JPH0575495A - Mobile communication equipment - Google Patents

Abstract

PURPOSE:To provide a small sized mobile communication equipment with less number of component by implementing 2-way communication using plural frequency bands. CONSTITUTION:A 1st voltage controlled oscillator 112 controlled by a 1st phase locked loop (PLL) circuit 113 outputs an oscillation signal having a frequency twice the frequency used to frequency-convert a 2nd high frequency modulation signal frequency into a 1st intermediate frequency. The oscillation signal is inputted to a 2nd 1/2 frequency divider circuit 109 when the 2nd high frequency modulation signal is received and inputted to a 2nd 1/2 frequency divider circuit 110 when the 1st high frequency modulation signal is received respectively by a 2nd changeover circuit 111, and the oscillating signal becomes two signals whose phases differ by phi/2 thereat and they are inputted to a 1st mixer circuit 108.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile communication device such as a cordless phone or a car phone which performs bidirectional communication using a plurality of frequency bands.

[0002]

2. Description of the Related Art In a conventional mobile communication device for bidirectional communication, a voltage controlled oscillator for transmission / reception, a phase locked loop (hereinafter referred to as a PLL) is disclosed in Japanese Patent Laid-Open No. 61-220528. They shared circuits such as [Phase Locked Loop] to reduce circuit size and cost.

[0003]

However, the above mobile communication device can perform bidirectional communication only by using one frequency band. Therefore, in order to perform bidirectional communication using a plurality of frequency bands, a plurality of transmission / reception circuits are required, so that the number of parts increases and the circuit scale increases,
There was a problem that it became large.

An object of the present invention is to solve the above-mentioned problems of the prior art, and at least the above-mentioned plural frequency bands are the lowest frequency bands and an approximate N of the lowest frequency bands (N = 2, 4, 8, 16,
(2) In the case of being configured with a double frequency band, it is possible to perform bidirectional communication using the above-mentioned multiple frequency bands, and to provide a small-sized mobile communication device having a small number of parts. It is in.

[0005]

In order to achieve the above-mentioned object, in the present invention, at least the plurality of frequency bands are the lowest frequency bands and an approximate N of the lowest frequency bands (N = 2, 4, 4).
, 16) times the frequency band, the voltage controlled oscillator and the PLL circuit modulate the baseband signal into a high frequency modulation signal of each frequency band among the plurality of frequency bands. In the case of demodulating the high frequency modulated signals of the respective frequency bands of the plurality of frequency bands into the base band signals, respectively.

[0006]

The oscillating signal output from the voltage controlled oscillator is changed in frequency according to the frequency band of the high frequency modulation signal, or M (M = 2, 4, 8, 16,
…) Divide or use K (K = 2, 4, 8,
16, ...) It is multiplied and given to the modulator or demodulator. As a result, the voltage-controlled oscillator and the PLL circuit can be shared when the baseband signal is modulated into the high frequency modulation signals of the respective frequency bands of the plurality of frequency bands, and the voltage control oscillator and the PLL circuit can be commonly used. Can be shared when demodulating the high frequency modulated signals in the respective frequency bands into the base band signals. Therefore, according to the present invention, it is possible to perform bidirectional communication using transmission / reception signals of a plurality of frequency bands, and further, it is possible to reduce the size and cost by reducing the number of parts.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the present invention.

In the figure, 101 is a first transmitting / receiving antenna, 102 is a second transmitting / receiving antenna, 103 is a duplexer filter, 104 is a high frequency amplifier, 105 is a first switching circuit, and 106 is a first switching circuit. Bandpass filter, 10
7 is a second band pass filter, 108 is a first mixing circuit, 109 is a first 1/2 frequency dividing circuit, and 110 is a first 1
/ 4 frequency dividing circuit, 111 is a second switching circuit, and 112 is a first
Voltage controlled oscillator, 113 is a first PLL circuit, 114
Is a first isolator, 115 is a second isolator,
116 is a first high frequency power amplifier, 117 is a second high frequency power amplifier, 118 is a third band pass filter,
119 is a fourth band pass filter, 120 is a third switching circuit, 121 is a second mixing circuit, and 122 is a second 1/2.
Frequency divider circuit, 123 is a second 1/4 frequency divider circuit, 124 is a fourth switching circuit, 125 is a second voltage controlled oscillator, 126
Is a second PLL circuit, 127 is an intermediate frequency signal processing unit, 1
28 is a first baseband signal processing circuit, 129 is a switching signal generator, 130 is a second baseband signal processing circuit, 131 is a phase / amplitude correction data output section, 132 is a speaker, etc., 133 is an operating section, 134 Is a microphone, etc.

