Multi-band transceiver and radio communication device using the transceiver

The present invention relates to a multi-band transceiver (transmitter-receiver) used in a front-end unit of a cellular phone or a radio communication device, and a radio communication device using the multi-band transceiver.

In recent years, a cellular phone of a multi-band system that mounts transmitting-receiving systems of multiple communication systems in a single cellular phone, and can select them in accordance with regional characteristics and purposes for use is introduced. The cellular phone of the multi-band system must be provided with a transmitting-receiving circuit of each communication system and a branching circuit that branches a frequency band of the communication system. If each component is mounted individually, however, the cellular phone is made large, and leads to being increasingly expensive.

Concerning this type of problem, for example, a multi-band transceiver shown in Japanese Patent Laid-Open No. 2003-8470 (USP2002-196085) is disclosed. This multi-band transceiver integrates a branching circuit, a switching circuit that switches the transmitting-receiving circuit of each communication system, a power amplifier for amplifying a transmitted signal, and a coupler for monitoring the output of the power amplifier. The multi-band transceiver forms a matching circuit unit of the branching circuit, the switching circuit, the coupler, and the power amplifier in a dielectric substrate, and mounts diodes or elements of an amplifier circuit of the power amplifier on this substrate. Consequently, a high frequency circuit unit of the multi-band cellular phone is miniaturized and realizes cost reduction.

The multi-band cellular phone of JP-B No. 8470/2003, however, is limited to a communication system, such as a GSM (global system for mobile communications) or a DCS (digital cellular system) according to TDMA (time division multiple access), and cannot be used in the communication system including CDMA (code division multiple access).

To realize a multi-band transceiver that can be used in the multi-band cellular phone including the CDMA, the switching circuit unit of the aforementioned multi-band transceiver can be replaced by an antenna shared device consisting of a matching circuit between a transmitting filter, a receiving filter, and a filter. Usually, a SAW filter is used here as the transmitting filter or the receiving filter.

A SAW filter is basically composed of a piezoelectric substrate and a IDT (Inter Digitated Transducer) electrode consisting of a conductor thin film formed on the surface of this substrate. A material having excellent characteristics is selected as the piezoelectric substrate. The piezoelectric substrate used practically as the SAW filter for a cellular phone has a temperature characteristic in the level of several ten ppm. Further, a thin film, such as Al or an Al alloy, is used as a conductor of the IDT (Inter Digitated Transducer) electrode. Because an antenna shared device according to the present invention handles relatively high power, the damage of a SAW filter causes a problem. The damage of this SAW filter occurs because the IDT electrode deteriorates due to a stress migration caused by the excitation and propagation of a surface acoustic wave, and the damage tends to be accelerated with temperature.

The aforementioned multi-band transceiver, however, mounts a semiconductor device for an amplifier circuit and a SAW filter on a mounting substrate. When a cellular phone is in a speech mode, the heat generated from the amplifier circuit is transferred to the SAW filter. As a result, the characteristic deterioration of the SAW filter occurs by the effects of heat. If a high output signal is input to the SAW filter in a high temperature state, a considerable reduction in reliability, such as the SAW filter is damaged easily, is predicted.

Further, as the technology that prevents the effects of temperature on the frequency characteristics of the SAW filter, there is a technology of improving a temperature characteristic by forming a material layer having the temperature characteristic that differs from a piezoelectric substrate material on the surface of a piezoelectric substrate or the surface of the piezoelectric substrate on which an electrode is formed.

For example, in a Y-cut X propagation tantalum oxide lithium single crystal (Y-X LiTaO3) used widely in a high frequency application, a frequency temperature coefficient is about −35 ppm. When ambient temperature rises, a frequency characteristic shifts to the low frequency side. For example, if a silicon dioxide (SiO 2 ) thin film is formed on the surface as a material having a rear temperature characteristic, it is known that mutual temperature characteristics are offset and a filter temperature characteristic is improved. In this case, the optimum value is selected to offset the temperature characteristic concerning the film thickness of SiO 2 , and, normally, the film thickness of several percent to several ten percent of a SAW wavelength excited by a filter electrode is used.

Because a thin film for temperature characteristic compensation is additionally formed on the surface by the aforementioned temperature characteristic improving means, the thickness of this thin film affects the excitation or propagation characteristic of the SAW filter. Accordingly, because the film thickness cannot be controlled satisfactorily by the present technology, characteristic dispersion is caused.

Because the characteristic dispersion resulting in such type of process becomes a big problem on the mass production of a SAW filter, an improving means that does not depend on the aforementioned thin film formation is strongly desired to suppress the effects of heat and realize more stable performance in a transceiver that uses the SAW filter.

The present invention solves the aforementioned problems, and an object is to prevent the performance deterioration of the entirety of a multi-band transceiver due to the generation of heat from a semiconductor device for an amplifier circuit.

A further object is to provide a compact, low-cost, and high-reliability multi-band transceiver.

The multi-band transceiver of the present invention has a function of sharing transmitted and received signals of multiple frequency bands by the same antenna. The multi-band transceiver mounts multiple filters that correspond to the multiple frequency bands and multiple amplifiers for amplifying the transmitted signals on the same substrate, and arranges the multiple filters in close vicinity to the amplifier in the order where the multiple filters are excellent in their temperature characteristic.

The multi-band transceiver of the present invention has the function of sharing transmitted and received signals of multiple frequency bands by the same antenna. The multi-band transceiver mounts multiple filters that correspond to the multiple frequency bands and multiple amplifiers for amplifying the transmitted signals on the same substrate, and arranges the multiple filters in close vicinity to the amplifier in the order where the filter excellent in its temperature characteristic is preferentially arranged. At the same time, the multi-band transceiver arranges at least one other amplifier between a filter arranged in closest vicinity to the amplifier and an amplifier that operates in a frequency band corresponding to this filter.

The multi-band transceiver of the present invention is provided with a first shared device for performing the transmission and reception of a first communication system, a second shared device for performing the transmission and reception of a second communication system, a first amplifier for amplifying the transmitted signal of the first communication system, a second amplifier for amplifying the transmitted signal of the second communication system, and a frequency switching circuit for switching frequency bands of the first and second communication systems. The multi-band transceiver mounts a first transmitting filter that constitutes the first shared device, a first receiving filter that forms the first shared device, a second transmitting filter that constitutes the second shared device, a second receiving filter that forms the second shared device, the first amplifier, and the second amplifier on the same substrate. In multi-band transceiver the distance between the first transmitting filter or the first receiving filter and the first amplifier or the second amplifier is made larger than the distance between the second transmitting filter or the second receiving filter and the first amplifier or the second amplifier.

