WO2003026157A1

WO2003026157A1 - Antenna sharer

Info

Publication number: WO2003026157A1
Application number: PCT/JP2002/006117
Authority: WO
Inventors: Hajime Shimada
Original assignee: Matsushita Electric Industrial Co., Ltd.
Priority date: 2001-09-18
Filing date: 2002-06-19
Publication date: 2003-03-27
Also published as: JP2003092541A

Abstract

An antenna sharer uses a dielectric filter (11) at a transmission side and a SAW filter (12) at a reception side. Interference of the reception side filter to the transmission side filter due to use of different types of filters is adjusted by a phase adjuster (16). This minimizes power loss of a transmission signal and lowering of reception sensitivity. That is, the transmission power loss is reduced by phase adjustment by the phase adjuster (16) and lowering of the reception sensitivity is reduced by using only the SAW filter at the reception side.

Description

Description Antenna duplexer <Technical field>

The present invention relates to an antenna duplexer suitable for use in a wireless communication device that performs simultaneous transmission and reception.

2. Description of the Related Art Conventionally, an antenna duplexer that enables simultaneous transmission and reception of radio signals with a common antenna has been used in a wireless communication device that supports simultaneous transmission and reception. In general, S AW (Surface Acoustic Wave) filters and dielectric filters are used for antenna duplexers. S AW filters have the advantage of large attenuation outside the band, but have the disadvantage of large insertion loss within the band. On the other hand, dielectric filters have the advantage of low insertion loss in the band, but have the disadvantage of low attenuation outside the band.

Fig. 6 is a block diagram showing the schematic configuration of a radio unit equipped with a conventional antenna duplexer 10 using a dielectric filter 11 on the transmitting side and a SAW filter 12 on the receiving side. It is. FIG. 7 is a block diagram showing a schematic configuration of a radio unit including a conventional antenna duplexer 20 using a SAW filter 12 on both the transmitting side filter and the receiving side filter. Fig. 8 shows a conventional antenna duplexer 30 that uses a dielectric filter 11 in which a dielectric filter 11 is connected in series with a filter on the transmitting side and a filter 12 is connected in series with the filter on the receiving side. FIG. 3 is a block diagram illustrating a schematic configuration of a wireless unit in which the present invention is performed. In the radio section in Fig. 6, after the input transmission signal is amplified by the transmission power amplifier 13, the reception band noise is reduced by the dielectric filter 11 on the transmission side of the antenna duplexer 10. And transmit from the transmit / receive shared antenna 13. On the other hand, the radio signal (received signal) captured by the shared antenna 13 is used to reduce the interference wave and reduce the transmitted wave at the SAW filter 12 on the receiving side of the antenna duplexer 10 to reduce the transmission power. Enter 5 In the radio section in Fig. 7, after the input transmission signal is amplified by the transmission power amplifier 14, the reception band noise is reduced by the S AW filter 12 on the transmission side of the antenna duplexer 20. Transmit from antenna 13 for transmission and reception. On the other hand, the radio signal captured by the shared antenna 13 is input to the receiving power amplifier 15 with the attenuation of the interfering wave and the transmission wave reduced by the SAW filter 12 on the receiving side of the antenna duplexer 20. .

In the radio unit in FIG. 8, after the input transmission signal is amplified by the transmission power amplifier 14, the noise in the reception band is reduced by the dielectric filter 11 on the transmission side of the antenna duplexer 30. Transmit from the transmitting / receiving antenna 13. On the other hand, the radio signal captured by the transmission / reception shared antenna 13 is reduced by the dielectric fill filter 11 and the SAW fill filter 12 on the receiving side of the antenna duplexer 30 to reduce the interfering wave and the transmission wave, so that the reception power amplifier 1 Enter in 5. By the way, the above-described conventional antenna duplexers 10, 20, 30 have the following problems.

First, the antenna duplexer 10 uses different filters for transmission and reception (using a dielectric filter 11 for transmission and a SAW filter 12 for reception). There is a problem that the power loss of the transmission signal is large and the power consumption is large due to interference with the transmitting side filter in the evening. That is, the transmission band impedance of the S AW filter 12 on the receiving side is as shown in the Smith chart of FIG. 9, and the transmission of the dielectric filter 11 on the transmitting side is caused by the interference of the filtering on the receiving side. Since the band impedance is as shown in the Smith chart of Fig. 10, the transmission characteristic of the dielectric filter 11 on the transmitting side increases as shown in Fig. 11 as shown in Fig. 11. . Next, since the antenna duplexer 20 uses the SAW filter 12 for both transmission and reception, the problem similar to the antenna duplexer 10 described above is unlikely to occur, but the SAW filter 12 itself is inserted. Since the loss is large, it is necessary to increase the transmission power, and there is a problem that the power consumption increases.

