JPH11136151A - Receiver and transmitter-receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a receiver which copes with both receiving sensitivity and an anti-interference wave characteristic by connecting a 1st high frequency filter element to the preceding stage of a high frequency amplifier and connecting a 2nd high frequency filter to the subsequent stage of the high frequency amplifier. SOLUTION: A high frequency signal that is inputted to an antenna terminal 12 is inputted to a 1st external terminal 4. A 1st high frequency filter element 1 partially eliminates an image frequency component and other interference wave components of the high frequency signal and an external terminal 5 that is connected to the other input-output terminal of the element 1 outputs the high frequency signal. It is amplified by a high frequency amplifier 8 and inputted to a 3rd external terminal 6 and outputted from a 4th external terminal 7 that is connected to the other input-output terminal of the 2nd high frequency filter element 2 with its image frequency component and other interference wave components further eliminated. A mixer 9 mixes an output of the terminal 7 with an output of a local oscillator 10 to be converted into an intermediate frequency signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a receiver and a transceiver mainly used for wireless communication devices such as a cordless remote controller, a cordless telephone, and a portable telephone.

[0002]

2. Description of the Related Art FIG. 7 is a block diagram showing a configuration of a conventional transceiver.

In FIG. 7, 9 is a mixer, 10 is a local oscillator, 11 is a demodulation circuit, 12 is an antenna terminal, 13 is an intermediate frequency filter, 14 is a receiving amplifier, 15 is a transmitting amplifier, 16 is a high-frequency switch, and 17 is a high-frequency switch. A first terminal of the high-frequency switch, 18 is a second terminal of the high-frequency switch, 19 is a third terminal of the high-frequency switch, 20 is a modulation circuit, 40 is a reception filter, and 41 is a transmission filter.

First, the operation of the conventional receiver will be described. The high-frequency signal input to the antenna terminal 12 is input to the mixer 9 via the switch 18, the reception filter 40, and the reception amplifier 14. Here, the reception filter 40 is used for removing a signal in an unnecessary band, and includes a band pass filter such as a SAW filter or an LC filter. On the other hand, the output of the local oscillator 10 is input to the mixer 9, and the signal from the receiving amplifier 14 is converted into an intermediate frequency signal by mixing. Here, the output frequency of the local oscillator is changed according to the desired channel to be received. The intermediate frequency signal is band-limited by an intermediate frequency filter 13 for channel selection and input to a demodulation circuit 11. Then, a demodulation operation is performed by the demodulation circuit 11. The receiver is configured by the above configuration.

Next, the operation of the transceiver will be described.
In the transceiver, the receiving operation is the same as the operation of the receiver. However, the first terminal 17 and the second terminal 18 of the high-frequency signal changeover switch connected to the antenna terminal 12 are set to be connected during the receiving operation.

The transmission operation will be described. First, the local oscillator 10 is set to the transmission frequency. And the modulation circuit 2
0 modulates the output signal of the local oscillator. FM or the like is used for this modulation. The output signal of the local oscillator 10 is input to the transmission amplifier 15, and the output of the transmission amplifier 15 is input to the third terminal of the high-frequency signal changeover switch via the transmission filter 41. Here, the transmission filter is mainly for removing spurious components of the transmission amplifier. Then, the first terminal 17 and the third terminal 19 of the high-frequency signal changeover switch are set to be connected. A signal is output from the antenna terminal 12. The above is the transmission operation. The transceiver performs communication by switching between the above-described reception operation and transmission operation. The transceiver is configured by the above configuration.

[0007]

However, a problem of the above-mentioned conventional receiver is that it is not easy to achieve both the reception sensitivity and the anti-jamming characteristic. That is, in the above-described conventional example, a reception filter is configured before the reception amplifier. In this case, the reception signal from the antenna terminal is attenuated by the insertion loss of the reception filter. For example, when a SAW filter is used as a reception filter, about 5 dB of attenuation occurs. As a result, the S / N ratio of the received signal deteriorates, so that the sensitivity deteriorates. Further, the noise of the output of the receiving amplifier is converted by the mixer. At this time, in addition to the noise near the desired channel, the noise near the image frequency is converted to the same frequency, so that the S / N ratio of the mixer output deteriorates by 3 dB. As a result, the sensitivity is degraded by about 8 dB in total.