The multi-band transceiver of the present invention is provided with a first shared device for performing the transmission and reception of a first communication system, a second shared device for performing the transmission and reception of a second communication system, a first amplifier for amplifying the transmitted signal of the first communication system, a second amplifier for amplifying the transmitted signal of the second communication system, and a frequency switching circuit for switching frequency bands of the first and second communication systems. The multi-band transceiver mounts a first transmitting filter that constitutes the first shared device, a first receiving filter that forms the first shared device, a second transmitting filter that constitutes the second shared device, a second receiving filter that forms the second shared device, the first amplifier, and the second amplifier on the same substrate. In the multi-band transceiver, the distance between the first transmitting filter or the first receiving filter and the first amplifier or the second amplifier is made larger than the distance between the second transmitting filter or the second receiving filter and the first amplifier or the second amplifier. In addition, the second transmitting filter and the second receiving filter are arranged between the first transmitting filter/the first receiving filter and the first amplifier/the second amplifier.

Desirably, in the multi-band transceiver of the present invention each of the multiple filters is formed through a different process and has a different temperature characteristic.

Further, desirably, in the multi-band transceiver of the present invention a filter located farther from the amplifier corresponds to a communication system of a lower frequency within the multiple frequency bands.

Desirably, in the multi-band transceiver a matching circuit for obtaining the matching between the transmitting and receiving filters that correspond to each frequency band, at least a part of the matching circuits of the amplifier, and a part of the frequency switching circuits for switching the frequency band are arranged on the surface or inside of the substrate.

Desirably, in the multi-band transceiver of the present invention an electrode pattern leading into a ground electrode via a through hole between the amplifier and the filter arranged in close vicinity and/or between the filter arranged in close vicinity and another filter is formed on a dielectric layer that constitutes the substrate.

Further, in the multi-band transceiver a recessed part for housing at least one of the transmitting filter, the receiving filter, and the amplifier can be provided on at least either the surface or rear of the substrate.

Desirably, in the multi-band transceiver of the present invention the substrate is formed with either a ceramics or resin substrate.

Desirably, in the multi-band transceiver of the present invention the ceramics is Low Temperature Co-fired Ceramics (LTCC).

Desirably, in the multi-transceiver of the present invention the substrate is a composite material of resin and ceramics.

In a radio communication device of the present invention having a transmission and reception function in multiple frequency bands, the multi-band transceiver of the present invention is arranged between an antenna and multiple high frequency circuits that correspond to the multiple frequency bands. The radio communication device is provided with a control unit that controls operation conditions of the high frequency circuit and the multi-band transceiver in accordance with the frequency band used in communication.

In the radio communication device of the present invention having a transmission and reception function in multiple frequency bands, the multi-band transceiver of the present invention between an antenna and multiple high frequency circuits that correspond to the multiple frequency bands is arranged. The radio communication device is provided with a control unit that controls operation conditions of the high frequency circuit and the multi-band transceiver in accordance with the frequency band used in communication. When the radio communication device performs communication in the frequency band that corresponds to the filter arranged in closest vicinity to the amplifier, the control unit controls the processing so that the amplifier other than the amplifier that is closest to the filter arranged in closest vicinity can be operated.

FIG. 1 shows a circuit diagram of a multi-band transceiver of the present invention.

FIG. 2 is a perspective view of a first embodiment of the multi-band transceiver of the present invention.

FIG. 3 is a top view of the multi-band transceiver of the first embodiment.

FIG. 4 is an exploded view of a dielectric sheet that constitutes a substrate on which the multi-band transceiver of the first embodiment is mounted.

FIG. 5 is a perspective view of the multi-band transceiver of the first embodiment after it is sealed with resin.

FIG. 6 is a drawing showing another method of sealing with resin of the first embodiment.

FIG. 7 is a perspective view showing a modification example of the first embodiment of the multi-band transceiver of the present invention.

FIG. 8 is a perspective view of a second embodiment of the multi-band transceiver of the present invention.

FIG. 9 is a top view of the multi-band transceiver of the second embodiment.

FIG. 10 is a perspective view of the multi-band transceiver of the second embodiment after it is sealed with the resin.

FIG. 11 is a perspective view of a third embodiment of the multi-band transceiver of the present invention.

FIG. 12 is a top view of the multi-band transceiver of the third embodiment.

FIG. 13 is a perspective view of the multi-band transceiver of the third embodiment after it is sealed with the resin.

FIG. 14 is a perspective view of a fourth embodiment of the multi-band transceiver of the present invention.

FIG. 15 is a perspective view of a fifth embodiment of the multi-band transceiver of the present invention.

FIG. 16 is an exploded perspective view of the dielectric sheet that constitutes a mounting substrate of the fifth embodiment.

FIG. 17 is a circuit diagram of a sixth embodiment of the multi-band transceiver of the present invention.

FIG. 18 is a perspective view of the multi-band transceiver of the sixth embodiment.

FIG. 19 is a top view of the multi-band transceiver of the sixth embodiment.

FIG. 20 is a perspective view of the multi-band transceiver of the sixth embodiment after it is sealed with the resin.

FIG. 21 is a circuit diagram of a seventh embodiment of the multi-band transceiver of the present invention.

FIG. 22 is a perspective view of the multi-band transceiver of the seventh embodiment.

FIG. 23 is a top view of the multi-band transceiver of the seventh embodiment.

FIG. 24 is a perspective view of the multi-band transceiver of the seventh embodiment after it is sealed with the resin.

FIG. 25 is a perspective view of the modification example of the multi-band transceiver of the seventh embodiment.

FIG. 26 is a function block diagram showing the configuration of the multi-band transceiver of an eighth embodiment.

First Embodiment

A first embodiment according to the present invention is shown in FIGS. 1 to 6 .

FIG. 1 is a circuit diagram of a multi-band transceiver, and FIG. 2 is a perspective view of this embodiment. FIG. 3 is a top view of this embodiment. FIG. 4 is an exploded view of a dielectric sheet that comprises a mounting substrate of this embodiment. FIGS. 5 and 6 are perspective views of this embodiment.

