JP5596863B2 - Antenna duplexer - Google Patents

Description

  The present invention relates to an antenna duplexer used in a base station apparatus or the like.

  In a radio circuit for a radio communication system that employs a frequency duplex system, a duplexer is generally used immediately below an antenna in order to separate transmitted and received waves. The duplexer needs to achieve low insertion loss in the transmission band and the reception band while achieving high isolation between transmission and reception. Moreover, it is necessary to endure a high transmission output in the transmission band. For example, in a 2 GHz band mobile communication base station apparatus, a duplexer having a maximum transmission output of 20 W, a frequency difference between transmission and reception bands of 190 MHz, and an isolation between transmission and reception of at least 80 dB or more is used. In order to achieve high breakdown voltage and steep out-of-band attenuation characteristics, a cavity resonator is used for the duplexer. A multiband duplexer that uses a plurality of duplexers requires a circuit that synthesizes a plurality of duplexer outputs in a tournament configuration or a parallel configuration. In general, since a low pass loss is required for a duplexer, a 3 dB power combiner cannot be used. Therefore, it is necessary to use a plurality of filters.

  A conventional dual-band antenna duplexer will be described with reference to FIG. FIG. 1 is a diagram illustrating a configuration example of a dual-band antenna duplexer 800 corresponding to a 800 MHz band and a 2 GHz band in the prior art. The antenna duplexer 800 includes an 800 MHz band / 2 GHz band dual band duplexer 811, an 800 MHz band duplexer 821, and a 2 GHz band duplexer 822 that separates the 800 MHz band and the 2 GHz band. The 800 MHz band / 2 GHz band dual band duplexer 811 includes a first input / output terminal 811-1, a second input / output terminal 811-2, and a third input / output terminal 811-3. The 800 MHz band duplexer 821 includes an input / output terminal 821-1, a transmission terminal 821-2, and a reception terminal 821-3. The 2 GHz band duplexer 822 includes an input / output terminal 822-1, a transmission terminal 822-2, and a reception terminal 822-3. In the configuration of FIG. 1, the passband can be made low loss.

  Next, a conventional triple-band antenna duplexer will be described with reference to FIG. FIG. 2 is a diagram showing a configuration example of an antenna duplexer 900 corresponding to a triple band of 800 MHz band, 1.5 GHz band, and 2 GHz band in the prior art. The antenna duplexer 900 includes an 800 MHz to 1.5 GHz band / 2 GHz band dual band duplexer 911 that separates the 800 MHz band from the 1.5 GHz band and the 2 GHz band, and an 800 MHz band / 1. A 5 GHz band dual band duplexer 921, an 800 MHz band duplexer 931, a 1.5 GHz band duplexer 932, and a 2 GHz band duplexer 933 are provided. The 800 MHz to 1.5 GHz band / 2 GHz band dual band duplexer 911 includes a first input / output terminal 911-1, a second input / output terminal 911-2, and a third input / output terminal 911-3. The 800 MHz band / 1.5 GHz band dual band duplexer 921 includes a first input / output terminal 921-1, a second input / output terminal 921-2, and a third input / output terminal 921-3. The 800 MHz band duplexer 931 includes an input / output terminal 931-1, a transmission terminal 931-2, and a reception terminal 931-3. The 1.5 GHz band duplexer 932 includes an input / output terminal 932-1, a transmission terminal 932-2, and a reception terminal 932-3. The 2 GHz band duplexer 933 includes an input / output terminal 933-1, a transmission terminal 933-2, and a reception terminal 933-3. As a configuration similar to FIG. Five bands of 1.2276 GHz and 1.57542 GHz using GPS, 2.45 GHz and 5.2 GHz using wireless LAN, and 5.8 GHz using DSRC are combined in a tournament form using a duplexer. In order to synthesize a plurality of bands, it is common to configure a duplexer in a tournament form in multiple stages as in Patent Document 1.

  In Patent Document 2, a two-notch filter is used as an antenna sharing device that supports wireless communication modes of duplex, two-wave simplex, and one-wave simplex. In this configuration, the notch filter of the transmission unit blocks the operation band of the reception unit, and the notch filter of the reception unit blocks the operation band of the transmission unit. Patent Document 2 discloses that the antenna duplexer can be configured with a notch filter.

JP 2008-278059 A JP 2008-11198 A

  Today, mobile communication base station devices are required to be small and lightweight. There are a plurality of frequency bands supported by the mobile communication base station apparatus. Conventionally, the apparatus is configured in each frequency band, but in the future, it is necessary to integrate a plurality of apparatuses due to the installation space. At this time, as described above, it is assumed that the multiband-compatible antenna duplexer requires a corresponding size, and thus the multiband-compatible antenna duplexer needs to be reduced in size and weight.

  However, an antenna duplexer that is embodied by configuring a plurality of duplexers in a tournament format as described above generally has considerable dimensions, although it depends on the frequency characteristics of each duplexer. For example, in the case of a mobile communication base station antenna duplexer, each duplexer has dimensions of about 20 cm in length, 10 cm in width, and about 5 cm in height. In the case of a dual-band compatible antenna duplexer, since three such duplexers are used, it is expected to have a corresponding size. Moreover, it can be easily analogized that the size of the multiband-compatible antenna duplexer to be embodied increases as the number of supported bands increases.

  There is a method using a power combiner to combine a plurality of duplexer outputs having different operating frequency bands, but the insertion loss increases as the number of duplexers to be connected increases. In addition, since the power combiner consumes power corresponding to the number of combined terminals in the termination resistor, the duplexer output has an apparent increase in insertion loss (distribution loss).

  Conventionally, a SAW filter is known as a small filter. However, in order to realize the steep out-of-band attenuation characteristic required in a mobile communication base station duplexer by the SAW filter, an increase in insertion loss and delay time deviation is allowed. Therefore, it is difficult to apply the SAW filter to the mobile communication base station duplexer as it is.

  An example of using a notch filter as an antenna duplexer as in Patent Document 2 is known, and the size of the notch filter is smaller than that of a duplexer. However, since the conventional notch filter can only block signals in a narrow band and a single frequency band, it cannot be used for a multiband antenna duplexer that supports a plurality of frequency bands. In order to configure an antenna duplexer that can be used in multiple frequency bands with only a notch filter, the notch filter must have characteristics that block signals in multiple frequency bands, and characteristics that block signals in a wider band than before. is there. However, such a notch filter has an insufficient blocking amount, and it has not been possible to realize a multiband antenna duplexer by configuring only the notch filter in a tournament system.

  Therefore, an object of the present invention is to provide a small and lightweight multiband-compatible antenna duplexer while achieving frequency characteristics equivalent to those of the prior art.

In the antenna duplexer of the present invention, a distributor that distributes signals and a notch filter that suppresses a desired frequency band of the distributed signals are alternately connected in cascade. P is an integer of 1 or more, Q and R are integers of 2 or more, and the first input / output terminal, the second input / output terminal, and the third input / output terminal are provided. A frequency band passing through the third input / output terminal is an open condition, and a frequency band passing through the second input / output terminal when viewed from the first input / output terminal to the third input / output terminal is an open condition; , First to Q-th notch filters including first input / output terminals and second input / output terminals, and first to R-th duplexers including input / output terminals, transmission terminals, and reception terminals.

