WO1999000910A1

WO1999000910A1 - Communication device

Info

Publication number: WO1999000910A1
Application number: PCT/JP1998/002892
Authority: WO
Inventors: Shinichi Kinouchi; Yuichi Kanayama; Norihiko Mikoshiba
Original assignee: Asahi Kasei Kogyo Kabushiki Kaisha; Asahi Kasei Microsystems Co., Ltd.
Priority date: 1997-06-27
Filing date: 1998-06-26
Publication date: 1999-01-07
Also published as: AU7934898A

Abstract

Inexpensive dual-band-ready FDD/TDMA communication device having a small size and light weight. The communication device is provided with a received signal change-over switch (2), a reception mixer (3), a demodulator (4), a high-frequency variable frequency oscillator (5), IF oscillators (8 and 9), an IF signal change-over switch (7), a transmission system mixer (6), a quadrature modulator (10), and a signal-to-be-transmitted change-over switch (11). The frequencies of the variable frequency oscillator (5) and the IF oscillators (8 and 9) are determined appropriately by setting the intermediate frequency for reception at about half the difference between two receiving bands.

Description

Technical field

The present invention relates to a dual band communication device. More specifically, the present invention provides a pair of a transmission band At (frequency range: fAt1 to fAt2) and a reception band Ar (frequency range: fAr1 to ίAr2). , And a pair of transmission band Bt (frequency range: ίBt1 to fBt2) and reception band KBr (frequency range: fBr1 to ίBr2) The present invention relates to a communication device having a second communication band including: Background art

Conventionally, there have been various systems for radio communication using radio waves, such as analog systems and digital systems, and each system is assigned a frequency band centering on the UHF band. However, the number of subscribers of digital mobile phones and the like has increased remarkably in recent years, and communication traffic has become extremely congested, so that subscribers are unable to freely access the communication network.

One way to circumvent this problem is to provide a way for some of the users of a wireless communication system to communicate when the traffic is very congested. Methods have been proposed to get into the frequency band of other relatively vacant wireless communication systems.

Also, when different wireless communication systems are used in remote areas, there is a demand for telephones that can be used in the frequency band of either wireless communication system. Is growing.

However, two different wireless communication systems usually use different frequency bands and also use different transmission band and reception band frequencies.

Communication devices that could be used in both wireless communication systems had separate and independent communication devices for each of the two wireless communication systems. Since each communication system has a different intermediate frequency, the number of circuits that can be shared is small, the number of oscillators is large, and this communication device was large.

Japanese Patent Application Laid-Open Publication No. H5-244032, which is one of the published patent publications in Japan, describes a local oscillator having a frequency substantially intermediate between the first communication band and the second communication band and each band. The signal processing circuit for the intermediate frequency and later is shared by mixing the signal with the signal of the intermediate frequency. However, in order to narrow the variable frequency range of the local oscillator, two local oscillators were required, one for the transmission band and one for the reception band.

Japanese Patent Application Laid-Open Publication No. Hei 7-254864, which is a published patent application of a patent application filed in Japan based on the German application (P4338721.7), describes how to determine the frequency of a local oscillator. Is the same as that disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 5-244032, but by making the variable frequency range of the local oscillator very wide, the same intermediate frequency is used for both transmission and reception. The configuration uses only one local oscillator.

Regarding the above two published patent publications, the descriptions in both published patent publications are up to the intermediate frequency, and the transmitting unit employs an indirect modulation method.

However, considering the specific configuration of signal processing from the frequency of the communication band to the frequency of the baseband and the frequency control range of the actual oscillator, the circuit configuration is complicated and the number of oscillators cannot be increased. There is a problem that it cannot be obtained. In general, there is a strong demand for smaller, lighter, and lower cost communication devices for portable use, and there is a problem with the above-described large-sized configuration.

