JPH09232993A - Radio telephone set - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a local oscillation circuit required for a portable telephone set having provision for the digital and analog systems by providing a generating means for a specific frequency signal, a modulation means and a reception local oscillation means oscillating a specific reception intermediate frequency signal. SOLUTION: In order to establish the portable telephone set having provision for the digital and analog systems, (a), a reception intermediate frequency fri is set to any transmission reception frequency difference, (b), a frequency of a reception local oscillation signal of a band corresponding to the frequency fri is made coincident with the frequency of the transmission local oscillation signal. Thus, a reference oscillator generating a reference signal is made up of a voltage controlled oscillator 1, a frequency variable PLL circuit 2, an oscillator 3, a fixed division PLL circuit 4, an oscillator 5, a fixed frequency divider circuit 6, and buffer amplifiers 7-9. A transmission local oscillation means and a reception local oscillation means to generate a transmission local oscillation signal through the operation of mixture of reference signals, changeover and synthesis or the like are made up of a low-pass filter 10, a mixer 11, a band-pass filter 12, a high frequency switch circuit 13, amplifiers 14, 15, and a high frequency distributer 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless telephone corresponding to a system having two discontinuous frequency bands, for example, both an 800 MHz band analog type mobile phone and a digital type mobile phone.

[0002]

2. Description of the Related Art FIG. 20 is a block diagram of a high frequency local oscillation circuit used in a conventional digital radio telephone disclosed in Japanese Patent Laid-Open No. 7-15240. In the figure, 5 is an oscillator for generating a second local oscillation signal for reception (RX), 11 is a mixer for generating a local oscillation signal for transmission, and 12 is a bandpass filter for removing unnecessary waves from the local oscillation signal for transmission. , 15 is an amplifier that makes the receiving first local oscillation signal an appropriate power, 20a is an oscillator that generates a high-frequency signal that is a source signal of the receiving first local oscillation signal and the transmitting local oscillation signal of the transmitter (TX), Reference numeral 51a is a modulator for directly modulating the transmission wave band frequency, 63 is a mixer for generating a reception second IF signal, 64 is a band filter in the reception first IF frequency band, and 65 is a reception first IF. A mixer which generates a signal, and 69 is an amplifier which amplifies the first IF signal for reception.

In this circuit, the first local oscillation signal for reception from the oscillator 20a and the second local oscillation signal for reception from the oscillator 5 are mixed by the mixer 11, and the local oscillation signal for transmission is passed through the bandpass filter 12. And the first local oscillation signal for reception are generated, and the transmission wave is directly modulated by the modulator 51a in the transmission frequency band.
Is being modulated by.

Further, FIG. 21 is a diagram of Japanese Unexamined Patent Publication No. 5-244032.
The dual-band radio telephone set disclosed in Japanese Patent Publication No.
This is a high-frequency local oscillation circuit compatible with both systems of 00 MHz band and 1.5 GHz band digital mobile phones. In the figure, 20b is an oscillator that generates a high-frequency signal that is a first local oscillation signal for reception, 20c is an oscillator that generates a high-frequency signal that is a local oscillation signal for transmission, 42 is an antenna device, 43 is a transmission / reception wave switch, 51b Is a modulator that indirectly modulates in the low frequency band, 53a is 800 MHz
Transmission system bandpass filter for band system, 53b is 1.5 GHz
Band system transmission wave bandpass filter, 54 a mixer, 55 a transmission system IF circuit, 61 a demodulator, and 65 a receiving first IF
A mixer for generating a signal, 67a is a received wave bandpass filter for 800 MHz band system, 67b is a received wave bandpass filter for 1.5 GHz band system, and 68 is a receiving system IF circuit.

In this circuit, the oscillation frequencies of the oscillators 20b and 20c are set in the middle of the two frequency bands, and the mixer 54,
The two up-and-down conversion characteristics of 65 are used to support two different transmission / reception frequency bands.

[0006]

The conventional high-frequency local oscillation circuit is constructed as described above, and in the case of FIG. 20, since the local oscillation frequencies of transmission and reception are the same, the frequencies for transmission and reception are different. In order to cope with two arbitrary transmission / reception frequency bands, it is necessary to provide two systems of this circuit, which causes a problem that the high frequency local oscillation circuit becomes large.

For example, taking an 800 MHz band analog type and digital type portable telephone as an example, the frequency configuration thereof is as shown in FIG. 7, and the transmitting and receiving frequency intervals are different between the analog type and the digital type. Therefore, FIG.
In order to support both systems with a circuit configuration such as 0, circuits such as oscillators 5 and 20a are required for each system independently.

Further, in the case of FIG. 21, in order to support two arbitrary transmission / reception frequency bands, an oscillator for generating a local oscillation signal for transmission and an oscillator for generating a local oscillation signal for reception are separately required, and a high frequency local oscillation is required. There are problems that the circuit becomes large and that the IF frequency is determined from the high frequency local oscillation circuit, so that general-purpose parts such as inexpensive filters that are commercially available cannot be used for the IF system circuit.

The present invention has been made to solve the above-mentioned problems, and is applied to two systems having an arbitrary frequency band, for example, both an analog mobile phone and a digital mobile phone in the 800 MHz band. The object is to obtain a corresponding small-sized and inexpensive wireless telephone.

[0010]

A radio telephone according to the present invention has a first band (a transmission band center frequency Ft1, a reception band center frequency Fr1, a bandwidth B1) and a second band.
When transmitting and receiving a radio signal of a band (a transmission band center frequency Ft2, a reception band center frequency Fr2, and a bandwidth B2), a reference oscillating means for generating a plurality of reference oscillation signals and a combination of the reference oscillation signals are used for transmission. As a local oscillation signal, a signal having a frequency of Ft1- (B1 / 2) to Ft1 + (B1 / 2) for the first band, and a signal having a frequency of Ft2- (B2 / 2) to Ft2 + for the second band. A local oscillator for transmission that generates a signal of (B2 / 2), a modulator that modulates the local oscillator signal for transmission with a baseband signal, and a reception intermediate frequency fri is | Ft1-Fr1 | or | Ft2-Fr2. The combination of the intermediate frequency receiving means for receiving and processing the signal that is | and the reference oscillation signal causes the reception intermediate frequency fr to be obtained as the local oscillation signal for reception. In the case of | Ft1−Fr1 |, signals having a frequency of Ft1− (B1 / 2) to Ft1 + (B1 / 2) for the first band and a frequency of Fr2 ± fri for the second band. − (B2 / 2) to Fr2 ± fri + (B
2/2) and the reception intermediate frequency fr is | Ft2-F
In the case of r2 |, the frequency is Fr1 ± fri− (B1 / 2) to Fr1 ± fri + (B for the first band.
1/2) signal and a local oscillating means for reception for generating a signal having a frequency of Ft2- (B2 / 2) to Ft2 + (B2 / 2) for the second band.

A combination of reference oscillation means for generating a plurality of reference oscillation signals, modulation means for modulating an oscillation signal having a frequency fti lower than the first and second transmission bands with a baseband signal, and the reference oscillation signal. Thus, as the local oscillation signal for transmission, the frequency is Ft1 ± fti− (B1 / 2) to Ft1 ± fti + (B for the first band.
1/2) signal and the second band, the frequency is Ft2 ± fti− (B2 / 2) to Ft2 ± fti + (B
2/2) local oscillation means for generating a signal, and a transmission signal for frequency-mixing the output signal from the modulating means and the local oscillation signal for transmission to convert them into radio signals in the first and second transmission bands. As a local oscillation signal for reception, a combination of a credit frequency conversion means, an intermediate frequency reception means for receiving and processing a signal whose reception intermediate frequency fr is | Ft1-Fr1 | or | Ft2-Fr2 | , If the reception intermediate frequency fr is | Ft1-Fr1 |, the signals with frequencies Ft1- (B1 / 2) to Ft1 + (B1 / 2) are sent to the first band and to the second band. On the other hand, the frequency is Fr2 ± fri− (B2 / 2) to Fr2 ± fri + (B
2/2) and the reception intermediate frequency fr is | Ft2-F
In the case of r2 |, the frequency is Fr1 ± fri− (B1 / 2) to Fr1 ± fri + (B for the first band.
1/2) signal and a local oscillating means for reception for generating a signal having a frequency of Ft2- (B2 / 2) to Ft2 + (B2 / 2) for the second band.