The operation of the mobile communication device for bidirectional communication using the transmission / reception signals of a plurality of frequency bands shown in FIG. 1 will be described. In the present embodiment, the first high frequency modulated signal in the first frequency band is transmitted and received via the first antenna 101, and is approximately twice as large as the first frequency band via the second antenna 102. The second high frequency modulated signal in the second high frequency band is transmitted and received. At this time, the operation unit 133 sets which of the first and second high frequency modulated signals is to be transmitted and received. This setting information is stored in the switching signal generator 129.
As a switching signal via the first switching circuit 105 and the second switching circuit.
Switching circuit 109, third switching circuit 120, fourth switching circuit 124, first PLL circuit 113, and second PL
It is applied to the L circuit 126 and controls each of the above circuits.

The operation when transmitting and receiving the second high frequency modulated signal via the second antenna 102 will be described. First, the operation at the time of reception will be described. Second antenna 10
A second high frequency modulation signal such as a quadrature-modulated voice signal and data signal inputted from 2 is amplified by a high frequency amplifier 104 via a duplexer filter 103, and is switched from a second switching circuit 105 by a switching signal. After the signal band is selected by the second band pass filter 107, it is input to the first mixing circuit 108.

On the other hand, from the first voltage controlled oscillator 112 controlled by the first PLL circuit 113, the frequency of the second high frequency modulated signal is doubled to the frequency at which the frequency should be converted into the first intermediate frequency signal. An oscillating signal having a frequency is output, and a switching signal causes the second switching circuit 111 to
The signals are input to the first ½ frequency divider circuit 109, where the two signals differ in phase by π / 2, and then input to the first mixing circuit 108.

As a result, the first mixing circuit 108 outputs two signals that are orthogonal to each other in the first intermediate frequency signal band, and is demodulated by the first baseband signal processing circuit 128 of the intermediate frequency signal processing unit 127. After being done, the speaker etc. 1
It is output as a voice signal and a data signal via 32.

Next, the operation during transmission will be described. A voice signal, a data signal, and the like input via the microphone or the like 134 are transferred to the second baseband signal processing circuit 13
With 0, the signals are input to the second mixing circuit 121 as two signals orthogonal to each other in the second intermediate frequency signal band.

On the other hand, from the second voltage controlled oscillator 125 controlled by the second PLL circuit 126, the frequency of the second intermediate frequency signal is doubled as the frequency to be frequency converted into the second high frequency modulated signal. An oscillating signal having a frequency is output, and a switching signal is output via the fourth switching circuit 124.
The signals are input to the second 1/2 frequency dividing circuit 122, where the two signals are different in phase by π / 2, and then input to the second mixing circuit 121.

In the second mixing circuit 121, if attention is paid only to the frequency relationship, the following signal processing is performed. That is, the second baseband signal processing circuit 130
From which two signals of sinφt and cosφt are input, and the second 1/2 divider circuit 122
From, two signals of sinωt and cosωt are input, and as output signals,
Cos (ω−φ) t of two signals sinωt × sinφt → cos (ω−φ) t− cos (ω + φ) t cosωt × cosφt → cos (ω−φ) t + cos (ω + φ) t One of the two signals sinωt × cosφt → sin (ω + φ) t + sin (ω−φ) t cosωt × sinφt → sin (ω + φ) t − sin (ω−φ) t is either sin (ω + φ) t. Is output.

That is, when the sum frequency component of the input signal is output from the second mixing circuit 121 as the second high frequency modulation signal, the unnecessary wave which is the difference frequency component of the input signal is canceled. , When outputting the difference frequency component of the input signal as the second high frequency modulated signal,
The unwanted wave that is the sum frequency component of the input signal is canceled.

However, the undesired wave signals synthesized as described above are canceled and attenuated by two signals respectively inputted from the second baseband signal processing circuit 130 and the second 1/2 frequency dividing circuit 122. The two signals have the same amplitude, and
It is when the phase difference is just π / 2. Therefore, the amplitudes of the two signals are equal and the phase difference is exactly π.
The phase / amplitude correction data is input from the phase / amplitude correction data output unit 131 to the second mixing circuit 121 so that the amount of attenuation of the unwanted wave signal is increased.

The second output from the second mixing circuit 121
The high-frequency modulated signal of the second high-frequency power amplifier 117, the second high-frequency power amplifier 117, the second high-frequency power amplifier 117, after the signal band is selected by the fourth band-pass filter 119 from the third switching circuit 120 by the switching signal.
Isolator 115 and duplexer filter 103
Is output from the second antenna 102 via.

Next, the first antenna 101
The operation when transmitting and receiving the high-frequency modulated signal is described. First, the operation at the time of reception will be described. A first high frequency modulated signal such as a quadrature modulated voice signal and data signal input from the first antenna 101 is amplified by a high frequency amplifier 104 via a duplexer filter 103, and a second signal is generated by a switching signal. The signal band is selected from the switching circuit 105 by the first bandpass filter 106, and then input to the first mixing circuit 108.