(Circuit Configuration)

The multi-band transceiver of this embodiment, as shown in FIG. 1 , is provided with a branching filter Dip that is a frequency switching circuit, an antenna shared device Dup 1 of a first communication system, a first amplifier PM 1 for amplifying a transmitted signal of the first communication system, an antenna shared device Dup 2 of a second communication system, and a second amplifier PM 2 for amplifying the transmitted signal of the second communication system. The branching filter Dip connects a low-pass filter consisting of capacitors C 1 , C 2 , and C 3 and an inductor L 1 between an ANT terminal and a common terminal com 1 of the shared device Dup 1 , and connects a high-pass filter consisting of capacitors C 4 and C 5 and an inductor L 2 between the ANT terminal and a common terminal com 2 of Dup 2 . In this embodiment, the communication frequency band of the first communication system is separated from the communication frequency band of the second communication system by about 1,000 MHz, and the first communication system uses a band on the low frequency side and the second communication system uses a band on the high frequency side. The Dup 1 consists of two filters S 1 and S 2 and a matching circuit mc 1 and the Dup 2 consists of two filters F 1 and F 2 and a matching circuit mc 3 . Further, the PM 1 consists of an amplifier circuit P 1 , a matching circuit mc 2 , and a capacitor C 8 . The PM 2 consists of an amplifier circuit P 2 , a matching circuit mc 4 , and a capacitor C 9 . In this embodiment, the S 1 and S 2 are the SAW filters and the F 1 and F 2 are the FBAR filters.

When the first communication system is utilized, a transmitted signal input from a transmitting terminal Tx 1 is amplified in the amplifier circuit P 1 of the amplifier PM 1 and input to the filter S 1 of the Dup 1 . The matching circuit mc 2 and the C 8 of the PM 1 are circuits for obtaining the impedance matching between the P 1 and the filter S 1 of the Dup 1 , and transferring the transmitted signal amplified by the P 1 to the S 1 effectively. A capacitor C 6 cuts a direct current from the amplifier PM 1 . The S 1 transfers a signal to a branching filter with a low loss. At this occasion, the impedance of the filter S 2 viewed from the filter S 1 reaches high impedance due to the effects of the matching circuit mc 1 , and the transmitted signal is not leaked to a receiving terminal Rx 1 . The transmitted signal input from the Dup 1 to the branching filter Dip is output to the ANT terminal and is radiated from an antenna to the air. At this occasion, the high-pass filter of the branching filter Dip attenuates a transmitted signal. Accordingly, the leakage of the signal into the circuit on the second communication system side is reduced, and a wrong operation of a cellular phone can be prevented.

Conversely, a received signal received from an antenna is input from the ANT terminal to the branching filter Dip. The received signal is input from the low pass filter of the branching filter Dip to the filter S 2 via the matching circuit mc 1 of the Dup 1 . The S 2 transfers the signal to the receiving terminal Rx 1 with a low loss. At this occasion, the impedance of the S 1 viewed from the S 2 reaches exceedingly high impedance, and the received signal is not leaked to the amplifier PM 1 .

When the second communication system is utilized, the transmitted signal input from a transmitting terminal Tx 2 is amplified in the amplifier circuit P 2 of the amplifier PM 2 and input to the filter F 1 of the Dup 2 . The matching circuit mc 4 and C 9 of the PM 2 are circuits for obtaining the impedance matching between the P 2 and the filter F 1 of the Dup 2 and transferring the transmitted signal amplified by the P 2 to the F 1 effectively. A capacitor C 7 cuts a direct current from the amplifier PM 2 . The F 1 transfers a signal to a branching filter with a low loss. At this occasion, the impedance of the filter F 2 viewed from the filter F 1 reaches exceedingly high impedance due to the effects of the matching circuit mc 3 of the Dup 2 , and the transmitted signal is not leaked into a receiving terminal Rx 2 . The transmitted signal input from the Dup 2 to the branching filter Dip is output to the ANT terminal and is radiated from an antenna to the air. At this occasion, the low-pass filter of the branching filter Dip attenuates the transmitted signal. Accordingly, the leakage of the signal into the circuit on the first communication side is reduced, and a wrong operation of a cellular phone can be prevented.

On the other hand, the received signal received from the antenna is input from the ANT terminal to the branching filter Dip. The received signal is input from the high-pass filter of the branching filter Dip to the filter F 2 via the matching circuit mc 3 of the Dup 2 . The F 2 transfers the signal to the receiving terminal Rx 2 with a low loss. At this occasion, the impedance of the F 1 viewed from the F 2 reaches high impedance, and the received signal is not leaked to the amplifier PM 2 .

(Filter Arrangement)

FIG. 2 shows a perspective view of this embodiment. The multi-band transceiver of this embodiment mounts the filters F 1 and F 2 of the Dup 1 , the filters F 1 and F 2 of the Dup 2 , the amplifier circuit P 1 of the amplifier PM 1 , the amplifier circuit P 2 of the amplifier PM 2 , a chip element 2 that forms the direct current cut capacitors C 6 and C 7 of the amplifier, and a chip element 3 that forms the capacitors C 4 , C 5 , and C 6 and the inductor L 1 on the top of the mounting substrate 1 . In this embodiment, the FBAR filters F 1 and F 2 excellent in a thermal characteristic in comparison with the SAW filter are arranged between the amplifier circuits P 1 /P 2 and the SAW filters S 1 /S 2 . Each of the filters and amplifier circuits adheres on the mounting substrate with an adhesive material. Further, an electrode 4 is arranged around each of the filters and amplifiers, and a wire 5 connects an input-output electrode or ground electrode of the filter with the electrode 4 . Accordingly, each of the filters and amplifier circuits connects with the circuit inside the mounting substrate.

This arrangement method becomes difficult to transfer the heat generated from the P 1 and P 2 to the SAW filters S 1 and S 2 because the FBAR filters F 1 and F 2 are arranged halfway. Accordingly, even if the SAW filter is used for a long time, the damage of the SAW filter due to the characteristic deterioration of the SAW filter and the deterioration in the power resistance of the SAW filter under high temperature is reduced greatly. Conversely, the FBAR filter arranges a film composed of a piezoelectric substance, such as AIN or ZnO, between flat thin film electrodes composed of a conductive material, such as A 1 , and utilizes the vibration of this piezoelectric film. Accordingly, the FBAR filter is more excellent than the SAW filter that forms a micro cord thin film electrode on a piezoelectric substrate, in the power resistance at high temperature. Accordingly, even if a high output signal is input from an amplifier, the FBAR filter is not damaged.

