a graph showing the maximum antenna gain when the main body is 109 mm in length and has a use frequency of 858 MHz.

Fig. 13 is a graph showing the maximum antenna gain when the main body is 100 mm in length and has a use frequency of 858 MHz.

Fig. 14 is a graph showing the maximum antenna gain when a ground extension plate is mounted when the main body is 100 mm in length and the use frequency is 858 MHz.

Fig. 15 is a graph showing the maximum antenna gain when a conductive tape is attached to the flip with the flip open in the main body when the main body is 100 mm in length and the use frequency is 858 MHz.

Fig. 16 is a graph showing the maximum antenna gain when a conductive tape is attached to the flip with the flip closed in the main body when the main body is 100 mm in length and the use frequency is 858 MHz.

Hereinafter, with reference to the accompanying drawings will be described a preferred embodiment of the present invention; In describing the present invention, detailed descriptions of related well-known functions or configurations are omitted in order not to obscure the subject matter of the present invention.

It should be noted that the terminal whose antenna gain is compensated according to the present invention is not limited to the flip type terminal, but can be equally applied to the folder type terminal and all other terminals. The present invention will be described taking an example applied to the flip type terminal. 3 is a perspective view showing a typical terminal in which the flip 40 is closed in the main body 30. 4 is a perspective view illustrating a conventional terminal in a state in which the flip 40 is opened in the main body 30. 3 and 4, a conventional flip type terminal is a hinge device for mechanically connecting the main body 30, the flip 40, the main body 30 and the flip 40 to open and close to a call angle (Fig. Not shown). The flip 40 is opened and closed about the hinge axis A in the main body 30. The main body 30 is a microphone device provided in the antenna housing 301, the ear piece 302, the LCD 303, the plurality of keys 304, and the hinge receiving portion 306, in which the whip antenna 301a is accommodated. 305). In addition, the main body 40 is composed of an upper casing frame 31 and a lower casing frame 32.

3 illustrates a state in which a call is not made, that is, a terminal in a call standby mode, in which a whip antenna 301a is retracted from the main body 30. 4 illustrates a state in which the flip 40 is opened to make a call and the whip antenna 301a is pulled out of the main body 30 to improve antenna reception sensitivity. That is, the whip antenna 301a is drawn in the direction of the arrow from the main body 30 in order to increase the reception sensitivity of the antenna according to the call area. At this time, the length of the main body 30 is designed to be longer than the length of the whip antenna 301a in consideration of the mobility of the whip antenna 301a in the longitudinal direction.

5 is a perspective view showing a means for improving the antenna gain according to the present invention. Referring to FIG. 5, the means for improving the antenna gain includes a printed circuit board 51 provided in a main body, a plate spring 52 fixed to the printed circuit board 51, and a connection to the plate spring 52. Ground extension plate 53. The leaf spring 52 has a fixed end 52a and a free end 52b, the fixed end 52a is fixed to the end of the printed circuit board 51, and the free end 52b is a printed circuit. It is directed downward from the substrate 51 and is bent outward to take the shape of retaining elasticity. In addition, the ground extension plate 53 has a cross-sectional shape of "c" type.

6 is a perspective view showing the ground expansion plate 53 according to the present invention. The ground extension plate 53 has a length in the hinge axis direction of 30 mm, a vertical height of 6.0 mm to 7.0 mm, and a width of the middle portion of 0.4 mm to 0.6 mm. When the said ground extension plate 53 is spread out in flat form, it is 12 mm-14 mm. Here, the length of the ground extension plate in the hinge axis direction is limited to 30 mm, but this length may be reduced, and a slight length change is possible depending on the mechanism structure, and it is also possible to maintain such a shape. What is important is that the sum of the overall lengths when the ground extension plate 53 is unfolded in a flat shape is important. It is important that the antenna gain is improved by 12 mm to 14 mm, at least when the ground extension plate 53 is extended.

Preferably, in the present invention, the ground extension plate 53 is applied to one printed circuit board as an example, but need not be limited to one, and two or three or more ground extension plates may be applied. As a result of using two ground extension plates 53 according to the present invention, when the length is about 1 mm, the antenna gain can be improved by about +1.4 μi. Therefore, the present invention compensates for the reduced gain in the state of reducing the length of the terminal body by about 10 mm.

7 is a cross-sectional view illustrating a state in which a means for improving antenna gain is applied to a terminal according to the first embodiment of the present invention. Referring to FIG. 7, the means for improving the antenna gain includes a printed circuit board 51 provided in the main body, a plate spring 101 fixed to the printed circuit board 51, and a plate spring 101 connected thereto. In addition, the bottom surface of the upper casing frame 31 is composed of a ground extension plate 102 having an intermediate portion 102a in contact with the portions 31a and 306a sprayed with a conductive material. The leaf spring 101 has a fixed end 101a and a free end 101b, the fixed end 101a is fixed to the end of the printed circuit board 51, and the free end 101b is a printed circuit. It is directed downward from the substrate 51 and is bent outward to take the shape of retaining elasticity. In addition, the ground extension plate 102 has a cross-sectional shape of the "c" type.