On the other hand, from the first voltage controlled oscillator 112 controlled by the first PLL circuit 113, the frequency of the second high frequency modulated signal is twice as high as the frequency to be frequency converted into the first intermediate frequency signal. An oscillating signal having a frequency, that is, an oscillating signal having a frequency four times as high as the frequency at which the frequency of the first high-frequency modulation signal should be frequency-converted into the first intermediate frequency signal is output, and the second switching circuit uses the switching signal. 11
1 is input to the first 1/4 frequency divider circuit 110,
Therefore, the two signals having the phases different by π / 2 are input to the first mixing circuit 108.

As a result, the two signals that are orthogonal to each other in the first intermediate frequency signal band are output from the first mixing circuit 108, and demodulated by the first baseband signal processing circuit 128 of the intermediate frequency signal processing unit 127. After being done, the speaker etc. 1
It is output as a voice signal and a data signal via 32.

Next, the operation during transmission will be described. A voice signal, a data signal, and the like input via the microphone or the like 134 are transferred to the second baseband signal processing circuit 13
With 0, the signals are input to the second mixing circuit 121 as two signals orthogonal to each other in the second intermediate frequency signal band.

On the other hand, from the second voltage controlled oscillator 125 controlled by the second PLL circuit 126, the frequency of the second intermediate frequency signal is doubled as the frequency to be frequency converted into the second high frequency modulated signal. An oscillating signal having a frequency, that is, an oscillating signal having a frequency four times as high as the frequency at which the frequency of the second intermediate frequency signal is to be frequency-converted into the first high-frequency modulation signal is output, and the fourth switching circuit uses the switching signal. 12
Is input to the second 1/4 frequency divider circuit 123 via
Therefore, the two signals having the phases different by π / 2 are input to the second mixing circuit 121. Even in this case, the second mixing circuit 121 performs the signal processing as described above, focusing only on the frequency relationship.

Also, the second baseband signal processing circuit 1
The phase / amplitude correction data is set so that the amplitudes of the two signals respectively input from the 30 and the second 1/4 frequency dividing circuit 123 are equal and the phase difference is exactly π / 2. From the output unit 131 to the second mixing circuit 1
The input signal is input to 21 to increase the attenuation amount of the unwanted wave signal.

The second output from the second mixing circuit 121
After the signal band of the high-frequency modulated signal is selected by the third band-pass filter 118 from the third switching circuit 120 by the switching signal, the first high-frequency power amplifier 116, the first high-frequency power amplifier 116,
Isolator 114 and duplexer filter 103
Is output from the first antenna 101 via the.

As described above, according to this embodiment, it is possible to perform bidirectional communication using the first frequency band and the second frequency band which is approximately twice the frequency band, and further In this case, the first voltage controlled oscillator 112 and the first PLL circuit 113 for performing signal processing of the respective frequency bands.
Since the second voltage controlled oscillator 125 and the second PLL circuit 126 are shared and can be used without changing the oscillation signal frequency bands of the first voltage controlled oscillator 112 and the second voltage controlled oscillator 125, Low score,
A smaller mobile communication device can be obtained.

Further, the high frequency amplifier 104, the first mixing circuit 108, the first 1/2 frequency dividing circuit 109, and the first 1/4.
Frequency dividing circuit 110, first voltage controlled oscillator 112, first high frequency power amplifier 116, second high frequency power amplifier 117, second mixing circuit 121, second 1/2 frequency dividing circuit 122, second The 1/4 frequency divider circuit 123, the second voltage controlled oscillator 125, etc. are replaced by GaAs (gallium arsenide) FETs.
By using the (field effect transistor), it is possible to obtain a mobile communication device which can be easily integrated into an IC and has excellent high frequency characteristics.

Further, the first mixing circuit 108 and the second mixing circuit 108
It is possible to provide a circuit having a good isolation characteristic between input signals by using a double balance structure of GaAsFET for the mixing circuit 121 of FIG.

In the above description, the bidirectional communication using the first frequency band and the second frequency band which is approximately twice the frequency band is performed. However, the second frequency band is the first frequency band. Even if the frequency band is approximately N (N = 4, 8, 16, 32, ...) times, the first 1/4 frequency divider circuit 110 and the second 1/4 frequency divider circuit are divided by 1 / 2N. (N = 4, 8, 16, 32, ...) By substituting the frequency dividing circuit, it is obvious that the same effect as above can be obtained.