The first input / output terminal of the first distributor is an antenna element, the second input / output terminal of the first distributor is the first input / output terminal of the first notch filter, and the third input / output terminal of the first distributor is the second input terminal . Connected to the first input / output terminal of the 2- notch filter. If P is an integer of 2 or more, the p is 2 or more P an integer, the first input-output terminal of the first p distributor and the second output terminal of the (p-1) Bruno notch filter, the p second input and output terminals of the distributor and the first output terminal of the (2p-1) Bruno notch filter, a third input terminal of the p divider is connected to the first output terminal of the 2p Roh notch filter . Among the first to Q-th notch filters, the second input / output terminals of the R notch filters that belong to the end as viewed from the antenna element are connected to the input / output terminals of the first to R-th duplexers. The transmission terminals of the first to R-th duplexers are connected to the transmission circuit, and the reception terminals are connected to the reception circuit. The notch filter connected to the second input / output terminal of any distributor blocks signals in the frequency band input to all duplexers connected to the third input / output terminal of the distributor via the notch filter. . The notch filter connected to the third input / output terminal of any distributor blocks the signal in the frequency band input to all duplexers connected to the second input / output terminal of the distributor via the notch filter. .

  According to the antenna duplexer of the present invention, it is possible to realize a small and lightweight multi-band compatible antenna duplexer while achieving the same frequency characteristics as before.

The figure which shows the structural example of the antenna sharing device corresponding to the dual band of 800 MHz band and 2 GHz band in a prior art. The figure which shows the structural example of the antenna sharing device corresponding to the triple band of 800 MHz band in a prior art, 1.5 GHz band, and 2 GHz band. The figure explaining the principal point of the antenna sharing device (dual band correspondence) of this invention. The figure explaining the principal point of the antenna sharing device (triple band correspondence) of this invention. The figure which shows the structure of the antenna sharing device concerning Example 1. FIG. The figure which shows the structural example of the notch filter used for the antenna sharing device of this invention. The figure which shows the simulation result of the notch filter which uses FIG. 6 as a basic circuit. The figure which shows the structure of the antenna sharing device concerning Example 2. FIG. The figure which shows the structural example of the notch filter used for the antenna sharing device of this invention. The figure which shows the simulation result of the notch filter which uses FIG. 9 as a basic circuit. The figure which shows the structure of the antenna sharing device concerning Example 3. FIG. The figure which shows the structure of the antenna sharing device concerning Example 4. FIG. The figure which shows the structure of the antenna sharing device concerning Example 5. FIG. The figure which shows the structure of the antenna sharing device concerning Example 6. FIG. The figure which shows the example which comprised the antenna sharing device of Example 6 by the planar circuit. The figure which shows the linear simulation result by a microwave circuit simulator about the example which comprised the antenna sharing device of Example 6 by the planar circuit. The figure which shows the structure of the antenna sharing device concerning the modification 1. FIG.

  Hereinafter, embodiments of the present invention will be described in detail. In addition, the same number is attached | subjected to the structure part which has the same function, and duplication description is abbreviate | omitted.

<Points of the present invention>
The points of the present invention will be described below with reference to FIGS. FIG. 3 is a diagram for explaining the essential points of the antenna duplexer (dual band compatible) of the present invention. FIG. 4 is a diagram for explaining the main points of the antenna duplexer (corresponding to a triple band) according to the present invention. In the antenna duplexer of the present invention, a notch filter is used in a circuit that synthesizes a plurality of duplexers. For example, in the case of a dual-band compatible antenna duplexer corresponding to two frequencies, notch filter 1 and notch filter 2 which are two notch filters having different frequency stop bands as shown in FIG. 3 are used. In a duplexer corresponding to a triple band or more, as shown in FIG. 4, a notch filter is formed by a tournament synthesis type. The antenna duplexer of the present invention uses a notch filter having a plurality of attenuation poles and enabling a wide band and a high rejection. As compared with a circuit using a conventional duplexer as in Patent Document 1, a circuit using a notch filter can suppress the insertion loss of the passband while suppressing the frequency band to be blocked. A circuit using a notch filter does not halve the passing power unlike a 3 dB power divider. In addition, the group delay time deviation of the pass band can be extremely reduced as compared with the band pass filter. Moreover, since the antenna duplexer of the present invention is provided with a conventional duplexer for each frequency band, it is possible to obtain a sufficient amount of blocking that cannot be realized with only a notch filter.

  The dual-band antenna duplexer according to the first embodiment will be described below with reference to FIG. FIG. 5 is a diagram illustrating the configuration of the antenna duplexer 100 according to the present embodiment.

  The antenna duplexer 100 of this embodiment includes a T distributor 111, a 2 GHz band notch filter 121, a 1.7 GHz band notch filter 122, a 1.7 GHz band duplexer 131, and a 2 GHz band duplexer 132 as distributors. . The T distributor 111 includes a first input / output terminal 111-1, a second input / output terminal 111-2, and a third input / output terminal 111-3. The 2 GHz band notch filter 121 includes a first input / output terminal 121-1 and a second input / output terminal 121-2. The 1.7 GHz band notch filter 122 includes a first input / output terminal 122-1 and a second input / output terminal 122-2. The 1.7 GHz band duplexer 131 includes an input / output terminal 131-1, a transmission terminal 131-2, and a reception terminal 131-3. The 2 GHz band duplexer 132 includes an input / output terminal 132-1, a transmission terminal 132-2, and a reception terminal 132-3. Also in the following embodiments, the T distributor is provided with first, second, and third input / output terminals, and subscripts are (component number) -1, (component number) -2, (component) Number) -3, the first input / output terminal is the input / output terminal on the antenna terminal side, and the second and third input / output terminals are the input / output terminals on the transmission / reception circuit side. Similarly, in the following embodiments, the notch filter is provided with first and second input / output terminals, and the subscripts are represented as (component number) -1 and (component number) -2, respectively. The first input / output terminal is an input / output terminal on the antenna terminal side, and the second input / output terminal is an input / output terminal on the transmission / reception circuit side. Similarly, in the following embodiments, the duplexer includes an input / output terminal, a transmission terminal, and a reception terminal, and subscripts are (component number) -1, (component number) -2, Part number) -3, the input / output terminal is an input / output terminal on the antenna terminal side and is connected to the notch filter, and the transmission terminal is a terminal connected to the transmission circuit (transmission system). It is assumed that the receiving terminal is a terminal connected to a receiving circuit (receiving system).

  The first input / output terminal 111-1 of the T distributor 111 is connected to the antenna element. The second input / output terminal 111-2 of the T distributor 111 is connected to the first input / output terminal 121-1 of the 2 GHz band notch filter 121. The third input / output terminal 111-3 of the T distributor 111 is connected to the first input / output terminal 122-1 of the 1.7 GHz band notch filter 122. The second input / output terminal 121-2 of the 2 GHz band notch filter 121 is connected to the input / output terminal 131-1 of the 1.7 GHz band duplexer 131. The second input / output terminal 122-2 of the 1.7 GHz band notch filter 122 is connected to the input / output terminal 132-1 of the 2 GHz band duplexer 132. A transmission terminal 131-2 of the 1.7 GHz band duplexer 131 is connected to a 1.7 GHz band transmission circuit, and a reception terminal 131-3 is connected to a 1.7 GHz band reception circuit. The transmission terminal 132-2 of the 2 GHz band duplexer 132 is connected to a 2 GHz band transmission circuit, and the reception terminal 132-3 is connected to a 2 GHz band reception circuit.

  The 2 GHz band notch filter 121 connected to the second input / output terminal 111-2 of the T distributor 111 is connected to the third input / output terminal 111-3 of the T distributor 111 via the 1.7 GHz band notch filter 122. In addition, the signal of the frequency band (2 GHz band) input to the 2 GHz band duplexer 132 is blocked. The 1.7 GHz band notch filter 122 connected to the third input / output terminal 111-3 of the T distributor 111 is connected to the second input / output terminal 111-2 of the T distributor 111 via the 2 GHz band notch filter 121. In addition, the signal of the frequency band (1.7 GHz band) input to the 1.7 GHz band duplexer 131 is blocked.