On the other hand, when the configuration is changed and a reception filter is arranged at the subsequent stage of the reception amplifier, the above-mentioned sensitivity degradation of 8 dB does not occur. However, since the receiving amplifier is located directly below the antenna terminal, the receiving amplifier is directly affected by the interference wave. In this configuration, an obstacle such as sensitivity degradation is likely to occur due to an interference wave input.
As described above, in the conventional receiver, if the reception filter is arranged in the front stage of the reception amplifier, the sensitivity is deteriorated, and if the reception filter is arranged in the rear stage, there is a problem that a sufficient interference wave characteristic cannot be obtained.

A problem with the above-mentioned conventional transceiver is that, in addition to the same problems as the above-described receiver, two transmission filters and a reception filter are required as high-frequency filters. That is, the receiving filter is required to have a large attenuation characteristic in an unnecessary frequency band in order to satisfy interference characteristics such as image interference and strong input interference. Therefore, the insertion loss in the pass band tends to increase. On the other hand, it is desirable for the transmission filter to minimize the insertion loss as much as possible in order to increase the transmission efficiency. The transmission filter is necessary for removing spurious components of the transmission amplifier. However, since this is mainly a harmonic component, it is not necessary to have a steep attenuation characteristic as compared with the reception filter. As described above, since the characteristics required for the reception filter and the transmission filter are different, it has been difficult to share the characteristics with one filter. The configuration of the reception filter and the transmission filter has been a constraint on miniaturization and cost reduction of the transceiver.

The present invention has been made to solve the above problems,
An object of the present invention is to provide a receiver that can achieve both reception sensitivity and anti-jam characteristics.

It is another object of the present invention to provide a transceiver capable of achieving both reception sensitivity and anti-jamming wave characteristics, and realizing miniaturization and low cost by sharing a reception filter and a transmission filter.

[0012]

According to the present invention, there is provided a high-frequency filter component including first and second high-frequency filter elements, wherein the first high-frequency filter element is connected to a stage preceding the high-frequency amplifier. The second high-frequency filter element is connected at a subsequent stage.

According to the present invention, the first high-frequency filter element removes the interference wave component, and the second high-frequency filter element removes the interference wave component and the noise component near the image frequency of the output of the high-frequency amplifier. Therefore, both the interference characteristic and the sensitivity characteristic can be achieved.

[0014]

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high frequency filter component including first and second high frequency filter elements, and two input / output terminals of the first high frequency filter element provided on the outer periphery of the high frequency filter element. And a third and a fourth external terminal respectively provided on the outer periphery of the high frequency filter component and connected to two input / output terminals of the second high frequency filter element. A high-frequency amplifier including an antenna terminal connected to the first external terminal, an input terminal connected to the second external terminal, and an output terminal connected to the third external terminal; 4 and a mixer for inputting and mixing the output signal of the external terminal and the signal of the local oscillator, and a demodulation circuit for performing a demodulation operation using the output signal of the mixer. Then, both the reception sensitivity characteristic and the interference wave characteristic can be achieved.

Also, a high-frequency filter component including first and second high-frequency filter elements, and a second high-frequency filter element provided on the outer periphery of the high-frequency filter element and connected to two input / output terminals of the first high-frequency filter element, respectively. First and second external terminals, third and fourth external terminals provided on the outer periphery of the high-frequency filter component and connected to two input / output terminals of the second high-frequency filter element, respectively, a receiving amplifier; A transmission amplifier, a high-frequency signal changeover switch, a mixer, a local oscillator, a demodulation circuit, and an antenna terminal, wherein the first external terminal and the antenna terminal are connected, the second external terminal and the high-frequency signal A first terminal of the changeover switch is connected, a second terminal of the high-frequency signal changeover switch is connected to an input terminal of the reception amplifier, and the reception amplifier An output terminal connected to the third external terminal, an output terminal of the fourth external terminal and an output terminal of the local oscillator connected to an input terminal of the mixer, an output terminal of the mixer connected to the demodulation circuit, The third terminal of the high-frequency signal changeover switch is connected to the output terminal of the transmission amplifier, the input terminal of the transmission amplifier is connected to the output terminal of the local oscillator, and the first terminal of the high-frequency signal changeover switch is connected during reception operation. The second terminal is switched so as to be connected, and at the time of transmission operation, the high-frequency signal switch is switched so that the first terminal and the third terminal are connected. The receiving sensitivity characteristic and the interference wave characteristic can be compatible, and the receiving filter and the transmitting filter can be used in common, so that the size and cost of the device can be reduced.

