WO2006100913A1

WO2006100913A1 - Portable device with built-in fm transmitter

Info

Publication number: WO2006100913A1
Application number: PCT/JP2006/304465
Authority: WO
Inventors: Hiroshi Miyagi; Takeshi Ikeda; Akira Okamoto
Original assignee: Niigata Seimitsu Co., Ltd.
Priority date: 2005-03-18
Filing date: 2006-03-08
Publication date: 2006-09-28
Also published as: TW200642419A

Abstract

A portable device with a built-in FM transmitter, in which an antenna is less likely to be damaged and an antenna receiving space is easily obtained. A portable music playback device has an audio playback device for generating an audio signal to be transmitted, a stereo modulation circuit and an FM modulation circuit that FM-modulate the audio signal to generate a carrier wave signal that can be received by an FM receiver, and a transmission circuit for transmitting the carrier wave signal through a transmission antenna (40). An audio signal generation circuit, the modulation circuits, and the transmission circuit are formed on a printed board (200). A loop-like conductor (40A) is formed along the inner peripheral surface of a housing (300) for receiving the printed board (200) and is used as a transmission antenna (40).

Description

Specification

Mobile device with built-in FM transmitter

Technical field

TECHNICAL FIELD [0001] The present invention relates to a portable device having an FM transmitter including an FM transmitter that transmits an FM-modulated signal.

Background art

[0002] Conventionally, portable devices such as cellular phones with built-in FM transmitters are known (for example, see Patent Document 1). O Occurred in a portable device by using a built-in FM transmitter. Audio can be output from an external FM receiver. This makes it possible to output sound generated by a portable device that does not have the power from an external speaker, or to improve sound quality and ensure volume compared to using a small built-in speaker. It becomes possible. Further, as an antenna connected to an FM transmitter built in a portable device, an externally attached rod-shaped antenna is known (for example, see Patent Document 2).

Patent Document 1: Japanese Unexamined Patent Publication No. 2001-197168 (Page 3-6, Fig. 1-5)

Patent Document 2: Japanese Patent Laid-Open No. 10-207972 (Pages 4-7, Fig. 1-9)

Disclosure of the invention

Problems to be solved by the invention

By the way, as disclosed in Patent Document 2 described above, when a rod-shaped antenna is always externally attached, there is a risk of damage during storage or transportation. Although there may be a case where such a rod-shaped antenna is built in, there is a problem that it becomes difficult to secure a space for storing the rod-shaped antenna in the housing as the apparatus becomes smaller.

[0004] The present invention was created in view of these points, and an object of the present invention is to provide a portable device with a built-in FM transmitter that can easily secure an antenna storage space with less risk of damage to the antenna. There is to do.

Means for solving the problem

[0005] In order to solve the above-described problems, a portable device incorporating an FM transmitter according to the present invention An audio signal generation circuit that generates an audio signal to be transmitted, a modulation circuit that generates a carrier wave signal that can be received by an FM receiver by FM modulation of the audio signal, and a transmission circuit that transmits a carrier wave signal through a transmission antenna And an audio signal generation circuit, a modulation circuit, and a transmission circuit are formed on one or a plurality of printed circuit boards, and a loop-shaped conductor formed along the inner peripheral surface of a housing that accommodates the print circuit board. Use as a transmitting antenna! Since the built-in loop-shaped conductor is used as a transmitting antenna, it is possible to prevent damage during storage or transportation where the transmitting antenna does not protrude outside the housing. Further, by using the space around the printed circuit board and along the inner peripheral surface of the housing as the storage space for the transmitting antenna, it is easy to secure a large storage space.

[0006] Further, the above-described casing is composed of first and second divided casings that are opened and closed according to the use state, and the loop-shaped conductor is one of the first and second divided casings. On the other hand, it is desirable that it be formed on the side that accommodates the printed circuit board on which the transmission circuit is mounted. This facilitates the connection between the transmission circuit and the transmission antenna, and simplifies the work process for wiring as well as the wiring itself.

[0007] In addition, the above-described housing is composed of first and second divided housings that are opened and closed according to the use state, and the loop conductors are respectively provided in the first and second divided housings. It is desirable that it be installed corresponding to As a result, a large transmission antenna can be realized with the first and second divided housings opened.