  The 1.7 GHz band duplexer 131 has a transmission frequency band of 1.860 GHz to 1.880 GHz, and a reception frequency band of 1.765 GHz to 1.785 GHz. Isolation between transmission and reception, that is, wraparound from the transmission band to the reception band is at least 100 dB or more. The insertion loss is 0.5 dB or less for each transmission / reception band. The breakdown voltage of the transmission band is at least 20 W or more. The 2 GHz band duplexer 132 has a transmission band of 2.130 GHz to 2.150 GHz and a reception band of 1.940 GHz to 1.960 GHz. The isolation between transmission and reception is at least 80 dB or more, and the insertion loss of each pass band is 0.5 dB or less. The breakdown voltage of the transmission band is at least 20 W or more. In order to enable such a high out-of-band attenuation characteristic and a high breakdown voltage, these duplexers generally use a cavity resonator.

  The 2 GHz band notch filter 121 needs to sufficiently suppress the 2 GHz band transmission wave and reception wave so that the 2 GHz band transmission wave and reception wave are not mixed in the 1.7 GHz band transmission / reception device. Similarly, the 1.7 GHz band notch filter 122 needs to sufficiently suppress the 1.7 GHz band transmission wave and reception wave so that the 1.7 GHz band transmission wave and reception wave do not enter the 2 GHz band transmission / reception device. It is.

  Next, a notch filter used in the antenna duplexer of the present invention and a simulation result thereof will be described with reference to FIGS. FIG. 6 is a diagram showing a configuration example of a notch filter used in the antenna duplexer of the present invention. FIG. 7 is a diagram showing a simulation result of a notch filter having FIG. 6 as a basic circuit.

  The notch filter of FIG. 6 includes an open stub 19 having three attenuation poles and short-circuit stubs 17 and 18. Specifically, in the notch filter of FIG. 6, the transmission line 12 is connected to the port 11, the transmission line 13 is connected to the transmission line 12, the transmission line 14 is connected to the transmission line 13, and the transmission line 15 is connected to the transmission line 14. Are connected, the port 16 is connected to the transmission line 15, the circuit connecting the transmission line 12 and the transmission line 13 is branched, the short-circuit stub 17 is connected, and the circuit connecting the transmission line 13 and the transmission line 14 is branched. Then, the short stub 18 is connected, and the circuit connecting the transmission line 14 and the transmission line 15 is branched to connect the open stub 19. The short-circuit stubs 17 and 18 are grounded. The notch filter can adjust the frequency band to be blocked by adjusting each stub length and transmission line length by one open stub 19, two short-circuit stubs 17 and 18 and transmission lines 12 to 15 connecting the stubs. . For example, when the transmission / reception band of the 1.7 GHz band is blocked, a notch filter that achieves a target blocking amount from 1.765 GHz to 1.880 GHz is necessary. The design frequency of the notch filter of FIG. 6 was set to 1.8225 GHz which is an intermediate between 1.765 GHz and 1.880 GHz. This is to simultaneously block the 1.7 GHz transmission band and the reception band. The transmission lines 12 to 15, the short-circuit stubs 17 and 18, and the open stub 19 all have a characteristic impedance of 50Ω and F0 = 1.8225 GHz. The transmission line 12 has a phase of 10 deg and the transmission line 13 has a phase of 127 deg. The phase of the line 14 is set to 138 deg, the phase of the transmission line 15 is set to 10 deg, the phase of the short stub 17 is set to 28 deg, the phase of the short stub 18 is set to 176 deg, and the phase of the open stub 19 is set to 107 deg.

  FIG. 7 shows a computer simulation result of a 1.7 GHz band notch filter having FIG. 6 as a basic circuit. From the simulation results in FIG. 7, it can be seen that a blocking amount of 23 dB or more was achieved from 1.765 GHz (m1) to 1.880 GHz (m2). Moreover, the maximum passage loss from 1.940 GHz (m3) to 2.150 GHz (m4) is 0.5 dB. As described above, the 1.7 GHz band notch filter can transmit and receive a 2 GHz band transmission / reception wave with low insertion loss, and can block the 1.7 GHz band by 23 dB or more. Similar characteristics can be obtained with a 2 GHz band notch filter. In addition to FIG. 6, a planar circuit constituted by a microstrip line, a circuit using a cavity resonator, a circuit using a dielectric resonator, and the like can be applied to the notch filter.

  The T distributor 111 can be configured by, for example, a three-terminal circuit of a microstrip line. For example, a circuit in which a 50Ω line is configured in a T shape. The first input / output terminal 111-1 of the T distributor 111 is connected to the antenna element, and the remaining two terminals (second input / output terminal 111-2 and third input / output terminal 111-3) are connected to the 2 GHz band notch filter 121. It is connected to a 1.7 GHz band notch filter 122. The T distributor 111 distributes the 1.7 GHz band and the 2 GHz band, but it is also necessary to prevent the 1.7 GHz band signal from being distributed to the first input / output terminal 121-1 of the 2 GHz band notch filter 121. Similarly, it is necessary to prevent a 2 GHz band signal from being distributed to the first input / output terminal 122-1 of the 1.7 GHz band notch filter 122. As a method for enabling this, the first input / output terminal 111-1 to the second input / output terminal 111-2 are viewed as being open conditions in the 1.7 GHz band, and the first input / output terminal 111-1 to the third condition. A circuit configuration in which the 2 GHz band is an open condition when the input / output terminal 111-3 is viewed is used. For example, a short-circuit point is provided at a location where the wavelength becomes a quarter wavelength of 2 GHz on the second input / output terminal 111-2 side from the branching point. Similarly, a short-circuit point is provided at a point where the wavelength is 1.7 GHz on the third input / output terminal 111-3 side from the branching point. Accordingly, the third input / output terminal 111-3 cannot be seen as a circuit from the point of branching in the 1.7 GHz band signal. The second input / output terminal 111-2 cannot be seen as a circuit from the point of branching in the 2 GHz band signal. Thereby, the branch point physically connects the 1.7 GHz band terminal and the 2 GHz band terminal, but the signals in the 1.7 GHz band and the 2 GHz band can be separated without any distribution loss. The short-circuit point may be an open stub with a quarter wavelength, or may be in contact with the ground via a chip capacitor.

  From the computer simulation result of FIG. 7, the 1.7 GHz band notch filter 122 side has a 1.7 GHz band rejection amount of 23 dB or more when viewed from the antenna element. Further, when the 2 GHz band notch filter 121 is configured with the same configuration as in FIG. 6, the 2 GHz band notch filter 121 side has a 2 GHz band rejection amount of 23 dB or more due to the symmetry of the circuit. As described above, the T duplexer 111, the 2 GHz band notch filter 121, and the 1.7 GHz band notch filter 122 can constitute a dual band antenna duplexer corresponding to the 1.7 GHz band and the 2 GHz band. The T distributor 111 is not limited to a microstrip line, and may be constituted by a coaxial cable.

  As a modification of the antenna duplexer of the present invention, the antenna duplexer may be configured by using a low-pass filter or a high-pass filter instead of the notch filter. A 1.7 GHz band notch filter corresponds to a high-pass filter that passes the 2 GHz band, and a 2 GHz band notch filter corresponds to a low-pass filter that passes the 1.7 GHz band. When these low-pass filter and high-pass filter are used, it is preferable that the frequency interval between transmission and reception is large from the viewpoint of a circuit that embodies the out-of-band attenuation characteristic.