A high-frequency filter component containing first and second high-frequency filter elements, and first and second high-frequency filter elements provided on the outer periphery of the high-frequency filter element and connected to two input / output terminals of the first high-frequency filter element, respectively. A second external terminal, third and fourth external terminals provided on an outer periphery of the high frequency filter component and connected to two input / output terminals of the second high frequency filter element, a reception amplifier, and a transmission amplifier , A high-frequency signal changeover switch, and a first
, A second mixer, a first local oscillator, a second local oscillator, a demodulation circuit, and an antenna terminal,
The first external terminal is connected to the antenna terminal, and the second external terminal is connected to a first of the high-frequency signal changeover switches.
Is connected to the second terminal of the high-frequency signal changeover switch.
Is connected to the input terminal of the receiving amplifier, the output terminal of the receiving amplifier is connected to the third external terminal,
The fourth external terminal and the output terminal of the first local oscillator are connected to the input terminal of the first mixer, the output terminal of the first mixer is connected to the demodulation circuit, and the first local oscillator is connected to the first local oscillator. An output terminal of the oscillator and an output terminal of the second local oscillator are connected to an input terminal of the second mixer. An output terminal of the second mixer is connected to an input terminal of the transmission amplifier. An output terminal is connected to a third terminal of the high-frequency signal changeover switch. The first terminal and the second terminal of the high-frequency signal changeover switch are connected to each other during a reception operation. The signal switch is switched so that the first terminal and the third terminal of the signal switch are connected. Then, the receiving frequency and the transmitting frequency can be set arbitrarily, and the receiving operation and the transmitting operation can be switched at high speed.

Also, a high-frequency filter component containing first and second high-frequency filter elements, and a second high-frequency filter element provided on the outer periphery of the high-frequency filter element and connected to two input / output terminals of the first high-frequency filter element, respectively. First and second external terminals, third and fourth external terminals provided on the outer periphery of the high-frequency filter component and connected to two input / output terminals of the second high-frequency filter element, respectively, a receiving amplifier; A transmission amplifier, a high-frequency signal changeover switch, a mixer, a quadrature mixer, a 90-degree phase shifter, a first local oscillator, a second local oscillator, a demodulation circuit,
An antenna terminal, wherein the first external terminal is connected to the antenna terminal, the second external terminal is connected to a first terminal of the high-frequency signal changeover switch, and a second terminal of the high-frequency signal changeover switch is provided. Is connected to the input terminal of the receiving amplifier, the output terminal of the receiving amplifier is connected to the third external terminal, and the fourth external terminal and the output terminal of the first local oscillator are connected to the input terminal of the mixer. The output terminal of the mixer is connected to the demodulation circuit, the output terminal of the first local oscillator and the output terminal of the second local oscillator are connected to the input terminal of the quadrature mixer, Are connected to the input terminals of the 90-degree phase shifter, the output terminals of the 90-degree phase shifter are connected to the input terminals of the transmission amplifier, and the output of the transmission amplifier is And a third terminal of the high-frequency signal changeover switch is connected. The first terminal and the second terminal of the high-frequency signal changeover switch are connected during a reception operation, and the high-frequency signal is changed during a transmission operation. The switch is switched so that the first terminal and the third terminal of the switch are connected. Then, it is possible to increase the removal amount of the spurious component of the transmission signal.

Further, a second local oscillation frequency signal is generated by dividing the output of the first local oscillator by a frequency divider. Then, the oscillator can be simplified, and the size and cost of the device can be reduced.

Further, a third high-frequency filter element inserted in the front stage of the transmission amplifier and incorporated in the same high-frequency filter component as the first and second high-frequency filter elements is provided. Then, it is possible to increase the removal amount of the spurious component of the transmission signal.