Therefore, an object of the present invention is to provide a small-sized, lightweight, low-cost semiconductor device compatible with dual bands, and a communication device using the same, in view of the above points. Disclosure of the invention

The present inventors have proposed that a dual-band communication device such as an FDD communication system or a TDMA communication system has one voltage-controlled variable-frequency high-frequency signal oscillator (high-frequency VCO) and two voltage-controlled intermediate-frequency signals. At least an oscillator (IFVCO), a receiving high-frequency signal switching switch, a receiving mixer, a demodulator, a transmitting mixer, a modulator, and a transmitting high-frequency signal switching switch are arranged. By setting the intermediate frequency for reception to about half the difference between the two reception bands and setting the frequencies of the high-frequency VCO and the two IFVCs to appropriate frequencies, it is compact, lightweight and low-cost. It has been found that such a communication device can be realized, and the present invention has been achieved.

That is, in the first embodiment of the present invention, a pair of transmission band At (frequency range: f Atl to f At 2) and reception band Ar (frequency range: f A r 1 to f A r 2) ), A pair of transmission bands Bt (frequency range: iBtl to iBt2) and a reception band B'r (frequency range: fBr1 to fB). r 2) a communication device having a second communication band including:

An intermediate frequency oscillating means for outputting a signal having a first oscillating frequency and a second oscillating frequency to form the first and second communication bands; and the first and second oscillating means. Modulation for forming the transmission band At and the transmission band KBt by a direct modulation method in response to a signal having a frequency. Means

It is provided with. According to the configuration of the present invention, it is possible to realize a small-sized, light-weight, low-cost communication device that supports dual band.

According to a second aspect of the present invention, in the first aspect, the transmission band At is 880 to 915 MHz, and the reception band A r is the same. 9 25 to 96 MHz, the transmission band Bt force? 1 7 1 0 to 1 78 5 MHz, the reception band Br force?

1805 to 188 MHz. According to such a configuration of the present invention, GSM (A t = 88 0 to 91 15 MHz, A r = 9 25 to 9

(6 MHz) and DC S 1800 (B t = 1710 0-785 MHz, Br = l 805-188 MHz) I can do it.

According to a third embodiment of the present invention, as shown in FIG. 8A, in the first embodiment, a variable frequency oscillator that outputs a signal having an intermediate oscillation frequency between the two reception bands,

A first fixed frequency oscillator that outputs a signal having a frequency that is a difference between the frequency of the transmission band At and the oscillation frequency of the variable frequency oscillator;

A second fixed frequency oscillator that outputs a signal having a frequency that is a difference between the frequency of the transmission van KBt and the oscillation frequency of the variable frequency oscillator;

An oscillator switching switch for switching an output of the first fixed frequency oscillator, and an output of the second fixed frequency oscillator;

A first phase shift circuit that converts a signal output from the variable frequency oscillator into a signal having a phase difference of 0 ° and 90 °,

A second phase shift circuit that converts a signal output from the oscillator switching switch into a signal having a phase difference between 0 ° and 90 °; A phase switch that switches the combination of the output signals of the first phase shift circuit to (0,, 90 °) or (190, 0 °) according to the communication band to be used. Circuit and

A first mixer circuit that inputs a signal output from the phase switch circuit and a signal output from the second phase shift circuit;

A first adder circuit for inputting a signal output from the first mixer circuit. According to such a configuration of the present invention, an external filter for removing unnecessary waves is not required, so that a circuit suitable for integration in the IC can be realized.

According to a fourth aspect of the present invention, in the third aspect, the variable frequency oscillator covers a range of 133 to 144 MHz. According to the configuration of the present invention, since the variable frequency range of the external oscillator can be narrowed, the variable frequency oscillator can be driven at a low voltage, and not only can the size and power consumption be reduced, but also the phase noise can be reduced. High performance can be realized.

According to a fifth aspect of the present invention, in the first aspect, the first oscillating frequency is 460 to 540 MHz and the second oscillating frequency is 360 to 380 MHz. It is like that. According to the configuration of the present invention, the frequency range of the variable frequency oscillator can be narrowed.