The reference oscillating means has a frequency variable width Δ1.
Is a variable frequency oscillator with max (B1, B2) ≦ Δ1 ≦ B1 + B2.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. Here, before entering the description with specific numerical examples, first, the system concept of the present invention using a modeled wireless telephone will be described.

First Embodiment of the Invention FIG. 1 is a modeled system block diagram of a wireless telephone showing one embodiment of the present invention, showing a case where a transmission signal is directly modulated in a transmission frequency band. In the figure, 100 is composed of at least one variable frequency oscillator, a voltage controlled oscillator, and one or more low frequency fixed oscillators,
Reference oscillating means for generating a plurality of reference oscillating signals, 101 is a transmitting local oscillating means for generating a transmitting local oscillating signal by operations such as mixing, switching and synthesizing the reference oscillating signals, 51
Reference numeral a denotes a modulator which directly modulates the local oscillation signal for transmission by a baseband signal to generate a transmission wave, and 102 also generates a local oscillation signal for reception by operations such as mixing, switching and synthesizing the reference oscillation signals. Local oscillating means for reception, 6
Reference numeral 5 is a mixer for mixing the received wave and the receiving local oscillation signal to generate a received first IF signal of a received intermediate frequency fri,
Reference numeral 103 is an intermediate frequency receiving means for receiving and processing the received first IF signal. Other symbols are the same as those in the conventional example. In such a radio telephone, two different bands, that is, the first band (transmission band center frequency F
t1, radio frequency of reception band center frequency Fr1, bandwidth B1, hereinafter referred to as "band 1") and second band (transmission band center frequency Ft2, reception band center frequency Fr2, bandwidth B2, hereinafter referred to as "band 2") Consider sending and receiving signals. The following items can be considered as basic requirements for simplifying the system configuration. The reception intermediate frequency fr of the reception system is common to both bands. That is, the intermediate frequency receiving means is shared by both bands. In order to simplify the internal structure of the transmitting and receiving local oscillation means, the frequencies of the oscillation signals are made common. As one implementation example of these requirements, for example, frequency setting that satisfies the following requirements can be considered. (a) The reception intermediate frequency fr is set to the transmission / reception frequency difference of any band. (b) Match the frequency of the local oscillation signal for reception with the frequency of the local oscillation signal for transmission in the band corresponding to the intermediate frequency fr.

FIG. 2 shows the signals (local transmission signal for transmission, reception first signal) of each part in the system of FIG. 1 in each of bands 1 and 2 set to realize the requests (a) and (b).
The frequency of the IF signal and the local oscillation signal for reception) is shown. In the figure, Case 1 shows the case where the reception intermediate frequency fri in the request (a) is the transmission / reception frequency difference of Band 1, and Case 2 shows the case where fri is the transmission / reception frequency difference of Band 2. The operation of such a wireless telephone will be described in case 1 of FIG. (Transmission system) Band 1: Frequency (Ft1- (B1 / 2) to Ft1 + (B1 /
The local oscillation signal for transmission in 2)) is directly modulated by the baseband signal to generate a transmission wave of band 1 (transmission band center frequency Ft1, bandwidth B1). Band 2: Frequency (Ft2- (B2 / 2) to Ft2 + (B2 /
The local oscillation signal for transmission of 2)) is directly modulated by the baseband signal to generate a transmission wave of band 2 (transmission band center frequency Ft2, bandwidth B2). (Reception system) Band 1: Frequency shown in Fig. 2 (Ft1- (B1 / 2) to Ft1 + (B1 /
2)) The received local oscillation signal for reception down-converts the reception wave of band 1 (reception band center frequency Fr1, bandwidth B1), and the reception intermediate frequency fr is | Ft1-F
Generate a received first IF signal of r1 |. Where | F
t1-Fr1 | represents the absolute value of Ft1-Fr1 and F
If t1 (frequency of local signal for reception)> Fr1 (in case of upper local), Ft1-Fr1, F
When t1 (frequency of local signal for reception) <Fr1 (lower local), Fr1−Ft1. Band 2: Frequency shown in Fig. 2 (Fr2 ± fri- (B2 / 2) ~ Fr2
± fri + (B2 / 2), where fri is shown in Band 1 above |
Ft1-Fr1 |), the reception local oscillation signal for reception causes the reception wave of band 2 (reception band center frequency Fr2,
The bandwidth B2) is down-converted, and the reception first IF signal having the reception intermediate frequency fr of | Ft1-Fr1 | is generated. Here, in the double sign ± of the frequency of the local signal for reception, + indicates an upper local case and − indicates a lower local case. As described above, the transmission / reception local transmission frequency in band 1 is set to a common frequency with Ft1- (B1 / 2) to Ft1 + (B1 / 2) (the above request (b)), and transmission local transmission in band 2 is performed. By setting the frequency to Ft2- (B2 / 2) to Ft2 + (B2 / 2) and the local frequency for reception to Fr2 ± fri- (B2 / 2) to Fr2 ± fri + (B2 / 2), the reception intermediate frequency fr Can be shared with | Ft1-Fr1 | in bands 1 and 2 (above requirement (a)). That is, the intermediate frequency receiving means can be shared.

The above discussion also applies to Case 2.

Embodiment 2 of the Invention FIG. 3 is a modeled system block diagram of a wireless telephone according to another embodiment of the present invention, showing a case where a transmission signal is indirectly modulated at a frequency lower than the transmission frequency band. The difference from the first embodiment in FIG. 1 is that in the case of FIG.
Is an oscillation signal having a frequency fti lower than the transmission band, is modulated by a baseband signal to generate a transmission IF signal having a frequency fti, and then the transmission IF signal and the local oscillation signal for transmission are mixed by a mixer 54, This is the point where the transmitted wave is generated. Others are the same as those in the first embodiment.

FIG. 4 shows the signals (local transmission signal for transmission, reception first signal) of the respective parts in the system of FIG. 3 in bands 1 and 2 set by the same idea as in the case of the first embodiment.
The frequency of the IF signal and the local oscillation signal for reception) is shown. Further, in the figure, cases 3 and 4 correspond to cases 1 and 2 in FIG. 2, respectively. The operation of such a wireless telephone will be described in case 3 of FIG. (Transmission system) Band 1: Frequency shown in Fig. 4 (Ft1 ± fti- (B1 / 2) ~ Ft1
(± fti + (B1 / 2)) local transmission signal for transmission and a transmission IF signal of frequency fti generated by modulating the transmission signal of frequency fti by the baseband signal are mixed, and band 1
Transmission wave (transmission band center frequency Ft1, bandwidth B
1) is generated. Here, + in the double sign ± of the frequency of the local transmission signal for transmission is a down-conversion characteristic of the mixer 54 (transmission wave frequency = local transmission frequency for transmission−transmission I).
F signal frequency) is used, and-indicates the case where the up-conversion characteristic of the mixer 54 (transmission wave frequency = transmission local oscillation frequency + transmission IF signal frequency) is used. Band 2: Frequency (Ft2 ± fti- (B2 / 2) ~ Ft2 shown in Fig. 4
± fti + (B2 / 2)) local transmission signal for transmission and a transmission IF signal of frequency fti generated by modulating the transmission signal of frequency fti by the baseband signal are mixed,
Transmission wave (center frequency Ft2 of transmission band, bandwidth B
2) is generated. Here, the double sign ± of the frequency of the local transmission signal for transmission is used in the same manner as described in Band 1. (Reception System) Band 1: The operation is the same as the operation in Band 1 of (Reception System) of Case 1 described in the first embodiment. Band 2: This is the same as the operation in band 2 of (reception system) of case 1 described in the first embodiment. As described above, in Band 1, the local transmission frequency for transmission is Ft1 ± fti-(B1 / 2) to Ft1 ± fti + (B1 / 2), and the local transmission frequency for reception is Ft1- (B1 / 2) to Ft1 + ( B1 / 2) and the local transmission frequency for transmission in band 2 is Ft2 ± fti-(B2 / 2)
~ Ft2 ± fti + (B2 / 2), local frequency for reception is Fr2 ± fr
By setting i- (B2 / 2) to Fr2 ± fri + (B2 / 2), the reception intermediate frequency fr is | Ft1-Fr1 | and bands 1, 2
Can be shared in. That is, the intermediate frequency receiving means can be shared.