FIG. 2 is a block diagram showing a second embodiment of the present invention. In the figure, 201 is a first π / 2 phase shifter and 202 is a second π / 2 phase shifter.
The same numbers as those in FIG. 1 are assigned to the same operations as those described in (1) and the description thereof will be omitted.

In FIG. 2, the operation in the case of performing bidirectional communication using the first frequency band and the second frequency band which is approximately twice the frequency band will be described. When receiving,
The first voltage controlled oscillator 112 controlled by the first PLL circuit 113 outputs an oscillation signal having a frequency at which the frequency of the second high frequency modulated signal should be frequency-converted into a first intermediate frequency signal. At the time of receiving the high frequency modulation signal of No. 2, by the switching signal via the second switching circuit 111,
The signals are input to the first π / 2 phase shifter 201, where they become two signals having a phase difference of π / 2, and then input to the first mixing circuit 108.

When receiving the first high frequency modulated signal,
The first switching signal is sent via the second switching circuit 111 by the switching signal.
Is input to the 1/2 frequency divider circuit 109, where the phase is π
After becoming two signals that differ by // 2, they are input to the first mixing circuit 108.

On the other hand, at the time of transmission, the second voltage controlled oscillator 125 controlled by the second PLL circuit 126.
Outputs an oscillation signal having a frequency at which the frequency of the second intermediate frequency signal should be frequency-converted into a second high-frequency modulation signal. During transmission of the second high-frequency modulation signal, the fourth switching circuit 124 is operated by the switching signal. Is input to the second π / 2 phase shifter 202, where it becomes two signals having a phase difference of π / 2, and then input to the second mixing circuit 121.

When transmitting the first high frequency modulated signal,
The second signal is sent via the fourth switching circuit 124 by the switching signal.
Is input to the 1/2 divider circuit 122, where the phase is π
After becoming two signals different by // 2, they are input to the second mixing circuit 121.

According to the present embodiment, in addition to the effect similar to that of FIG. 1, the oscillation signal frequency band from the first voltage controlled oscillator 112 and the second voltage controlled oscillator 125 and the first 1/1 /.
As the operating frequency band of the frequency-dividing circuit 109 and the second 1/2 frequency-dividing circuit 122, a frequency band half that of FIG. A good mobile communication device can be obtained.

In the above description, the bidirectional communication using the first frequency band and the second frequency band which is approximately twice the frequency band is performed. However, the second frequency band is the first frequency band. Even when the frequency band is approximately N (N = 4, 8, 16, 32, ...) times, the first 1/2 frequency dividing circuit 109 and the second 1/2 frequency dividing circuit 122 are It is obvious that the same effect as the above can be obtained by replacing with a 2N (N = 2, 4, 8, 16, ...) Dividing circuit.

FIG. 3 is a block diagram showing a third embodiment of the present invention. In the figure, 301 is a first 2 × multiplier, 302 is a first 4 × multiplier, 303 is a 2nd 2 × multiplier, 304 is a 2nd 4 × multiplier, etc. The same numbers as those in FIG. 1 are given to the same operations as those in FIG. 1, and the description thereof will be omitted.

In FIG. 3, an operation in the case of performing bidirectional communication using the first frequency band and the second frequency band which is approximately twice the frequency band will be described. When receiving,
The first voltage controlled oscillator 112 controlled by the first PLL circuit 113 outputs an oscillation signal having a frequency at which the frequency of the first high frequency modulation signal should be converted into the first intermediate frequency signal, When receiving the high frequency modulation signal of 2, the switching signal is input to the first doubler 301 through the second switching circuit 111 and is doubled. Then, it is input to the first 1/2 divider circuit 109, where
After becoming two signals whose phases are different by π / 2, they are input to the first mixing circuit 108.

When receiving the first high frequency modulation signal,
The switching signal is input to the first quadruple multiplier 302 via the second switching circuit 111 and is multiplied by four. And
The signals are input to the first ½ frequency divider circuit 109, where the two signals differ in phase by π / 2, and then input to the first mixing circuit 108.

On the other hand, at the time of transmission, the second voltage controlled oscillator 125 controlled by the second PLL circuit 126.
Outputs an oscillation signal having a frequency at which the frequency of the second intermediate frequency signal should be frequency-converted into the first high-frequency modulation signal, and when transmitting the second high-frequency modulation signal, the fourth switching circuit 124 is operated by the switching signal. Through the second doubler 30
It is input to 3 and is doubled. And the second 1/2
The signals are input to the frequency dividing circuit 122, where the two signals differ in phase by π / 2, and then input to the second mixing circuit 121.

When transmitting the first high frequency modulated signal,
The switching signal is input to the second quadruple multiplier 304 via the fourth switching circuit 124 and is multiplied by four. And
The signals are input to the second 1/2 frequency dividing circuit 122, where the two signals are different in phase by π / 2, and then input to the second mixing circuit 121.