According to a sixth embodiment of the present invention, as shown in FIG.

A first switch circuit that switches a reception signal having a reception frequency in the first communication band and a reception signal having a reception frequency in the second communication band as a reception signal of the communication device;

A first reception mixer circuit that inputs a signal output from the first switch circuit and a signal output from the variable frequency oscillator; It is provided with. According to such a configuration of the present invention, it is possible to realize a dual-band communication device in which circuits after the first reception mixer circuit are shared with a small circuit scale.

According to a seventh embodiment of the present invention, as shown in FIG.

A second reception mixer circuit for inputting a reception signal having a reception frequency in the first communication band and a signal output from the variable frequency oscillator; and having a reception frequency in the second communication band. A third reception mixer circuit that inputs a reception signal and a signal output from the variable frequency oscillator; a signal output from the second reception mixer circuit; and a third reception mixer circuit. A second switch circuit for switching the output signal as a reception intermediate frequency signal of the communication device; and

It is provided with. According to the configuration of the present invention, it is possible to realize a dual-band communication device in which the circuits after the second switch circuit are shared with a small circuit scale.

According to an eighth aspect of the present invention, as shown in FIG. 8D, in the sixth or seventh aspect,

A second fixed frequency oscillator having a frequency different from a signal output from the first reception mixer circuit or the signal output from the second switch circuit;

A first IF mixer, or a first IF receiving mixer that inputs a signal output from the second switch circuit and a signal output from the fixed frequency oscillator;

A first phase converter that divides the signal output from the fixed frequency oscillator by 4 and outputs a signal having a phase difference of 0 ° and 90 °;

The first IF converter receives the first IF signal based on a signal output from the first phase converter. A first demodulator for demodulating the signal output from the

It is provided with. In such a configuration of the present invention, since a double super-dyne configuration is adopted, it is possible to give flexibility to the frequency plan. That is, in this circuit configuration, it is possible to achieve a frequency blank such that unnecessary waves at the time of transmission do not enter the reception band, and it is possible to satisfy the standards of GSM and DSC180.

According to a ninth embodiment of the present invention, as shown in FIG. 8E, in the eighth embodiment, the transmission band At is 880 to 915 MHz, and the reception band Ar is 925 Up to 960 MHz, the transmission band B t force 1710 0 to 1785 MHz, the reception band B r force? When the frequency of the signal output from the first reception mixer circuit or the second switch circuit is f 1, The frequency of the fixed frequency oscillator of No. 2 is set to 4 × f 1/5. According to the configuration of the present invention, a dual-mode communication device that realizes both transmission and reception can be configured by using only three oscillators, one variable frequency oscillator and two fixed frequency oscillators.

According to a tenth aspect of the present invention, as shown in FIG. 8F, in the sixth or seventh aspect,

A second fixed frequency oscillator having a frequency different from the signal output from the first reception mixer circuit or the second switch circuit;

A second IF reception mixer that inputs a signal output from the reception mixer and a signal output from the fixed frequency oscillator,

A second phase converter that divides the signal output from the fixed frequency oscillator by 8, and outputs a signal having a phase difference of 0 ° and 90 °;

A second demodulator that demodulates a signal output from the second IF reception mixer with a signal output from the second phase converter. It is provided with. According to the configuration of the present invention, a dual-mode communication device that realizes both transmission and reception can be configured by using only three oscillators, one variable frequency oscillator and two fixed frequency oscillators. .

As shown in FIG. 8G, in the eleventh embodiment of the present invention, in the tenth embodiment, the transmission band At is 880 to 915 MHz, and the reception band A is r is 925 to 960 MHz, the transmitting band Bt force ^S 171 0 to 178 5 MHz, the receiving ^band B r force ^{Ϋ 180} 5 to 1880 ΜΗ ありWhen the frequency of the signal output from the first reception mixer circuit or the second switch circuit is f 2, the frequency of the second fixed frequency oscillator becomes 8 × f 2 7 It is like that. According to such a configuration of the present invention, a dual mode communication device that realizes both transmission and reception can be configured by using only three oscillators, one variable frequency oscillator and two fixed frequency oscillators. .