Finally, the antenna duplexer 30 uses the dielectric fill 11 for transmission, so power consumption can be reduced because the insertion loss is smaller than that of the SAW fill 12. Since a dielectric filter 11 and a SAW filter 11 are connected in series as a receiving filter, the insertion loss is larger than that of the receiving side of the antenna duplexer 20 described above. There is a problem that reception sensitivity is poor.

The present invention has been made in view of the above, and an object of the present invention is to provide an antenna duplexer that can reduce power consumption on a transmission side and minimize a decrease in reception sensitivity.

An antenna duplexer according to claim 1 according to the present invention for achieving the above object, comprising: a transmitting-side filter that supplies a transmission signal from a radio transmission unit to a transmission / reception antenna; and a reception filter captured by the transmission / reception antenna. An antenna duplexer for transmitting a signal to a wireless reception unit at the reception side, wherein the transmission signal and the reception signal are passed at the same time. While the filter is composed of a SAW filter, a phase adjuster (phase adjuster 16) for suppressing interference of a reception signal with a transmission signal by the dielectric filter and the SAW filter is provided. And

According to the above configuration, the dielectric filter is used on the transmitting side, the SAW filter is used on the receiving side, and the transmitting side filter of the receiving side filter is used by using these kinds of different filters. Since the interference to the evening is adjusted by the phase adjusting means, it is possible to minimize the power loss of the transmission signal and the decrease in the receiving sensitivity. That is, the transmission power loss is reduced by the phase adjustment by the phase adjustment means, and the decrease in the receiving sensitivity due to using only the Saw filter on the receiving side is reduced.

Further, in the antenna duplexer according to claim 2 of the present invention, in the antenna duplexer according to claim 1, when a setting not to perform simultaneous transmission and reception is performed, the dielectric filter is connected to a circuit, It is characterized by comprising bypass means (switch control section 20, switch 17, 18, 19) for mechanically or electrically separating from the transmission signal transmission path.

According to the above configuration, simultaneous transmission and reception are not performed (for example, only voice transmission is performed). In this case, since the dielectric filter on the transmitting side is removed from the transmission signal transmission path, the transmission power loss due to the dielectric filter is eliminated, and the power consumption can be reduced accordingly.

When bucket service is performed in the TDMA system, transmission and reception operate simultaneously, but only transmission operates when voice service is supported.Therefore, a filter is required between the transmission / reception shared antenna and the transmission power amplifier. do not do. Therefore, when the voice service is supported, the transmission power loss due to the dielectric filter is eliminated by removing the dielectric filter on the transmitting side from the circuit, and the power consumption can be reduced accordingly.

<Brief description of drawings> ''

FIG. 1 is a block diagram showing a configuration of a radio unit having an antenna duplexer according to Embodiment 1 of the present invention.

FIG. 2 is a Smith chart showing a transmission band impedance characteristic of a receiving SAW filter in the antenna duplexer according to the first embodiment.

FIG. 3 is a Smith chart showing the transmission band impedance characteristics of the transmission-side dielectric filter of the antenna duplexer according to Embodiment 1.

FIG. 4 is a diagram illustrating passband characteristics of the transmitting-side dielectric filter of the antenna duplexer according to the first embodiment.

FIG. 5 is a block diagram showing a configuration of a radio unit having an antenna duplexer according to Embodiment 2 of the present invention.

FIG. 6 is a block diagram showing a configuration of a radio unit having a conventional antenna duplexer. FIG. 7 is a block diagram showing a configuration of a radio unit having a conventional antenna duplexer. FIG. 8 is a block diagram showing a configuration of a radio unit including a conventional antenna duplexer. FIG. 9 is a Smith chart showing the transmission band impedance characteristic of the receiving SAW filter in the conventional antenna duplexer shown in FIG.

FIG. 10 is a Smith chart showing the transmission band impedance characteristics of the transmission-side dielectric filter in the antenna duplexer shown in FIG.

FIG. 11 is a diagram illustrating passband characteristics of the transmission-side dielectric filter in the antenna duplexer illustrated in FIG. In the figure, reference numeral 11 denotes a dielectric filter, 12 denotes a SAW filter, 13 denotes a transmission / reception antenna, 14 denotes a transmission power amplifier, 15 denotes a reception power amplifier, and 16 denotes a position. The phase adjusters, 17, 18, and 19 are switching switches, 20 is a switching control unit, and 40 and 50 are antenna duplexers.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)

FIG. 1 is a block diagram showing a configuration of a radio section having an antenna duplexer according to Embodiment 1 of the present invention. In this figure, parts having the same functions as in FIG. 6 are denoted by the same reference numerals.

In FIG. 1, an antenna duplexer 40 according to the present embodiment includes a dielectric filter 11 as a transmitting-side filter, a SAW filter 12 as a receiving-side filter, and a dielectric filter 12. And a phase adjuster 16 for preventing the reception-side filter from interfering with the transmission-side filter due to the use of the receiver-side filter 11 and the SAW filter 12. The phase adjuster 16 is arranged in front of the SAW filter 12 on the receiving side (transmitting and receiving antenna 13 side).