According to the present embodiment, in addition to the effect similar to that of FIG. 1, the oscillation signal frequency band from the first voltage controlled oscillator 112 and the second voltage controlled oscillator 125 is 1 as compared with that of FIG. Since the frequency band of / 2 can be used, the oscillation characteristics are better and the frequency division operation is 1
Since only the 1/2 frequency dividing circuit is used, a mobile communication device having a small circuit scale can be obtained.

In the above description, the bidirectional communication is performed using the first frequency band and the second frequency band that is approximately twice the frequency band. However, the second frequency band is the first frequency band. Even when the frequency band is approximately N (N = 4, 8, 16, 32, ...) times, the first quadruple multiplier 302 and the second quadruple multiplier 304
It is clear that the same effect as above can be obtained by replacing N with N (N = 8, 16, 32, 64, ...) Multiplier.

FIG. 4 is a block diagram showing a fourth embodiment of the present invention. In the figure, components that perform the same operations as those shown in FIG. 3 are assigned the same numbers as those in FIG. 3 and their explanations are omitted.

In FIG. 4, an operation in the case of performing bidirectional communication using the first frequency band and the second frequency band which is approximately twice the frequency band will be described. When receiving,
When the second high frequency modulation signal is received from the first voltage controlled oscillator 112 controlled by the first PLL circuit 113, the frequency of the second high frequency modulation signal should be converted into the first intermediate frequency signal. When the first high-frequency modulation signal is received, the oscillation signal having a frequency at which the frequency of the first high-frequency modulation signal should be converted into the first intermediate-frequency signal is output. Then, the oscillation signal is input to the first doubler 301, is doubled, and then is input to the first 1/2 divider circuit 109, where two phases differing by π / 2. It becomes a signal and is then input to the first mixing circuit 108.

On the other hand, at the time of transmission, the second voltage controlled oscillator 125 controlled by the second PLL circuit 126.
From the above, an oscillation signal having a frequency at which the frequency of the second intermediate frequency signal should be frequency-converted into the second high frequency modulation signal is output at the time of transmitting the second high frequency modulation signal, and at the time of transmitting the first high frequency modulation signal, An oscillation signal having a frequency to be frequency-converted from the frequency of the second intermediate frequency signal to the first high frequency modulation signal is output. Then, the oscillation signal is input to the second doubler 302, doubled, and then input to the second 1/2 divider circuit 122, where the phase is π /
The two signals differ by two, and are then input to the second mixing circuit 121.

According to this embodiment, in addition to the effect similar to that of FIG. 3, the frequency band of the oscillation signal from the first voltage controlled oscillator 112 is the same as that of the received first or second high frequency modulated signal. Of the second voltage-controlled oscillator 125, the frequency band of the oscillating signal from the second voltage-controlled oscillator 125 is modulated to the first or second high-frequency modulated signal for transmitting the second intermediate-frequency signal. The oscillation frequency band of the first voltage-controlled oscillator 112 and the second voltage-controlled oscillator 125;
Band pass filter 106, second band pass filter 1
A mobile communication device with good usability can be obtained when the tracking characteristics of the 07 and the pass bands of the third band pass filter 118 and the fourth band pass filter 119 are secured.

In the above description, the bidirectional communication is performed using the first frequency band and the second frequency band that is approximately twice the frequency band. However, the second frequency band is the first frequency band. Even when the frequency band is approximately N (N = 4, 8, 16, 32, ...) times, it is clear that the same effect as above is obtained.

FIG. 5 is a block diagram showing a fifth embodiment of the present invention. In the figure, reference numeral 501 denotes a fifth switching circuit, and other elements that perform the same operations as those shown in FIG. 1 are given the same numbers as those in FIG. 1 and their explanations are omitted.

In FIG. 5, the operation in the case of performing bidirectional communication using the first frequency band and the second frequency band which is approximately twice the frequency band will be described. When receiving,
From the first voltage controlled oscillator 112 controlled by the first PLL circuit 113, the frequency of the frequency of the second high frequency modulated signal is converted into the frequency of the frequency of the frequency of the second intermediate frequency signal.
An oscillation signal having a doubled frequency is output, and the second switching circuit 11 is switched by the switching signal via the fifth switching circuit 501.
Input to 1.

On the other hand, at the time of transmission, the first voltage controlled oscillator 112 controlled by the first PLL circuit 113.
Outputs an oscillation signal having a frequency twice as high as the frequency at which the frequency of the second intermediate frequency signal is to be converted into the second high frequency modulation signal, and the switching signal causes the fifth switching circuit 501 to transmit the signal. It is input to the fourth switching circuit 124.

