JP2003152588A - Multi-band antenna switching circuit and multi-band antenna switch laminate module composite part, and communication equipment using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multi-band antenna switching circuit and laminate parts capable of suppressing higher harmonic yield, and realizing miniaturization and low power consumption. SOLUTION: This multi-band antenna switch circuit is provided with a first diplexer Dip1 having a first transmission terminal and a second reception terminal and a first common terminal, a second diplexer Dip2 having a second transmission terminal and a first reception terminal and a second common terminal, and a switching circuit SW having a first transmission/reception terminal and a second transmission/reception terminal and an antenna terminal, where either the first transmission/reception terminal or the second transmission/reception terminal is switched and connected to the antenna terminal. In this case, the first common terminal is connected to the first transmission/ reception terminal, and the second common terminal is connected to the second transmission/reception terminal, and a notch filter VNF is connected between the antenna terminal and the switching circuit. Also, it is possible to provide multi-band antenna switch laminate module composite parts constituting the multi-band antenna- switching circuit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-band antenna switch circuit, a multi-band antenna switch laminated module composite component, and a communication device using the same, and more particularly, a single antenna sharing two or more different frequency signals. The present invention relates to a wireless communication system that transmits and receives.

[0002]

2. Description of the Related Art EGSM (Extended Global), which is popular mainly in Europe, is used as a portable radio communication system.
l System for Mobile Commu
communications) system and DCS (Digital)
l Cellular System method, PCS (Personal Communicat) popular in the United States
Ion Service system, PDC (Personal Digital Cell) adopted in Japan
There are various systems such as the (ular) system, but due to the rapid spread of mobile phones in recent years, the system users cannot be covered by the frequency band allocated to each system, especially in the major metropolitan areas of developed countries. , There are problems such as difficulty in connection or disconnection during a call. Therefore, it has been proposed to allow users to use a plurality of systems so as to substantially increase available frequencies, further expand service areas, and effectively utilize communication infrastructure of each system.

When the user wants to use a plurality of systems, it is necessary to have as many portable communication devices corresponding to each system as necessary, or to have a small and lightweight portable communication device capable of communicating with a plurality of systems. is there. In the latter case, to enable multiple systems with one mobile communication device,
The mobile communication device may be configured using the components of each system, but in the signal transmission system, for example, a filter that passes a transmission signal of a desired transmission frequency, a high-frequency switch that switches the transmission / reception circuit, and a transmission / reception signal are transmitted / received. In an antenna or a signal receiving system, a high frequency circuit component such as a filter that allows a desired frequency of a received signal that has passed through the high frequency switch is required for each system. For this reason, the portable communication device becomes expensive, and its volume and weight increase, which is unsuitable for portable use. Therefore, small and lightweight high-frequency circuit components compatible with multiple systems have become necessary. For example, a dual band compatible high frequency switch module used in a portable communication device compatible with two systems of EGSM and DCS is disclosed in JP-A-11-22.
No. 5088, Japanese Patent Laid-Open No. 2001-185902, and US Pat. No. 5,815,804.

The former Japanese Patent Laid-Open No. 11-225 shown in FIG.
In the switch circuit of the prior art in the 088 publication, a switch circuit SW1 that switches between the EGSM transmission terminal (Tx) and the EGSM reception terminal (Rx), the DCS transmission terminal (Tx), and the DCS reception terminal (Rx).
And a diplexer Dip connected to the switch circuits SW2 and SW1 and SW2. SW1 and SW2
For each of them, a switch circuit using the PIN diode switch shown in FIG. 20 is used. Therefore, EGSM,
A DCS-compatible high-frequency switch module requires a total of four PIN diodes, which hinders miniaturization.

On the other hand, of the latter, Japanese Patent Laid-Open No. 2001-18
In No. 5902, as shown in FIG. 21, EGSM transmission terminal and DC
Sip diplexer Dip1 for demultiplexing with S transmission terminal and E
Switch circuit connected to the diplexer Dip2 and Dip1 and Dip2 on the receiving side that demultiplexes the GSM receiving terminal and the DCS receiving terminal
Have SW. For the SW, one FET switch such as a GaAs switch is used to cover a wide band from the EGSM band to the DCS band. Therefore, compared to a switch circuit that uses a PIN diode switch, it can be made smaller and power consumption can be reduced.

On the other hand, in US Pat. No. 5,815,804, a diplexer Dip1 for demultiplexing an EGSM receiving terminal and a DCS transmitting terminal, a diplexer Dip2 for demultiplexing an EGSM transmitting terminal and a DCS receiving terminal, and Dip1 and Dip2 are connected. The switch circuit SW includes a FET switch such as a GaAs switch as in the above example.

[0007]

[Problems to be Solved by the Invention]
In the conventional technique of 1-185902, since the switch circuit SW is connected to the diplexer Dip1 on the transmission side in the EGSM transmission mode, there is a problem that a signal in the DCS band input from the DCS transmission terminal is also passed. In the EGSM transmission mode, the power amplifier on the DCS side is set not to operate, but due to oscillation by the 2nd harmonic of the EGSM transmission signal and crosstalk with the amplifier on the EGSM side, the power amplifier on the DCS side will Also produces a slight signal. This phenomenon is particularly remarkable in the case of a dual power amplifier in which two power amplifiers of EGSM and DCS are combined in one package, and a signal of about -15 dBm may be output from the power amplifier on the DCS side.

That is, in the EGSM transmission mode, a 1.8 GHz band signal corresponding to twice the frequency of the EGSM transmission band is input to the DCS transmission terminal, and the diplexer Dip1 and the switch SW pass the 1.8 GHz band signal as it is. Therefore, the double harmonic distortion of EGSM transmission is radiated from the antenna, which becomes a problem. The second harmonic generation amount radiated from this antenna is preferably -36 dBm or less, which is a problem that cannot be avoided by the conventional technique of FIG.

A GaAs switch is used in the switch circuit together with Japanese Patent Laid-Open No. 2001-185902 and US Pat. No. 5,815,804. GaAs switches also have the problem that harmonic distortion is more likely to occur when compared to circuits using PIN diodes. Especially in EGSM transmission, the maximum power of +36 dBm
It may be applied to a GaAs switch, and in order to suppress the amount of double harmonic generation to -36 dBm or less, it is necessary to set the amount of double harmonic generation of the EGSM transmission signal generated by the GaAs switch itself to -72 dBc or less. . However, it is currently difficult to obtain such a GaAs switch that generates a small amount of harmonics. This is because it is possible to easily reduce the amount of harmonics generated in the GaAs switch by increasing the power supply voltage, but it is adopted as a component used in mobile phones because the increase in power supply voltage corresponds to the increase in battery power supply voltage. This is because it cannot be done.