The above discussion also applies to Case 4.

In the description of the first and second embodiments, the specific configurations of the reference oscillating means 100, the transmitting local oscillating means 101, and the receiving local oscillating means 102 are not touched.
Only the frequency setting of each part obtained by these means has been described. Specific configurations of these means will be described in the third and subsequent embodiments, but in the present invention, consideration has been given to satisfy the following basic requirements from the request for simplification of the configuration. (c) The number of variable frequency oscillators and fixed frequency oscillators constituting the reference oscillating means 100 is minimized. That is, the number of reference oscillation signals is suppressed to the necessary minimum. (d) The frequency variable width of the variable frequency oscillator should be as narrow as possible. That is, the required variable frequency signal of each part of the system is generated by a combination of the signal from the variable frequency oscillator and the signal from the fixed frequency oscillator. (As a constraint condition for the frequency variable width Δ1 of the variable frequency oscillator, the bandwidth B1 of band 1 and the bandwidth B2 of band 2 are used to set max (B1, B2) ≦ Δ1 ≦ B1 + B2 (max (B1, B2) Represents the larger one of B1 and B2), and a concrete configuration is realized under these conditions) (e) The frequency of the reference oscillation signal is the local oscillation means for transmission / reception. Set so that the number of operations such as mixing, switching, and synthesizing the reference oscillation signals is minimized.

As a specific system, a radio telephone corresponding to both the 800 MHz band analog system and the digital system whose frequency structure is shown in FIG. 7 will be described below. In the following specific example, for example, the analog frequency band corresponds to the band 1 and the digital frequency band corresponds to the band 2.

Third Embodiment of the Invention FIG. 5 is a system block diagram of a wireless telephone showing another embodiment of the present invention. The present embodiment is compatible with both the analog system and the digital system of the 800 MHz band shown in FIG. 7, and shows the case where the transmission signal is directly modulated in the transmission frequency band of both systems. In the figure, 1 is a high frequency voltage controlled oscillator whose oscillation frequency is variable, 2 is a frequency variable PLL circuit for stabilizing the oscillation frequency of this high frequency voltage controlled oscillator 1 and variably controlling the frequency within the oscillation frequency band. Oscillator for generating a fixed oscillation frequency, 4 is a fixed frequency dividing PLL circuit for stabilizing the oscillation frequency of the oscillator 3, 5 is an oscillator for generating a second local oscillation frequency for reception, and 6 is an oscillation frequency of the oscillator 5. A fixed frequency dividing PLL circuit for stabilizing the output of the voltage controlled oscillator 1, a buffer amplifier for stabilizing the output of the oscillator 3, a buffer amplifier for stabilizing the output of the oscillator 3, and a buffer amplifier for stabilizing the output of the oscillator 5.
Is a low-pass filter for attenuating the harmonic frequency components output from the oscillator 3, 13 is a high-frequency switch circuit for switching the frequency of the first local oscillation signal for reception, and 14 is an appropriate local oscillation signal for transmission. An amplifier for converting to electric power, 16 a high frequency distributor for dividing a signal into two systems, 41 a transmission / reception duplexer for transmitting a transmission wave to an antenna and receiving a reception wave from the antenna, 52 an amplifier for amplifying the transmission wave, and 62 a second IF A frequency bandpass filter, 66 is a low noise amplifier for amplifying the received wave, and 11 to 12, 15, 4
2, 51a, 61, 63 to 65 are exactly the same as the conventional circuit. Corresponding to the block diagram of FIG. 1, the reference oscillating means 100 of FIG. 1 is composed of 1 to 9 of FIG. 5, and the transmitting local oscillating means 101 and the receiving local oscillating means 102 of FIG. .About.16, and the intermediate frequency receiving means 1 of FIG.
03 will be comprised by 61-64 of FIG.
The “first local oscillation signal for reception” used in the description of the present embodiment and thereafter corresponds to the “local oscillation signal for reception” in FIGS.

FIG. 6 shows the setting of the local oscillation frequency for transmission / reception and the intermediate frequency of reception in this embodiment. Here, the reception intermediate frequency fr, which is the frequency of the reception first IF signal, is the difference between the transmission and reception frequency in the digital system of 130 MHz.
Is set to Further, the local oscillation frequency for reception is set to be upper local with respect to the frequency of the received wave. In order to obtain this frequency relationship, each oscillator in the reference oscillating means generates the following frequencies. Oscillator 3: Digital transmission / reception frequency difference (= 130
MHz) and analog transmission / reception frequency difference (= 55M
A signal of 75 MHz, which is the difference with the (Hz), is generated. Oscillator 5: Generates a signal of 129.55 MHz to obtain a second IF frequency for reception of 450 KHz. Voltage controlled oscillator 1: analog band (= 15 MH
z) and the digital system band (= 16 MHz) add up to 31 MHz, and the transmission bands of both systems are adjacent to each other to form a continuous band (see FIG. 7). Therefore, the frequency variable width is set to 31 MHz. . Since the frequency of the transmission wave does not match the frequency of the voltage controlled oscillator (If set to the same frequency, part of the transmission wave may sneak into the circuit system of the voltage controlled oscillator, causing deterioration of system performance such as deterioration of signal accuracy. ), 1000 to 10 higher than the local oscillation frequency for transmission by the frequency (= 75 MHz) of the oscillator 3
Generate a 31 MHz signal.

The radiotelephone configured as described above corresponds to the analog frequency band and the digital frequency band as follows.

In the case of supporting the analog system frequency, the voltage controlled oscillator 1 is 1000 to 1015 MHz, and the oscillator 3
Are oscillated at 75 MHz respectively, the signals of the voltage controlled oscillator 1 and the oscillator 3 are down-converted by the mixer 11 to obtain frequencies 925 to 940 MHz, and the signals are band-pass filtered.
The signal is distributed by the distributor 16 via 12 and supplied to the modulator 51a as a local oscillation signal for transmission via the amplifier 14. In addition, the signal generated by the voltage controlled oscillator 1 is supplied to the high frequency switch circuit 13
And select the frequency via the amplifier 15 and the frequency 1000 to 101.
5 MHz is supplied to the first mixer 65 as the upper local oscillation frequency (upper local) of the receiving first local oscillation signal. Further, the second local oscillation signal for reception is generated by the oscillator 5 and supplied to the mixer 63.

When the digital system frequency is supported, the voltage controlled oscillator 1 oscillates at 1015 to 1031 MHz and the oscillator 3 oscillates at 75 MHz, and the signals of the voltage controlled oscillator 1 and the oscillator 3 are down-converted by the mixer 11. Then, a frequency of 940 to 956 MHz is obtained, and the signal is distributed by the distributor 16 via the bandpass filter 12 and is supplied as a local oscillation signal for transmission to the modulator 51a via the amplifier 14 and is also distributed by the distributor 16. The other selected signal is selected by the high frequency switch circuit 13, and the first local oscillation signal for reception is amplified.
It is supplied to the mixer 65 via 15. The second local oscillation signal for reception is generated by the oscillator 5 as in the analog system and supplied to the mixer 63.

The third embodiment is configured as described above,
A high frequency voltage controlled oscillator with variable frequency
Since there is only one bandpass filter in the local oscillation circuit, it can be downsized, and it is relatively easy to form an LSI as a high-frequency local oscillation circuit, and the cost is low. Also, since there is only one mixer in the local oscillator circuit, transmission spurious waves are less likely to occur.

Fourth Embodiment of the Invention FIG. 8 is a system block diagram of a wireless telephone showing another embodiment of the present invention. This embodiment is similar to the third embodiment and is shown in FIG.
It corresponds to both the analog system and the digital system of the MHz band, and shows the case where the transmission signal is directly modulated in the transmission frequency band of both systems. In the figure,
1 to 16, 41 to 42, 51a to 52, 61 to 66 are exactly the same as those in FIG. Reference numeral 17 is a low-pass filter for attenuating harmonic frequency components output from the oscillator 5, 18 is a mixer for mixing high-frequency signals, and 19 is a band filter for removing unnecessary waves from the output signal of the mixer 18. It is a wave instrument. Corresponding to the block diagram of FIG. 1, the transmitting local oscillating means 101 and the receiving local oscillating means 102 are composed of 10 to 19 of FIG.