According to this embodiment, in addition to the same effect as that of FIG. 1, the first voltage controlled oscillator 112 and the first PLL are provided.
Since the circuit 113 can be shared during transmission and reception, a small-sized mobile communication device having a smaller number of parts can be obtained.

Also in the embodiment of FIGS. 2 to 4,
As in the present embodiment, the fifth switching circuit 501 is provided, and the first voltage controlled oscillator 112 and the first PLL circuit 11 are provided.
It is clear that the same effect as described above can be obtained by sharing 3 in transmitting and receiving.

FIG. 6 is a block diagram showing a sixth embodiment of the present invention. In the figure, 601 is a third PLL circuit, 602 is a third voltage controlled oscillator, and 603 is a third π.
/ 2 phase shifter, 604 is the third mixing circuit,
Those performing the same operations as those shown in FIG. 1 are assigned the same reference numerals as those in FIG. 1 and their explanations are omitted.

In FIG. 6, the received first or second high-frequency modulated signal is frequency-converted by the second mixing circuit 108 into a baseband modulated signal in the intermediate frequency band, and is input to the third mixing circuit 604. .. On the other hand, the third PLL circuit 6
An oscillation signal is output from the third voltage controlled oscillator 602 controlled by 01, and the third π / 2 phase shifter 60
3 into which the two signals differ in phase by π / 2, and then are input to the third mixing circuit 604.
As a result, the baseband modulated signal is demodulated by the oscillation signal output from the third voltage controlled oscillator 602 using one frequency band.

According to the present embodiment, in addition to the effect similar to that of FIG. 1, one frequency output from the third voltage controlled oscillator 602 when demodulating the received first or second high frequency modulated signal is obtained. Since only the oscillation signal of the band is shifted by π / 2,
In the demodulation signal processing, an oscillation signal with less phase error can be obtained, and a mobile communication device with higher performance can be obtained.

Also in the embodiment of FIGS. 2 to 5,
As in this embodiment, the third PLL circuit 601, the third voltage controlled oscillator 602, the third π / 2 phase shifter 603, the third
It is apparent that the same effect as described above can be obtained by performing the demodulation signal processing by using the mixing circuit 604 of FIG.

[0058]

According to the present invention, at least a plurality of frequency bands are the lowest frequency bands and the approximate N (N
, 2, 4, 8, 16, ...) times the frequency band, a plurality of frequency bands are used by sharing the voltage controlled oscillator and the PLL circuit used for modulation and demodulation in each frequency band. It is possible to obtain a smaller mobile communication device that is capable of bidirectional communication and has a small number of parts.

Further, a high frequency circuit section such as a high frequency amplifier, a mixing circuit, a frequency dividing circuit, a voltage controlled oscillator and a multiplier,
By using a GaAs FET, a mobile communication device that can be easily integrated into an IC and has excellent high frequency characteristics can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention.

FIG. 2 is a block diagram showing a second embodiment of the present invention.

FIG. 3 is a block diagram showing a third embodiment of the present invention.

FIG. 4 is a block diagram showing a fourth embodiment of the present invention.

FIG. 5 is a block diagram showing a fifth embodiment of the present invention.

FIG. 6 is a block diagram showing a sixth embodiment of the present invention.

[Explanation of symbols]

101 ... 1st transmission / reception antenna, 102 ... 2nd transmission / reception antenna, 103 ... Transmission / reception duplexer filter, 104 ...
High-frequency amplifier, 105 ... First switching circuit, 106 ... First
Band pass filter, 107 ... Second band pass filter, 108 ... First mixing circuit, 109 ... First 1/2 divider circuit, 110 ... First quarter divider circuit, 111 ... Second
Switching circuit, 112 ... First voltage controlled oscillator, 113 ...
First PLL circuit, 114 ... First isolator, 11
5 ... 2nd isolator, 116 ... 1st high frequency power amplifier, 117 ... 2nd high frequency power amplifier, 118 ...
Third band-pass filter, 119 ... Fourth band-pass filter, 120 ... Third switching circuit, 121 ... Second mixing circuit, 122 ... Second 1/2 divider circuit, 123 ... Second one
/ 4 frequency dividing circuit, 124 ... fourth switching circuit, 125 ... second
Voltage controlled oscillator, 126 ... Second PLL circuit, 127
... intermediate frequency signal processing unit, 128 ... first baseband signal processing circuit, 129 ... switching signal generator, 130 ... second baseband signal processing circuit, 131 ... phase / amplitude correction data output unit, 132 ... speaker, etc. 133 ... Operation unit,
134 ... Microphone etc.