As shown in FIG. 8H, the twelfth aspect of the present invention is based on the sixth or seventh aspect,

A frequency divider 1 that divides the signal output from the high-frequency oscillator by 2 or 3 and

A first IF signal switching switch for selecting a signal output from the frequency divider 1 in accordance with a reception band;

A first IF mixer, or a third IF mixer for inputting a signal output from the second switch circuit and a signal output from the first IF signal switching switch; ,

A frequency divider 2 that divides the frequency of the signal output from the IF signal switching switch by 3 if the signal is divided by 2 and divides the signal by 2 if the signal is divided by 3;

A demodulation wave switching switch for selecting an output of the frequency divider;

The signal output from the demodulation wave switching switch is frequency-divided by 2, and 0 ° and 9 A divide-by-2 phase converter for converting to a signal having a phase difference of 0 °,

A third demodulator that demodulates a signal output from the third IF reception mixer with a signal output from the divide-by-2 phase converter.

It is provided with. According to the configuration of the present invention, a dual-mode communication device that realizes both transmission and reception can be configured by using only two oscillators, one variable frequency oscillator and one fixed frequency oscillator. .

According to a thirteenth aspect of the present invention, in the above-described first to twelfth aspect, the oscillation frequency of the high-frequency oscillator is set to 180 MHz. According to the configuration of the present invention, a dual-mode communication device that realizes both transmission and reception can be configured by using only two oscillators, one variable frequency oscillator and one fixed frequency oscillator. .

In a fifteenth aspect of the present invention, as shown in FIG. 8I, in any one of the eighth to tenth aspects, the transmission band At is 880 to 915 MHz. The receiving band Ar is 925-960 MHz, the transmitting band Bt force? 1 7 10 to 17 8 5 MHz, the receiving band Br force? 185 MHz to 188 MHz, and the frequency of the signal output from any one of the first IF reception mixer and the third IF reception mixer is two communication bands. The difference between the receiving frequency and the transmitting frequency of the code (I f A rl — f A tl 1 = 1 f A r 2-f A t 2 I f B rl-f B tl 1 = 1 f B r 2-f B t 2 I), between 45 and 95 MHz. According to the configuration of the present invention, it is possible to realize a communication device that is dual-band compatible, small, lightweight, and low in cost.

In the fifteenth embodiment of the present invention, as shown in FIG. 8J, a pair of transmission bands At (frequency range: f Atl to f At 2) and a reception band A r (frequency range: f A r1 to f A r 2) and a pair of transmission bands B t (Frequency range: fBt1 to fBt2) and a communication device having a second communication band including a reception band KBr (frequency range: fBr1 to fBr2) When,

A frequency divider that divides the signal output from the high-frequency oscillator by 2 or 3;

An IF signal switching switch for selecting a signal output from the frequency divider according to a transmission band;

A transmission-type mixer that inputs a signal output from the IF signal switching switch and a signal output from a high-frequency variable frequency oscillator;

According to a sixteenth aspect of the present invention, in the fifteenth aspect, the transmission band At is 880 to 915 MHz, the reception band Ar is 925 to 960 MHz, The transmission band Bt is 1710 to 1785 MHz, the reception band Br force is 1805 to 1880 MHz, and the high frequency oscillator is 180 MHz. A signal having a frequency is output. According to the configuration of the present invention, a dual-mode communication device that realizes both transmission and reception is realized by using only two oscillators, one variable frequency oscillator and one fixed frequency oscillator. it can.