The high frequency filter element is a surface acoustic wave filter formed on the same piezoelectric material substrate. Then, the high-frequency filter can be significantly reduced in size.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a block diagram showing a configuration of an embodiment of a receiver according to the present invention. In FIG. 1, 1 is a first high-frequency filter element, 2 is a second high-frequency filter element, 3 is a high-frequency filter component, 4 is a first external terminal, 5 is a second external terminal, and 6 is a third external terminal. Terminal, 7
Is a fourth external terminal, 8 is a high-frequency amplifier, 9 is a mixer, 1
0 is a local oscillator, 11 is a demodulation circuit, 12 is an antenna terminal, and 13 is an intermediate frequency filter.

The high frequency signal input to the antenna terminal 12 is input to a first external terminal provided on the high frequency filter component 3. The first external terminal is a high frequency filter component 3
Is connected to one of the input / output terminals of a first high-frequency filter element 1 incorporated therein, and the first high-frequency filter element 1 removes a part of an image frequency component and other interference wave components from the high-frequency signal. Are output from a second external terminal 5 connected to the other input / output terminal of the first high-frequency filter element 1. The output of the external terminal 5 is amplified by the high frequency up 8 and input to the third external terminal 6 provided on the high frequency filter component 3. The third external terminal 6 is connected to one input / output terminal of the second high-frequency filter element 2 built in the high-frequency filter component 3, and the second high-frequency filter element 2 causes the image frequency component and other interference waves to be generated. The component is further removed, and output from the fourth external terminal 7 connected to the other input / output terminal of the second high-frequency filter element 2. Then, the output of the fourth external terminal 7 and the output of the local oscillator 10 are mixed by the mixer 9 and converted into an intermediate frequency signal.
The channel of the intermediate frequency signal is selected by an intermediate frequency filter, and the demodulation circuit 11 performs a demodulation operation.

The present embodiment is characterized in that the first high-frequency filter element 1 and the second high-frequency filter element 2 are connected before and after the high-frequency amplifier 8. First, the role of the first high-frequency filter element 1 is to attenuate unnecessary components so that a large interference wave signal is not input to the high-frequency amplifier 8. For example, 30d for the interference wave frequency component
It is necessary to obtain the amount of attenuation of B.

On the other hand, the role of the second high-frequency filter element 2 is to attenuate components near the image frequency in the input signal to the mixer 9. Since the image frequency component is also attenuated by the first high-frequency filter element 1, it is sufficient that the required amount of attenuation is obtained in combination with the second high-frequency filter element 2. As the attenuation of 30 dB, a total attenuation of 60 dB can be obtained. Considering securing the interference characteristics as a receiver, a large amount of attenuation is required for image frequency components,
As long as no distortion occurs in the high-frequency amplifier 8 with respect to other interference wave frequency components, the required attenuation is relatively small.

By the way, if there is a loss before the high-frequency amplifier, the S / N ratio of the received signal is deteriorated and the sensitivity is deteriorated.
Therefore, it is desirable to minimize the loss at the stage preceding the high-frequency amplifier. That is, it is necessary to reduce the loss of the first high-frequency filter element 1. As described above, the attenuation of the first high-frequency filter element 1 provided before the high-frequency amplifier 8 may be relatively small, so that the loss in the pass band can be reduced. However, the image frequency component is attenuated further by the second high frequency filter element 2 because the first high frequency filter element 1 alone does not provide enough attenuation of the image frequency component. Since the deterioration of the S / N ratio due to the second high-frequency filter element 2 provided at the subsequent stage of the high-frequency amplifier 8 is reduced, the influence on the sensitivity deterioration is small.

Further, by providing the second high-frequency filter element 2 which attenuates the image frequency component at the subsequent stage of the receiving amplifier 8, the noise component of the image frequency generated by the high-frequency amplifier 8 can be removed. This allows the second
The sensitivity of about 3 dB is improved as compared with the case where the high frequency filter element 2 is not provided. Assuming that the loss in the pass band of each of the first and second high-frequency filter elements is 2.5 dB, the configuration of the present embodiment is about 5 dB less than the case where the two filters are arranged in front of the high-frequency amplifier 8. .5dB
Sensitivity can be improved. In addition, since the first high-frequency filter element 1 can secure a necessary amount of attenuation for the interfering wave, it is possible to achieve both the sensitivity characteristic and the interfering wave characteristic.