FIG. 3 is a top view of this embodiment. The matching circuits mc 1 and mc 3 of an antenna shared device, a part of the matching circuits mc 2 and mc 4 of an amplifier, and a part of the branching filters Dips are formed inside the mounting substrate 1 . Multiple dielectric sheets are laminated on the mounting substrate 1 . The mc 1 , mc 2 , mc 3 , mc 4 , and L 2 are formed on these dielectric sheets as strip line electrodes, and the C 1 , C 2 , and C 3 are formed as opposed flat electrodes extending over the multiple dielectric sheets. In this embodiment, the mc 1 is formed in an area 6 enclosed by a dashed line, and the mc 3 is formed in an area 7 enclosed by a dashed line. A part of the branching filter circuits L 2 , C 1 , C 2 , and C 3 is formed in an area 8 enclosed by a dashed line.

(Laminated Structure)

FIG. 4 is an exploded view of a dielectric sheet that comprises a mounting substrate of this embodiment. Electrodes 9 a , 9 b , 13 a , 13 b , 14 a , 14 b , 15 a , and 15 b are formed on the top of a dielectric sheet 1 a . The electrodes 13 a and 13 b mount the SAW filters S 2 and S 1 respectively. The electrodes 14 a and 14 b mount the FBAR filters F 1 and F 2 respectively. The electrodes 15 a and 15 b mount the amplifier circuits P 2 and P 1 respectively. A ground electrode 12 formed on the bottom of a dielectric sheet 1 c connects with the electrodes 15 a and 15 b via a through hole 10 . Accordingly, a part of the heat generated from the amplifier circuit can escape from a reverse ground electrode 12 to a motherboard of a cellular phone via the through hole 10 . The electrodes 9 a and 9 b connect with a through hole 9 c formed on a dielectric sheet 1 b and the dielectric sheet 1 c . The through hole 9 c connects with the ground electrode 12 . Accordingly, the heat generated from the amplifier circuit can escape from the reverse ground electrode 12 to the motherboard of the cellular phone via the through hole, and the amount of heat transfer into a filter can be reduced. In particular, because the two electrodes 9 a and 9 b are arranged between the SAW filters S 1 /S 2 and the amplifier circuit, ahigher effect can be obtained.

Electrodes 11 a and 11 b formed on the top of the dielectric sheet 1 b are strip line electrodes on which the matching circuits mc 4 and mc 2 are formed. Generally, a first communication system having a low communication frequency requires a matching circuit electrode of a longer amplifier than a second communication system having a high communication frequency. According to a filter arrangement method of this embodiment, the distance between the SAW filter and the amplifier circuit of the first communication system becomes larger than the distance of the FBAR filter and the amplifier circuit of the second communication system. Accordingly, a strip line electrode of the long matching circuit mc 2 can be formed efficiently.

(Sealed Structure)

FIG. 5 shows a perspective view of this embodiment. After a filter, an amplifier circuit, and a chip element are mounted on the top of the mounting substrate 1 , the SAW filters S 1 and S 2 , the FBAR filters F 1 and F 2 , and the amplifier circuit P 1 and P 2 are hermetically sealed by a resin material 16 . Accordingly, each filter or amplifier circuit can be protected from the damage by a contact or deterioration by exposure to the air.

FIG. 6 is a drawing showing another hermetic seal method of this embodiment. The SAW filters S 1 and S 2 and the FBAR filters F 1 and F 2 , and the amplifier circuits P 1 and P 2 are hermetically sealed with resin materials 16 a and 16 b respectively. This method reduces the amount of heat transferred from an amplifier circuit to a SAW filter via a resin material. Accordingly, the characteristic deterioration due to the heat of the SAW filter is reduced further, and a higher reliability multi-band transceiver can be realized.

(Modification Example)

FIG. 7 is a modification example of a mounting method of this embodiment. In this example, the amplifier circuit P 1 is arranged adjacently to the FBAR filters F 1 and F 2 , but the amplifier circuit P 2 is arranged between the FBAR filters F 1 and F 2 via the amplifier circuit P 1 . In this case, when a first communication system is operating, the FBAR filters F 1 and F 2 are inserted between the amplifier circuit P 1 and the SAW filters S 1 /S 2 . Accordingly, the transfer of the heat from the amplifier P 1 to the SAW filter S 1 and S 2 can be reduced.

Conversely, when a second communication system is operating, the amplifier circuit P 1 is inserted between the amplifier circuit P 2 and the FBAR filters F 1 /F 2 . Accordingly, the transfer of the heat from the amplifier circuit P 2 to the FBAR filters F 1 and F 2 can be reduced. This arrangement method can increase the distance between the filter and the amplifier circuit that correspond to each communication system, and insert a filter or an amplifier circuit of another communication system between the filter and the amplifier circuit. Accordingly, even if which communication system is used, a multi-band transceiver that operates stably can be realized.

Second Embodiment

Next, a second embodiment according to the present invention is shown in FIGS. 8 to 10 . FIG. 8 is a perspective view of this embodiment. FIG. 9 is a top view of this embodiment. FIG. 10 is a perspective view of this embodiment.

In this embodiment, as shown in FIG. 8 , the filters S 1 and S 2 of the Dup 1 , the filters F 1 and F 2 of the Dup 2 , the amplifier circuit P 1 of the amplifier PM 1 , the amplifier circuit P 2 of the amplifier PM 2 , a chip element 22 that forms a part of the matching circuits mc 2 and mc 4 of the amplifier, and a chip element 23 that forms a part of branching filters Dips on the top of amounting substrate 21 are mounted. In this embodiment, the amplifier circuits P 1 and P 2 and the SAW filters S 1 and S 2 are arranged on a diagonal line on the top of the mounting substrate 21 , and the FBAR filters F 1 and F 2 are arranged in the traverse part between them. This arrangement method can arrange the FBAR filters F 1 and F 2 between the amplifier circuits P 1 /P 2 and the SAW filters S 1 /S 2 , and increase the distance between the P 1 /P 2 and the S 1 /S 2 . Accordingly, the transfer of the heat generated from the amplifier circuit into the SAW filter can be reduced.