The transmission / reception local oscillation frequency and the reception intermediate frequency in this embodiment are set in the same manner as in the third embodiment.
It is as follows. In order to obtain this frequency relationship, each oscillator in the reference oscillating means generates the following frequencies. Oscillator 3: Generates a 75 MHz signal as in the third embodiment. Oscillator 5: Similar to the third embodiment, it generates a signal of 129.55 MHz. Voltage controlled oscillator 1: As in the third embodiment, the frequency variable width is 31 MHz. Since the frequencies of the transmission wave and the voltage controlled oscillator are not matched, a signal of 795.45 to 826.45 MHz which is lower than the local oscillation frequency for transmission by the frequency (= 129.55 MHz) of the oscillator 5 is generated.

In FIG. 8, when the analog system frequency is supported, the frequency 795.
The signal of 45 to 810.45 MHz and the signal of frequency 129.55 MHz generated by the oscillator 5 are up-converted by the mixer 11, distributed by the distributor 16 through the bandpass filter 12, and then the frequency by the amplifier 14. It is supplied to the modulator 51a as a local oscillation signal for transmission of 925 to 940 MHz. Further, the other signal distributed by the distributor 16 is up-converted with a signal of frequency 75 MHz generated by the oscillator 3 by the mixer 18 to obtain frequencies of 1000 to 1015 MHz, and the band pass filter 19 and the amplifier 15 are supplied. Then, it is supplied to the mixer 65 as an upper local oscillation signal for reception. At this time, the high frequency switch circuit
13 is connected. As the second local oscillation signal for reception, the signal generated by the oscillator 5 is used as it is in the mixer 63.
Supply to

When the digital system frequency is supported, the frequency 810.45 generated by the voltage controlled oscillator 1
The signal of 826.45 MHz and the signal of frequency 129.55 MHz generated by the oscillator 5 are up-converted by the mixer 11, distributed by the distributor 16 through the bandpass filter 12, and amplified.
The signal is supplied to the modulator 51a via 14 as a local oscillation signal for transmission having a frequency of 940 to 956 MHz. In addition, the distributor 1
The other signal distributed at 6 is supplied to the mixer 65 as a receiving upper local oscillation signal having a frequency of 940 to 956 MHz via the mixer 18, the bandpass filter 12, and the amplifier 15. At this time, the high-frequency switch circuit 13 is turned off and the signal generated by the oscillator 3 is cut off so that the mixer 18 functions as an amplifier. As the second local oscillation signal for reception, the signal generated by the oscillator 5 is directly supplied to the mixer 63 as in the analog system.

Since 75 MHz is not used in the digital system, the power source of the oscillator 3, the fixed frequency dividing PLL circuit 4, and the buffer amplifier 8 can be cut off, and the current consumption can be reduced.

In the fourth embodiment, the oscillation frequency of the voltage controlled oscillator 1 is 1054.55 to 1069.
55MHz, digital system 1069.55-108
Even if the frequency is 5.55 MHz, the same result as above can be obtained by using the down-conversion characteristic of the mixer 11. Further, even when the oscillation frequency of the oscillator 3 is set to 185 MHz, the down conversion characteristic of the mixer 18 is used in the analog system to convert the first local oscillation signal for reception into the lower local oscillation signal 7
By setting the frequency to 40 to 755 MHz, the same result as above can be obtained.

The fourth embodiment is configured as described above,
A high frequency voltage controlled oscillator with variable frequency
Since the number of bandpass filters in the local oscillation circuit is also two, miniaturization is possible, and it is relatively easy to form an LSI as a high-frequency local oscillation circuit and the cost is low. Further, in the digital system, the power supply to some circuits can be cut off, which is suitable for low current consumption.

Fifth Embodiment of the Invention FIG. 9 is a system block diagram of a wireless telephone showing another embodiment of the present invention. This embodiment is similar to the third embodiment and is shown in FIG.
It corresponds to both the analog system and the digital system of the MHz band, and shows the case where the transmission signal is directly modulated in the transmission frequency band of both systems. In the figure,
21 is a temperature-compensated crystal oscillator, 22 is a high-frequency multiplier that multiplies the signal generated by the temperature-compensated crystal oscillator 21 by 5,
1-2, 5-7, 9-19, 41-42, 51a-52, 61-66 are exactly the same as in FIG. Corresponding to the block diagram of FIG. 1, the reference oscillation means 100 of FIG.
~ 7, 9, 21, and 22.

The transmission / reception local oscillation frequency and the reception intermediate frequency in this embodiment are set in the same manner as in the third embodiment.
It is as follows. The circuit of FIG. 9 is basically the same as that of FIG. 8, except that the frequency of the temperature-compensated crystal oscillator 21 is set to 1 instead of the 75 MHz frequency signal generated by the oscillator 3 of FIG.
The frequency is 5 MHz, and the signal is multiplied by 5 in the high frequency multiplier 22, that is, used as 75 MHz.

Also in the fifth embodiment, the oscillation frequency of the voltage controlled oscillator 1 is 1054.55 to 1069.
55MHz, digital system 1069.55-108
Even if the frequency is 5.55 MHz, the same result as above can be obtained by using the down-conversion characteristic of the mixer 11.

The fifth embodiment is configured as described above,
Since the 75 MHz oscillator is not required, it can be miniaturized, and it is relatively easy to form an LSI as a high-frequency local oscillation circuit, and the cost is low.

In the other embodiments described in this specification, it is possible to generate 75 MHz by multiplying the temperature-compensated crystal oscillator as in the fifth embodiment.

Sixth Embodiment of the Invention FIG. 10 is a system block diagram of a wireless telephone showing another embodiment of the present invention. This embodiment is similar to the third embodiment and is shown in FIG.
It corresponds to both the analog system and the digital system of 0 MHz band, and shows the case where the transmission signal is directly modulated in the transmission frequency band of both systems. In the figure, 1-2, 5-7, 9, 11-16, 41-42, 51a-52, 6
1 to 66 are exactly the same as those in FIG. 5, 23 is a voltage controlled oscillator whose oscillation frequency is variable, 24 is a buffer amplifier for stabilizing the output of this voltage controlled oscillator 23, and 25 is a stable oscillation frequency of the voltage controlled oscillator 23. And a variable frequency division PLL circuit for variably controlling the frequency within the oscillation frequency band. Further, in association with the block diagram of FIG. 1, the reference oscillation means 100 of FIG.
Is composed of 1, 2, 5 to 7, 9, 23 to 25 in FIG. 10, and the transmitting local oscillating means 101 and the receiving local oscillating means 102 in FIG. 10 are composed of 11 to 17 in FIG. become.

The transmission / reception local oscillation frequency and the reception intermediate frequency in this embodiment are set in the same manner as in the third embodiment as shown in FIG.
It is as follows. In order to obtain this frequency relationship, each oscillator in the reference oscillating means generates the following frequencies. Oscillator 5: Similar to the third embodiment, it generates a signal of 129.55 MHz. Voltage-controlled oscillator 1: 795.45 as in the fourth embodiment.
Generate a signal at ~ 826.45 MHz. Voltage controlled oscillator 23: Generates a signal of 1000 to 1015 MHz which is a local oscillation frequency for reception in the analog system.

In FIG. 10, the frequency 79 generated by the voltage controlled oscillator 1 when the analog system frequency is supported.
The signal of 5.45 to 810.45 MHz and the signal of frequency 129.55 MHz generated by the oscillator 5 are up-converted by the mixer 11, distributed by the distributor 16 via the bandpass filter 12, and passed through the amplifier 14. And supplies it to the modulator 51a as a local oscillation signal for transmission having a frequency of 925 to 940 MHz. In addition, the frequency generated by the voltage controlled oscillator 23 is 1000-
A signal of 1015 MHz is selected by the high frequency switch circuit 13 and supplied to the mixer 65 as an upper local oscillation signal for reception via the amplifier 15. Further, as the second local oscillation signal for reception, the signal generated by the oscillator 5 is used as it is in the mixer 63.
Supply to

When the digital frequency is supported, the frequency 810.45-generated by the voltage controlled oscillator 1
The signal of 826.45 MHz and the signal of frequency 129.55 MHz generated by the oscillator 5 are up-converted by the mixer 11, distributed by the distributor 16 through the bandpass filter 12, and amplified.
The signal is supplied to the modulator 51a via 14 as a local oscillation signal for transmission having a frequency of 940 to 956 MHz. In addition, the distributor 1
The other signal distributed at 6 is the high-frequency switch circuit 1
Select with 3 and pass through amplifier 15 and frequency 940 ~ 956M
It is supplied to the mixer 65 as an upper local oscillation signal for reception of Hz. Further, as the second local oscillation signal for reception, the signal generated by the oscillator 5 is directly supplied to the mixer 63 as in the analog system.