Fig. 2 is a Smith chart showing the transmission band impedance characteristics of the S AW filter 12 on the receiving side whose phase has been adjusted by the phase adjuster 16, and Fig. 3 is the Smith chart showing the transmission side whose phase has been adjusted by the phase adjuster 16. 6 is a Smith chart showing the transmission band impedance characteristics of the dielectric filter 11 of FIG. FIG. 4 is a diagram showing a pass band of the dielectric filter 11 on the transmission side. It can be seen that the transmission power loss is smaller than in the passband of the transmission-side dielectric filter 11 in the conventional antenna duplexer 10 shown in FIG.

The transmission / reception operation of the radio unit having the antenna duplexer 40 is similar to that of the radio unit of FIG. 6, after the input transmission signal is amplified by the transmission power amplifier 14 and then transmitted by the dielectric filter. 1 Reduce the reception band noise in 1 And send it. On the other hand, the radio signal captured by the shared antenna 13 for transmission and reception is input to the reception power amplifier 15 after the attenuation of the interference wave and the transmission wave are reduced by the SAW filter 12 on the reception side.

As described above, according to the antenna duplexer 40 of the present embodiment, the dielectric fill layer 11 as the transmitting side fill area, the S AW fill area 12 as the receive side fill area, and the dielectric fill Since a phase adjuster 16 is provided to prevent the reception filter from interfering with the transmission filter due to the use of the filter 11 and the S AW filter 12, the transmitter 16 The power consumption can be reduced, and the reduction in reception sensitivity can be minimized.

(Embodiment 2)

FIG. 5 is a block diagram showing a configuration of a radio section having an antenna duplexer according to Embodiment 2 of the present invention. In this figure, parts having the same functions as those in FIGS. 1 and 6 are denoted by the same reference numerals.

The antenna duplexer 50 of the present embodiment is a switching switch 17 that switches the shared transmission / reception antenna 13 to the transmission side when performing only the transmission operation without performing the simultaneous transmission / reception operation, such as when only the voice transmission supports the line voice service. Switching switches 18 and 19 for removing the transmission-side dielectric filter 11 from the circuit, that is, the transmission signal transmission path, and a switching control unit 20 for controlling the switching of these switching switches 17 to 19. are doing.

When performing packet service in the TD MA (Time Division Multiple Access) method, transmission and reception are performed simultaneously, but only transmission is performed when voice service is supported. Therefore, the transmission / reception shared antenna 13 and the transmission power amplifier 1 are used. No need for a Phil evening between 4. Therefore, when simultaneous transmission and reception are not performed, such as when supporting voice services, removing the dielectric filter 11 from the circuit eliminates the loss of transmission power due to the dielectric filter 11, thereby reducing power consumption. . As described above, according to the antenna duplexer 50 of the present embodiment, when simultaneous transmission and reception are not performed, for example, when only voice transmission is performed, the switching control unit 20 switches the switching switches 17 to 19. Control to remove the dielectric film on the transmitting side from the circuit. Therefore, the transmission power loss due to the dielectric filter 11 is eliminated, and the power consumption can be reduced accordingly.

In the second embodiment, the dielectric filter 11 on the transmitting side is detached from the circuit by using the switching switches 18 and 19 having a mechanical structure. A typical switching switch may be used. Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.

This application is based on a Japanese patent application filed on Sep. 18, 2001 (Japanese Patent Application No. 2001-283309), the contents of which are incorporated herein by reference. Industrial applicability>

As described above, according to the present invention, a dielectric filter is provided as a transmitting filter, a S AW filter is provided as a receiving filter, and a dielectric filter and a S AW filter are used. Phase adjustment means to prevent interference of the receiving filter with the transmitting filter, which can reduce the power consumption on the transmitting side and minimize the reduction in receiving sensitivity. An antenna sharing device that can be provided. ·

In addition, when simultaneous transmission and reception are not performed, for example, when only voice transmission is performed, the dielectric filter on the transmitting side is removed from the circuit, so that the transmission power loss due to the dielectric filter is eliminated, and the power consumption is reduced accordingly. An antenna duplexer that can be reduced can be provided.

Claims

The scope of the claims

1. A transmission filter that supplies a transmission signal from a wireless transmission unit to a transmission / reception shared antenna, and a reception filter that supplies a reception signal captured by the transmission / reception antenna to a wireless reception unit. And the antenna duplexer for simultaneously passing the received signal,

The transmission-side filter is composed of a dielectric filter, and the reception-side filter is composed of a SAW filter. An antenna duplexer having a phase adjusting means for suppressing interference.

2. The apparatus according to claim 1, further comprising: bypass means for mechanically or electrically disconnecting the dielectric filter from a transmission signal transmission path when the setting for not performing the simultaneous transmission and reception operation is performed. The antenna duplexer described.