[0008] In addition, the loop-shaped conductors corresponding to the first and second divided casings described above have the same direction of the flowing current when the first and second casings are closed. It is desirable that they are connected in series. As a result, even when the casing is folded and two loop conductors overlap, these loop conductors can function effectively as a transmitting antenna.

[0009] The loop-shaped conductor described above is preferably a thin-film metal conductor formed on the inner peripheral surface of the casing. As a result, the storage space for the transmission antenna can be minimized, and the portable device incorporating the transmission antenna can be miniaturized.

Brief Description of Drawings O

FIG. 1 is a diagram showing a configuration of a portable music playback device according to an embodiment.

[Figure 1-

〇 2] A perspective view showing the external appearance of the portable music player.

FIG. 3 is a plan view showing the inside of the housing.

FIG. 4 is a perspective view showing an inner peripheral surface of the housing.

FIG. 5 is a view showing a modification of the loop-shaped conductor formed on the inner peripheral surface of the housing.

FIG. 6 is an external perspective view of a portable music player having two divided casings.

FIG. 7 is an external perspective view of a portable music player having two divided housings.

FIG. 8 is a diagram showing a connection state of loop conductors provided corresponding to each of two divided housings.

Explanation of symbols

Audio playback device

12 Output circuit

20 FM transmitter

22 Stereo modulation circuit

24 FM modulation circuit

26 Transmitter circuit

30 Operation unit

32 Display

34 Control unit

40 Transmit antenna

40A, 40B, 40C, 40D Loop conductor

100 Portable music player

200 PCB

300 cases

300A, 300B split housing

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, a portable music player according to an embodiment to which the present invention is applied will be described in detail with reference to the drawings. FIG. 1 is a diagram illustrating a configuration of a portable music playback device according to an embodiment. A portable music playback device 100 of the present embodiment shown in FIG. 1 includes an audio playback device 10, an output circuit 12, an FM transmitter 20, an operation unit 30, a display unit 32, and a control unit 34. Among these configurations, most configurations except the operation unit 30 and the display unit 32 are formed as a plurality of components or one-chip components on a semiconductor substrate using a CMOS process or a MOS process (however, these components are not included). Excluding drive mechanisms that cannot be formed by processes). By using these processes, the components formed on the semiconductor substrate and the portable music player 100 as a whole can be reduced in size and power consumption.

[0014] The audio playback device 10 is an audio signal generation circuit that expands audio data recorded in a compressed format and plays back and outputs an audio signal. For example, an MP3 (MPEG Audio Layer-3) player or an MD (Mini-disc) Compatible with players. Note that the audio playback device 10 according to the present embodiment needs at least a function for generating an audio signal to be transmitted, and is a CD (compact disc) player that plays an audio signal from uncompressed audio data or a portable device. The audio playback device 10 may be configured by a voice playback circuit such as a telephone. From the audio playback device 10, the left and right audio signals L and R are output separately. The output circuit 12 outputs a signal obtained by amplifying the audio signal output from the audio playback device 10 or adjusting the sound quality to an earphone (not shown) via the earphone terminal 106.

[0015] FM transmitter 20 transmits a signal obtained by performing FM modulation on the L signal and R signal output from audio reproduction device 10 from transmitting antenna 40. For this purpose, the FM transmitter 20 includes a stereo modulation circuit 22, an FM modulation circuit 24, and a transmission circuit 26. The stereo modulation circuit 22 performs a stereo modulation process that combines the input L signal and R signal to generate a stereo composite signal (stereo composite signal). The FM modulation circuit 24 performs FM modulation processing on the stereo composite signal and generates a carrier wave signal that can be received by an external FM receiver (not shown) installed in the vicinity of the portable music player 100. To do. The transmission circuit 26 amplifies the carrier wave signal generated by the FM modulation circuit 24 and transmits it from the transmission antenna 40.