  Hereinafter, the triple-band compatible antenna duplexer according to the second embodiment will be described with reference to FIG. FIG. 8 is a diagram illustrating the configuration of the antenna duplexer 200 according to the present embodiment.

  The antenna duplexer 200 of the present embodiment includes a T distributor 211, a 1.7 / 2 GHz band notch filter 221, a 1.5 GHz band notch filter 222, a T distributor 231, a 2 GHz band notch filter 241, .7 GHz band notch filter 242, 1.5 GHz band duplexer 251, 1.7 GHz band duplexer 252, and 2 GHz band duplexer 253.

  The first input / output terminal 211-1 of the T distributor 211 is connected to the antenna element. The second input / output terminal 211-2 of the T distributor 211 is connected to the first input / output terminal 221-1 of the 1.7 / 2 GHz band notch filter 221. The third input / output terminal 211-3 of the T distributor 211 is connected to the first input / output terminal 222-1 of the 1.5 GHz band notch filter 222. The second input / output terminal 221-2 of the 1.7 / 2 GHz band notch filter 221 is connected to the input / output terminal 251-1 of the 1.5 GHz band duplexer 251. The second input / output terminal 222-2 of the 1.5 GHz band notch filter 222 is connected to the first input / output terminal 231-1 of the T distributor 231. The second input / output terminal 231-2 of the T distributor 231 is connected to the first input / output terminal 241-1 of the 2 GHz band notch filter 241. The third input / output terminal 231-3 of the T distributor 231 is connected to the first input / output terminal 242-1 of the 1.7 GHz band notch filter 242. The second input / output terminal 241-2 of the 2 GHz band notch filter 241 is connected to the input / output terminal 252-1 of the 1.7 GHz band duplexer 252. The second input / output terminal 242-2 of the 1.7 GHz band notch filter 242 is connected to the input / output terminal 253-1 of the 2 GHz band duplexer 253. The transmission terminal 251-2 of the 1.5 GHz band duplexer 251 is connected to a 1.5 GHz band transmission circuit, and the reception terminal 251-3 is connected to a 1.5 GHz band reception circuit. The 1.7 GHz band duplexer 252 has a transmission terminal 252-2 connected to a 1.7 GHz band transmission circuit and a reception terminal 252-3 connected to a 1.7 GHz band reception circuit. The transmission terminal 253-2 of the 2 GHz band duplexer 253 is connected to a transmission circuit of 2 GHz band, and the reception terminal 253-3 is connected to a reception circuit of 2 GHz band.

  The 1.7 / 2 GHz band notch filter 221 connected to the second input / output terminal 211-2 of the T distributor 211 is connected to the third input / output terminal 211-3 of the T distributor 211 and the 1.5 GHz band notch filter 222. The signal of the frequency band (1.7 GHz band / 2 GHz band) input to the 1.7 GHz band duplexer 252 and the 2 GHz band duplexer 253 connected via the network is blocked. The 1.5 GHz band notch filter 222 connected to the third input / output terminal 211-3 of the T distributor 211 has a 1.7 / 2 GHz band notch filter 221 connected to the second input / output terminal 211-2 of the T distributor 211. The signal of the frequency band (1.5 GHz band) input into the 1.5 GHz band duplexer 251 connected via the is blocked. The 2 GHz band notch filter 241 connected to the second input / output terminal 231-2 of the T distributor 231 is connected to the third input / output terminal 231-3 of the T distributor 231 via the 1.7 GHz band notch filter 242. In addition, the signal of the frequency band (2 GHz band) input to the 2 GHz band duplexer 253 is blocked. The 1.7 GHz band notch filter 242 connected to the third input / output terminal 231-3 of the T distributor 231 is connected to the second input / output terminal 231-2 of the T distributor 231 via the 2 GHz band notch filter 221. In addition, the signal of the frequency band (1.7 GHz band) input to the 1.7 GHz band duplexer 252 is blocked.

  The 1.5 GHz band duplexer 251 has a transmission band of 1.496 GHz to 1.511 GHz and a reception band of 1.448 GHz to 1.463 GHz. The transmission / reception band isolation is about 100 dB, and the transmission loss of the transmission band and the reception band is about 0.5 dB. A configuration using a cavity resonator as a duplexer that embodies such characteristics is known.

  The 1.5 GHz band notch filter 222 is configured in the same manner as in FIG. 6, and can block a desired frequency band in the same manner as in FIG. 7. The 1.7 / 2 GHz band notch filter 221 can be realized by a configuration using two open stubs 26 and 27 and transmission lines 22, 23 and 24 as shown in FIG. 9, for example. Specifically, the notch filter of FIG. 9 has a transmission line 22 connected to a port 21, a transmission line 23 connected to the transmission line 22, a transmission line 24 connected to the transmission line 23, and a port 25 connected to the transmission line 24. The circuit connecting the transmission line 22 and the transmission line 23 is branched and the open stub 26 is connected, and the circuit connecting the transmission line 23 and the transmission line 24 is branched and the open stub 27 is connected. This is because resonance occurs in a plurality of frequency bands. The 1.7 / 2 GHz band notch filter 221 may be configured by cascading a 1.7 GHz band notch filter 221 and a 2 GHz band notch filter 241.

  FIG. 10 shows a computer simulation result of the 1.7 GHz band / 2 GHz band notch filter 221 having two open stubs shown in FIG. The circuits were open stubs 26 and 27 matched to the respective frequency bands to be blocked, and a transmission line of 1.934 GHz, which is an intermediate frequency between the 1.7 GHz band and the 2 GHz band. As for the phase of the open stub, the phase of the open stub 27 of 1.8225 GHz was 90 deg, and the phase of the open stub 26 of 2.045 GHz was 91 deg. Referring to FIG. 10, the notch filter 221 of FIG. 9 achieves a blocking amount of 28 dB or more from 1.765 GHz (m1) to 1.880 GHz (m2), and 1.940 GHz (m3) to 2.150 GHz (m4). It can be seen that the blocking amount is 25 dB or more. Further, the passage loss from 1.448 GHz (m5) to 1.511 GHz (m6) is 0.5 dB or less. In this way, a dual band notch filter can be configured by using two open stubs. In addition to this, it is also possible to configure a wide band notch filter that blocks frequencies in a wide band. For example, a notch filter may be configured with a matching circuit.

  In the above embodiment, the isolation from the 1.5 GHz band to the 1.7 GHz band is 28 dB or more, and the isolation from the 1.5 GHz band to the 2 GHz band is 28 dB or more, and the isolation from the 1.7 GHz band to the 2 GHz band is performed. Isolation is 56 dB or more. Thus, a triplexer can be configured by using a notch filter without using a band pass filter.

  In the triple-band antenna duplexer, the isolation of each frequency band depends on the amount of rejection of the notch filter. When a sufficient amount of blocking cannot be obtained, a plurality of identical frequency band notch filters may be connected in cascade.

  In the present invention, as shown in FIGS. 6, 7, 9, and 10, a notch filter that blocks a plurality of frequency bands and a notch filter having sufficient attenuation characteristics over a wide frequency band are designed. Here, the general notch filter used in Patent Document 2 is necessary and sufficient if it has the ability to block a single frequency band signal that is desired to block inflow. And 2 GHz band). The general notch filter used in Patent Document 2 is configured to have a sufficient attenuation characteristic over a wide band because it is sufficient to have a narrow band stop band for the same reason as described above. Absent. For example, since a 1.5 GHz band duplexer has a transmission band of 1.496 GHz to 1.511 GHz and a reception band of 1.448 GHz to 1.463 GHz, the first stage of a duplexer in a frequency band other than the 1.5 GHz band in the present invention. The notch filter disposed in the circuit board needs to have a sufficient blocking amount of 80 dB or more in a 63 MHz bandwidth of at least 1.448 GHz to 1.511 GHz. However, a general notch filter used in Patent Document 2 does not have such a wide band in the stop band and sufficient attenuation characteristics.