Further, in the case of a circuit in which transmission / reception signals of a plurality of frequencies are directly switched by a GaAs switch without using a diplexer, there is a problem that it is weak against electrostatic breakdown. Therefore, it is necessary to install a circuit for electrostatic surge protection between the antenna and the GaAs switch. For example, conventional electrostatic surge countermeasures are disclosed in Japanese Patent Application Laid-Open Nos. 2001-44883 and 2001-186047. However, these are for circuits using PIN diodes, and these electrostatic surge countermeasure circuits were not suitable for use on the antenna top.

In view of the above problems, the present invention is a multi-band antenna switch circuit, a multi-band antenna switch laminated module composite part, which is small in size, has low power consumption, suppresses the generation of harmonics, and is strong against electrostatic breakdown, and An object is to provide a communication device using these.

[0012]

In order to solve the problems of a conventional switch circuit using a PIN diode, such as miniaturization and low power consumption, the present invention provides a FET switch such as a GaAs switch and a diplexer. This is a multi-band antenna switch circuit that has a basic configuration using two, and transmits between the switch circuit and the antenna in order to suppress the amount of harmonic generation that is a concern when using FET switches such as GaAs switches. The gist of the present invention is to insert a notch filter, for example, as a filter for attenuating twice or three times the frequency of the signal. Further, the present invention is based on GaAs
It is a multi-band antenna switch circuit that has a basic configuration using one FET switch such as a switch and two diplexers. To prevent electrostatic breakdown, which is a problem when using a FET switch such as a GaAs switch, a switch circuit is used. The gist of the present invention is to insert a filter for absorbing a surge voltage due to electrostatic discharge to the ground between the antenna and, for example, a high-pass filter.

That is, according to the present invention, there is provided a first diplexer having a first transmission terminal, a second reception terminal and a first common terminal, a second transmission terminal, a first reception terminal and a second common terminal. A second diplexer having a terminal, a first transmission / reception terminal, a second transmission / reception terminal, and an antenna terminal, and one of the first transmission / reception terminal and the second transmission / reception terminal is the antenna terminal. And a switch circuit that is switch-connected to the first common terminal connected to the first transmission / reception terminal and the second common terminal connected to the second transmission / reception terminal. The multi-band antenna switch circuit is provided between the antenna and a filter for attenuating twice or three times the frequency of a transmission signal input to the first transmission terminal or the second transmission terminal.

Further, according to the present invention, there is provided a first diplexer having a first transmitting terminal, a second receiving terminal and a first common terminal, a second transmitting terminal, a first receiving terminal and a second common terminal. A second diplexer having a first transmission / reception terminal, a second transmission / reception terminal, and an antenna terminal, and one of the first transmission / reception terminal and the second transmission / reception terminal is connected to the antenna terminal. A switch circuit that is switchably connected, the first common terminal is connected to the first transmission / reception terminal, the second common terminal is connected to the second transmission / reception terminal, and the switch circuit and the antenna It is a multi-band antenna switch circuit in which a notch filter is provided between and.

In the above invention, it is desirable to adopt the following configuration. The notch filter has an inductor, a diode, a capacitor, a resistor, and a power supply terminal,
The resonance frequency is variable by the voltage applied to the power supply terminal. A reverse voltage terminal for applying a reverse voltage to the diode is provided in the notch filter. The first
And a second low-pass filter at the second transmission terminal. The switch circuit shall be composed of GaAs semiconductor. A first inductor having an input terminal and an output terminal, connected between the input terminal and the ground, a first capacitor connected between the input terminal and the output terminal, and connected to the output terminal And a high-pass filter including the second inductor and the second capacitor connected to the ground and the second inductor is provided at least between the notch filter and the antenna. Inserting a parallel resonant circuit including a third inductor and a third capacitor between the second inductor of the high pass filter and the output terminal.

According to the present invention, there is provided a first diplexer having a first transmission terminal, a second reception terminal and a first common terminal, and a second transmission terminal, a first reception terminal and a second common terminal. It has a 2nd diplexer which has, a 1st transmission / reception terminal, a 2nd transmission / reception terminal, and an antenna terminal, and any one of the 1st transmission / reception terminal and the 2nd transmission / reception terminal switches to the said antenna terminal. With a switch circuit connected,
The first common terminal is connected to the first transmission / reception terminal, the second common terminal is connected to the second transmission / reception terminal, and a surge voltage due to electrostatic discharge is applied between the switch circuit and the antenna. It is a multi-band antenna switch circuit having a filter for absorbing to the ground.

Further, according to the present invention, there is provided a first diplexer having a first transmission terminal, a second reception terminal and a first common terminal, a second transmission terminal, a first reception terminal and a second common terminal. A second diplexer having a first transmission / reception terminal, a second transmission / reception terminal, and an antenna terminal, and one of the first transmission / reception terminal and the second transmission / reception terminal is connected to the antenna terminal. A switch circuit that is switchably connected, the first common terminal is connected to the first transmission / reception terminal, the second common terminal is connected to the second transmission / reception terminal, and the switch circuit and the antenna A first inductor connected between the input terminal and the switch circuit, and an input terminal connected to the antenna, and an output terminal connected to the switch circuit, and the input terminal and the output. Between terminals A multi-band antenna switch circuit having a connected first capacitance, a second inductor connected to the output terminal, and a high-pass filter including the second inductor and a second capacitance connected to the ground. . Here, the second of the high-pass filter
A parallel resonance circuit composed of a third inductor and a third capacitor may be inserted between the inductor and the output terminal.

According to the present invention, a part of a transmission line and a capacitor forming the above-mentioned multi-band antenna switch circuit is built in a laminated board, and a switch element, a resistor, a capacitor and a part of the multi-band antenna switch circuit are formed. It is a multi-band antenna switch laminated module composite component in which chip components such as inductors are mounted on a laminated substrate.

Furthermore, the present invention is a communication device using the above-mentioned multi-band antenna switch circuit or multi-band antenna switch laminated module composite component.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Since the multi-band antenna switch circuit of the present invention is configured as described above, the first diplexer demultiplexes signals having different frequency bands into the first transmitting terminal and the second receiving terminal. Then, the second diplexer demultiplexes signals in different frequency bands to the second transmission terminal and the first reception terminal. Further, the switch circuit switches the connection between the antenna terminal and the first diplexer or between the antenna terminal and the second diplexer. Therefore, when the first transmission terminal and the antenna terminal are connected, the second transmission terminal is cut off by the switch circuit, so that the output from the power amplifier in the OFF state, which was a problem in the conventional technique, is output. Harmonic distortion that does not pass to the antenna terminal. Similarly, when the second transmission terminal and the antenna terminal are connected, the first transmission terminal is cut off by the switch circuit, and thus is output from the power amplifier in the OFF state, which is a problem in the conventional technique. Harmonic distortion is not passed to the antenna terminal.