In the digital system, the frequency is 1000 to 1
015 MHz is not necessary, the power source of the voltage controlled oscillator 23, the buffer amplifier 24, and the fixed frequency dividing PLL circuit 25 can be cut off, and the current consumption can be reduced.

Also in the sixth embodiment, the oscillation frequency of the voltage controlled oscillator 1 is 1054.55 to 1069.
55MHz, digital system 1069.55-108
Even if the frequency is 5.55 MHz, the same result as above can be obtained by using the down-conversion characteristic of the mixer 11.

The sixth embodiment is configured as described above,
It is relatively easy to form an LSI as a high-frequency local oscillation circuit, and the power supply to some circuits can be cut off in the digital system, which is suitable for low current consumption. further,
Since there is only one mixer in the local oscillator circuit, transmission spurious waves are less likely to occur.

Seventh Embodiment of the Invention FIG. 11 is a system block diagram of a wireless telephone showing another embodiment of the present invention. This embodiment is similar to the first embodiment and is shown in FIG.
It corresponds to both the analog system and the digital system of 0 MHz band, and shows the case where the transmission signal is directly modulated in the transmission frequency band of both systems. In the figure, 1 to 19, 41 to 42, 51a to 52, 61 to 66 are exactly the same as those in FIG. Reference numeral 26 is a high frequency distributor that divides the signal into two systems. Corresponding to the block diagram of FIG. 1, the reference oscillating means 100 of FIG. 1 is composed of 1 to 9 of FIG. 11, and the transmitting local oscillating means 101 and the receiving local oscillating means 102 of FIG. 〜19,26.

The transmission / reception local oscillation frequency and the reception intermediate frequency in this embodiment are set in the same manner as in the third embodiment as shown in FIG.
It is as follows. In order to obtain this frequency relationship, each oscillator in the reference oscillating means generates the following frequencies. Oscillator 5: Similar to the third embodiment, it generates a signal of 129.55 MHz. Oscillator 3: Instead of directly generating the frequency of 75 MHz described in the third embodiment, 12
To produce in combination with a 9.55MHz signal,
A signal of 55.45 MHz (= 129.55-75) is generated. Voltage controlled oscillator 1: As in the third embodiment, the frequency variable width is 31 MHz. Since the frequencies of the transmission wave and the voltage controlled oscillator are not matched, a signal of 1054.55-1085.55 MHz higher than the local oscillation frequency for transmission by the frequency (= 129.55 MHz) of the oscillator 5 is generated.

In FIG. 11, when the frequency corresponds to the analog system, the frequency 105 generated by the voltage controlled oscillator 1 is used.
4.55-1069.55MHz signal high frequency distributor
After distributing at 26, the frequency 12 generated at oscillator 5
The signal is down-converted by a mixer 11 with a signal of 9.55 MHz, distributed by a distributor 16 via a bandpass filter 12, and then transmitted via an amplifier 14 to a modulator 51a as a local oscillation signal for transmission having a frequency of 925 to 940 MHz. Supply. Further, the other signal distributed by the distributor 26 is down-converted by the mixer 18 with the signal of the frequency 54.55 MHz generated by the oscillator 3 to obtain the frequency 1000-1015 MHz, and this signal is band-pass filtered 19 After passing through, the signal is selected by the high frequency switch circuit 13 and supplied to the mixer 65 as an upper local oscillation signal for reception through the amplifier 15. Further, as the second local oscillation signal for reception, the signal generated by the oscillator 5 is directly supplied to the mixer 63.

When the digital system frequency is supported, the frequency 1069.55 generated by the voltage controlled oscillator 1 is generated.
The signal of -1085.55 MHz and the signal of frequency 129.55 MHz generated by the oscillator 5 are down-converted by the mixer 11, distributed by the distributor 16 through the bandpass filter 12, and then the frequency 940 by the amplifier 14. It is supplied to the modulator 51a as a local oscillation signal for transmission of 956 MHz. Further, the other signal distributed by the distributor 16 is selected by the high frequency switch circuit 13 and passed through the amplifier 15 to have frequencies 940 to 956.
It is supplied to the mixer 65 as an upper local oscillation signal for reception of MHz. As the second local oscillation signal for reception, the signal generated by the oscillator 5 is directly supplied to the mixer 63 as in the analog system.

Since 54.55 MHz is not used in the digital system, the oscillator 3, the fixed frequency dividing PLL circuit 4, the buffer amplifier 8 and the mixer 18 can be powered off, and the current consumption can be reduced.

The seventh embodiment is configured as described above,
Since it is composed of one voltage controlled oscillator and two bandpass filters, it is possible to miniaturize it and it is relatively easy to make an LSI as a high frequency local oscillation circuit. It is possible to cut off the power supply of and is suitable for low current consumption.

Eighth Embodiment of the Invention FIG. 12 is a system block diagram of a wireless telephone showing another embodiment of the present invention. This embodiment is similar to the third embodiment and is shown in FIG.
It corresponds to both the analog system and the digital system of 0 MHz band, and shows the case where the transmission signal is directly modulated in the transmission frequency band of both systems. In the figure, 1 to 11, 13 to 15, 17 to 19, 41 to 42, 51a to 52, 61 to 6
6 is exactly the same as FIG. 26 is a high-frequency divider that divides the signal into two, 27a is a bandpass filter that passes only signals in the local oscillation frequency band that support analog systems, and 27b is a bandpass filter that passes only signals in the local oscillation frequency band that support digital systems. , 28a is a high-frequency distributor connected to the bandpass filter 27a and dividing the signal into two systems, 28b is a high-frequency distributor connected to the bandpass filter 27b and dividing the signal into two systems, 29 is a distributor 28a
And a signal from the distributor 28b to combine the high-frequency synthesizer, 30 is a high-frequency synthesizer to combine the signals from the bandpass filter 19 and the distributor 28b, 31 is an input signal to the mixer 18 and an input signal to the high-frequency synthesizer 30. Is an interlocking high-frequency switch circuit that exclusively selects. Corresponding to the block diagram of FIG. 1, the reference oscillating means 100 of FIG. 1 is composed of 1 to 9 of FIG. 12, and the transmitting local oscillating means 101 and the receiving local oscillating means 102 of FIG. , 11, 13-15, 17-19, 26-
It will be composed of 30.

The transmission / reception local oscillation frequency and the reception intermediate frequency in the present embodiment are set in the same manner as in the third embodiment.
It is as follows. In order to obtain this frequency relationship, each oscillator in the reference oscillating means generates the following frequencies. Oscillator 5: Similar to the third embodiment, it generates a signal of 129.55 MHz. Oscillator 3: Generates a 75 MHz signal as in the third embodiment. Voltage controlled oscillator 1: Frequency band in analog system (= 1
5MHz) and digital frequency band (= 16MH
By partially overlapping z), the frequency variable width is set to 20.45 MHz which is narrower than 31 MHz which is a simple sum. The oscillation frequency is 1075 to 1090 MHz, which is higher than the local oscillation frequency for reception in analog by the frequency (= 75 MHz) of the oscillator 3, and the frequency of the oscillator 5 is higher than the local oscillation frequency for reception in digital (= 129.55 M).
Hz), higher by 1069.55 to 1085.55 MH
1069.55-1090 MH covering both z and
Generate a signal for z.