According to a seventeenth mode of the present invention, in the above-mentioned fifteenth mode, the transmission band At is 880 to 915 MHz and the reception band Ar is 925 to 960 MHz. The transmission band Bt is 1710 to 1785 MHz, the reception band Br is 1805 to 188 MHz, and the high-frequency variable frequency oscillator is Cover the range of 133 to 1455 MHz. According to the configuration of the present invention, a dual-mode communication device that realizes both transmission and reception by using only two oscillators, one variable frequency oscillator and one fixed frequency oscillator, is provided. Can be configured.

According to a eighteenth aspect of the present invention, in any one of the first to seventeenth aspects, communication is performed by an FDD (frequency division duplex) or TDMA (time division multiple access) communication method. is there. According to the configuration of the present invention, it is possible to realize a small-sized, lightweight, and low-cost communication device that supports dual band. In addition, a low-power-consumption communication device can be realized by using a low-voltage-drive oscillator that is easily available.

According to a nineteenth aspect of the present invention, in any one of the first to seventeenth aspects, the communication device is used as a transceiver device. With the configuration of the present invention, it is possible to realize a small-sized, light-weight, and low-cost communication device that supports dual band. In addition, a low-power-consumption communication device can be realized by using an easily available oscillator driven at low voltage.

The semiconductor device according to the twenty-fifth aspect of the present invention includes a pair of a transmission band At (frequency range: f At1 to f At 2) and a reception band Ar (frequency range: f A r1). ~ F A r 2), a pair of transmission bands B t (frequency range: f B t 1 to f B t 2) and a reception band KB r (frequency range: f B r 1) ~ FBr2), an intermediate frequency input terminal for inputting a signal having a first oscillation frequency and a second oscillation frequency to form a second communication band including

An intermediate frequency signal switching switch for selecting and outputting any one of the two signals input from the intermediate frequency input terminal;

A signal output from the intermediate frequency signal switching switch; A transmission mixer that receives a signal output from the frequency oscillator as an input, a quadrature modulator that receives a signal output from the transmission mixer and a baseband signal,

A transmission signal switching switch for distributing and outputting a signal output from the quadrature modulator in accordance with a transmission band;

A reception signal switch for selecting one of the reception bands Ar and Br;

A reception mixer to which a signal output from the reception signal switching switch and a signal output from the high frequency variable frequency oscillator are input;

Phase shift means for shifting the phase of the signal output from the intermediate frequency signal switching switch;

A demodulator for demodulating a reception intermediate frequency signal output from the reception mixer with a signal output from the phase shift means;

It is provided with. With the configuration of the present invention, a low-power semiconductor device compatible with dual band can be realized. As a result, a small, lightweight, and low-cost communication device can be provided.

According to a twenty-first aspect of the present invention, in the twenty- ^fifth aspect, the transmitting band At force ⁵ , 880 to 915 MHz, and the receiving band Ar are 925 to 960. MH z, in which the transmission bands B t is configured to be 1 7 1 0~ 1 7 8 5MH z, the receiving van KB r force ^{s 1 8 0 5~ 1 8 8} 0 MH z.

According to a twenty-second aspect of the present invention, in the twentieth aspect, the transmission-system mixer is

A first phase shift circuit that converts a signal output from the high frequency variable frequency oscillator into a signal having a phase difference of 0 ° and 90 °,

The signals output from the intermediate frequency signal switching switch are 0 ° and 90 °. A second phase shift circuit that converts the signal into a signal having a phase difference of

A phase switch circuit that switches a combination of output signals of the first phase shift circuit to (0 °, 90 °) or (90, 0 °) according to a communication band to be used. When,

A first adder circuit for inputting a signal output from the first mixer circuit.

According to a twenty-third aspect of the present invention, in the twenty-third aspect, the frequency of the signal output from the high-frequency variable frequency oscillator is in a range of 133 to 145 MHz. It is.