In the present invention, the first low-pass filter connected to the first transmission terminal is a signal having a fundamental frequency with respect to the transmission signal output from the power amplifier input to the first transmission terminal. Only high frequency harmonic distortion. Similarly, the second low-pass filter connected to the second transmission terminal passes only the signal of the fundamental frequency with respect to the transmission signal output from the power amplifier input to the second transmission terminal, Reduces harmonic distortion. A low-pass filter or a notch filter connected between the switch circuit and the antenna is adjusted so as to have an attenuation pole at a frequency twice or three times the frequency of the transmission signal. Therefore, by connecting these filters, it is possible to effectively reduce the second-order or third-order harmonic distortion generated in the switch circuit.

The notch filter of the present invention comprises an inductor, a diode switch, a capacitor, a resistor, and a power supply terminal, and the resonance frequency of the notch filter can be changed by the voltage applied to the power supply terminal. Therefore, when the first transmission terminal is connected to the antenna terminal, the attenuation pole of the notch filter is set to the frequency of the double or triple harmonic of the first transmission signal, and the second transmission terminal is set to the antenna. When it is connected to the terminal, the harmonic generation amount in both bands can be reduced at the same time by setting the frequency of the double or triple harmonic of the second transmission signal. Further, the harmonic distortion occurs in the notch filter itself when no voltage is applied to the diode switch forming the notch filter. In order to avoid this, it is effective to provide a reverse voltage terminal for applying a reverse voltage to the diode switch.

Since the switch circuit used in the present invention needs to pass low-frequency and high-frequency signals input to and output from the diplexer with low loss, a GaAs FET switch having a wide pass band is used. However, Ga
As FET switches have the demerit that they are weak against electrostatic breakdown as compared with PIN diodes. This can be solved by providing a filter for absorbing the electrostatic surge voltage to the ground between the switch circuit and the antenna. According to a more specific high-pass filter, the surge voltage due to electrostatic discharge is released to the ground side by the first inductor and the first capacitance, and the series resonance circuit including the second inductor and the second capacitance connected to the ground is used. It is possible to effectively absorb the electrostatic surge in the resonance frequency band to the ground and to match in a wide band from 900MHz band to 1.8GHz band.

Further, since the diplexer forming the multi-band antenna switch circuit and a part of the transmission line and the capacitance of the switch circuit are built in and integrated with the laminated board, the wiring between the diplexer and the switch circuit is also provided on the surface or inside the laminated board. Are formed on the substrate, the loss due to wiring is reduced, and the matching adjustment between the two is facilitated. On the other hand, chip components such as switch elements, resistors, capacitors, and inductors that form part of the multi-band antenna switch circuit are mounted on a laminated substrate to obtain a compact and inexpensive multi-band antenna switch laminated module composite component. . Further, a communication device using these multi-band antenna switch circuits or multi-band antenna switch laminated module composite parts has a small size and low power consumption specifications. From the above, the antenna switch circuit, the multi-band antenna switch laminated module composite component, and the communication device of the present invention can suppress the harmonic generation amount in the power amplifier and the harmonic generation amount in the switch circuit, and reduce the static electricity of the GaAs FET switch. It is possible to achieve protection against electric breakdown, downsizing, cost reduction, and power consumption reduction.

Embodiments of a multi-band antenna switch circuit, a multi-band antenna switch laminated module composite component, and a communication device according to the present invention will be described below with reference to the drawings. First, FIG. 2 shows an example of a multi-band antenna switch circuit according to the present invention, EG
The block diagram of the antenna switch circuit corresponding to SM and DCS is shown. The first diplexer Dip1 is an EGSM transmission signal (880MHz-
915MHz) and the DCS reception signal (1805MHz to 1880MHz) are demultiplexed and combined. The second diplexer Dip2 is an EGSM received signal (925M
(Hz to 960MHz) and DCS transmission signal (1710MHz to 1785MHz) are demultiplexed and combined. The switch circuit SW is connected to Dip1 and Dip2, and is connected between the antenna terminal ANT and Dip1 or the ANT terminal.
Switch the connection between Dip2. In this case, the switch circuit needs to pass with a low loss signal EGSM and DCS bands, wide passband SPDT (S ingle P ole D ual T hrow)
A GaAs FET switch or the like called is used. Therefore, ANT terminal and Dip1 are connected, and EGSM transmission terminal and A
When the NT terminal is connected, the DCS transmission terminal is shut off by SW. In the EGSM transmission mode, the power amplifier on the DCS side is set not to operate, but due to oscillation by the 2nd harmonic of the EGSM transmission signal and crosstalk with the amplifier on the EGSM side, the power amplifier on the DCS side will Also produces a slight signal. In other words, the second harmonic of the EGSM transmission signal generated by the power amplifier on the EGSM side (1760MHz to 1830MHz)
However, due to crosstalk between the EGSM and DCS power amplifiers, D
It is input from the CS transmission pin and passes through Dip2. However, the SW blocks the connection between the ANT terminal and Dip2, so it cannot pass through to the ANT terminal side. On the other hand, in the conventional technique of FIG. 21, since the DCS transmission terminal and the ANT terminal are connected in the EGSM transmission mode, the 2nd harmonic of the EGSM transmission signal is AN.
There was a problem because it passed to the T terminal. From the above, the circuit configuration of the present invention makes it possible to reduce the amount of double harmonic generation of the EGSM transmission signal in the EGSM transmission mode.

(Embodiment 1) FIG. 1 is a block diagram of an antenna switch circuit compatible with EGSM and DCS, which is an embodiment of the multi-band antenna switch circuit of the present invention. In this embodiment, in addition to the circuit of the above embodiment, low-pass filter LPF1 between Dip1 and EGSM transmission terminals, low-pass filter LPF2 between Dip2 and DCS transmission terminals, and variable notch filter VNF between ANT and SW, respectively. Has been inserted. LPF1 is EGSM
In order to suppress high-order harmonic distortion included in the transmitted signal, EG
A filter having a characteristic of passing only the SM transmission signal and attenuating a frequency twice or more that of the EGSM transmission signal is used. Similarly, the LPF2 suppresses high-order harmonic distortion included in the DCS transmission signal, and therefore a filter having a characteristic of passing only the DCS transmission signal and attenuating a frequency twice or more that of the DCS transmission signal is used. Therefore, since the harmonic distortion generated in the power amplifier is reduced by LPF1 and LPF2, the amount of harmonic generation radiated from the antenna can be reduced. In addition, the variable notch filter VNF is a notch filter that has an attenuation pole at twice or three times the frequency of the EGSM transmission signal in the EGSM transmission mode in order to reduce the amount of harmonics generated in the GaAs FET switch. Yes, in the DCS transmission mode, a notch filter having a characteristic having an attenuation pole at a frequency twice or three times that of the DCS transmission signal is desirable,
In this embodiment, the variable notch filter in which the resonance frequency changes in each of the EGSM and DCS modes is adopted.
Therefore, the harmonic distortion generated in the GaAs FET switch is
It can be reduced by F. It is needless to say that the present invention is not limited to the variable notch filter VNF as in the embodiment, and a normal notch filter NF may be used. Furthermore, it is not limited to notch filters,
The point is that a filter that attenuates a frequency that is twice or three times that of various transmission signals may be used.