  On the other hand, the antenna duplexer of the present invention has sufficient performance (blocking amount) as an antenna duplexer used in a plurality of frequency bands when used in combination with a duplexer configured in the preceding stage of the transmission circuit and the reception circuit. The relationship between the stop band and the rejection rate of the notch filter is sufficiently adjusted. In other words, an extreme value solution satisfying this configuration is searched for for the notch filter. In the present invention, an unprecedented small and lightweight multiband antenna duplexer can be realized by optimizing the notch filter as described above.

  Hereinafter, the quad-band compatible antenna duplexer according to the third embodiment will be described with reference to FIG. FIG. 11 is a diagram illustrating the configuration of the antenna duplexer 300 according to the present embodiment.

  The antenna duplexer 300 of this embodiment includes three T distributors 311, 331, 332, six notch filters 321, 322, 341, 342, 343, 344, and four duplexers 351, 352, 353, 354. Prepare.

  In the present embodiment, two circuit configurations used in the antenna duplexer 100 of the first embodiment are used to configure a circuit that couples quad bands (800 MHz band, 1.5 GHz band, 1.7 GHz band, 2 GHz band). Specifically, the first input / output terminal 311-1 of the T distributor 311 is an antenna element, the second input / output terminal 311-2 is the first input / output terminal 321-1 of the notch filter 321, and the third input / output. The terminal 311-3 is connected to the first input / output terminal 322-1 of the notch filter 322. The first input / output terminal 331-1 (332-1) of the T distributor 331 (332) is connected to the second input / output terminal 321-2 (322-2) of the notch filter 321 (322). The second input / output terminal 331-2 (332-2) of the T distributor 331 (332) is connected to the first input / output terminal 341-1 (343-1) of the notch filter 341 (343) and the T distributor 331 (332). ) Third input / output terminal 331-3 (332-3) is connected to the first input / output terminal 342-1 (344-1) of the notch filter 342 (344). Among the notch filters, the second input / output terminals 341-2, 342-2, 343-2, and 344-2 of the notch filters 341, 342, 343, and 344 that belong to the end most when viewed from the antenna element are duplexers 351, 352, 353 and 354 are connected to input / output terminals (351-1, 352-1, 353-1, 354-1). The transmission terminals 351-2, 352-2, 353-2, and 354-2 of the duplexers 351, 352, 353, and 354 are transmission circuits, and the reception terminals 351-3, 352-3, 353-3, and 354-3 are receptions. Connected with the circuit.

  The notch filter connected to the second (3) input / output terminal of an arbitrary T distributor (any of 311, 331, 332) passes through the notch filter at the third (2) input / output terminal of the T distributor. Block the frequency band signal input to all connected duplexers.

  Each frequency band notch filter can be configured in the same manner as in FIG. 6 and blocks a desired frequency band. The 800 / 1.5 GHz notch filter 322 for blocking the 800 MHz band and the 1.5 GHz band can be composed of a plurality of open stubs as in FIG. Also, a 1.7 / 2 GHz band notch filter 321 that blocks the 1.7 GHz band and the 2 GHz band can be configured in the same manner as in FIG.

  Each frequency band isolation of a circuit that couples quad bands is determined by the number of notch filters. For example, in FIG. 10, the isolation between the 1.5 GHz band and the 2 GHz band is the amount of rejection in the 1.5 GHz band of at least the 800 GHz band and the 1.5 GHz band notch filter. Similarly, the isolation between 800 MHz and 2 GHz band is at least 800 MHz band and 800 MHz band rejection of 1.5 GHz band notch filters.

  The antenna duplexer of the present invention is not limited to two, three, and four frequency bands like the antenna duplexer in the first to third embodiments, and can be configured to increase the corresponding frequency bands indefinitely. . Therefore, after describing the conditions that must be satisfied in common regardless of how many frequency bands the antenna duplexer of the present invention is used, with reference to FIG. 12, the decaband (10 The antenna duplexer 400 corresponding to the type of frequency band will be described. FIG. 12 is a diagram illustrating a configuration of the antenna duplexer 400 according to the present embodiment.

In the antenna duplexer of the present invention, a distributor that distributes signals and a notch filter that suppresses a desired frequency band of the distributed signals are alternately connected in cascade. P and an integer of 1 or more, Q, shall be the integer of 2 or more of R. It is necessary to include first to Pth distributors (T distributors), first to Qth notch filters, and first to Rth duplexers. As described in the first embodiment, the distributor (T distributor) includes a first input / output terminal, a second input / output terminal, and a third input / output terminal, and the second input / output terminal is viewed from the first input / output terminal. It is necessary that the frequency band passing through the third input / output terminal is an open condition, and the frequency band passing through the second input / output terminal when viewed from the first input / output terminal to the third input / output terminal is an open condition. is there. The notch filter includes a first input / output terminal and a second input / output terminal. The duplexer includes an input / output terminal, a transmission terminal, and a reception terminal.

Of the dividers (T dividers), the T divider connected to the antenna has a first input / output terminal as the antenna element, a second input / output terminal as the first input / output terminal of the first notch filter, The three input / output terminals are connected to the first input / output terminal of the second notch filter. Among the distributors (T distributors) , the p-th distributor (p is an integer of 2 or more and P or less ) which is a distributor (T distributor) other than the distributor (T distributor) connected to the antenna element. 1 input and output terminals and a second output terminal of the (p-1) Bruno notch filter, a second input and output terminals and the first output terminal of the (2p-1) Bruno notch filter, the third output terminal the first It is connected to the first output terminal of the 2p Bruno notch filter. Among the first to Q-th notch filters, the second input / output terminals of the R notch filters that belong to the end as viewed from the antenna element are connected to the input / output terminals of the first to R-th duplexers. The transmission terminals of the first to R-th duplexers are connected to the transmission circuit, and the reception terminals are connected to the reception circuit. The notch filter connected to the second (3) input / output terminal of an arbitrary distributor (T distributor) is connected to the third (2) input / output terminal of the distributor (T distributor) via the notch filter. The present invention is characterized by blocking signals in a frequency band that are input to all the duplexers. The antenna duplexer of the present invention is configured to satisfy all the above requirements regardless of the number of corresponding frequency bands.

  Hereinafter, the antenna duplexer 400 of this embodiment that supports Dica band will be briefly described. The antenna duplexer 400 of the present embodiment includes nine T distributors 411, 431, 432, 451, 452, 471 to 474, and 18 notch filters 421, 422, 441 to 444, 461 to 464, 481 to 488. And 10 duplexers 490-499. Therefore, in the above description, P = 9, Q = 18, and R = 10.