In this embodiment, the first high-frequency filter element 1
And the second high-frequency filter element 2 are built in the high-frequency filter component 3, and their input / output terminals are the first and second.
It is connected to the second, third and fourth external terminals 4, 5, 6, 7. Therefore, the high-frequency filter can be made small, and the size of the device can be reduced.

(Embodiment 2) FIG. 2 is a block diagram showing the configuration of a transceiver according to a second embodiment of the present invention. FIG.
, 14 is a receiving amplifier, 15 is a transmitting amplifier, 16
Is a high-frequency signal switch, 17 is a first terminal of the high-frequency signal switch, 18 is a second terminal of the high-frequency signal switch, 19 is a third terminal of the high-frequency signal switch, and 20 is a modulation circuit. The same components as those in FIG. 1 are denoted by the same reference numerals. The feature of this embodiment is that, in addition to the features of the receiver described in the first embodiment, the first high-frequency filter element 1 is also used as a transmission filter.

The present embodiment has a configuration of a transceiver that switches between a receiving operation and a transmitting operation. In FIG. 2, an external terminal 5 provided on the outer periphery of the high frequency filter component 3 is connected to a first terminal 17 of a high frequency signal changeover switch 16. The second terminal 1 of the high-frequency signal changeover switch 16
8 is connected to the input terminal of the receiving amplifier 14. The third terminal 19 of the high-frequency signal changeover switch 16 is connected to the output terminal of the transmission amplifier 15. During a receiving operation, the high-frequency signal changeover switch 16 is switched so that the first terminal 17 and the second terminal 18 are connected. During a transmitting operation, the first terminal 17 and the third terminal 19 are switched.
Are connected to switch the high frequency signal changeover switch 16. Therefore, the first high-frequency filter element 1 functions as a reception filter during a reception operation, and functions as a transmission filter during a transmission operation. Here, the role of the transmission filter is to remove spurious components included in the transmission signal. Since the spurious component is mainly a harmonic component, the transmission filter does not need a steep attenuation characteristic as compared with the reception filter, and the amount of attenuation may be relatively small. This is, for example, an attenuation of 30 dB. Rather, it is required that the transmission loss in the transmission frequency range be small. The fact that the loss in the pass band is required to be small is the same as the role of the first high-frequency filter element 1 during the receiving operation. Therefore, by using the first high-frequency filter element 1 also as a transmission filter, a high-frequency filter can be shared for transmission and reception. Since there is no need to newly provide a filter for transmission, the size and cost of the device can be reduced.

The modulation of the transmission signal can be obtained by modulating the output signal of the local oscillator 10 by the modulation circuit 20.

(Embodiment 3) FIG. 3 is a block diagram showing a configuration of a third embodiment of the transceiver according to the present invention.

In FIG. 2, reference numeral 21 denotes a first mixer;
Is a second mixer, 23 is a first local oscillator, and 24 is a second local oscillator.
Is a local oscillator. The same components as those in FIGS. 1 and 2 are denoted by the same reference numerals.

The feature of this embodiment lies in a method of generating a transmission signal. In this embodiment, in addition to the first local oscillator 23,
A second local oscillator 24 is provided. Further, a second mixer 22 is provided in addition to the first mixer 21. The transmission signal is the output of the first local oscillator 23 and the second local oscillator 2
4 is input to the second mixer 22 and frequency-converted to generate the output. Here, if the frequency of the second local oscillator 24 is selected to be the same as the intermediate frequency frequency of the receiving operation, it is not necessary to change the frequency of the first local oscillator 23 by switching between transmission and reception. Therefore, transmission and reception can be switched at high speed. Second mixer 2 during transmission
2 generates spurious noise, which can be attenuated by the first high-frequency filter element 1.

(Embodiment 4) FIG. 4 is a block diagram showing a configuration of a transceiver according to a fourth embodiment of the present invention. FIG.
In the above, 30 is a quadrature mixer, and 31 is a 90 ° phase shifter. The same components as those in FIGS. 1, 2 and 3 are denoted by the same reference numerals.