FIG. 8 shows an example of a concrete equivalent circuit of this embodiment. The diplexer Dip1 is composed of transmission lines or inductors L7 to L9 and capacitors C8 to C11. L8 and C8
It is desirable to form a series resonance circuit and design it so that it has a resonance frequency in the DCS reception band. 1.8G in this embodiment
The attenuation pole was set to Hz. It is desirable that L9 and C10 form a series resonant circuit and that the resonant frequency be in the EGSM transmission band. In this embodiment, the attenuation pole is set to 0.9 GHz. This circuit makes it possible to demultiplex the EGSM transmission signal and the DCS reception signal. The diplexer Dip2 is composed of transmission lines or inductors L4 to L6 and capacitors C4 to C7. It is desirable that L5 and C4 form a series resonance circuit and have a resonance frequency in the DCS transmission band.
In this embodiment, the attenuation pole is set to 1.8 GHz. It is desirable that L6 and C6 form a series resonance circuit and that the resonance frequency be in the EGSM reception band. In this embodiment, the attenuation pole is set to 0.9 GHz. This circuit allows DCS transmission signals and EGSM
The received signal can be demultiplexed and combined.

The low pass filter LPF1 is composed of a transmission line or inductor L11 and capacitors C15 to C17.
At this time, L11 and C15 form a parallel resonance circuit, and the resonance frequency thereof is preferably set to be twice or three times the EGSM transmission frequency. In this embodiment, the frequency is tripled to 2.7 GHz. With this circuit, it is possible to reduce the amount of triple harmonic generation of EGSM transmission generated by the power amplifier. Low pass filter LPF2
Is a transmission line or inductor L10 and capacitors C12 to C14
It is composed of At this time, L10 and C12 form a parallel resonance circuit, and the resonance frequency thereof is preferably set to be twice or three times the DCS transmission frequency. In this embodiment, it is doubled 3.
Set to 6GHz. With this circuit, it is possible to reduce the amount of double harmonic generation of DCS transmission generated by the power amplifier.

The variable notch filter VNF is composed of a transmission line or inductor L1, a choke coil L2, capacitors C1 to C3, a diode switch D and a resistor R. L1, D
And C3 form a series resonance circuit, the resonance frequency of which changes depending on the ON / OFF state of the diode D. Normally, the diode is close to a short circuit in the ON state and 0.1 to 1.0p in the OFF state.
Has a capacitance value of F. Therefore, a series resonance circuit of L1 and C3 is formed in the ON state, and a series resonance circuit of L1 and C3 and the capacitance value of the diode is formed in the OFF state. VN used in this example
The characteristics of F are shown in FIG. When the diode is ON, it has an attenuation pole at a frequency three times that of the EGSM transmission signal (about 2.7 GHz), and when the diode is OFF, it has twice the frequency of the DCS transmission signal (about 2.7 GHz).
A characteristic with an attenuation pole at 3.6 GHz is obtained. The resonance frequency when the diode is ON and the resonance frequency when the diode is OFF can be arbitrarily adjusted by the combination of L1 and C3. In order for the diode D to be in the ON state, it is necessary to apply a voltage of about 0.7 V or more to the diode to flow a direct current, and the choke coil L2 is necessary to flow this direct current. Further, L2 is preferably 20 nH to 100 nH so that the impedance becomes large for signals in the EGSM and DCS bands. In this example, 27 nH was used. Also, the resistance R
Limits the value of the current flowing through the diode D. In this example, 1 kΩ was used.

The choke coil L2 is directly below the antenna,
Moreover, since it is connected to the ground, even if an electrostatic surge is applied from the outside, L2 makes it easier for the surge to escape to the ground. For this reason, the antenna switch circuit also has a function of protecting components that are weak against electrostatic damage, such as the SW circuit and the SAW filters, power amplifiers, and low-noise amplifiers connected thereafter. Alternatively, an antenna switch circuit using a GaAs switch can be realized by providing a circuit in which an inductor is inserted as shown in FIGS. 18 (a) and 18 (b) described below to absorb a surge voltage due to electrostatic discharge to the ground. Is effective in. However, (b) requires a large number of inductors and capacitors, which hinders size reduction and cost reduction, and also causes deterioration of insertion loss. In (a), an inductor is added to a part of the demultiplexer. To protect the GaAs switch from electrostatic surge, it is necessary to set the inductor that falls to the ground to 5nH or less, but 5nH on the antenna top. If the following inductors are connected, it will be difficult to achieve matching in a wide band from 900MHz band to 1.8GHz band. In order to solve these problems, it is more desirable to use a high pass filter circuit described later.

The switch circuit SW includes Dip1, Dip2, and VN.
Connected to F, when VC1 is High, VNF-Dip1 is connected and VNF-Dip2 is cut off. Conversely, when VC2 is High
VNF and Dip2 are connected, and VNF and Dip1 are blocked. C
1, C2, C18 and C19 are DC cut capacitors required for switching the switch circuit SW and turning ON / OFF the diode D.

Table 1 shows the relationship between the operation mode and the power supply voltage in this embodiment. The high power supply voltage level in Table 1 is + 1V to +5.
V and Low should be -0.5V to + 0.5V. In EGSM transmission mode, VC1 and VC3 are High, VC2 is Low, SW is ANT and D
Connect between ip1 and ANT and Dip2 will be open. Also, the resonance frequency of the notch filter VNF turns on the diode D.
The frequency is about 2.7 GHz, which is three times the frequency of the EGSM transmission signal.
become. In DCS transmission mode, VC2 is High and VC1, VC3
Goes low, SW connects between ANT and Dip2, and ANT and Dip
1 is open. The resonance frequency of the notch filter VNF is about 3.6 GHz, which is twice the frequency of the DCS transmission signal because the diode D is in the OFF state. In EGSM reception mode, VC2 is ON, VC1 and VC3 are Low, SW connects ANT and Dip2, and ANT and Dip1 are open. The resonance frequency of the notch filter VNF is about 3.6 GHz because the diode D is in the OFF state. In DCS reception mode, VC1 is ON, VC2 and VC3 are Low, SW connects ANT and Dip1, and ANT and Dip2 are open. The resonance frequency of the notch filter VNF is about 3.6 GHz because the diode D is in the OFF state.

[0033]

[Table 1]

Next, Table 2 shows the measurement results of the harmonic suppression effect according to the present embodiment. The measurement is made in the case of not having a notch filter as shown in FIG. 2 and in the case of the present invention in which a notch filter or the like is provided as in the embodiment of FIG. 1, the attenuation amount (dB) of the second and third harmonics (2f, 3f) ) Was measured.
As is clear from this result, the suppression effect of 20 dB or more was confirmed by the present invention. According to the above-described embodiment, the antenna switch circuit of the present invention can suppress the amount of harmonic generation in the power amplifier, suppress the amount of harmonic generation in the switch circuit, and protect against electrostatic damage. Is clear.