In FIG. 12, the frequency 107 generated by the voltage controlled oscillator 1 when the frequency corresponds to the analog system is used.
The signal of 5 to 1090 MHz and the signal of frequency 75 MHz generated by the oscillator 3 are down-converted by the mixer 11 to obtain frequencies of 1000 to 1015 MHz, distributed by the distributor 26, and further distributed through the bandpass filter 27a and the distributor 28a. Distributed at
The mixer 18 down-converts again the 75 MHz generated by the oscillator 3 to obtain a signal with a frequency of 925 to 940 MHz, and passes it through the bandpass filter 19, the synthesizer 30, and the amplifier 14 as a local oscillation signal for transmission. It is supplied to the modulator 51a. The other signal distributed by the distributor 28a is the combiner 2
It is supplied to the mixer 65 as a receiving upper local oscillation signal having a frequency of 1000 to 1015 MHz through the amplifier 9 and the amplifier 15. At this time, the high-frequency switch circuit 13 brings the signal from the oscillator 3 into the connected state, and the interlocking switch circuit 31 brings the input side of the mixer 18 into the connected state and the input side of the synthesizer 30 into the disconnected state. The signal generated by the oscillator 5 is directly supplied to the mixer 63 as the second local oscillation signal for reception.

When the digital system frequency is supported, the frequency 1069.55 generated by the voltage controlled oscillator 1 is generated.
The signal of -1085.55 MHz and the signal of frequency 129.55 MHz generated by the oscillator 5 are down-converted by the mixer 11 to obtain frequencies 940-956 MHz, distributed by the distributor 26 and further passed through the bandpass filter 27b. Distribute by distributor 28b, select by interlocking high frequency switch circuit 31, combiner
A local oscillation signal for transmission is supplied to the modulator 51a via the amplifier 30 and the amplifier 14. The other signal distributed by the distributor 28b passes through the combiner 29 and the amplifier 15 and has frequencies 940 to 940.
A mixer 65 is used as an upper local oscillation signal for reception at 956 MHz.
Supply to At this time, the high frequency switch circuit 13 causes the oscillator 5
The interlock switch circuit 31 disconnects the mixer 18 input side and connects the synthesizer 30 input side. As the second local oscillation signal for reception, the signal generated by the oscillator 5 is directly supplied to the mixer 63 as in the analog system.

Since 75 MHz is not used in the digital system, the power supply of the oscillator 3, the fixed frequency dividing PLL circuit 4, and the buffer amplifier 8 can be cut off, and the current consumption can be reduced.

In the eighth embodiment, as in the fifth embodiment, it is possible to generate 75 MHz by multiplying the temperature-compensated crystal oscillator.

Since the eighth embodiment is configured as described above, the oscillation frequency range of the voltage controlled oscillator 1 is narrower than that of the other embodiments, so that the electrical performance of the voltage controlled oscillator can be expected to be excellent. Further, in the digital system, the power supply to some circuits can be cut off, which is suitable for low current consumption.

Ninth Embodiment of the Invention FIG. 13 is a system block diagram of a wireless telephone showing another embodiment of the present invention. This embodiment corresponds to both the analog system and the digital system of the 800 MHz band shown in FIG. 7, and shows a case where the transmission signal is indirectly modulated at a low frequency and then frequency conversion is performed. In the figure,
15, 41 to 42, 52, 61 to 66 are exactly the same as those in FIG.
52 to 54 are the same as those in FIG. 31 is a voltage controlled oscillator 1
High-frequency distributor that divides the output of 3 into 3 systems, 53c is a mixer 54
A bandpass filter for attenuating the unnecessary wave generated in 1. and an amplifier 56 for amplifying the transmitted wave. Corresponding to the block diagram of FIG. 3, the reference oscillator 100 of FIG.
9, the transmitting local oscillating means 101 and the receiving local oscillating means 102 are comprised of 10 to 15 and 32 in FIG.

FIG. 14 shows the setting of the local oscillation frequency for transmission / reception and the intermediate frequency of reception in this embodiment. here,
The local oscillation frequency for transmission is set to be upper local to the frequency of the transmission wave. In order to obtain this frequency relationship, each oscillator in the reference oscillating means generates the following frequencies. Oscillator 3: Generates a 75 MHz signal as in the third embodiment. Oscillator 5: Similar to the third embodiment, it generates a signal of 129.55 MHz. Voltage controlled oscillator 1: 10 local oscillation frequency for transmission
A signal of 00 to 1031 MHz is generated.

In FIG. 13, when the frequency corresponds to the analog system, a frequency of 75 MHz is generated by the oscillator 3, the signal is modulated by the modulator 51b, and a frequency of 1000 to 1015 MHz is generated by the voltage controlled oscillator 1. Down-converting is performed by the mixer 54 to obtain a transmission modulation wave having a frequency of 925 to 940 MHz. In addition, the first local oscillation signal for reception is a signal generated by the voltage controlled oscillator 1 which is a high frequency switch circuit 13
And select the frequency via the amplifier 15 and the frequency 1000 to 101.
5 MHz is supplied to the mixer 65 as the upper side local oscillation frequency. The second local oscillation signal for reception is generated by the oscillator 5 and supplied to the mixer 63.

When the digital system frequency is supported, a frequency of 75 MHz is generated by the oscillator 3, the signal is modulated by the modulator 51b, and the mixer 54 is mixed with the frequency of 1015 to 1031 MHz generated by the voltage controlled oscillator 1. Is down-converted to obtain a transmission modulated wave having a frequency of 940 to 956 MHz. Further, as the first local oscillation signal for reception, signals from the voltage controlled oscillator 1 and the oscillator 3 are down-converted by the mixer 11 to obtain frequencies 940 to 956 MHz,
Select by high-frequency switch circuit 13 via bandpass filter 12,
It is supplied to the mixer 65 via the amplifier 15. In addition, the second for reception
The local oscillation signal is generated by the oscillator 5 and supplied to the mixer 63 as in the analog system.

In the ninth embodiment, as in the third embodiment, it is possible to generate 75 MHz by multiplying the temperature-compensated crystal oscillator.

The ninth embodiment is configured as described above,
Since one voltage controlled oscillator is used and one bandpass filter is also used, miniaturization is possible, and it is relatively easy to form an LSI as a high frequency local oscillation circuit and the cost is low.

Embodiment 10 of the Invention FIG. 15 is a system block diagram of a radio telephone showing another embodiment of the present invention. This embodiment is similar to the ninth embodiment and is shown in FIG.
It corresponds to both the analog system and digital system of the 00 MHz band, and shows the case where the transmission signal is indirectly modulated at a low frequency and the frequency is converted thereafter. In the figure, 1 to 15, 41 to 42, 51b to 54, 56, 61 to 6
6 is the same as FIG. 13, and 16 to 19 are the same as FIG.
Corresponding to the block diagram of FIG. 3, the local oscillator for transmission 101 and the local oscillator for reception 102 of FIG.
10 to 19 are included.

FIG. 16 shows the setting of the local oscillation frequency for transmission / reception and the intermediate frequency of reception in this embodiment. here,
The local oscillation frequency for transmission is set to be lower local to the frequency of the transmission wave. In order to obtain this frequency relationship, each oscillator in the reference oscillating means generates the following frequencies. Oscillator 3: Generates a 75 MHz signal as in the third embodiment. Oscillator 5: Similar to the third embodiment, it generates a signal of 129.55 MHz. Voltage controlled oscillator 1: The local oscillation frequency for transmission is 79
A signal of 5.45 to 826.45 MHz is generated.

In FIG. 15, when the frequency corresponds to the analog system, the oscillator 5 generates a frequency of 129.55 MHz, the signal is modulated by the modulator 51b, and the frequency of the voltage controlled oscillator 1 is 795.45. ~ 810.45MH
up-converted by mixer 54 with frequency 925
A transmission modulation wave of 940 MHz is obtained. Further, the other signal generated by the voltage controlled oscillator 1 and distributed by the distributor 16 is up-converted with the signal generated by the oscillator 5 by the mixer 11 to obtain frequencies 925 to 940 MHz and further by the oscillator 3. The signal generated at 75 MHz is up-converted by the mixer 18 and the frequency is 1000 to 1015 MHz.
After being obtained, it is supplied to the mixer 65 through the bandpass filter 19 and the amplifier 15 as an upper local oscillation signal for reception. At this time, the high frequency switch circuit 13 is in the connected state. The signal generated by the oscillator 5 is directly supplied to the mixer 63 as the second local oscillation signal for reception.