According to a twenty-fourth aspect of the present invention, in the twenty-fifth aspect, the first oscillation frequency is set to 460 to 540 MHz, and the second oscillation frequency is set to 360 to 380 MHz. It is that.

According to a twenty-fifth aspect of the present invention, there is provided a reception signal switching switch according to the twenty-fifth aspect, and a reception mixer A for receiving a signal of a reception band Ar instead of the reception mixer. A reception mixer B for receiving the signal of the reception van KBr, and a second reception signal switching switch for selectively outputting the output signals from the reception mixers A and B are used.

According to a twenty-sixth aspect of the present invention, in addition to the twenty-seventh or twenty-fifth aspect, an IF reception mixer is provided at a stage preceding the demodulator, and an output from the intermediate frequency signal switching switch Is input to the IF reception mixer.

The semiconductor device according to the twenty-seventh aspect of the present invention includes a pair of a transmission band At (frequency range: fAtl to fAt2) and a reception band Ar (frequency range: fAr1 to fAt1). r A r 2) and a pair of transmission vans KB t (Frequency range: fBt1 to fBt2) and reception band KBr (frequency range: fBr1 to fBr2) An input terminal for inputting a signal having a frequency,

A frequency divider 1 for dividing the signal from the input terminal by two or three, and an IF signal switching switch for selecting a signal output from the frequency divider 1 in accordance with a transmission band;

A transmission mixer that receives a signal output from the IF signal switching switch and a signal output from a high-frequency variable frequency oscillator,

A quadrature modulator that receives a signal output from the transmission mixer and a baseband signal,

A transmission signal switching switch for distributing and outputting the signal output from the quadrature modulator in accordance with a transmission band;

A reception signal switching switch for selecting one of the reception bands A r and Br;

The IF signal switching switch for selecting a signal output from the frequency divider 1 in accordance with a reception band;

A signal output from the IF signal switching switch; and an IF reception mixer for receiving a reception intermediate frequency signal output from the reception mixer.

A frequency divider 2 that divides the signal output from the IF signal switching switch by 3 if the signal is divided by 2 and divides the signal by 2 if the signal is divided by 3;

A demodulation wave switching switch for selecting the output of the frequency divider 2; and a signal output from the demodulation wave switching switch, divided by 2 and converted into a signal having a phase difference between 0 ° and 90 °. A divide-by-2 phase converter, A demodulator for demodulating a signal output from the IF reception mixer with a signal output from the divide-by-2 phase converter.

It is provided with.

According to a twenty-eighth aspect of the present invention, in the twenty-seventh aspect, the fixed oscillation frequency is set to 180 MHz.

According to a twentieth aspect of the present invention, in the twenty-seventh aspect, the transmission band At is 880 to 915 MHz, the reception band Ar is 925 to 960 MHz, the transmission bands B t force ^{s 1 7 1 0~ 1 7 8} 5MH z, the receiving van KB r: is obtained by configured to be ¾ l 8 0 5~ 1 8 8 0MH z?.

According to a thirty-fifth aspect of the present invention, in the twenty-seventh aspect, the frequency of the signal output from the high-frequency variable frequency oscillator covers a range of 133 to 145 MHz. It is composed.

According to a thirty-first embodiment of the present invention, in addition to the above-mentioned twenty-first embodiment, a variable gain amplifier is provided in a preceding stage of the demodulator.

According to a thirty-second embodiment of the present invention, in addition to the features of the twenty-seventh embodiment, a variable gain amplifier is provided in a stage preceding the demodulator.

The 33rd embodiment of the present invention is the same as the 20th embodiment, except that a driver corresponding to each transmission band is provided after the transmission signal switching switch.

According to a thirty-fourth aspect of the present invention, in addition to the features of the twenty-seventh aspect, a driver corresponding to each transmission band is provided after the transmission signal switching switch. BRIEF DESCRIPTION OF THE FIGURES

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 diagram showing a detailed circuit configuration of the image reduction mixer and the single-sided band mixer.