[0035]

[Table 2]

(Embodiment 2) Next, FIG. 10 shows an equivalent circuit diagram of an antenna switch circuit compatible with EGSM and DCS, which is another embodiment of the present invention. In this embodiment, the variable notch filter VNF shown in FIG. 8 of the first embodiment is modified.
The VNF of this embodiment is composed of a transmission line or inductor L1, choke coils L2 and L3, capacitors C1 to C3, a diode switch D and a resistor R. L1, D and C3 form a series resonance circuit, and the resonance frequency thereof changes depending on the ON / OFF state of the diode D as in the first embodiment. The VNF shown in this embodiment is characterized in that a reverse voltage can be applied to the diode D.

It is generally known that when a high-power high-frequency signal is applied to a nonlinear device such as a diode, harmonic distortion occurs. O especially for PIN diodes
It is remarkable in the FF state. The reason for this is clear from the VI characteristics of the diode shown in FIG. 9, and in the ON state, the diode is driven at an operating point with relatively good linearity due to the voltage Vc of the control power supply, so there is However, since it has a linear response, the amount of generated harmonics is small. On the other hand, in the OFF state, the operating point is near V = 0, and a non-linear response is provided even to voltage fluctuations due to high frequency signals. For this reason, the amount of harmonic generation increases. The relationship between the operation mode and the power supply voltage in this embodiment is the same as in Table 1.
The difference from the first embodiment is that VC2 is Hi in DCS transmission mode.
This means that the reverse voltage can be applied to the diode D because gh and VC3 become Low. When a reverse voltage is applied to the diode, as shown in FIG. 9, it produces a linear response to the voltage fluctuation due to the high frequency signal, so that the amount of harmonic generation in the notch filter can be reduced. VC2 is High and VC in DCS transmission mode
1, VC3 becomes Low, SW connects between ANT and Dip2, AN
T and Dip1 are open. At the resonance frequency of the notch filter VNF, the diode D is in the OFF state, but a reverse voltage is applied. The choke coil L3 is designed to have a high impedance of 20nH for signals in the EGSM and DCS bands.
100nH is desirable. In this example, 27 nH was used. Further, the resistor R limits the value of the current flowing through the diode D. In this example, 1 kΩ was used. Furthermore, inductor L2 is ANT
It is also possible to realize an electrostatic breakdown protection function by connecting it directly below. According to the above embodiment, a multi-band antenna switch circuit capable of reducing the amount of harmonic generation in the OFF state of the diode D, which is a problem of the first embodiment, can be obtained.

(Embodiment 3) FIG. 3 is a block diagram of another embodiment of the present invention, a triple band antenna switch circuit compatible with EGSM, DCS and PCS. This embodiment is the first embodiment.
This is a switch circuit with a PCS receiving terminal added.
The present invention relates to an antenna switch circuit having a basic configuration using one FET switch such as a GaAs switch and two diplexers. As long as this basic configuration is provided,
Even if a plurality of transmission / reception systems are added, it can be said that the multi-band antenna switch circuit of the present invention. The same applies to the following examples. Now, in this embodiment using the GaAs FET switch called SP3T (S ingle P ole 3 T hrow) as the switch. Further DCS
By making the transmission terminal and PCS transmission terminal common, the circuit can be simplified. In this case, DCS transmission (1710MHz ~
1785MHz) and PCS transmission (1850MHz ~ 1910MHz) are relatively close to each other, so the power amplifier can be shared. The other detailed description is omitted because it is the same as the above embodiment, but according to this embodiment, a triple band antenna switch circuit compatible with EGSM, DCS, and PCS can be obtained.

(Embodiment 4) FIG. 4 is a block diagram of a quad band antenna switch circuit compatible with EGSM, DAMPS, DCS and PCS, which is another embodiment of the present invention. In this embodiment, the switch circuit of the fourth embodiment is connected to the diplexer Dip3 and a DAMPS receiving terminal is added. Furthermore, by making the EGSM transmission terminal and the DAMPS transmission terminal common, the circuit can be simplified. In this case, since the EGSM transmission (880MHz to 915MHz) and the DAMPS transmission (824MHz to 849MHz) are relatively close to each other, the power amplifier can be shared. As described above, according to this embodiment, EGSM, DAMPS, DCS,
A quad band antenna switch circuit compatible with PCS can be obtained.

(Embodiment 5) FIG. 12 is a block diagram of another embodiment of the present invention, a quad band antenna switch circuit compatible with EGSM, DCS, PCS and W-CDMA. G, as the switch of the present example is called SP4T (S ingle P ole 4 T hrow)
An aAs FET switch was used. Furthermore, it is a circuit in which a duplexer Dup is connected after the W-CDMA transceiver terminal. In this case, the duplexer Dup is the W-CDMA band (192
(0MHz to 2170MHz) can be combined by demultiplexing the transmitted and received signals to switch between W-CDMA transmission and reception, and can be used for different systems of TDMA and CDMA. As described above, according to this embodiment
Quad-band antenna switch circuit compatible with EGSM, DCS, PCS and W-CDMA can be obtained.

(Embodiment 6) Generally, a GaAs switch is more expensive than a diode switch, and the SP3T type used in Embodiments 3 and 4 and the SP used in Embodiment 5 are used.
The 4T type GaAs switch is the SPDT type GaAs switch used in the first and second embodiments.
It is more expensive than a GaAs switch and is not suitable as a component used in a mobile phone terminal. As one improvement of that point, FIG. 5 shows another embodiment of the present invention, EGSM, DAMPS, DC.
The block diagram of the quad band antenna switch circuit corresponding to S and PCS is shown. In the present embodiment, in addition to the circuit of the first embodiment, a circuit in which a phase demultiplexer PS2 is connected to Dip1 and a phase demultiplexer PS1 is connected to Dip2. Since the GaAs switch used in this embodiment is SPDT, low-cost parts can be realized as compared with the case of using SP3T and SP4T. FIG. 11 shows a concrete equivalent circuit of this embodiment. Dip1, Dip2, SW, LP
Since F1, LPF2 and VNF are the same as those described in the first embodiment, the description thereof is omitted here.

The phase demultiplexer PS1 is composed of transmission lines L12, L13, DAMPS.
It is composed of a SAW filter SAW1 for reception and a SAW filter SAW2 for reception of EGSM. The transmission line L13 is a λ / 4 resonator in which the length of the transmission line is adjusted so as to resonate at the DAMPS reception frequency (869 MHz to 894 MHz). The transmission line L12 is a λ / 4 resonator in which the length of the transmission line is adjusted so as to resonate at the EGSM reception frequency (925 MHz to 960 MHz). The λ / 4 resonator has the characteristic that the impedance changes greatly depending on the termination condition. It has a 50Ω impedance for a 50Ω termination, an open impedance for a short termination, and a short impedance for an open termination. On the other hand, the SAW filter has a characteristic of 5 in the pass band.
It has an impedance close to a short-circuit at frequencies near 0Ω and the pass band. Therefore, in the DAMPS reception band, the impedance of the EGSM reception terminal seen from the diplexer Dip2 is open, and the impedance of the DAMPS reception terminal is 5
It becomes 0Ω and the DAMPS reception signal is demultiplexed to the DAMPS reception terminal side. Conversely, in the EGSM reception band, the diplexer Dip2
The impedance of the DAMPS receiving terminal seen from is open, E
The impedance of the GSM receiving terminal becomes 50Ω, and the EGSM receiving signal is demultiplexed to the EGSM receiving terminal side. With the above operation PS1
Can split the DAMPS received signal and the EGSM received signal.