  For the T divider 411 connected to the antenna, the first input / output terminal is the antenna element, the second input / output terminal is the first input / output terminal of the notch filter 421, and the third input / output terminal is the first input / output terminal of the notch filter 422. 1 Connected to input / output terminal. The first input / output terminals of the remaining eight T distributors (431, 432, 451, 452, 471 to 474) are the second input / output terminals of the notch filters (421, 422, 441, 442, 461 to 464), and The second input / output terminal is a first input / output terminal of a notch filter (441, 443, 461, 463, 481, 483, 485, 487), and the third input / output terminal is a notch filter (442, 444, 462, 464, 482, 484, 486, 488). The second input / output terminals of notch filters 443, 444, 481 to 488 belonging to the end as viewed from the antenna element are connected to the input / output terminals of duplexers 490 to 499. Duplexers 490 to 499 have transmission terminals connected to a transmission circuit and reception terminals connected to a reception circuit. A notch filter connected to the second (3) input / output terminal of an arbitrary T distributor is connected to the third (2) input / output terminal of the T distributor via a notch filter or a notch filter and a T distributor. The signal of the frequency band input into all the duplexers connected via the is blocked. For example, the notch filter 422 connected to the third input / output terminal of the T distributor 411 is input to all the duplexers 491 to 498 connected to the second input / output terminal of the T distributor 411 via the notch filter. It is configured to block signals in the bands (first to eighth frequency bands).

  In the first to fourth embodiments, the notch filter is inserted into the output of the power amplifier and the band-pass filter is inserted into the output of the low noise receiving amplifier, so that the isolation of each frequency band can be further increased. Hereinafter, the antenna duplexer 500 according to the fifth embodiment in which a notch filter and a band pass filter are further added to the triple-band compatible antenna duplexer 300 according to the third embodiment will be described with reference to FIG. FIG. 13 is a diagram illustrating a configuration of the antenna duplexer 500 according to the present embodiment. In this embodiment, notch filters 561, 562, 563 and amplifiers 581, 582, 583 are inserted into the transmission system of 1.5 GHz band, 1.7 GHz band, and 2 GHz band in the antenna duplexer 300 of the third embodiment. Band-pass filters 591, 592, 593 and amplifiers 571, 572, 573 are inserted in the 5 GHz band, 1.7 GHz band, and 2 GHz band reception systems.

  Notch filters 561 to 563 inserted in the transmission system suppress the frequency components of the reception band. For example, the notch filter 561 inserted in a 1.5 GHz band transmission system suppresses frequency components from 1.448 GHz to 1.463 GHz in the 1.5 GHz band reception band. Band pass filters 591 to 593 inserted into the reception system pass the frequency components of the reception band. For example, the band pass filter 591 inserted in the 1.5 GHz band reception system passes frequency components from 1.448 GHz to 1.463 GHz in the 1.5 GHz band reception band. This is effective when sufficient isolation cannot be obtained between transmission and reception of the duplexer of each frequency band. That is, the notch filter inserted into the transmission band reduces the leakage of the transmission wave into the reception band, and the band-pass filter inserted into the reception band reduces the interference from the transmission wave in the triple band transmission band.

  In the first to fifth embodiments, the distributors were divided into two, and the circuit configuration was a tournament configuration. In the sixth embodiment, an antenna duplexer in which the circuit configuration is a star configuration using a distributor that divides into three will be described. Hereinafter, the antenna duplexer of the sixth embodiment will be described with reference to FIG. FIG. 14 is a diagram illustrating the configuration of the antenna duplexer 600 according to the present embodiment.

  As shown in FIG. 14, the antenna duplexer 600 of the present embodiment can be configured as a modified version of the fifth embodiment, for example. The antenna duplexer 600 of this embodiment includes a distributor 611 as a substitute for the T distributors 511 and 531. The distributor 611 includes a first input / output terminal 611-1, a second input / output terminal 611-2, a third input / output terminal 611-3, and a fourth input / output terminal 611-4. In addition, the antenna duplexer 600 of this embodiment includes a 2 GHz band open stub 6211, a 1.7 GHz band open stub 6212, a 2 GHz band open stub 6411, a 1.5 GHz band open stub 6412, and a 1.7 GHz band open stub. 6421 and a 1.5 GHz band open stub 6422. In addition, the antenna duplexer 600 of the present embodiment includes a 1.7 / 2 GHz band notch filter 521, a 1.5 GHz band notch filter 522, a 2 GHz band notch filter 541, and 1 .7 GHz band notch filter 542 is not provided. About each other structure, since it is the same as the antenna sharing device 500 of Example 5, description is abbreviate | omitted.

  The first input / output terminal 611-1 of the distributor 611 is connected to the antenna. The second input / output terminal 611-2 is connected to the input / output terminal 551-1 of the 1.5 GHz band duplexer 551, and a 2 GHz band open stub 6211 and a 1.7 GHz band open stub 6212 are arranged in the middle of the line. Connected. The third input / output terminal 611-3 is connected to the input / output terminal 552-1 of the 1.7 GHz band duplexer 552, and a 2 GHz band open stub 6411 and a 1.5 GHz band open stub 6412 are arranged in the middle of the line. Connected. The fourth input / output terminal 611-4 is connected to the input / output terminal 553-1 of the 2 GHz band duplexer 553, and a 1.7 GHz band open stub 6421 and a 1.5 GHz band open stub 6422 are arranged in the middle of the line. Connected.

  In the divider 611, the frequency band passing through the third and fourth input / output terminals 611-3 and 4 as viewed from the first input / output terminal 611-1 to the second input / output terminal 611-2 becomes an open condition, and the first input The frequency band passing through the second and fourth input / output terminals 611-2 and 4 as viewed from the output terminal 611-1 to the third input / output terminal 611-3 is an open condition, and the first input / output terminal 611-1 to the fourth input terminal. The frequency band passing through the second and third input / output terminals 611-2 and 3 when viewed from the input / output terminal 611-4 is an open condition.

  The signal input from the antenna element is divided into three by the distributor 611 and output from the second input / output terminal 611-2, the third input / output terminal 611-3, and the fourth input / output terminal 611-4, respectively. The distributed signal is filtered by a notch filter of another frequency band that filters a desired frequency band. For example, a signal input to a 1.5 GHz band duplexer 551 is filtered by a 2 GHz band open stub 6211 corresponding to a 2 GHz band notch filter and a 1.7 GHz band open stub 6212 corresponding to a 1.7 GHz band notch filter, and is distributed. A signal in the 1.5 GHz band is extracted from the signal distributed in 611. The signal input to the 1.7 GHz band duplexer 552 is filtered by a 2 GHz band open stub 6411 corresponding to a 2 GHz band notch filter and a 1.5 GHz band open stub 6412 corresponding to a 1.5 GHz band notch filter. A 1.7 GHz band signal is extracted from the distributed signal. The signal input to the 2 GHz band duplexer 553 is filtered by a 1.7 GHz band open stub 6421 corresponding to a 1.7 GHz band notch filter and a 1.5 GHz band open stub 6422 corresponding to a 1.5 GHz band notch filter, and is distributed. A signal in the 2 GHz band is extracted from the signal distributed in 611.

  Hereinafter, with reference to FIG. 15, an example in which the antenna duplexer 600 of this embodiment is configured by a planar circuit will be described. FIG. 15 is a diagram illustrating an example in which the antenna duplexer 600 of the present embodiment is configured by a planar circuit.

  As shown in FIG. 15, the distributor 611 includes four transmission lines 6111, 6112, 6113 and 6114. The open stubs 6211, 6212, 6411, 6412, 6421, and 6422 in each frequency band are each configured by a transmission line. Specifically, the transmission line 6111 is connected to the first port 61, the transmission lines 6112, 6113, 6114 are branched and connected to the transmission line 6111, the transmission line 65 is connected to the transmission line 6112, and the transmission line 65 Is connected to the second port 62. A transmission line 66 is connected to the transmission line 6113, and a third port 63 is connected to the transmission line 66. The transmission line 67 is connected to the transmission line 6114, and the fourth port 64 is connected to the transmission line 67. A circuit connecting the transmission line 6112 and the transmission line 65 is branched to connect the open stub 6211, a circuit connecting the transmission line 65 and the second port 62 is branched to connect the open stub 6212, and the transmission line 6113 is transmitted. The circuit connecting the line 66 is branched to connect the open stub 6411, the circuit connecting the transmission line 66 and the third port 63 is branched to connect the open stub 6412, and the transmission line 6114 and the transmission line 67 are connected. The circuit is branched to connect the open stub 6421, and the circuit connecting the transmission line 67 and the fourth port 64 is branched to connect the open stub 6422.