In the case of supporting the digital system frequency, the oscillator 5 generates a frequency of 129.55 MHz, the signal is modulated by the modulator 51b, and the voltage controlled oscillator 1 generates a frequency of 810.45-826. Frequency up to 940-956 with mixer 54 at 45 MHz
Obtain the transmitted modulated wave of MHz. Further, the other signal generated by the voltage controlled oscillator 1 and distributed by the distributor 16 is up-converted with the signal generated by the oscillator 5 by the mixer 11 to obtain frequencies 940 to 956 MHz, and the band pass filter is obtained. 12, mixer 18, bandpass filter 19, amplifier 15 and frequency 940
A mixer 65 is used as an upper local oscillation signal for reception at 956 MHz.
Supply to At this time, the high-frequency switch circuit 13 is turned off and the signal generated by the oscillator 3 is cut off so that the mixer 18 functions as an amplifier. Further, as the second local oscillation signal for reception, the signal generated by the oscillator 5 is directly supplied to the mixer 63 as in the analog system.

Since 75 MHz is not used in the digital system, the power supply of the oscillator 3, the fixed frequency dividing PLL circuit 4, and the buffer amplifier 8 can be cut off, and the current consumption can be reduced.

In the tenth embodiment, the oscillation frequency of the voltage controlled oscillator 1 is 1054.55 to 106 when the analog system is used.
9.55MHz, digital system 1069.55-1
Even if the frequency is 085.55 MHz, the same result as above can be obtained by utilizing the down-conversion characteristics of the mixers 11 and 54. Moreover, the oscillation frequency of the oscillator 3 is set to 185 MHz.
Also, by using the down conversion characteristic of the mixer 18 in the analog system and setting the first local oscillation signal for reception to the lower local oscillation signal 740 to 755 MHz, the same result as above can be obtained.

In the tenth embodiment, as in the third embodiment, it is possible to generate 75 MHz by multiplying the temperature-compensated crystal oscillator.

The tenth embodiment is constructed as described above, and is composed of one voltage controlled oscillator and two bandpass filters.
Therefore, it is possible to miniaturize, it is relatively easy to make an LSI as a high-frequency local oscillation circuit, and the power of some circuits can be cut off in the digital system, which is suitable for low current consumption. ing.

Embodiment 11 of the Invention FIG. 17 is a system block diagram of a radio telephone showing another embodiment of the present invention. This embodiment is similar to the ninth embodiment and is shown in FIG.
It corresponds to both the analog system and digital system of the 00 MHz band, and shows the case where the transmission signal is indirectly modulated at a low frequency and the frequency is converted thereafter. In the figure, 1-2, 5-7, 9, 11-15, 41-4
2, 51b to 54, 56, 61 to 66 are the same as those in FIG.
7, 23 to 25 are the same as in FIG. Corresponding to the block diagram of FIG. 3, the local oscillator for transmission 101 of FIG.
The local oscillator for reception 102 is constituted by 11 to 17 in FIG.

The transmission / reception local oscillation frequency and the reception intermediate frequency in this embodiment are set as shown in FIG. 16 as in the tenth embodiment. In order to obtain this frequency relationship, each oscillator in the reference oscillating means generates the following frequencies. Oscillator 5: Similar to the third embodiment, it generates a signal of 129.55 MHz. Voltage controlled oscillator 1: The local oscillation frequency for transmission is 79
A signal of 5.45 to 826.45 MHz is generated. Voltage controlled oscillator 23: 1000 to 1015 which is the local oscillation frequency for reception in the analog system as in the sixth embodiment.
Generate a MHz signal.

In FIG. 17, when the frequency corresponds to the analog system, the frequency 5129.55 MHz is generated by the oscillator 5, the signal is modulated by the modulator 51b, and the frequency 795.45 is generated by the voltage controlled oscillator 1. ~ 810.45MH
up-converted by mixer 54 with frequency 925
A transmission modulation wave of 940 MHz is obtained. Further, a signal having a frequency of 1000 to 1015 MHz generated by the voltage controlled oscillator 23 is selected by the high frequency switch circuit 13 and supplied to the mixer 65 as an upper local oscillation signal for reception. Further, as the second local oscillation signal for reception, the signal generated by the oscillator 5 is directly supplied to the mixer 63.

When the digital system frequency is supported, a frequency of 129.55 MHz is generated by the oscillator 5, the signal is modulated by the modulator 51b, and a frequency of 810.45- 826. Frequency up to 940-956 with mixer 54 at 45 MHz
Obtain the transmitted modulated wave of MHz. Further, the other signal generated by the voltage controlled oscillator 1 and distributed by the distributor 16 is up-converted with the signal generated by the oscillator 5 by the mixer 11 to obtain frequencies 940 to 956 MHz, and the band pass filter is obtained. The signal is selected by the high frequency switch circuit 13 via 12 and is supplied to the mixer 65 via the amplifier 15 as the upper local oscillation signal for reception. As the second local oscillation signal for reception, the signal generated by the oscillator 5 is used as it is in the analog system as it is in the mixer 63.
Supply to

In the digital system, the frequency is 1000 to 1
015 MHz is not necessary, the power source of the voltage controlled oscillator 23, the buffer amplifier 24, and the fixed frequency dividing PLL circuit 25 can be cut off, and the current consumption can be reduced.

Also in the eleventh embodiment, the oscillation frequency of the voltage controlled oscillator 1 is 1054.55 to 106 in the analog system.
9.55MHz, digital system 1069.55-1
Even if the frequency is 085.55 MHz, the same result as above can be obtained by utilizing the down-conversion characteristics of the mixers 11 and 54.

The eleventh embodiment is configured as described above, and it is relatively easy to form an LSI as a high-frequency local oscillation circuit, and the power supply to some circuits can be cut off in the digital system, resulting in low current consumption. Suitable for

Twelfth Embodiment of the Invention FIG. 18 is a system block diagram of a wireless telephone showing another embodiment of the present invention. This embodiment is similar to the ninth embodiment and is shown in FIG.
It corresponds to both the analog system and digital system of the 00 MHz band, and shows the case where the transmission signal is indirectly modulated at a low frequency and the frequency is converted thereafter. In the figure, 1 to 15, 32, 41 to 42, 51 to 54, 56, 61
66 are the same as in FIG. 13, and 17 to 19 are the same as in FIG. Corresponding to the block diagram of FIG. 3, the transmitting local oscillating means 101 and the receiving local oscillating means 102 are composed of 10 to 15, 17 to 19 and 32 of FIG.

FIG. 19 shows the setting of the local oscillation frequency for transmission / reception and the intermediate frequency of reception in this embodiment. here,
The local oscillation frequency for transmission is set to be upper local to the frequency of the transmission wave. In order to obtain this frequency relationship, each oscillator in the reference oscillating means generates the following frequencies. Oscillator 5: Similar to the third embodiment, it generates a signal of 129.55 MHz. Oscillator 3: Generates a 55.45 MHz signal as in the seventh embodiment. Voltage controlled oscillator 1: 10 local oscillation frequency for transmission
A signal of 54.55 to 1085.55 MHz is generated.

In FIG. 18, when the frequency corresponds to the analog system, the oscillator 5 generates the frequency 129.55 MHz, the signal is modulated by the modulator 51b, and the frequency 1054.55 generated by the voltage controlled oscillator 1 is generated. -1069.55
Frequency downconverted by mixer 54 with MHz
A transmission modulation wave of 5 to 940 MHz is obtained. Further, another signal generated by the voltage controlled oscillator 1 and distributed by the distributor 32 is down-converted by the mixer 18 with the signal of the frequency 54.55 MHz generated by the oscillator 3 to obtain a frequency of 1000.
-1015 MHz is obtained, and this signal is passed through the bandpass filter 19 and then selected by the high frequency switch circuit 13 to be supplied to the mixer 65 as an upper local oscillation signal for reception through the amplifier 15. Further, as the second local oscillation signal for reception, the signal generated by the oscillator 5 is directly supplied to the mixer 63.

When the digital system frequency is supported, the oscillator 5 generates a frequency of 129.55 MHz, the signal is modulated by the modulator 51b, and the voltage controlled oscillator 1 generates the frequencies of 1069.55 to 1085. 55MHz
And downconverted by mixer 54 and frequency 940-9
A 56 MHz transmitted modulated wave is obtained. Further, another signal generated by the voltage controlled oscillator 1 and distributed by the distributor 32 is down-converted by the mixer 11 and the signal generated by the oscillator 5 to obtain frequencies 940 to 956 MHz. After passing through the bandpass filter 12, high frequency switch circuit
Select at 13 and pass through amplifier 15 and frequency 940-956MH
It is supplied to the mixer 65 as an upper local oscillation signal for reception of z. As the second local oscillation signal for reception, the signal generated by the oscillator 5 is directly supplied to the mixer 63 as in the analog system.