The phase demultiplexer PS2 comprises transmission lines L14, L15, a DCS receiving SAW filter SAW3, and a PCS receiving SAW filter SAW4. The transmission line L15 is a λ / 4 resonator in which the length of the transmission line is adjusted so as to resonate at the DCS reception frequency (1805 MHz to 1880 MHz). The transmission line L14 is a λ / 4 resonator in which the length of the transmission line is adjusted so as to resonate at the PCS reception frequency (1930 MHz to 1990 MHz). The λ / 4 resonator has the characteristic that the impedance changes greatly depending on the termination condition. It has a 50Ω impedance for a 50Ω termination, an open impedance for a short termination, and a short impedance for an open termination. On the other hand, the characteristics of the SAW filter have an impedance of 50Ω in the pass band and an impedance close to a short circuit at frequencies near the pass band. Therefore, in the DCS reception band, the impedance of the PCS reception terminal seen from the diplexer Dip1 is open, and the impedance of the DCS reception terminal is 50.
It becomes Ω, and the DCS reception signal is demultiplexed to the DCS reception terminal side.
Conversely, in the PCS reception band, the impedance of the DCS reception terminal seen from the diplexer Dip1 is open, the impedance of the PCS reception terminal is 50Ω, and the PCS reception signal is branched to the PCS reception terminal side. With the above operation, the PS2 can demultiplex the DCS reception signal and the PCS reception signal.

Further, the circuit can be simplified by making the EGSM transmission terminal and the DAMPS transmission terminal common. In this case, EGSM transmission (880MHz to 915MHz) and DAMPS transmission (824MHz)
(MHz ~ 849MHz) and a relatively close frequency, the power amplifier can be shared. Similarly, DCS transmission terminal and PCS
By using a common transmission terminal, the circuit can be simplified. In this case, DCS transmission (1710MHz ~ 1785MHz) and PCS
Since the frequency of transmission (1850MHz to 1910MHz) is relatively close, the power amplifier can be shared. According to the above embodiment, the EG switch can be used by using only one SPDT GaAs switch.
A quad-band antenna switch circuit compatible with SM, DAMPS, DCS, and PCS can be obtained, which enables downsizing and cost reduction.

Next, a high-pass filter for electrostatic surge countermeasures will be described. FIG. 13 is an equivalent circuit diagram showing the embodiment. In FIG. 13, the inductor L1 is an input terminal
Connected between P1 and ground, the capacitance C1 is inserted between the input terminal P1 and the output terminal P2, and the series resonant circuit consisting of the inductor L2 and the capacitance C2 is connected between the output terminal P2 and the ground. There is. In this case, by appropriately selecting the values of L1 and C1, a high-pass filter is constructed so that the electrostatic surge escapes to the ground and the high frequency signal is transmitted with low loss. Here, L1 is preferably 50 nH or less, and C1 is preferably 10 pF or less. Further, the series resonance circuit composed of L2 and C2 sets the values of L and C so that the resonance frequency is set between 100 MHz and 500 MHz. In this case, C2 is preferably 10 pF or more and L2 is preferably 50 nH or less. As a result, the electrostatic surge in the resonance frequency band, which is a problem due to electrostatic breakdown, can be absorbed in the ground, and the electrostatic surge countermeasure can be taken more efficiently.

FIG. 14 shows another embodiment of the high-pass filter circuit for electrostatic surge countermeasures. Inductor in FIG.
The roles of L1, L2 and capacitors C1, C2 are the same as those shown in FIG. 13, but a parallel resonant circuit composed of capacitor C3 and inductor L3 is inserted between capacitor C1 and output terminal P2. Is different. This parallel resonant circuit has a function of removing a harmonic noise signal transmitted from the antenna by setting an attenuation pole at a frequency N times that of the transmission signal.
Further, by adjusting the values of C3 and L3, the matching of the entire electrostatic surge circuit can be adjusted, which is more effective.

The destruction due to an electrostatic surge that may occur in an actual mobile terminal is supposed to be caused when the human body comes into contact with the antenna of the mobile terminal while being charged. The Human Body Model is generally used as a method for experimentally reproducing this situation. The surge waveform from the human body is DC to 300MHz from this model.
It is known that the frequency components up to are dominant.
Therefore, the electrostatic surge countermeasure circuit of FIG. 13 of the present invention and FIG.
Attenuation characteristics from DC to 2 GHz were measured for the circuits shown in (a) and (b). FIG. 16 shows attenuation characteristics, and FIG. 17 shows reflection characteristics. As a characteristic comparison, the signals to be passed are assumed to be in the 900MHz band and 1800MHz band indicated by the triangles in the figure, and
As shown in 7, the reflection characteristics VSWR in each band
It was set to 1.5 or less. According to the attenuation characteristics of Fig. 16, the amount of attenuation in the frequency band of 300MHz or less, which is a problem due to electrostatic breakdown, is 5dB in the electrostatic surge countermeasure circuit of Fig. 18 (a) (b).
In contrast to the following, in the electrostatic surge countermeasure circuit of FIG.
It is 30 dB or more, and this electrostatic surge countermeasure circuit is 25
The amount of attenuation (above 17 times) (electrostatic surge elimination effect) is secured.

(Embodiment 7) FIG. 15 shows an embodiment of a triple band antenna switch circuit equipped with a high-pass filter for electrostatic surge countermeasures. In this example, the SP3T switch switches the EGSM transmission signal and DCS reception signal to the demultiplexer Dip1 among the signals input and output from the antenna terminal, switches the DCS / PCS transmission signal and the EGSM reception signal to the demultiplexer Dip2, and The received signal is switched to SAW for PCS reception. The low-pass filter LPF1 plays a role of attenuating the Nth harmonic distortion included in the transmission signal input from the EGSM TX terminal, and the LPF2 has the Nth harmonic distortion included in the transmission signal input from the DCS / PCS TX terminal. Plays the role of attenuating. S
AW filters SAW1, SAW2, and SAW3 are EGSM received signals,
It plays the role of removing noise outside the reception band included in the DCS reception signal and PCS reception signal. The duplexer Dip1 is LPF1 and SAW2
, And the duplexer Dip2 is connected to LPF2 and SAW1.