Claims (10)

[Claims] 1. In order to perform bidirectional communication using a plurality of frequency bands, a baseband signal such as a voice signal or a data signal is transmitted at the time of transmission by using a first oscillation signal. It is obtained by receiving a desired high frequency modulation signal in the plurality of frequency bands at the time of reception by modulating the obtained high frequency modulation signal into a high frequency modulation signal in a desired frequency band In a mobile communication device that demodulates the high-frequency modulated signal into a baseband signal such as a voice signal or a data signal using a second oscillation signal, at least the plurality of frequency bands include a lowest frequency band and a lowest frequency band thereof. Of the frequency band of N (N = 2,4,8,16, ...) times, the first and second voltage controlled oscillators are provided, and the baseband signal is supplied to the plurality of frequency bands. Each frequency band in When each is modulated into a high frequency modulation signal, the first voltage controlled oscillator is shared, and the oscillation signal output from the first voltage controlled oscillator is used as the first oscillation signal, and / or the plurality of In the case of demodulating the high-frequency modulated signals in the respective frequency bands of the frequency bands into the baseband signal, the second voltage controlled oscillator is shared and the oscillation signal output from the second voltage controlled oscillator is shared. Is used as the second oscillation signal. 2. The mobile communication device according to claim 1, wherein
A phase-locked loop circuit or two phase-locked loop circuits for controlling the first and second voltage controlled oscillators is provided, and the baseband signal is provided in each of the plurality of frequency bands. In the case of respectively modulating into a high frequency modulation signal in a frequency band, the phase locked loop circuit is shared, and / or
A mobile communication device, wherein the phase-locked loop circuit is shared when demodulating a high-frequency modulated signal of each frequency band of the plurality of frequency bands into the baseband signal. 3. The mobile communication device according to claim 1, wherein the modulation performed at the time of transmission is quadrature modulation, the demodulation performed at the time of reception is quadrature demodulation, and a quadrature modulator and a quadrature demodulator are provided. When the baseband signal is quadrature-modulated into the high frequency modulation signals of the respective frequency bands of the plurality of frequency bands, the quadrature modulator is shared and / or each of the plurality of frequency bands is A mobile communication device, wherein the quadrature demodulator is shared when quadrature demodulating a high frequency modulated signal in a frequency band into the baseband signal. 4. The mobile communication device according to claim 1, wherein the modulation performed at the time of transmission is quadrature modulation, the demodulation performed at the time of reception is quadrature demodulation, and the first and second voltage controlled oscillators are: Each of them outputs an oscillation signal in the same frequency band as a frequency band twice as high as the highest frequency band in the plurality of frequency bands, and outputs the baseband signal to approximately 1 / M (M of the highest frequency band in the plurality of frequency bands. = 1, 2, 4, 8, 16,
...) When performing quadrature modulation on the high frequency modulation signal of the double frequency band, the oscillating signal from the first voltage controlled oscillator is frequency-divided by 2M to obtain two quadrature signals.
A quadrature modulator that quadrature modulates the baseband signal into the high frequency modulation signal by using the two orthogonal signals obtained by the first frequency dividing means as the first oscillation signal, and the plurality of frequencies. When orthogonally demodulating the high-frequency modulated signal in the frequency band approximately 1 / M times the highest frequency band in the band to the baseband signal, the oscillation signal from the second voltage controlled oscillator is divided by 2M and orthogonalized. Second to get two signals
And a quadrature demodulator for quadrature demodulating the high frequency modulated signal into the baseband signal by using the two orthogonal signals obtained by the second frequency dividing means as the second oscillation signal. And a mobile communication device. 5. The mobile communication device according to claim 1, wherein the modulation performed at the time of transmission is quadrature modulation, the demodulation performed at the time of reception is quadrature demodulation, and the first and second voltage controlled oscillators are Outputting an oscillation signal in the same frequency band as the highest frequency band in the plurality of frequency bands, respectively, and orthogonally modulating the baseband signal to a high frequency modulation signal in the highest frequency band in the plurality of frequency bands, The first phase shift means for obtaining two orthogonal signals by π / 2 phase shifting the oscillation signal from the voltage controlled oscillator of No. 1 and the baseband signal of the highest frequency band in the plurality of frequency bands. / M (M = 1,2,4,8,16, ...) When performing quadrature modulation on the high frequency modulation signal in the frequency band, the oscillation signal from the first voltage controlled oscillator is divided by 2M,
First frequency dividing means for obtaining two signals orthogonal to each other;
Of the two orthogonal ones obtained by the phase shifter or the first frequency dividing means of
A quadrature modulator that quadrature-modulates the baseband signal into the high-frequency modulation signal using two signals as the first oscillation signal, and a high-frequency modulation signal in the highest frequency band of the plurality of frequency bands as the baseband signal. When performing quadrature demodulation, the oscillation signal from the second voltage controlled oscillator is set to π /