The feature of this embodiment resides in that the transmission signal is generated by the quadrature mixer 30 and the 90 ° phase shifter 31. The quadrature mixer and the 90 ° phase shift combiner constitute a sideband cancel mixer. Outputs of the first and second local oscillators 23 and 24 are input to a quadrature mixer 30, and two signals orthogonal to each other are obtained as outputs. By combining the two outputs of the quadrature mixer 30 with a phase difference of 90 °, one of the two sidebands obtained by mixing can be canceled. As a result, the spurious level generated by the mixing operation can be reduced, so that the attenuation of the first high-frequency filter element 1 can be reduced. Then, it becomes possible to design to further reduce the transmission loss in the transmission band.

It should be noted that a cancellation ratio of usually 20 to 30 dB can be obtained by the above-mentioned sideband cancellation mixer.

(Embodiment 5) FIG. 5 is a block diagram showing the configuration of a fifth embodiment of the transceiver according to the present invention. FIG.
In the above, 32 is a frequency divider. The same components as in FIGS. 1, 2, 3 and 4 are denoted by the same reference numerals.

This embodiment is characterized in that the third or fourth embodiment is used.
Is that a signal having a frequency corresponding to the output of the second local oscillator is generated by using a frequency divider instead of the second local oscillator used in (1).

The output of the local oscillator 10 is input to a frequency divider 32 to perform a predetermined frequency division. The output of the frequency divider 32 and the output of the local oscillator 10 are input to the quadrature mixer 30.

Since the second local oscillator can be omitted by using the frequency divider 32, the size and cost of the device can be reduced.

In this embodiment, the transmission signal is generated according to the fourth embodiment.
Although a sideband canceling mixer including a quadrature mixer and a 90 ° phase shifter similar to that of the third embodiment is used, a mixer similar to that of the third embodiment may be used.

Although the output signal of the frequency divider 32 contains spurious components such as harmonics, these unnecessary components can be removed by the first high-frequency filter 1.

(Embodiment 6) FIG. 6 is a block diagram showing the configuration of a transceiver according to a sixth embodiment of the present invention. FIG.
, 33 is a third high-frequency filter element, 34 is a fifth external terminal, and 35 is a sixth external terminal. The same components as those in FIG. 1, FIG. 2, FIG. 3 or FIG. 4 are denoted by the same reference numerals. The feature of the present embodiment resides in that a third high-frequency filter element is connected before the transmission amplifier 15.

In FIG. 6, the third high-frequency filter element 33 is incorporated in the high-frequency filter component 3, and the input and output terminals are the fifth external terminal 34 and the sixth external terminal formed on the outer periphery of the high-frequency filter component 3, respectively. 35.
The fifth external terminal 34 is connected to the second mixer, and the sixth external terminal 35 is connected to the input terminal of the transmission amplifier 15. The role of the third filter element 33 is to remove spurs generated at the output of the frequency divider 32 or the output of the second mixer 22. By employing a configuration in which these spurious components are removed before the transmission amplifier 15, it is possible to reduce the loss of the transmission amplifier output due to the filter. That is, spurious components generated by the frequency divider 32 or the second mixer 22 are generated relatively near the transmission frequency. Therefore, a filter that removes this tends to have a large passing loss. This role is assigned to the third high frequency filter element 33. By doing so, the first high-frequency filter 1 need only attenuate mainly the harmonic components generated by the transmission amplifier 15, so that the passage loss can be reduced. And transmission amplifier 1
5 can be efficiently transmitted to the antenna terminal 12.

Also, in the configuration of the first, second, third, fourth or fifth embodiment, the first and second high frequency filter elements are formed as surface acoustic wave filters formed on the same piezoelectric material substrate. Can be reduced in size. Further, the surface acoustic wave filter can be produced by a process similar to a semiconductor process, and can realize a significant cost reduction.

Also, in the configuration of the sixth embodiment, the first, second and third high frequency filter elements are formed as surface acoustic wave filters formed on the same piezoelectric material substrate. Cost can be reduced.

[0048]

As apparent from the above description, the following effects can be obtained according to the receiver of the present invention.

First and second stages are provided before and after the high-frequency amplifier, respectively.
Since the high-frequency filter element and the second high-frequency filter element are connected to each other, it is possible to reduce the pass loss of the filter and remove the interference wave component and the noise component of the output of the high-frequency amplifier. Since the output signal is obtained by frequency division and the frequency division number of the variable frequency divider can be set instantaneously, both the reception sensitivity characteristic and the interference wave characteristic can be achieved. This has the effect.