Electrostatic surge countermeasure circuit is antenna terminal ANT and S
Inserted between P3T switches to absorb the electrostatic surge input from the antenna to the ground. The parallel resonance circuit consisting of inductor L3 and capacitor C3 shown in the dotted line frame is an option, but when this parallel resonance circuit is provided, the attenuation pole is set at a frequency twice that of DCS / PCS Tx (34
20MHz ~ 3820MHz) by adjusting the 4 of EGSM transmission
Since the double frequency (3520 MHz to 3660 MHz) can be attenuated at the same time, the DCS / PCS transmission double attenuation amount and the EGSM transmission four times attenuation amount can be simultaneously attenuated. Further, since the parallel resonant circuits L3 and C3 also have a function as a matching circuit, they are useful for matching adjustment of the entire antenna switch. This electrostatic surge protection circuit is not only for the antenna top, but also between Dip and LPF, or Dip and S if necessary.
You may insert as needed between AW. Further, although the notch filter is omitted in this example, it goes without saying that the notch filter and the like described above may be provided in combination. As described above, circuits such as the SP3T switch, the SAW filter for reception, the power amplifier connected to the transmission terminal, and the low noise amplifier connected to the reception terminal can be efficiently protected from electrostatic surges.

(Embodiment 8) A part of the transmission line and the capacitor constituting the diplexer, the low-pass filter and the variable notch filter according to the present invention can be built in the dielectric laminated substrate, and SPDT, SP3T, SP used as the switch circuit can be used.
GaAs FET switch element such as 4T, and resistor,
By mounting chip components such as capacitors and choke coils on the dielectric laminated substrate, a compact and inexpensive multi-band antenna switch laminated module composite component can be obtained. FIG. 7 shows a perspective view of the antenna switch laminated module composite component shown by the equivalent circuit of FIG. Inside the stack, diplexers Dip1, Dip2, low pass filter LPF
1, LPF2 and variable notch filter The transmission lines and capacitors that make up VNF are divided into multiple layers and printed,
The size and weight can be reduced. Further, in this embodiment, the laminated substrate uses a ceramic dielectric material (LTCC) that can be fired at a low temperature of 950 ° C. or less, and the ceramic green sheet before firing has a sheet thickness so as to easily form a transmission line and a capacitance. The thing of 40-200 micrometers was used. A plurality of the ceramic green sheets are laminated, cut into individual pieces, printed with side electrodes, and then fired at 950 ° C. to obtain a laminated body of an antenna switch laminated module composite component. Further, by mounting a GaAs FET switch, a chip resistor, a chip capacitor and a choke coil on the obtained laminated body, the antenna switch laminated module composite component shown by the equivalent circuit of FIG. 8 can be obtained.

(Other Embodiments) In the above embodiments, EGS is used.
The multi-band antenna switch circuit compatible with M, DCS, DAMPS, PCS and W-CDMA has been described.
PDC800 band (810 to 960MHz), GPS band (1575.42MHz), PHS
Band (1895 to 1920MHz), Bluetooth band (2400 to 2484MHz)
The same effect can be expected in the case of CDMA2000, which is expected to become popular in the United States, and TD-SCDMA, which is expected to become popular in China. Therefore, according to the present invention, it is possible to obtain a multi-mode multi-band antenna switch circuit such as a dual band, a 3-band, a 4-band, a 5-band, etc. in which the amount of harmonics is suppressed, and a circuit using a conventional PIN diode. In comparison, downsizing and low power consumption are possible.

[0052]

According to the present invention, an FE such as a GaAs switch is
A T-switch and two diplexers are used, a low-pass filter is connected to the transmission terminal of the diplexer, and a notch filter is used between the antenna terminal and the switch to achieve GaAs.
It is possible to suppress the amount of harmonic generation that is a concern when using FET switches such as switches. Further, if an electrostatic surge countermeasure circuit is used, the electrostatic surge from the antenna terminal is released to the ground, and the electrostatic surge is absorbed in a wide range of frequency bands, so that the electrostatic breakdown can be more completely prevented.
Further, since the transmission line and part of the capacitance of the diplexer and the switch circuit are built in and integrated with the laminated substrate, the wiring between the diplexer and the switch circuit is also formed on the surface or inside of the laminated substrate to reduce the loss due to the wiring, In addition, matching adjustment between the two becomes easy. Furthermore, since chip components such as switch elements, resistors, capacitors and inductors are mounted on the laminated substrate, the laminated module composite component becomes smaller and cheaper. As described above, a communication device using these multi-band antenna switch circuits or multi-band antenna switch laminated module composite parts can be downsized and have low power consumption as compared with a circuit using a conventional PIN diode. .

[Brief description of drawings]

FIG. 1 is a block diagram of an EGSM / DCS compatible antenna switch circuit showing an embodiment of the present invention.

FIG. 2 is a block diagram showing an example of an EGSM / DCS compatible antenna switch circuit.

FIG. 3 shows another embodiment of the present invention, in which EGSM, DCS, PCS
It is a block diagram of a corresponding antenna switch circuit.

FIG. 4 shows another embodiment of the present invention, in which EGSM, DAMPS, D
It is a block diagram of the antenna switch circuit corresponding to CS and PCS.

FIG. 5 shows another embodiment of the present invention, in which EGSM, DAMPS, D
It is a block diagram of the antenna switch circuit corresponding to CS and PCS.

FIG. 6 is a diagram showing characteristics of a variable notch filter used in the present invention.

FIG. 7 is a perspective view of an EGSM / DCS compatible antenna switch laminated module composite component of the present invention.

FIG. 8 is an equivalent circuit diagram of the EGSM / DCS compatible antenna switch circuit shown in FIG. 1 according to the present invention.

FIG. 9 is a diagram showing operating points of a PIN diode.

FIG. 10 is an equivalent circuit diagram of an EGSM / DCS compatible antenna switch circuit using a reverse notch type variable notch filter according to another embodiment of the present invention.

11] EGSM, DAMPS, D shown in FIG. 5 according to the present invention
It is an equivalent circuit diagram of a CS, PCS compatible antenna switch circuit.

FIG. 12 shows another embodiment according to the present invention, EGSM, W-CDM
It is a block diagram of an antenna switch circuit corresponding to A, DCS, and PCS.

FIG. 13 is an equivalent circuit diagram of an embodiment of a high-pass filter for preventing electrostatic surge according to the present invention.

FIG. 14 is an equivalent circuit diagram of another high-pass filter for preventing electrostatic surges according to the present invention.

FIG. 15 is a block diagram of an antenna switch circuit using a high-pass filter for electrostatic surge prevention according to another embodiment of the present invention.

FIG. 16 is a diagram showing the attenuation characteristic of the electrostatic surge countermeasure circuit of the present invention.

FIG. 17 is a diagram showing reflection characteristics of the electrostatic surge countermeasure circuit of the present invention.

FIG. 18 is an equivalent circuit diagram showing an example of an electrostatic surge countermeasure circuit.

FIG. 19 is a block diagram of an EGSM / DCS compatible antenna switch circuit using a PIN diode switch according to a conventional technique.