  In the distributor 611, assuming that the input impedance of the first port 61 is 50Ω and each open stub input impedance is 50Ω, the transmission line 6111 immediately adjacent to the first port 61 is impedance-converted from a characteristic impedance of 50Ω to 50 / 3Ω. Thereafter, the transmission lines 6112, 6113, and 6114 are impedance-converted from 50 / 3Ω to 50Ω, respectively. At this time, the characteristic impedance of the transmission lines 6111, 6112, 6113, 6114 is 28.8Ω. The distributor 611 is designed at 1.958 GHz which is the center frequency of three bands. In order to connect the 1.5 GHz band duplexer 551 to the second port 62, a 2 GHz band open stub 6211 and a 1.7 GHz band open stub 6212 are used as in FIG. Since the higher the frequency, the shorter the wavelength, the 2 GHz band open stub 6211 is arranged closer to the antenna than the 1.7 GHz band open stub 6212. In order to connect the 1.7 GHz band duplexer 552 to the third port 63, the 2 GHz band open stub 6411 and the 1.5 GHz band open stub 6412 are used as in FIG. The 2 GHz band open stub 6411 is disposed closer to the antenna than the 1.5 GHz band open stub 6412. In order to connect the 2 GHz band duplexer 553 to the fourth port 64, a 1.7 GHz band open stub 6421 and a 1.5 GHz band open stub 6422 are used as in FIG. The transmission line can be created by a microstrip line. By giving specific substrate constants, the line width and line length can be determined.

  In the circuit configuration example of FIG. 15, the transmission line 6111, 6112, 6113, 6114 has a characteristic impedance of 28.8Ω, a phase of 90 deg, a frequency F0 = 1958 MHz, and the transmission lines 65, 66, 67 have a characteristic impedance of 50Ω, The phase is 10 deg and the frequency F0 = 1958 MHz. The characteristic impedance of the open stub 6211 is 50Ω, phase 90 deg, frequency F0 = 2040 MHz, the characteristic impedance of the open stub 6212 is 50Ω, phase 143 deg, frequency F0 = 1823 MHz, the characteristic impedance of the open stub 6411 is 50Ω, phase The characteristic impedance of the open stub 6412 is 50Ω, the phase is 94 deg, the frequency F0 = 1480 MHz, the characteristic impedance of the open stub 6421 is 50Ω, the phase is 36.5 deg, and the frequency is F0 = 1823 MHz. The characteristic impedance of the stub 6422 is 50Ω, the phase is 88 deg, and the frequency is F0 = 1480 MHz.

  Next, circuit characteristics in the planar circuit configuration example of FIG. 15 will be described with reference to FIG. FIG. 16 is a diagram illustrating a linear simulation result by a microwave circuit simulator for an example in which the antenna duplexer 600 of the present embodiment is configured by a planar circuit.

  In FIG. 16, the graph indicated by the triangle symbol is S11 (reflection characteristic of the first port), the graph indicated by the square symbol is S21 (passage characteristic from the first port to the second port), and the graph indicated by the rhombus symbol is S31. (Passage characteristic from the first port to the third port), a graph indicated by a butterfly quadrilateral symbol is S41 (passage characteristic from the first port to the fourth port). Here, the passing frequency of the 1.5 GHz band is from 1448 MHz to 1511 MHz. The passing frequency of the 1.7 GHz band is 1765 MHz to 1880 MHz. The passing frequency of the 2 GHz band is 1940 MHz to 2150 MHz. As shown in FIG. 16, the insertion loss at the pass frequency is in the range of 1.951 dB to 0.6828 dB. Thus, it can be seen that the 3-band duplexer using the 3-distributor having a star configuration can operate as a circuit. Whether the distributor is divided into two and the tournament configuration is as in the first embodiment, or the distributor is divided into three as in the sixth embodiment and the star configuration is determined depending on the number of frequency bands to be demultiplexed and the distribution. Depends on the characteristics required of the vessel. As the number of frequency bands to be separated increases, the star configuration has fewer stages than the tournament configuration, so that the circuit can be configured more compactly and there is an advantage that a low loss can be achieved.

  The antenna duplexer of the present invention is not limited to three frequency bands like the antenna duplexer in the sixth embodiment, and can be configured to increase the corresponding frequency bands indefinitely in theory. Hereinafter, conditions that must be satisfied in common when a star configuration is made using a distributor that distributes three parts as in the sixth embodiment will be described.

In the antenna duplexer of the present invention, a distributor that distributes signals and a notch filter that suppresses a desired frequency band of the distributed signals are alternately connected in cascade. P and an integer of 1 or more, Q, shall be the integer of 2 or more of R.

  The antenna duplexer of the present invention needs to include first to Pth distributors, first to Qth notch filters, and first to Rth duplexers. As described in the sixth embodiment, the distributor includes the first to fourth input / output terminals, and the frequency band passing through the third and fourth input / output terminals when viewed from the first input / output terminal to the second input / output terminal. Is the open condition, the frequency band passing through the second and fourth input / output terminals from the first input / output terminal to the third input / output terminal is the open condition, and the first input / output terminal is viewed from the fourth input / output terminal. 2. It is necessary that the frequency band passing through the third input / output terminal is configured to be an open condition. The notch filter includes a first input / output terminal and a second input / output terminal. The duplexer includes an input / output terminal, a transmission terminal, and a reception terminal.

Distributor connected to the antenna out of the distributor (Example 6, the distributor 611) is its first input-output terminal is the antenna element, the second, third, fourth output terminal the first, second 2. Connected to each first input / output terminal of the third notch filter. Among distributor, other than distributor connected to the antenna element distributor first output terminal of the (first p distributor) of the second input terminal of the (p-1) Bruno notch filter, second, 3, the fourth output terminal the first (3p-2), the (3p-1), is connected to the first output terminal of the 3p Bruno notch filter.

  Among the first to Q-th notch filters, the second input / output terminals of the R notch filters that belong to the end as viewed from the antenna element are connected to the input / output terminals of the first to R-th duplexers. The transmission terminals of the first to R-th duplexers are connected to the transmission circuit, and the reception terminals are connected to the reception circuit. The notch filter connected to the second input / output terminal of any distributor has a frequency band input to all the duplexers connected to the third and fourth input / output terminals of the distributor via the notch filter. Block the signal. The notch filter connected to the third input / output terminal of any distributor has a frequency band input to all duplexers connected to the second and fourth input / output terminals of the distributor via the notch filter. Block the signal. The notch filter connected to the fourth input / output terminal of any distributor has a frequency band input to all duplexers connected to the second and third input / output terminals of the distributor via the notch filter. Block the signal.

  The antenna duplexer 600 according to the sixth embodiment is an example of the antenna duplexer according to the present invention configured as P = 1, Q = 3, and R = 3.