FIG. 9 shows a top view of the second embodiment. The matching circuits mc 1 and mc 3 of an antenna shared device, a part of the matching circuits mc 2 and mc 4 of an amplifier, and a part of branching filters Dips are formed inside the mounting substrate 21 . Multiple dielectric sheets are laminated on the mounting substrate 21 . The mc 1 , mc 2 , mc 3 , mc 4 , and L 2 are formed on these dielectric sheets as strip line electrodes. C 1 , C 2 , and C 3 are formed and incorporated as opposed flat electrodes extending over multiple dielectrics. In this embodiment, the mc 1 is formed at a lower layer into which an area 24 enclosed by a dashed line is projected, and the mc 3 is formed at the lower layer of an area 25 enclosed by a dashed line. Further, a part of the branching filters L 2 , C 1 , C 2 , and C 3 is formed at the lower layer of an area 26 enclosed by a dashed line. Through holes 27 a and 27 b connect with the reverse ground electrode via a through hole, and the heat generated from the amplifier circuit escapes into a motherboard of a cellular phone via the through hole. Accordingly, the transfer of the heat into the SAW and FBAR filters can be reduced. Further, although not shown, multiple through holes are formed from the P 1 or P 2 mounting unit to the reverse ground electrode in the same manner as the first embodiment. Accordingly, a part of the heat generated from the amplifier circuit can be transferred into the motherboard of the cellular phone.

FIG. 10 is a perspective view of this embodiment. After a filter, an amplifier circuit, and a chip element are mounted on the top of the mounting substrate 21 , the SAW filters S 1 and S 2 and the FBAR filters F 1 and F 2 are hermetically sealed with a resin material 28 a , and the amplifiers P 1 and P 2 are hermetically sealed with a resin material 28 b . Accordingly, each filter and amplifier circuit can be protected from the damage due to a contact and the deterioration due to exposure to the air. Further, because the amplifier circuit and filter are sealed with another resin material respectively, the transfer of the heat from the amplifier circuit to the SAW filter via the resin material is reduced. Accordingly, the reliability of a multi-band transceiver is improved further.

Third Embodiment

Next, a third embodiment according to this embodiment is shown in FIGS. 11 to 13 . FIG. 11 is a perspective view of this embodiment. FIG. 12 is a top view of this embodiment, and FIG. 13 is a perspective view of this embodiment. In this embodiment, as shown in FIG. 11 , the filters S 1 and S 2 of the Dup 1 , the filters F 1 and F 2 of the Dup 2 , the amplifier circuit P 1 of the amplifier PM 1 , the amplifier circuit P 2 of the amplifier PM 2 , chip elements 32 a and 32 b that form the matching circuits mc 2 and mc 4 of the amplifier, and a chip element 33 that forms a part of the branching filters Dips on the top of a mounting substrate 31 . In this embodiment, the amplifier circuit P 1 , the FBAR filter F 2 , and the SAW filter S 1 are arranged at one side on the top of the mounting substrate 31 in columns, and the amplifier circuit P 2 , the FBAR filter F 1 , and the SAW filter S 1 are arranged at the other side on the top of the mounting substrate 31 in columns, then the chip element 33 is arranged in the central part of the mounting substrate in columns. Subsequently, each column arranges an FBAR filter between an amplifier circuit and a SAW filter. This arrangement method can increase the distance between the SAW filters S 1 /S 2 and the FBAR filters F 1 /F 2 . Accordingly, the interference generated by arranging a filter element in close vicinity decreases, and the isolation characteristic of each antenna shared device is improved from a transmitting terminal to a receiving terminal. Further, because the amplifier circuit P 1 or the SAW filter S 1 and the amplifier circuit P 2 or the FBAR filter F 1 are arranged in the same column, the matching circuits mc 2 or mc 4 of the amplifier circuit can be arranged efficiently.

FIG. 12 is a top view of this embodiment. In the same manner as the aforementioned embodiment, a part of the matching circuits mc 1 to mc 4 and a part of branching filter circuits are formed inside the mounting substrate 31 . In this embodiment, the matching circuit mc 1 , the matching circuit mc 3 , and a part of the branching filter circuits are formed in an area 34 enclosed by a dashed line, in an area 35 , and in an area 36 , inside a dielectric sheet, respectively. An electrode 37 is connected to the reverse ground electrode via a through hole, and a part of the heat generated from an amplifier circuit escapes from the reverse ground electrode via the through hole to a motherboard of a cellular phone. Accordingly, the transfer of heat into a filter can be reduced.

FIG. 13 shows a perspective view of this embodiment. In this embodiment, the amplifier circuit P 1 , the SAW filter S 1 , the FBAR filter F 2 , and the chip element 32 a are hermetically sealed with a resin material 38 a , and the amplifier circuit P 2 , the SAW filter S 2 , the FBAR filter F 1 , and the chip element 32 b are hermetically sealed with a resin material 38 b respectively. Accordingly, a filter or an amplifier circuit is protected from being damaged by a contact and deteriorating by being exposed to the air.

Fourth Embodiment

Next, a fourth embodiment according to this embodiment is shown in FIG. 14 . FIG. 14 is a perspective view of this embodiment. The structure of this embodiment is the same as the first embodiment. A recessed part is provided on the top of a mounting substrate 41 , and the filters S 1 , S 2 , F 1 , and F 2 and the amplifier circuits P 1 and P 2 are housed here. Each recessed part of the mounting substrate 41 has almost the same thickness of the filter or amplifier circuit to be housed, and the height on the top of the filter or amplifier circuit becomes almost the same height as the top of the mounting substrate when housed. Further, an electrode 44 is arranged around the recessed part and a wire 45 connects between the electrode 44 and a connecting terminal provided on the top of the filter or amplifier circuit. At this occasion, because the electrode 44 and the connecting terminal of the filter or amplifier circuit are located at almost the same height, the wire can be connected easily. Further, when the filter or amplifier circuit is hermetically sealed with the same resin material as the first embodiment, the thickness of the resin material can be thinned because the filter or amplifier circuit is housed in the recessed part. Accordingly, a low multi-band transceiver can be realized.