[0016] The operation unit 30 is provided with various keys and operation knobs in order to accept operations by the user. I have. For example, a “play” key and a “stop” key are provided to give various instructions to the playback operation of the audio signal by the audio playback device 10, and a volume is used to indicate the degree of amplification of the output circuit 12. It has “UP” key and “DOWN” key for setting. The display unit 32 displays the content of operations performed by the operation unit 30 and the content reproduced by the audio playback device 10 (for example, the name of the song being played (song name), the name of the artist who has sung this song, the elapsed playback time, etc.), etc. Is displayed. The control unit 34 controls the entire portable music player 100. For example, the playback state by the audio playback device 10 is set, or the volume is set by using the output circuit 12.

FIG. 2 is a perspective view showing the external appearance of the portable music playback device 100. As shown in FIG. 2, a printed circuit board 200 in which the components shown in FIG. 1 are mounted and wired is housed in the housing 300 of the portable music player 100.

FIG. 3 is a plan view showing the inside of the housing 300. FIG. 4 is a perspective view showing the inner peripheral surface of the housing 300. 3 and 4 show a state where the top surface of the housing 300 (one surface corresponding to a lid) is removed. As shown in FIG. 3, one or a plurality of components 212, 214, and 216 is mounted on the printed circuit board 200 to achieve each configuration of the portable music playback device 100 shown in FIG. In the example shown in Fig. 3, the forces shown in the three parts 212, 214, and 216 are realized using two or more parts, or each part is used as a whole. May be realized.

In addition, a loop-shaped conductor 40A that circulates along the surface is formed on the inner peripheral surface (side surface) of the housing 300, and this loop-shaped conductor 40A is used as the transmitting antenna 40. . The loop-shaped conductor 40A is a thin-film metal conductor formed on a peripheral side surface 302 perpendicular to the surface on which the printed circuit board 200 is arranged, and an end portion of the loop-shaped conductor 40A is mounted on the printed circuit board 200. And is connected via Jiyampa line. In FIG. 3, for the sake of clarity, the film thickness of the loop conductor 40A formed on the side surface 302 of the housing 300 is shown thick. Further, the loop conductor 40A and the transmission circuit 26 may be connected by a method other than the jumper line. For example, the thin-film metal conductor used to form the loop-shaped conductor 40A is extended to a position where it overlaps the printed circuit board 200, and is in direct contact with the pattern conductor formed on the back surface of the printed circuit board 200 for connection. May be. As described above, in the portable music playback device 100 of the present embodiment, since the built-in loop conductor 4 OA is used as the transmission antenna 40, the transmission antenna 40 may protrude outside the housing 300. It is possible to prevent damage during storage and transportation. Further, by using the space along the inner peripheral surface of the housing 300 as the storage space for the transmission antenna 40, it is easy to secure the storage space.

FIG. 5 is a view showing a modification of the loop-shaped conductor formed on the inner peripheral surface of the housing 300.

In the example shown in FIG. 4, the loop-shaped conductor 40A is formed on the surface of the side surface 302 that is perpendicular to the bottom surface on which the printed circuit board 200 is mounted. On the other hand, the loop conductor 40 B shown in FIG. 5 is formed near the outer periphery (along the outer periphery) of the bottom surface 304 as the inner peripheral surface other than the side surface 302 of the housing 300. The connection between the loop conductor 40B and the transmission circuit 26 is the same as that of the loop conductor 40A shown in FIGS. 3 and 4, and is connected via a jumper wire or the like. Since the loop-shaped conductor 40B is formed on the surface of the bottom surface 304 on which the printed board 200 is mounted, the connection between the transmission circuit 26 on the printed board 200 and the loop-shaped conductor 40B becomes easy.

[0022] It should be noted that the present invention is not limited to the above embodiment, and various modifications can be made within the scope of the gist of the present invention. For example, in the above-described embodiment, the portable music playback device 100 having the single casing 300 has been described, but the present invention can also be applied to a portable music playback device having a plurality of divided casings.

6 and 7 are external perspective views of a portable music playback device having two divided housings. FIG. 6 shows a state force when the two divided casings 300A and 300B are opened. FIG. 7 shows a state where the two divided casings 300A and 300B are closed. The loop-shaped conductor 40A as the transmission antenna 40 is formed on either side of the two divided housings 300A and 300B and on the side that accommodates the printed circuit board 200 on which the transmission circuit 26 is mounted. This facilitates the connection between the transmission circuit 26 and the transmission antenna 40, and simplifies the work process for wiring as well as the wiring itself.