Further, since the high-frequency filter component incorporating the first and second high-frequency filter elements is used, the size of the high-frequency filter can be reduced, and the size of the device can be reduced.

As is clear from the above description, according to the transceiver of the present invention, in addition to the above-described effects as the receiver,
The following effects are obtained.

Switching is performed by a high-frequency switch for transmission and reception, and the first high-frequency filter element 1 is used as the reception filter and the transmission filter, so that the high-frequency filter can be shared, so that the size and cost of the device can be reduced. There is an effect that can be.

Further, since the transmission signal is generated using the mixer, there is no need to change the frequency of the local oscillator, and the transmission and reception can be switched at a high speed.

Further, since the sideband cancel mixer is constituted by the quadrature mixer and the 90 ° phase shift combiner, the spurious level generated by the mixing operation can be reduced.
Since the attenuation of the high-frequency filter element can be reduced, there is an effect that it is possible to design a filter that further reduces the transmission loss in the transmission band.

Further, since a signal corresponding to the second local oscillator is generated by the frequency divider, the second local oscillator can be omitted, and the size and cost of the device can be reduced.

Since each high frequency filter element is a surface acoustic wave filter formed on the same piezoelectric material substrate,
There is an effect that the size and cost of the high-frequency filter component can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram of a receiver according to a first embodiment of the present invention.

FIG. 2 is a block diagram of a transceiver according to a second embodiment of the present invention.

FIG. 3 is a block diagram of a transceiver according to a third embodiment of the present invention.

FIG. 4 is a block diagram of a transceiver according to a fourth embodiment of the present invention.

FIG. 5 is a block diagram of a transceiver according to a fifth embodiment of the present invention.

FIG. 6 is a block diagram of a transceiver according to a sixth embodiment of the present invention.

FIG. 7 is a block diagram showing a configuration of a conventional transceiver.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st high frequency filter element 2 2nd high frequency filter element 3 high frequency filter components 4 1st external terminal 5 2nd external terminal 6 3rd external terminal 7 4th external terminal 8 High frequency amplifier 9 Mixer 10 Local oscillator DESCRIPTION OF SYMBOLS 12 Antenna terminal 14 Receiving amplifier 15 Transmitting amplifier 16 High frequency signal changeover switch 17 First terminal of high frequency signal changeover switch 18 Second terminal of high frequency signal changeover switch 19 Third terminal of high frequency signal changeover switch 20 First mixer 21 Second mixer 23 First local oscillator 24 Second local oscillator 30 Quadrature mixer 31 90 ° phase shifter 32 Frequency divider 33 Third high frequency filter element

Claims (8)