Fifth Embodiment

Subsequently, a fifth embodiment according to this embodiment is shown in FIGS. 15 and 16 . FIG. 15 shows a perspective view of this embodiment, and FIG. 16 shows an exploded perspective view of the mounting substrate. This embodiment is a modification example of a seal method of the first embodiment. A resin material 52 hermetically seals only the SAW filters S 1 and S 2 and the FBAR filters F 1 and F 2 . A metal cover 53 hermetically seals the amplifier circuits P 1 and P 2 by connecting an electrode 54 , provided on the top of a mounting substrate 51 , with a conductive adhesive material and sticking to the mounting substrate 51 .

FIG. 16 is an exploded perspective view of the mounting substrate of this embodiment. An electrode 54 a provided on the top of a dielectric sheet 51 a connects with an electrode 56 formed on a dielectric sheet 51 b via a through hole 59 . The electrode 56 connects with a through hole 58 formed from an amplifier circuit mounting unit to a reverse ground electrode 57 . The electrode 54 a connects with the reverse ground electrode 57 via a through hole 55 . Accordingly, the heat generated from the amplifier circuits P 1 or P 2 and transferred to the metal cover 53 can escape into a motherboard of a cellular phone via the through holes 55 and 58 . Accordingly, the amount of the heat transferred to the SAW and FBAR filters is reduced, and the characteristic deterioration due to the heat of the SAW filter is reduced further. Consequently, a higher reliability multi-band transceiver can be realized.

Sixth Embodiment

(Circuit Configuration)

Next, a sixth embodiment according to this embodiment is shown in FIGS. 17 to 20 . FIG. 17 is a circuit diagram of this embodiment, and FIG. 18 is its perspective diagram. FIG. 19 is a top view of this embodiment, and FIG. 20 is a perspective view of this embodiment. In this embodiment, a multi-band transceiver can be utilized in three different communication systems. As shown in FIG. 17 , a triplexer Tri that is composed of a passive circuit and switches the frequencies of the three communication systems is arranged immediately under an antenna. The antenna shared device Dup 1 of a first communication system, the antenna shared device Dup 2 of a second communication system, the antenna shared device Dup 3 of a third communication system, the amplifier PM 1 for amplifying a transmitted signal of the first communication system, the amplifier PM 2 for amplifying the transmitted signal of the second system, and the amplifier PM 3 for amplifying the transmitted signal of the third communication system are connected to the rear stage. The Dup 1 is provided with the two filters S 1 and S 2 and the matching circuit mc 1 , and the Dup 2 is provided with the two filters F 1 and F 2 and the matching circuit mc 3 . The Dup 3 is provided with the two filters F 3 and F 4 and the matching circuit mc 5 . Further, the PM 1 is provided with the amplifier circuit P 1 , the matching circuit mc 2 , and a C 62 , and the PM 2 is provided with the amplifier circuit P 2 , the matching circuit mc 4 , and a C 64 . The PM 3 is provided with the amplifier circuit P 3 , a matching circuit mc 6 , and a C 66 . In this embodiment, the communication frequency bands of each communication system are separated by 1,000 MHz or more respectively. The first communication system utilizes the lowest band, and the third communication system utilizes the highest frequency band. The second communication system utilizes an intermediate frequency band. Further, the S 1 and S 2 are the SAW filters, and the F 1 , F 2 , F 3 , and F 4 are the FBAR filters.

(Filter Arrangement)

FIG. 18 shows a perspective view of this embodiment. This embodiment mounts the filters S 1 , S 2 , F 1 , F 2 , F 3 , and F 4 , the amplifier circuits P 1 , P 2 , and P 3 , and the chip elements 62 and 63 on the mounting substrate 61 . In this embodiment, the FBAR filters F 1 , F 2 , F 3 , and F 4 are arranged between the amplifier circuits P 1 , P 2 , and P 3 and the SAW filters S 1 and S 2 . This arrangement method enables arrangement of the FBAR filters F 1 , F 2 , F 3 , and F 4 between the amplifier circuits P 1 /P 2 /P 3 and the SAW filters S 1 /S 2 , and can increase the distance between the P 1 , P 2 , and P 3 and the S 1 and S 2 . Accordingly, the transfer of the heat generated from an amplifier circuit into a SAW filter can be reduced. Further, because a filter used in a communication system of a low frequency is separated from the amplifier circuit, the matching circuits mc 2 , mc 4 , and mc 6 of the amplifier circuit can be formed inside the mounting substrate efficiently in the same manner as the first embodiment.

FIG. 19 is atop view of this embodiment. The matching circuits mc 1 , mc 3 , and mc 5 of an antenna shared device, a part of the matching circuits mc 2 , mc 4 , and mc 6 of an amplifier, and a part of the triplexer Tri are formed inside the mounting substrate 61 . Multiple dielectric sheets are laminated on the mounting substrate 61 . The mc 1 , mc 2 , mc 3 , mc 4 , mc 5 , and mc 6 are formed on these dielectric sheets as strip line electrodes, and the C 61 , C 62 , C 63 , C 64 , C 65 , and C 66 are formed as opposed flat electrodes extending over multiple dielectrics. In this embodiment, the mc 1 is formed in an area 66 enclosed by a dashed line, the mc 3 in an area 67 enclosed by a dashed line, and the mc 5 in an area 68 enclosed by a dashed line respectively. An electrode that constitutes a triplexer is formed in an area 69 enclosed by a dashed line. Otherwise, an SP 3 T semiconductor switch composed of a plurality of transistors can be also mounted in the area 69 on the top of the substrate instead of the triplexer Tri. Namely, SP 3 T semiconductor switch is composed of a plurality of circuit utilizing transistors and an input signal is selectively outputted from any one of different three circuits by controlling a bias voltage supplied to the SP 3 T semiconductor switch from outside. In this case, to control the SP 3 T semiconductor switch, a terminal for inputting the bias voltage is formed on a substrate. Even when the communication frequencies of any one set or all of the three communication systems are close to 1,000 MHz, a satisfactory switching operation can be performed.