Second phase shifting means for shifting two phases to obtain two orthogonal signals, and the outline of the highest frequency band of the plurality of frequency bands 1
When orthogonally demodulating a high frequency modulated signal in a frequency band of / M times to the baseband signal, the oscillation signal from the second voltage controlled oscillator is divided by 2M to obtain two orthogonal signals. The high frequency modulation signal is converted into the baseband signal by using the frequency division means and the two orthogonal signals obtained by the second phase shifter or the second frequency division means as the second oscillation signal. A quadrature demodulator for quadrature demodulation, and a mobile communication device. 6. The mobile communication device according to claim 1 or 2, wherein the modulation performed at the time of transmission is quadrature modulation, the demodulation performed at the time of reception is quadrature demodulation, and the first and second voltage controlled oscillators are: Each of them outputs an oscillation signal in the same frequency band as the lowest frequency band in the plurality of frequency bands, and when the baseband signal is orthogonally modulated to the high frequency modulation signal, the oscillation signal from the first voltage controlled oscillator. By K (K = 2, 4, 8, 16, ...) And outputs a signal in a frequency band twice as high as the frequency band of the high-frequency modulated signal; At the time of quadrature modulation to a high frequency modulation signal, the output signal from the first multiplication means is frequency-divided by two to obtain two signals which are orthogonal to each other, and the first frequency division means. Obtained, the two orthogonal signals A quadrature modulator that quadrature modulates the baseband signal into the high frequency modulation signal by using as a first oscillation signal, and the second voltage when quadrature demodulating the high frequency modulation signal into the baseband signal. Second multiplication means for multiplying the oscillation signal from the control oscillator by K to output a signal in a frequency band twice the frequency band of the high frequency modulation signal, and orthogonally demodulating the high frequency modulation signal into the baseband signal. At this time, the output signal from the second multiplication means is set to 2
Second frequency dividing means for dividing and obtaining two orthogonal signals, and the two orthogonal signals obtained by the second dividing means are used as the second oscillating signal to generate the high frequency wave. A quadrature demodulator for quadrature demodulating a modulated signal into the baseband signal, a mobile communication device. 7. The mobile communication device according to claim 1, wherein the modulation performed at the time of transmission is quadrature modulation, the demodulation performed at the time of reception is quadrature demodulation, and the first voltage controlled oscillator is the baseband. When the signal is quadrature-modulated to the high-frequency modulated signal, an oscillation signal in the same frequency band as the frequency band of the high-frequency modulated signal is output, and the second voltage-controlled oscillator converts the high-frequency modulated signal into the baseband signal. At the time of quadrature demodulation, while outputting an oscillation signal in the same frequency band as the frequency band of the high frequency modulation signal, at the time of quadrature modulating the baseband signal to the high frequency modulation signal, A first multiplication means for multiplying the oscillation signal by two and outputting the same; and an output signal from the first multiplication means for quadrature modulation from the baseband signal to the high frequency modulation signal. First frequency dividing means for obtaining two orthogonal signals by frequency division, and the two orthogonal signals obtained by the first frequency dividing means are used as the first oscillating signal to generate the baseband signal. A quadrature modulator for quadrature-modulating a signal into the high-frequency modulated signal; and a second quadrature output for oscillating the oscillation signal from the second voltage-controlled oscillator when the high-frequency modulated signal is orthogonally demodulated into the baseband signal. 2 multiplication means and a second division for obtaining two orthogonal signals by dividing the output signal from the second multiplication means by 2 when quadrature demodulating the high frequency modulated signal into the baseband signal. And a quadrature demodulator that quadrature demodulates the high-frequency modulated signal into the baseband signal by using the two orthogonal signals obtained by the second frequency dividing means as the second oscillation signal, A mobile communication device comprising: 8. The method of claim 1, 2, 3, 4, 5, 6 or 7.
In the mobile communication device described in (1), when the high frequency modulation signal is demodulated into the baseband signal by using the second oscillation signal at the time of reception, the oscillation signal output from the second voltage controlled oscillator. Is used as the second oscillation signal to frequency-convert the high frequency modulation signal into a baseband modulation signal, and then demodulates the baseband signal using the oscillation signal output from the third voltage controlled oscillator. A mobile communication device comprising: 9. The mobile communication device according to claim 4, 5, 6 or 7, wherein the phase difference between the two signals that are orthogonal to each other is always maintained at a difference of π / 2, and the amplitudes of the two signals are equal to each other. A mobile communication device comprising a correction means for performing correction so as to maintain the same amplitude. 10. Claims 1, 2, 3, 4, 5, 6, 7,
8. The mobile communication device according to 8 or 9, wherein the first and second voltage controlled oscillators are shared by one voltage controlled oscillator.