<Modification 1>
Hereinafter, with reference to FIG. 17, a description will be given of an antenna duplexer 600 a of Modification 1 which is a modification of Embodiment 6. FIG. 17 is a diagram illustrating a configuration of an antenna duplexer according to the first modification. The antenna duplexer 600a of the present modification has a configuration using LPF, BPF, and HPF as an alternative to the notch filter using the open stub of the sixth embodiment. As shown in FIG. 17, the antenna duplexer 600a according to the present modification includes a 1.5 GHz band LPF 621 and a 1.7 GHz band BPF 641 instead of the open stubs 6211, 6212, 6411, 6412, 6421, and 6422 of the sixth embodiment. 2 GHz band HPF642. The 1.5 GHz band LPF 621 includes a first input / output terminal 621-1 and a second input / output terminal 621-2. The 1.7 GHz band BPF 641 includes a first input / output terminal 641-1 and a second input / output terminal 641-2. The 2 GHz band HPF 642 includes a first input / output terminal 642-1 and a second input / output terminal 642-2.

  The first input / output terminal 611-1 of the distributor 611 is connected to the antenna. The second input / output terminal 611-2 is connected to the first input / output terminal 621-1 of the 1.5 GHz band LPF 621, and the third input / output terminal 611-3 is the first input / output terminal 641 of the 1.7 GHz band BPF 641. -1 and the fourth input / output terminal 611-4 is connected to the first input / output terminal 642-1 of the 2 GHz band HPF 642. The second input / output terminal 621-2 of the 1.5 GHz band LPF 621 is connected to the input / output terminal 551-1 of the 1.5 GHz band duplexer 551. The second input / output terminal 641-2 of the 1.7 GHz band BPF 641 is connected to the input / output terminal 552-1 of the 1.7 GHz band duplexer 552. The second input / output terminal 642-2 of the 2 GHz band HPF 642 is connected to the input / output terminal 553-1 of the 2 GHz band duplexer 553.

  A signal input to the 1.5 GHz band duplexer 551 is filtered by a 1.5 GHz band LPF 621 that is an LPF that removes signals of 1.7 GHz band and 2 GHz band from a signal input to the distributor 611. Similarly, the signal input to the 1.7 GHz band duplexer 552 is filtered from the signal input to the distributor 611 by the 1.7 GHz band BPF 641, which is a BPF that filters the 1.5 GHz band and 2 GHz band signals. The signal input to the 2 GHz band duplexer 553 is filtered by the 2 GHz band HPF 642 which is an HPF that filters the 1.5 GHz band and 1.7 GHz band signals from the signal input to the distributor 611. A 3-band duplexer can be configured with a 3-distributor in a star configuration without using a tournament configuration in 3 bands as in this modification.

Claims (8)

An antenna duplexer in which a distributor for distributing a signal and a notch filter for suppressing a desired frequency band of the distributed signal are alternately connected in cascade,
P is an integer of 1 or more, Q and R are integers of 2 or more ,
A first input / output terminal, a second input / output terminal, and a third input / output terminal are provided. When the second input / output terminal is viewed from the first input / output terminal, the frequency band passing through the third input / output terminal becomes an open condition, and the first input / output The first to P-th distributors having a frequency band passing through the second input / output terminal when viewed from the terminal to the second input / output terminal are open conditions, the first input / output terminal and the second input / output terminal. A first to R-duplexer comprising a Q-th notch filter, an input / output terminal, a transmission terminal, and a reception terminal;
The first input / output terminal of the first distributor is an antenna element, the second input / output terminal of the first distributor is the first input / output terminal of the first notch filter, and the third input / output of the first distributor. The terminal is connected to the first input / output terminal of the second notch filter,
When P is an integer of 2 or more, p is an integer of 2 or more and P or less,
The said first input terminal of the first p distributor and the second output terminal of the (p-1) Bruno notch filter, a second input terminal of the first p distributor Part (2p-1) Bruno notch filter 1 and output terminal, a third input terminal of the first p divider is connected to the first output terminal of the 2p Bruno notch filter,
Of the first to Q-th notch filters, the second input / output terminals of the R notch filters belonging to the end as viewed from the antenna element are connected to the input / output terminals of the first to R-th duplexers,
The transmission terminals of the first to R-th duplexers are connected to a transmission circuit, and the reception terminals are connected to a reception circuit.
The notch filter connected to the second input / output terminal of the arbitrary distributor blocks the frequency band signal input to all duplexers connected to the third input / output terminal of the distributor via the notch filter. And
The notch filter connected to the third input / output terminal of the arbitrary distributor blocks frequency band signals input to all duplexers connected to the second input / output terminal of the distributor via the notch filter. Antenna duplexer to do.   The antenna duplexer according to claim 1, wherein the P is 1, the Q is 2, and the R is 2.   The antenna duplexer according to claim 1, wherein the P is 2, the Q is 4, and the R is 3.   The antenna duplexer according to claim 1, wherein the P is 3, the Q is 6, and the R is 4. An antenna duplexer in which a distributor for distributing a signal and a notch filter for suppressing a desired frequency band of the distributed signal are alternately connected in cascade,
P is an integer of 1 or more, Q and R are integers of 2 or more ,
A frequency that includes a first input / output terminal, a second input / output terminal, a third input / output terminal, and a fourth input / output terminal, and passes through the third and fourth input / output terminals when viewed from the first input / output terminal. The band is an open condition, the frequency band passing through the second and fourth input / output terminals from the first input / output terminal to the third input / output terminal is the open condition, and the first input / output terminal to the fourth input / output terminal. A first to Q-th notch filter including first to P-th distributors in which a frequency band passing through the second and third input / output terminals is an open condition; a first input / output terminal and a second input / output terminal; An antenna duplexer comprising first to R-duplexers comprising an input / output terminal, a transmission terminal, and a reception terminal,
The first input / output terminal of the first distributor is an antenna element, the second input / output terminal of the first distributor is the first input / output terminal of the first notch filter, and the third input / output of the first distributor. The terminal is connected to the first input / output terminal of the second notch filter, the fourth input / output terminal of the first distributor is connected to the first input / output terminal of the third notch filter,
When P is an integer of 2 or more, p is an integer of 2 or more and P or less,
The said first input terminal of the first p distributor and the second output terminal of the (p-1) Bruno notch filter, a second input terminal of the first p distributor Part (3p-2) Bruno notch filter 1 and output terminal, the third input terminal of the p distributor first input and output terminals of the first (3p-1) Bruno notch filter, a fourth input terminal of the first p distributor Chapter 3p Bruno notch filter Connected to the first input / output terminal of
Of the first to Q-th notch filters, the second input / output terminals of the R notch filters belonging to the end as viewed from the antenna element are connected to the input / output terminals of the first to R-th duplexers,
The transmission terminals of the first to R-th duplexers are connected to a transmission circuit, and the reception terminals are connected to a reception circuit.
The notch filter connected to the second input / output terminal of the arbitrary distributor is a frequency band inputted to all duplexers connected to the third and fourth input / output terminals of the distributor via the notch filter. Block the signal of
The notch filter connected to the third input / output terminal of the arbitrary distributor is a frequency band inputted to all duplexers connected to the second and fourth input / output terminals of the distributor via the notch filter. Block the signal of
The notch filter connected to the fourth input / output terminal of the arbitrary distributor is a frequency band input to all duplexers connected to the second and third input / output terminals of the distributor via the notch filter. An antenna duplexer that blocks the signal.   The antenna duplexer according to claim 5, wherein the P is 1, the Q is 3, and the R is 3. The antenna duplexer according to any one of claims 1 to 6,
An antenna duplexer comprising a band-pass filter that allows a reception band signal to pass between a reception terminal of the duplexer and a reception circuit. The antenna duplexer according to any one of claims 1 to 6,
An antenna duplexer comprising a notch filter for blocking a reception band signal passing through a reception terminal of the duplexer between a transmission terminal and a transmission circuit of the duplexer.

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