FIG. 20 is perspective view of this embodiment. After a filter, an amplifier circuit, and a chip element are mounted on the top of the mounting substrate 61 , the SAW filters S 1 and S 2 and the FBAR filters F 1 , F 2 , F 3 , and F 4 are hermetically sealed with a resin material 70 a , and the amplifier circuits P 1 , P 2 , and P 3 are hermetically sealed with a resin material 70 b . Accordingly, each filter or amplifier circuit can be protected from being damaged by a contact or deteriorated by being exposed to the air. Further, because the amplifier and the filter are sealed with another resin material respectively, the transfer of the heat from the amplifier circuit to the SAW filter via the resin material is reduced. Consequently, the reliability of a multi-band transmitter is improved further.

Seventh Embodiment

(Circuit Configuration)

Next, a seventh embodiment according to the present invention is described with reference to FIGS. 21 to 24 . FIG. 21 is a circuit diagram of a multi-band transceiver of the seventh embodiment according to the present invention, and FIG. 22 is its perspective view. FIG. 23 is a top view of this embodiment, and FIG. 24 is a perspective of this embodiment.

FIG. 21 shows a circuit diagram of this embodiment. In this embodiment, the antenna shared device of a first communication system in the first embodiment is provided with a PIN diode and a diode switch composed of a transmission line. The transmitting-end circuit of an antenna shared device Dup 71 of the first communication system is provided with a PIN diode D 71 and a low-pass filter composed of an inductor L 73 and capacitors C 77 , C 78 , and C 79 . The receiving-end circuit of the Dup 71 is provided with a transmission line L 74 , a diode D 72 , capacitors C 82 , C 83 , and C 84 , a resistor R 71 , a SAW filter S 71 , and a direct voltage terminal Vc.

When the first communication system is utilized, a positive direct current voltage is applied to the Vc. Then the PIN diodes D 71 and D 72 enter ON states and reach low impedance. At this occasion, the transmission line L 74 resonates by the PIN diode D 72 that has entered the ON state and the capacitor C 82 , and the impedance in which a receiving-end circuit is viewed from the connection point of the anode of the PIN diode D 72 , a capacitor C 76 , and the transmission line L 74 becomes exceedingly high. As a result, the circuit between the transmitting-end circuit of the Dup 71 and the transmitting signal output terminal Rx 1 is intercepted, and a signal is transferred only to the transmitting-end circuit.

On the other hand, when the voltage of 0 V is applied to the direct current terminal Vc, the PIN diode enters an OFF state and reaches high impedance. As a result, the circuit between the receiving-end circuit of the Dup 71 and the receiving signal input terminal Tx 1 is intercepted, and a signal is transferred only to the receiving-end circuit.

This embodiment is suitable for being used as a multi-band transceiver that corresponds to a cellular phone that uses TDMA in the first communication system.

(Filter Arrangement)

FIG. 22 shows a perspective view of this embodiment. In this embodiment, the filters S 71 , F 1 , and F 2 , the amplifier circuits P 1 and P 2 , chip elements 72 and 73 , the PIN diodes D 71 and D 72 , and a resistor chip element R 71 R are mounted on a mounting substrate 71 . In this embodiment, the FBAR filters F 1 and F 2 are arranged between the amplifier circuit P 1 or P 2 and the SAW filter S 71 . This arrangement method enables arrangement of the FBAR filters F 1 and F 2 between the amplifier circuits P 1 /P 2 and the SAW filter S 71 , and can increase the distance between the P 1 /P 2 and the S 71 . Accordingly, the transfer of the heat generated from the amplifier circuit to the SAW filter is reduced further. Further, because the filter used in a communication system of a low frequency band is separated from the amplifier circuit, the matching circuits mc 71 and mc 73 of the amplifier circuit can be formed in the mounting substrate efficiently in the same manner as the first embodiment.

(Laminated Structure)

FIG. 23 is a top view of this embodiment. A matching circuit mc 72 of an antenna shared device, the inductor L 73 , the transmission line L 74 , a part of the matching circuits mc 71 and mc 73 , and a part of the branching filters Dips are formed inside the mounting substrate 71 . Multiple dielectric sheets are laminated on the mounting substrate 71 . The mc 71 , mc 72 , mc 73 , L 73 , and L 74 are formed on these dielectric sheets as strip line electrodes, and capacitors C 71 , C 72 , C 73 , C 74 , C 75 , and C 76 , the capacitors C 77 , C 78 , and C 79 , and capacitors C 81 and C 86 are formed as opposed flat electrodes extending over the multiple dielectrics. In this embodiment, the mc 72 is formed in an area 74 enclosed by a dashed line, and a part of the electrodes that constitutes a branching filter is formed in an area 75 enclosed by a dashed line.

(Sealed Structure)

FIG. 24 is a perspective view of this embodiment. After a filter, an amplifier circuit, and a chip element are mounted on the top of the mounting substrate 71 , the SAW filter S 71 , the FBAR filters F 1 and F 2 , and the amplifier circuits P 1 and P 2 are hermetically sealed with a resin material 76 . Accordingly, the amplifier circuit can be protected from being damaged by a contact or deteriorated by being exposed to the air, and there liability of a multi-band transceiver is improved.

(Modification Example)

FIG. 25 shows a perspective view of a modification example of the seventh embodiment. In this embodiment, a receiving filter S 71 of the first communication system of the seventh embodiment is composed of an FBAR filter, and an FBAR filter F 81 is mounted on the top of a mounting substrate 81 . By changing all the filters mounted in this manner into FBAR filters, the damage of the filter at high output is prevented and the receiving filter of the communication system on the low frequency side at which the effect of a frequency shift on a temperature change is separated from an amplifier. Consequently, a high-reliability multi-band transceiver can be realized.

[Configuration of Mounting Substrate]

A mounting substrate of a multi-band transceiver can be formed using a low temperature calcined ceramics (LTCC) material or a resin substrate in which the low temperature simultaneous calcination of less than 950 degrees Celsius is enabled. When the substrate is formed with the LTCC, for example, a slurry type dielectric material in which powder whose main ingredients are AL 2 O 3 and SiO 2 and a binder are mixed is molded into a green sheet with a doctor blade. A substrate having a sheet thickness of 40 to 200 μm was used. A penetration hole is formed at the predetermined place of the molded sheet using laser beam. Preferably, the diameter of the penetration hole should be 50 to 200 μm, and, desirably in particular, it should be 100 to 200 μm. Subsequently, a through hole is formed by filling the penetration hole with a conductor paste by screen printing. Further, for example, a silver conductor that constitutes a circuit electrode is screen-printed on sheets. The mounting substrate is constituted by laminating, crimping, and collectively calcining these screen-printed sheets. Further, plating is applied to the surface of the mounting substrate, the electrode mounted on the rear, and the ground electrode. Further, the substrate can be constituted by printing a dielectric paste and a conductor paste respectively. Further, the substrate can be laminated and integrated by printing and baking the conductor pattern on a dielectric substrate.