FIG. 4 is a block diagram showing a third embodiment and 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.

FIG. 7 is a block diagram showing a seventh embodiment of the present invention.

FIG. 8A to FIG. 8J are auxiliary drawings described so that each configuration of the present invention can be easily understood. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, each embodiment of the present invention will be described in detail.

(Embodiment 1)

FIG. 1 is a circuit diagram showing a first embodiment of the present invention. In the figure, 1 is a low-noise amplifier for the first communication band, 13 is a low-noise amplifier for the second communication band, 2 is a reception signal switching switch, 3 is a reception mixer circuit, and 4 is a demodulator Reference numeral 5 is a high-frequency variable frequency oscillator, 6 is a transmission system mixer, 7 is an IF signal switching switch, 8 is an IF oscillator A, 9 is an IF oscillator B, 10 is a quadrature modulator, and 11 is a transmission signal switching switch. 12, a driver amplifier for the first communication band, 14 a driver amplifier for the second communication band, 16 a reception processing circuit, and 17 a transmission signal processing circuit.

The high-frequency variable frequency oscillator 5, IF oscillator A (8) and IF oscillator B (9) shown in Fig. 1 may use a VC0 module, or may be configured with transistors, varicaps, tank circuits, etc. Is also good. Also determine the frequency Therefore, it can be used in combination with a PLL circuit.

The receiving mixer 3 may be a Gilbert cell mixer or an image rejection mixer. Also, it is possible to configure in combination with a filter for removing unnecessary waves.

The demodulator 4 converts the signal output from the IF signal switch 7 into a signal having a phase difference of 0 ° and 90 °, and converts this signal and the reception intermediate frequency signal output from the reception mixer 3. This is to obtain a demodulated signal by mixing. Here, the phase difference signal only needs to have a phase difference of 0 ° and 90 °, and may be a combination of a capacitor and a resistor, or a combination of a flip-flop circuit and a plurality of signals. A phase shift circuit may be combined.

The demodulator 4 may be configured to have one receive intermediate frequency and directly obtain a demodulated signal, or to have two or more receive intermediate frequencies and obtain a demodulated signal after passing through several stages of mixer circuits. But it is good. In addition, a variable gain amplifier can be provided to keep the demodulated output signal within a certain range. This gain control is usually provided by a microcomputer or the like that manages the communication system of the communication device. However, this is not particularly limited.

The IF signal switching switch 7 and the IF oscillator A (8), which are fixed-frequency oscillators, depend on which of the two communication bands to use, and in which operation mode, such as transmission, reception, or standby. It outputs either frequency signal of IF oscillator B (9). This switching control is normally supplied from a microcomputer or the like that manages the communication system of the communication device. This is not particularly limited.

The transmission mixer 6 mixes the output signal from the high-frequency variable frequency oscillator 5 with the output signal of the IF signal switching switch 7 to obtain a transmission carrier. It is. The transmission system mixer 6 may be a double sideband mixer or a single sideband mixer combined with a phase shift circuit. Whether to take the low sideband The high sideband is determined by whether the transmission band is At or Bt. It can also be configured in combination with a filter to remove unwanted waves.

(Embodiment 2)

Next, a second embodiment of the present invention will be described.

The frequency range of one transmitting band At and the receiving band Ar is 880 to 915 MHz and 925 to 960 MHz, and the other transmitting band Bt and the receiving band KBr are frequency ranges. The dual-band transceivers with the frequencies of 170 to 180 MHz and 180 to 180 MHz are configured as shown in Fig. 2.

In the actual transceiver device, an antenna, a communication band switching switch, a transmission / reception switching switch, a power amplifier, etc. are required as the transmission / reception processing circuits 16 and 17 shown in FIG. Become.

The configuration of the communication device, the setting of the intermediate frequency, and the frequency setting of the high frequency variable frequency oscillator, which are the features of the second embodiment, will be described below.