Alternatively, a loop conductor may be provided corresponding to each of the two divided housings 300A and 300B. As a result, a large transmitting antenna can be realized with the two divided casings 300A and 300B opened. FIG. 8 is a diagram showing a connection state of loop conductors provided corresponding to the two divided casings 300A and 300B. Loop conductors 40B and 40C are formed along the inner peripheral surface of one divided housing 300A, and these loop conductors 40B and 40C are connected to the transmission circuit 26. Further, a loop-shaped conductor 40D is formed along the inner peripheral surface of the other divided casing 300B. These loop conductors 40B, 40C, and 40D are connected so that their ends cross each other (as shown in FIG. 8, a conductor having an overall figure 8 shape is formed). By making such a connection, when the two divided casings 300A and 300B are folded, the directions of the currents flowing through the respective loop conductors can be made the same, and these loop conductors 40B, 40C and 40D Can effectively function as a transmitting antenna 40 with two loops.

In the example shown in FIG. 4 or FIG. 5, the number of turns of the loop conductor (the number of loops) is 1, but the number of turns may be 2 or more. Alternatively, loop-shaped conductors may be formed on both the side surface 302 shown in FIG. 4 and the bottom surface 304 shown in FIG.

Industrial applicability

[0027] According to the present invention, since the built-in loop-shaped conductor is used as a transmission antenna, it is possible to prevent damage during storage or transportation that prevents the transmission antenna from protruding outside the housing. . Further, by using the space around the printed circuit board and along the inner peripheral surface of the housing as the storage space for the transmitting antenna, it is easy to secure a large storage space.

Claims

The scope of the claims

[1] an audio signal generation circuit for generating an audio signal to be transmitted;

A modulation circuit for FM-modulating the audio signal to generate a carrier wave signal that can be received by an FM receiver;

A transmission circuit for transmitting the carrier signal through a transmission antenna;

The audio signal generation circuit, the modulation circuit, and the transmission circuit are formed on one or a plurality of printed circuit boards and a loop formed along an inner peripheral surface of a housing that houses the printed circuit boards A portable device with a built-in FM transmitter that uses a shaped conductor as the transmitting antenna.

[2] In claim 1,

The casing has first and second divided casing forces that are opened and closed according to usage conditions.

The loop-shaped conductor is one of the first and second divided housings, and is formed on the side that accommodates the printed circuit board on which the transmission circuit is mounted. A portable device with a built-in FM transmitter .

[3] In claim 1,

The looped conductor is provided corresponding to each of the first and second divided housings, and is a portable device with a built-in FM transmitter.

[4] In claim 3,

The loop-shaped conductors corresponding to the first and second divided casings are connected in series so that the directions of the currents flowing when the first and second casings are closed are the same. Mobile device with built-in FM transmitter.

[5] In claim 1,

The loop-shaped conductor is a thin-film metal conductor formed on the inner peripheral surface of the housing.

[6] In claim 1, The loop-shaped conductor is a portable device with a built-in FM transmitter formed on the surface of a side surface orthogonal to the bottom surface of the housing on which the printed board is mounted.

[7] In claim 1,

The loop-shaped conductor is formed along the outer periphery of the bottom surface of the casing on which the printed board is mounted, and is a portable device with a built-in FM transmitter.

[8] In claim 1,

A CMOS process is! / Is a portable device with a built-in FM transmitter in which a structure corresponding to the audio signal generation circuit, the modulation circuit, and the transmission circuit is formed on a semiconductor substrate using a MOS process.

[9] In claim 1,

The audio signal generation circuit is an MP3 player, a portable device with a built-in FM transmitter.

[10] In claim 1,

The audio signal generation circuit is an MD player, a portable device with a built-in FM transmitter.

[11] In claim 1,

The audio signal generation circuit is a CD player.

[12] In claim 1,

The audio signal generation circuit is a mobile phone.