[Claims] 1. A high-frequency filter component including first and second high-frequency filter elements, and a second high-frequency filter element provided on an outer periphery of the high-frequency filter element and connected to two input / output terminals of the first high-frequency filter element. First and second external terminals, third and fourth external terminals provided on the outer periphery of the high-frequency filter component and connected to two input / output terminals of the second high-frequency filter element, respectively, A high-frequency amplifier having an antenna terminal connected to an external terminal, an input terminal connected to the second external terminal, and an output terminal connected to the third external terminal;
And a demodulation circuit that performs mixing by inputting the output signal of the external terminal and the signal of the local oscillator and performs a demodulation operation using the output signal of the mixer. 2. A high-frequency filter component including first and second high-frequency filter elements, and a second high-frequency filter element provided on an outer periphery of the high-frequency filter element and connected to two input / output terminals of the first high-frequency filter element. First and second external terminals, third and fourth external terminals provided on the outer periphery of the high-frequency filter component and connected to two input / output terminals of the second high-frequency filter element, respectively, a receiving amplifier; A transmission amplifier, a high-frequency signal changeover switch, a mixer, a local oscillator, a demodulation circuit, and an antenna terminal, wherein the first external terminal and the antenna terminal are connected, the second external terminal and the high-frequency signal A first terminal of the changeover switch is connected, a second terminal of the high-frequency signal changeover switch is connected to an input terminal of the reception amplifier,
The output terminal of the receiving amplifier is connected to the third external terminal, the fourth external terminal and the output terminal of the local oscillator are connected to the input terminal of the mixer, and the output terminal of the mixer and the demodulation circuit are connected to each other. Connected, a third terminal of the high-frequency signal changeover switch is connected to an output terminal of a transmission amplifier, an input terminal of the transmission amplifier is connected to an output terminal of the local oscillator, and the third terminal of the high-frequency signal changeover switch is operated during a reception operation. A transceiver that is switched so that a first terminal and a second terminal are connected, and is switched so that a first terminal and a third terminal of the high-frequency signal switch are connected during a transmission operation. 3. A high-frequency filter component including first and second high-frequency filter elements, and a second high-frequency filter element provided on an outer periphery of the high-frequency filter element and connected to two input / output terminals of the first high-frequency filter element. First and second external terminals, third and fourth external terminals provided on the outer periphery of the high-frequency filter component and connected to two input / output terminals of the second high-frequency filter element, respectively, a receiving amplifier; A transmission amplifier, a high-frequency signal changeover switch, a first mixer, a second mixer, a first local oscillator,
A second local oscillator, a demodulation circuit, and an antenna terminal, wherein the first external terminal is connected to the antenna terminal, and the second external terminal is connected to a first terminal of the high-frequency signal changeover switch. A second terminal of the high-frequency signal switch and an input terminal of the receiving amplifier are connected;
An output terminal of the receiving amplifier is connected to the third external terminal, an output terminal of the fourth external terminal and an output terminal of the first local oscillator are connected to an input terminal of the first mixer,
An output terminal of the first mixer is connected to the demodulation circuit, and an output terminal of the first local oscillator and an output terminal of the second local oscillator are connected to an input terminal of the second mixer. The output terminal of the second mixer is connected to the input terminal of the transmission amplifier, the output terminal of the transmission amplifier is connected to the third terminal of the high-frequency signal changeover switch, and the first terminal of the high-frequency signal changeover switch is operated during reception operation. A transceiver that is switched so that a terminal and a second terminal are connected, and is switched so that a first terminal and a third terminal of the high-frequency signal switch are connected during a transmission operation. 4. A high-frequency filter component including first and second high-frequency filter elements, and a second high-frequency filter element provided on an outer periphery of the high-frequency filter element and connected to two input / output terminals of the first high-frequency filter element. First and second external terminals, third and fourth external terminals provided on the outer periphery of the high-frequency filter component and connected to two input / output terminals of the second high-frequency filter element, respectively, a receiving amplifier; A transmission amplifier, a high-frequency signal changeover switch, a mixer, a quadrature mixer, a 90-degree phase shifter, a first local oscillator, a second local oscillator, a demodulation circuit, and an antenna terminal; 1 external terminal and the antenna terminal are connected, the second external terminal is connected to a first terminal of the high-frequency signal changeover switch, and a second end of the high-frequency signal changeover switch is connected. And the input terminal of the receiving amplifier is connected, the output terminal of the receiving amplifier is connected to the third external terminal, and the fourth external terminal and the output terminal of the first local oscillator are connected to the input terminal of the mixer. Terminal, the output terminal of the mixer and the demodulation circuit are connected,
An output terminal of the first local oscillator and an output terminal of the second local oscillator are connected to an input terminal of the quadrature mixer,
Two output terminals of the quadrature mixer are connected to input terminals of the 90-degree phase shifter, output terminals of the 90-degree phase shifter are connected to input terminals of the transmission amplifier, and output terminals of the transmission amplifier. And the third of the high-frequency signal changeover switch
Are connected so that the first terminal and the second terminal of the high-frequency signal changeover switch are connected during the reception operation, and the first terminal and the third terminal of the high-frequency signal changeover switch are changed during the transmission operation. Transceiver that can be switched to connect the terminals. 5. The transceiver according to claim 3, wherein the output of the first local oscillator is divided by a frequency divider to generate a second local oscillation frequency signal. 6. The apparatus according to claim 2, further comprising a third high-frequency filter element inserted before the transmission amplifier and incorporated in the same high-frequency filter component as the first and second high-frequency filter elements. Transceiver as described. 7. The receiver according to claim 1, wherein the first and second high-frequency filter elements are surface acoustic wave filters formed on the same piezoelectric material substrate.
The transceiver according to any one of claims 4 and 5. 8. The transceiver according to claim 6, wherein the first, second and third high-frequency filter elements are surface acoustic wave filters formed on the same piezoelectric material substrate.