Since 54.55 MHz is not used in the digital system, the oscillator 3, the fixed frequency dividing PLL circuit 4, the buffer amplifier 8 and the mixer 18 can be powered off, and the current consumption can be reduced.

The twelfth embodiment is constructed as described above, and is composed of one voltage-controlled oscillator and two bandpass filters.
Therefore, it is possible to miniaturize, it is relatively easy to make an LSI as a high-frequency local oscillation circuit, and it is possible to turn off the power of some circuits in the digital system.
Suitable for low current consumption.

By the way, in the above embodiments, all are 800
Although the explanation has been given by using the one corresponding to both the analog system and the digital system of the MHz band, it is not limited to this system, but can be applied to any other two different frequency bands by changing the oscillation frequency of the oscillator. Needless to say, it can also be used.

[0088]

Since the present invention is configured as described above, it achieves the object with two to three PLL circuits and one to two voltage controlled oscillators, and the circuit is easily configured and is small in size. The advantages are that the cost can be increased, the cost can be reduced, and the LSI can be relatively easily formed.

[Brief description of drawings]

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

FIG. 2 is an explanatory diagram of signal frequencies of various parts in the system according to the first embodiment of the present invention.

FIG. 3 is a modeled system block diagram showing a second embodiment of the present invention.

FIG. 4 is an explanatory diagram of signal frequencies of various parts in the system according to the second embodiment of the present invention.

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

FIG. 6 is an explanatory diagram of signal frequencies of various parts in the system according to the third embodiment of the present invention.

FIG. 7 is an explanatory diagram of a frequency configuration of an 800 MHz band analog type and digital type mobile phone used for explaining the embodiment of the invention.

FIG. 8 is a block diagram showing a fourth embodiment of the present invention.

FIG. 9 is a block diagram showing a fifth embodiment of the present invention.

FIG. 10 is a block diagram showing a sixth embodiment of the present invention.

FIG. 11 is a block diagram showing a seventh embodiment of the present invention.

FIG. 12 is a block diagram showing an eighth embodiment of the present invention.

FIG. 13 is a block diagram showing a ninth embodiment of the present invention.

FIG. 14 is an explanatory diagram of signal frequencies of various parts in the system according to the ninth embodiment of the present invention.

FIG. 15 is a block diagram showing a tenth embodiment of the present invention.

FIG. 16 is an explanatory diagram of signal frequencies of various parts in the system according to the tenth embodiment of the present invention.

FIG. 17 is a block diagram showing an eleventh embodiment of the present invention.

FIG. 18 is a block diagram showing a twelfth embodiment of the present invention.

FIG. 19 is an explanatory diagram of signal frequencies of various parts in the system according to the twelfth embodiment of the present invention.

FIG. 20 is a block diagram showing a conventional wireless telephone.

FIG. 21 is a block diagram showing another conventional wireless telephone.

[Explanation of symbols]

 1 Voltage Controlled Oscillator 2 Frequency Variable PLL Circuit 3 Oscillator 4 Fixed Frequency Division PLL Circuit 5 Oscillator 6 Fixed Frequency Division PLL Circuit 7 Buffer Amplifier 8 Buffer Amplifier 9 Buffer Amplifier 10 Low-pass Filter 11 Mixer 12 Bandpass Filter 13 High Frequency Switch circuit 14 Amplifier 15 Amplifier 16 High-frequency distributor 17 Low-pass filter 18 Mixer 19 Band-pass filter 20a Oscillator 20b Oscillator 20c Oscillator 21 Temperature-compensated crystal oscillator 22 High-frequency multiplier 23 Voltage-controlled oscillator 24 Buffer amplifier 25 Frequency variable PLL Circuit 26 High-frequency distributor 27a Band-pass filter 27b Band-pass filter 28a High-frequency distributor 28b High-frequency distributor 29 High-frequency synthesizer 30 High-frequency synthesizer 31 Interlocking high-frequency switch circuit 32 High-frequency splitter 41 Transmitter / receiver duplexer 42 Antenna device 43 Transmission / reception Switching device 51a Modulator 51b Modulator 52 Amplifier 53a Bandpass filter 53 b bandpass filter 53c bandpass filter 54 mixer 55 transmission system IF circuit 56 amplifier 61 demodulator 62 bandpass filter 63 mixer 64 bandpass filter 65 mixer 66 amplifier 67a bandpass filter 67b bandpass filter 68 receiving system IF circuit 69 amplifier 100 reference oscillating means 101 transmitting local oscillating means 102 receiving local oscillating means 103 intermediate frequency receiving means

Claims (3)

[Claims] 1. A first band (transmit band center frequency F
t1, the reception band center frequency Fr1, the band width B1) and the second band (the transmission band center frequency Ft2, the reception band center frequency Fr2, the band width B2) in the radio telephone which transmits and receives the radio signals, a plurality of reference oscillation signals By combining the reference oscillation means to be generated and this reference oscillation signal, a signal having a frequency of Ft1- (B1 / 2) to Ft1 + (B1 / 2) for the first band and a first local oscillation signal are transmitted. A local oscillator for transmission that generates signals of frequencies Ft2- (B2 / 2) to Ft2 + (B2 / 2) for the second band; and a modulator that modulates the local oscillator signal for transmission with a baseband signal. An intermediate frequency receiving means for receiving and processing a signal whose reception intermediate frequency fr is | Ft1-Fr1 | or | Ft2-Fr2 | Depending on the combination of the oscillation signals, the reception intermediate frequency fri is | Ft1-Fr1 | as the local oscillation signal for reception.
In the case of, a signal having a frequency of Ft1- (B1 / 2) to Ft1 + (B1 / 2) for the first band and a frequency of Fr2 ± fri- (B2 / 2) for the second band. ) -Fr2 ± fri + (B
2/2) and the reception intermediate frequency fr is | Ft2-F
In the case of r2 |, the frequency is Fr1 ± fri− (B1 / 2) to Fr1 ± fri + (B for the first band.
1/2) signal and a receiving local oscillating means for generating a signal having a frequency of Ft2- (B2 / 2) to Ft2 + (B2 / 2) for the second band. Wireless phone to. 2. The first band (transmission band center frequency F
t1, the reception band center frequency Fr1, the band width B1) and the second band (the transmission band center frequency Ft2, the reception band center frequency Fr2, the band width B2) in the radio telephone which transmits and receives the radio signals, a plurality of reference oscillation signals A reference oscillating unit for generating, a modulating unit for modulating an oscillating signal having a frequency fti lower than the first and second transmission bands with a baseband signal, and a combination of the reference oscillating signal, the first local oscillating signal for transmission, Frequency of Ft1 ± fti− (B1 / 2) to Ft1 ± fti + (B
1/2) signal and the second band, the frequency is Ft2 ± fti− (B2 / 2) to Ft2 ± fti + (B
2/2) transmitting local oscillating means, and a transmitting means for frequency-mixing the output signal from the modulating means and the transmitting local oscillating signal to convert them into radio signals in the first and second transmission bands. A credit frequency conversion means, an intermediate frequency reception means for receiving and processing a signal whose reception intermediate frequency fr is | Ft1-Fr1 | or | Ft2-Fr2 | , The reception intermediate frequency fr is | Ft1-Fr1 |
In the case of, a signal having a frequency of Ft1- (B1 / 2) to Ft1 + (B1 / 2) for the first band and a frequency of Fr2 ± fri- (B2 / 2) for the second band. ) -Fr2 ± fri + (B
2/2) and the reception intermediate frequency fr is | Ft2-F
In the case of r2 |, the frequency is Fr1 ± fri− (B1 / 2) to Fr1 ± fri + (B for the first band.
1/2) signal and a receiving local oscillating means for generating a signal having a frequency of Ft2- (B2 / 2) to Ft2 + (B2 / 2) for the second band. Wireless phone to. 3. The radio telephone according to claim 1, wherein the reference oscillating means has a variable frequency oscillator whose frequency variable width Δ1 is max (B1, B2) ≦ Δ1 ≦ B1 + B2. .