FIG. 20 is a diagram showing an equivalent circuit of a switch circuit using a PIN diode switch according to a conventional technique.

FIG. 21: EG using a GaAs switch according to the prior art
It is a block diagram of the antenna switch circuit corresponding to SM and DCS.

[Explanation of symbols]

ANT: Antenna terminal TX: Transmission terminal RX: Reception terminal Dip, Dip1, Dip2: Diplexer Dup: Duplexer LPF1, LPF2: Low pass filter SW, SW1, SW2: Switch circuit VNF: Variable notch filter L1 to L17: Transmission line, inductor or Choke coils C, C1 to C19: Capacitance D: PIN diode R: Resistors VC, VC1, VC2, VC3: Control power supply 1: Multilayer dielectric 2: SPDT GaAs FET switch 3: Diode switch 4: Chip capacitor 5: Choke coil 6 : Chip resistor 7: Side electrode terminal

Claims (16)

[Claims] 1. A first transmission terminal, a second reception terminal, and a first
, A second diplexer having a second transmission terminal, a first reception terminal, and a second common terminal, a first transmission / reception terminal, a second transmission / reception terminal, and an antenna terminal And a switch circuit in which one of the first transmission / reception terminal and the second transmission / reception terminal is switchably connected to the antenna terminal, and the first common terminal is the first transmission / reception terminal. It is connected to a transmission / reception terminal, the second common terminal is connected to the second transmission / reception terminal, and is input to the first transmission terminal or the second transmission terminal between the switch circuit and the antenna. Transmission signal 2
A multiband antenna switch circuit having a filter for attenuating a frequency doubled or tripled. 2. The filter is a notch filter,
The multi-band antenna switch circuit according to claim 1, further comprising an inductor, a diode, a capacitor, a resistor, and a power supply terminal, wherein a resonance frequency is variable by a voltage applied to the power supply terminal. 3. A first transmission terminal, a second reception terminal, and a first
, A second diplexer having a second transmission terminal, a first reception terminal, and a second common terminal, a first transmission / reception terminal, a second transmission / reception terminal, and an antenna terminal And a switch circuit in which one of the first transmission / reception terminal and the second transmission / reception terminal is switchably connected to the antenna terminal, and the first common terminal is the first transmission / reception terminal. A multi-band antenna switch circuit connected to a transmission / reception terminal, the second common terminal connected to the second transmission / reception terminal, and a notch filter provided between the switch circuit and the antenna. 4. The multiband according to claim 3, wherein the notch filter has an inductor, a diode, a capacitor, a resistor, and a power supply terminal, and a resonance frequency is variable depending on a voltage applied to the power supply terminal. Antenna switch circuit. 5. The multi-band antenna switch circuit according to claim 2, wherein the notch filter has a reverse voltage terminal for applying a reverse voltage to the diode. 6. A first inductor having an input terminal and an output terminal, connected between the input terminal and a ground, a first capacitor connected between the input terminal and the output terminal, A high-pass filter including a second inductor connected to the output terminal and a second capacitor connected to the ground and the second inductor is provided at least between the notch filter and the antenna. The multi-band antenna switch circuit according to claim 2. 7. A third inductor and a third inductor between the second inductor of the high pass filter and the output terminal.
The multi-band antenna switch circuit according to claim 6, wherein a parallel resonant circuit having the capacitance of 1 is inserted. 8. A first transmitting terminal, a second receiving terminal, and a first
, A second diplexer having a second transmission terminal, a first reception terminal, and a second common terminal, a first transmission / reception terminal, a second transmission / reception terminal, and an antenna terminal And a switch circuit in which one of the first transmission / reception terminal and the second transmission / reception terminal is switchably connected to the antenna terminal, and the first common terminal is the first transmission / reception terminal. A filter for absorbing a surge voltage due to electrostatic discharge to the ground between the switch circuit and the antenna, the filter being connected to the transmitting / receiving terminal, the second common terminal being connected to the second transmitting / receiving terminal. Multi-band antenna switch circuit. 9. The first inductor, wherein the filter has an input terminal connected to the antenna and an output terminal connected to the switch circuit, and is connected between the input terminal and ground, and the input terminal. And a second capacitor connected to the output terminal, a second inductor connected to the output terminal, and a second capacitor connected to the ground. 9. The multi-band antenna switch circuit according to claim 8, which is provided. 10. A first diplexer having a first transmission terminal, a second reception terminal, and a first common terminal, and a second diplexer having a second transmission terminal, a first reception terminal, and a second common terminal. A second diplexer, a first transmission / reception terminal, a second transmission / reception terminal, and an antenna terminal, and one of the first transmission / reception terminal and the second transmission / reception terminal is switchably connected to the antenna terminal. Between the switch circuit and the antenna, wherein the first common terminal is connected to the first transmission / reception terminal, the second common terminal is connected to the second transmission / reception terminal, and A first inductor having an input terminal connected to the antenna and an output terminal connected to the switch circuit, the first inductor being connected between the input terminal and ground, the input terminal and the output terminal Connected between Multiband antenna switch having a first capacitor, a second inductor connected to the output terminal, and a high-pass filter including the second inductor and a second capacitor connected to the ground. circuit. 11. The parallel resonant circuit including a third inductor and a third capacitor is inserted between the second inductor of the high pass filter and the output terminal, according to claim 9 or 10. Multi-band antenna switch circuit. 12. A first diplexer having a first transmission terminal, a second reception terminal, and a first common terminal, and a second diplexer having a second transmission terminal, a first reception terminal, and a second common terminal. A second diplexer, a first transmission / reception terminal, a second transmission / reception terminal, and an antenna terminal, and one of the first transmission / reception terminal and the second transmission / reception terminal is switchably connected to the antenna terminal. Between the switch circuit and the antenna, wherein the first common terminal is connected to the first transmission / reception terminal, the second common terminal is connected to the second transmission / reception terminal, and And a filter that absorbs a surge voltage due to electrostatic discharge to the ground, and a filter that attenuates a frequency that is twice or three times the frequency of the transmission signal input to the first transmission terminal or the second transmission terminal. Characteristic Multi-band antenna switch circuit. 13. A first device connected to the first transmission terminal.
13. The multiband antenna switch circuit according to claim 1, further comprising: a lowpass filter according to claim 1 and a second lowpass filter connected to the second transmission terminal. 14. The multiband antenna switch circuit according to claim 1, wherein the switch circuit is made of a GaAs semiconductor. 15. A multi-band antenna switch circuit according to claim 1, wherein a part of a transmission line and a capacitance constituting the multi-band antenna switch circuit is built in a laminated substrate to constitute a part of the multi-band antenna switch circuit. Switch element,
Multi-band antenna switch multi-layer module composite part characterized in that chip parts such as resistors, capacitors and inductors are mounted on a multi-layer board. 16. The multiband antenna switch circuit according to claim 1, or 15.
A communication device using the multi-band antenna switch laminated module composite component described.