Here, as the sheet material of the substrate, for example, a dielectric composite containing A 1 , Si, Sr, and Ti of 10 to 60 mass % in the AL 2 O 3 conversion, 25 to 60 mass % in the SiO 2 conversion, 7.5 to 50 mass % in the SrO conversion, and less than 20 mass % in the TiO 2 conversion, and Bi, Na, K, Cu, and Mn of 0.1 to 10 mass % in the Bi 2 O 3 conversion, 0.1 to 5 mass % in the Na 2 O conversion, 0.1 to 5 mass % in the K 2 O, 0.01 to 5 mass % in the CuO conversion, and 0.01 to 5 mass % in the MnO 2 conversion respectively. This dielectric uses a dielectric material of a relative dielectric constant of about 7. Desirably, the relative dielectric constant of the dielectric used is 7 to 100. Further, for example, if a high dielectric constant material of a dielectric constant of 100 or more is used as a dielectric sheet between electrodes that form a capacitor, the capacitor can be also formed in an exceedingly small area. A pattern electrode is formed by printing an Ag paste. Ag—Pd and Cu can also be used other than Ag.

When a mounting substrate is formed using a resin substrate, for example, a photosensitive insulating layer of an epoxy system is formed on a glass epoxy substrate in which a circuit patter is formed with a conductor, such as copper. After a through hole is formed on this photosensitive insulating layer by a photo etching method, an inner layer wiring pattern and a through hole conductor are formed by electrolytic copper plating from thereover. A mounting substrate that incorporates necessary inductors and capacitor patterns can be obtained by repeating the same process subsequently and making into multi-layered structure.

[Configuration of Communication Device]

FIG. 26 shows the configuration of a radio communication device in an eighth embodiment of the present invention. The present invention is an example in which the aforementioned multi-band transceiver is applied to the radio communication device, such as a cellular phone. First and second radio circuits 102 and 103 are connected to a multi-band transceiver 101 corresponding to a frequency band used in communication, and perform the processing of radio modulation and demodulation. A demodulation signal is converted into voice data by a signal processing unit 104 and sent from a speaker 106 . Conversely, a voice input from a microphone 107 is decoded by the signal processing unit 104 and sent to a modulating unit. A control unit 105 controls the multi-band transceiver 101 , the radio circuits 102 and 103 , and the operation of the signal processing unit 104 . For example, when the radio communication device performs communication in the frequency band that corresponds to the first radio circuit 102 , the operation of the first radio circuit 102 is set on and the operation of the second radio circuit 103 is set off. Similarly, the control is performed so that the corresponding parts of the signal processing unit 104 and the multi-band transceiver 101 can be operated. By performing the control so that only the necessary parts can be operated, current consumption can be reduced and the interference between the radio circuits can be suppressed. With regard to the control on the multi-band transceiver 101 , one amplifier of the relevant frequency band is set on and the other amplifier is set off. For example, on a multi-band transceiver mounted on the substrate 21 shown in FIG. 8 , from the left to order, the SAW filters S 1 /S 2 correspond to a first frequency band, the FBAR filters F 1 and F 2 correspond to a second frequency band, the amplifier circuit P 2 correspond to the second frequency band, and the amplifier circuit P 1 correspond to the first frequency band are arranged. At this occasion, when the radio communication device performs communication using the first frequency band, it is preferable that the control unit 105 sets off the amplifier circuit P 2 closest to the SAW filters S 1 /S 2 and set on the amplifier circuit P 1 which is separated from SAW filters S 1 /S 2 . As having stated above, the FBAR filters F 1 and F 2 are excellent in a thermal characteristic in comparison with the SAW filter filters S 1 /S 2 . So that, in this arrangement, because the SAW filters S 1 /S 2 can be made difficult to receive the effects of the heat from the amplifier circuit P 1 while it is operating by making the amplifier circuit P 2 in an operation off state in communication, the effects of suppressing a filter frequency shift of the SAW filters S 1 /S 2 is improved. Still more, in FIG. 26 , two frequency bands are cited as an example. Even when three or more multiple bands are applied, the filter frequency shift can be suppressed to the minimum in the same manner, while attaining miniaturization.

The present invention is not limited to the aforementioned embodiment. In the aforementioned embodiment, the communication frequency of the first communication system is specified as the low frequency side and the communication frequency of the second communication system is specified as the high frequency side. The opposite rule can also be applied. At this occasion, the low-pass and high-pas filters of a branching filter are connected reversely to the case in the aforementioned embodiment, and each filter, matching circuit, or amplifier that can be used in each communication frequency can be selected. Further, the arrangement of the filter, amplifier circuit, or chip element is based on the arrangement method according to claim 1 , and any arrangement is acceptable.

In this embodiment, a chip element was used as a part of branching filters and matching circuits of amplifiers. If the space inside a mounting substrate is not used up, however, all circuits can be also formed using an electrode pattern inside the mounting substrate. At that occasion, the process in which the chip element is mounted can be saved, thereby improving the productivity of a multi-band transceiver.

In this embodiment, a wire is used to connect the electrode of the mounting substrate, the filter, and the amplifier circuit, but the flip chip connection by a metal bump can also be used.

Further, even when an amplifier that can be applicable to multiple frequency bands by one chip instead of multiple amplifiers is used, it is self evident that the effect of suppressing a filter frequency shift is suppressed to the minimum can be obtained by arranging multiple filters in close vicinity to the amplifier in order of an excellent temperature characteristic.

As described above, according to the present invention, the characteristic deterioration of a filter resulting from the heat generated from an amplifier can be prevented, and a multi-band transceiver having exceedingly high reliability can be realized. Further, a compact, low multi-band transceiver can be realized by mounting the filter and the amplifier on a mounting substrate and forming a part of frequency switching circuits, inter-filter matching circuits, and amplifier matching circuits of the amplifier inside the mounting substrate.