8 is a cross-sectional view illustrating a state in which a means for improving antenna gain is applied to a terminal according to a second embodiment of the present invention. Referring to FIG. 8, the means for improving the antenna gain includes a printed circuit board 51 provided in the main body, a conductive plate spring 201 fixed to the printed circuit board 51, and a connection to the plate spring 201. In addition, the bottom surface 306 of the upper casing frame 31 is composed of a portion 306a sprayed with a conductive material. The conductive plate spring 201 has a fixed end 201a and a free end 201b, the fixed end 201a is fixed to the end of the printed circuit board 51, and the free end 201b is printed. It is directed upward from the circuit board 51 and is bent outward to take a shape having elasticity. The free end 201b is configured to be in contact with the sprayed portion 306.

9 is a cross-sectional view showing a state in which a means for improving antenna gain according to a third embodiment of the present invention is applied to a terminal. 9, the means for improving the antenna gain includes a printed circuit board 51 provided in a main body, a conductive plate spring 311 provided at a predetermined position of the printed circuit board 51, and the leaf spring. And a first ground extension plate 312 in contact with 311 and second ground extension plates 313 and 314 attached to the bottom surface of the main casing frame 31. The leaf spring 311 has a fixed end 311a and a free end 311b. The fixed end 311a is fixed to one end of the printed circuit board 51, and the free end 311b is in contact with one end of the first ground extension plate 312. The second ground extension plates 313 and 314 are mounted in a manner of being attached or fixed to the bottom of the upper casing frame 31 and are installed to the bottom of the lower 306 of the upper casing frame.

10 is a perspective view illustrating a flip 40 to which a means for improving antenna gain according to a fourth embodiment of the present invention is applied. Referring to FIG. 11, a tape 401 made of a conductive material is attached to the bottom surface 40a of the flip 40. The conductive material is copper or aluminum. When the flip 40 is closed in the main body, the improvement of the antenna gain is almost negligible. However, when the flip 40 is opened in the main body, the antenna gain is improved. The applied tape is preferably applied to a size that almost covers the bottom of the flip. In particular, the length of the conductive tape 401 according to the present invention is about 20mm to 30mm, it is possible to closely adhere to the main body. The reason is that when opening the flip 40 in the body, a lot of capacitive coupling occurs between the conductive tape of the flip and the ground of the body. Here, in consideration of mass productivity, the conductive material is preferably applied in a manner of being attached. In particular, even when the flip 40 is bent, when applied in a manner of attaching like a tape, there is no abnormality in antenna characteristics.

11 is a perspective view illustrating a flip to which a means for improving antenna gain according to a fifth embodiment of the present invention is applied. Referring to FIG. 11, a looped tape 501 is attached to the bottom surface 40a of the flip 40. The loop tape 501 is a conductive material and is made of copper or aluminum. The applied looped tape 501 is attached along the edge of the flip bottom. As a result of using the loop-shaped conductive tape 501, the gain of the antenna in the flipped open state was improved by +1.0 ㏈i. As a result, there is an improvement effect in removing the call drop and the mute of the handset when the user opens the flip in the weak field.

On the other hand, as a structure for applying a conductive material to the flip, a method of plating the edge with chrome or the like instead of the conductive tape can also be applied. Plating the edge of the flip with chrome or the like does not limit the flip's design.

Referring to Table 2, the experimental results to which the means for improving the antenna gain according to the present invention are applied are as follows. When the ground extension plate is applied to the terminal, it can be seen that the antenna gain is improved as compared with the related art. In addition, when the conductive tape is applied to the flip, it can be seen that the antenna gain is improved as compared with the conventional one, especially when the flip is opened, the antenna gain is improved. In addition, when the ground extension plate and the conductive tape are applied together, the antenna gain is improved as compared with the conventional art. In particular, when the flip is opened, the antenna gain is further improved to compensate for the lost antenna gain generated when the main body is downsized.

Table 2

Wavelength (λ) Product length (mm) PCB length (mm) Prior art (A): No application Using GND Extensions (B) Apply conductive tape to flip (C) D (B + C) a (gain) b = a + 1.4㏈i c = a + 1.0㏈i (improved only when opening the flip) d = a + 1.8㏈i (when the flip is open) d = a + 1.4㏈i (when the flip is closed) 0.270 λ 96 mm 92 mm -1.8 ㏈i NOT TEST NOT TEST NOT TEST 0.280 λ 98 mm 93 mm -1.5 ㏈i NOT TEST NOT TEST NOT TEST 0.286 λ 100 mm 96 mm -1.2 ㏈i + 0.2㏈i c = -0.2㏈i (when the flip is open) c = -1.2㏈i (when the flip is closed) d = + 0.6㏈i (when the flip is opened) d = + 0.2㏈i (when the flip is closed) 0.294 λ 103 mm 99 mm -0.8 ㏈i NOT TEST NOT TEST NOT TEST 0.300 λ 105 mm 101 mm -0.5 ㏈i NOT TEST NOT TEST NOT TEST 0.306 λ 107 mm 103 mm -0.2 ㏈i NOT TEST NOT TEST NOT TEST 0.311 λ 109 mm 105 mm +0.0 ㏈i NOT TEST NOT TEST NOT TEST

12 is a graph showing the maximum antenna gain when the main body is 109 mm long and has a use frequency of 858 MHz. 13 is a graph showing the maximum antenna gain when the main body is 100 mm in length and has a use frequency of 858 MHz. Fig. 14 is a graph showing the maximum antenna gain when the ground extension plate is mounted when the main body is 100 mm in length and the use frequency is 858 MHz. Fig. 15 is a graph showing the maximum antenna gain when a conductive tape is attached to the flip with the flip open in the main body when the main body is 100 mm in length and the use frequency is 858 MHz. Fig. 16 is a graph showing the maximum antenna gain when a conductive tape is attached to the flip with the flip closed at the main body when the main body is 100 mm in length and the use frequency is 858 MHz. 12 to 16, it can be seen that the antenna gain is improved by applying the ground extension plate and the conductive tape according to the present invention. In particular, the antenna gain is improved when the flip is open.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but it will be apparent to those skilled in the art that various modifications can be made without departing from the scope of the present invention.

As described above, the present invention can compensate for the lost gain even if the actual body length is shortened to about 10 cm if only about 1 mm of space exists inside the main body. Accordingly, the present invention simultaneously achieves miniaturization of the main body and improvement of antenna gain.

Claims (8)

A main body (a) including a printed circuit board; Flip (b); And a hinge device (c) which mechanically connects the main body (a) and the flip (b) to open and close up to a call angle. The printed circuit board; A plate spring of a conductive material having a fixed end connected to a predetermined position of the printed circuit board, a free end of which is directed downward from the printed circuit board, and a free end of which is bent in an outward direction to retain elasticity; And And a ground extension plate connected to a free end of the leaf spring and receiving elasticity in a direction toward the free end and extending in the hinge axis direction. The antenna gain-enhanced terminal according to claim 1, wherein the cross-sectional shape of the ground extension plate is "c" type. The terminal of claim 1 or 2, wherein when the ground extension plate is extended in a flat plate shape, the length of the ground extension plate is between 12 mm and 14 mm. A main body including a printed circuit board and a casing frame spray-treated with a conductive material on a bottom surface thereof; Flip (b); And a hinge device (c) which mechanically connects the main body (a) and the flip (b) to open and close a call angle. The printed circuit board; A fixed spring connected to a predetermined position of the printed circuit board, a free end facing downward from the printed circuit board, and a free spring bent outward to retain elasticity; And A ground extension plate connected to the free end of the leaf spring, receiving an elasticity in a direction toward the free end, and having an intermediate portion connected to the bottom surface of the casing frame sprayed with the conductive material and extending in the hinge axis direction; Terminal with improved antenna gain, characterized in that consisting of. A main body (a) including a printed circuit board and upper and lower casing frames; Flip (b); And a hinge device (c) which mechanically connects the main body (a) and the flip (b) to open and close a call angle. The printed circuit board; A part spray-treated with a conductive material on a lower bottom surface of the upper casing frame; A fixed end is connected to a predetermined position of the printed circuit board, a free end is directed upward from the printed circuit board, and the free end is bent outward to retain elasticity and is always connected to the sprayed portion. Terminal with improved antenna gain, characterized in consisting of a leaf spring of the material. A main body including a printed circuit board and a casing frame spray-treated with a conductive material on a bottom surface thereof; Flip (b); And a hinge device (c) which mechanically connects the main body (a) and the flip (b) to open and close a call angle. The printed circuit board; A first ground extension plate installed on the bottom of the main body; A fixed spring connected to a predetermined position of the printed circuit board, a free end facing downward from the printed circuit board, and a free spring bent outward to retain elasticity; And And a second ground extension plate connected to a free end of the leaf spring, receiving a resilience in a direction toward the free end and extending in a hinge axis direction. A main body (a) including a printed circuit board; Flip (b); And a hinge device (c) which mechanically connects the main body (a) and the flip (b) to open and close up to a call angle. The printed circuit board; A plate spring of a conductive material having a fixed end connected to a predetermined position of the printed circuit board, a free end of which is directed downward from the printed circuit board, and the free end of which is bent outwardly to retain elasticity; A ground extension plate connected to the free end of the leaf spring, receiving a resilience in a direction toward the free end and extending in a hinge axis direction; And Terminal with improved antenna gain, characterized in that consisting of a flat tape of a conductive material provided on the bottom of the flip. A main body including a printed circuit board and a casing frame spray-treated with a conductive material on a bottom surface thereof; Flip (b); And a hinge device (c) which mechanically connects the main body (a) and the flip (b) to open and close up to a call angle. The printed circuit board; A fixed spring connected to a predetermined position of the printed circuit board, a free end facing downward from the printed circuit board, and a free end bent outward to retain elasticity; A ground extension plate connected to the free end of the leaf spring, receiving an elasticity in a direction toward the free end, and having an intermediate portion connected to the bottom surface of the casing frame sprayed with the conductive material and extending in the hinge axis direction; ; And The antenna gain-enhanced terminal, characterized in that consisting of a loop-shaped tape of a conductive material provided along the bottom edge of the flip.