Since the frequency difference between the two receiving bands is from 880 MHz (= | fBr1-fAr1I) to 92 MHz (= IfBr2-fAr2I). It is preferable to select a frequency between 450 MHz and 450 MHz as the receiving IF frequency. Further, it is preferable to select a frequency between 365 MHz and 370 MHz as the frequency of the offset oscillator for the transmission van Bt.

The following describes a case where the IF frequency for reception is 460 MHz and the frequency of the offset oscillator for the transmission band KBt is 365 MHz. At this time, the frequency of the high-frequency variable frequency oscillator is set to 1340 to 1420 MHz.

The receiving mixer 3 has an image rejection mixer 101 (see Fig. 3). And a single super-heterodyne system as the receiving system. As the transmission mixer 6, a single-sideband mixer 102 (see Fig. 3) is used.

FIG. 3 shows a detailed configuration example of the dual-band image rejection mixer 101 and the single-side band mixer 102.

The signal of the high-frequency variable frequency oscillator 5 is converted into a phase difference of 0 ° and 90 ° by the phase shifter 25a, and the output combination is changed by the reception band Ar or Br. A signal of (0 °, 190 °) or (190 °, 0 °) is output from the phase shift switch 25b. The signal output from this switch 25b and the received signal are mixed by mixers 21 and 22, converted into 0 ° and 90 ° phases by phase shifter 23, and then added. By adding the two signals with the unit 24, it is possible to obtain an IF received signal of the same frequency with suppressed images in either band. That is, in the case of the receiving band Ar, the image signal of 184 MHz to 188 MHz is suppressed, and in the case of the receiving band Br, the image signal of 885 MHz to 960 MHz is suppressed. You. Here, the phase shifter 23 may be between the mixers 21 and 22 and the reception signal input terminal.

On the other hand, at the time of transmission, as in the case of reception, the combination of the phase shift of the signal output from the high-frequency variable frequency oscillator 5 is switched according to the transmission band At or Bt, and the IF oscillator A (8 ) Or IF oscillator B (9) is switched by IF signal switching switch 7. After the signal output from the IF signal switching switch 7 is converted into a phase of 0 ° and 90 ° by the phase shifter 29 and mixed with the mixers 26 and 27, the adder 3 By adding the two signals at 0, it is possible to obtain a transmission carrier with a single-sideband image suppressed in either band. That is, In the case of the transmission band At, it becomes a low sideband single-side band mixer, and a signal of 880 to 915 MHz is output.In the case of the transmission band Bt, it becomes a high sideband single-side band mixer. , 1710 to 1785 MHz signals are output.

With this configuration, the phase shifter 25a and the phase shift switching switch 25b are common to the receiving system and the transmitting system, and the circuit scale can be reduced. Further, the image suppression filter before the reception mixer 3 is not required.

In the dual-band transceiver configured as shown in Fig. 2, the operation when the transmission band and the reception band are At, Ar, Bt, and Br are as follows. Become.

During reception in the reception band Ar, the signal output from the low-noise amplifier 1 for the reception band Ar (925 to 960 MHz) is received by the reception mixer 3 (image rejection mixer). The signal of IF frequency (460 MHz) is obtained by mixing the signal of high frequency variable frequency oscillator 5 (1385 to 144 MHz) at 101). The IF frequency signal is adjusted to an appropriate level through a band-limiting filter 51 and a variable gain amplifier 52, and then converted to 0 ° and 90 ° phases by a phase shifter 54. A baseband signal output is obtained by mixing the signal (460 MHz) having the frequency of A (8) with the demodulator 53. The frequency of the IF oscillator A may be 920 MHz. In this case, it is sufficient to divide the frequency by 2 to obtain phase signals of 0 ° and 90 °.

At the time of transmission in the transmission band At, the frequency of the high-frequency variable frequency oscillator 5 is 45 MHz lower than that at the time of reception (134 0 to 1375 MHz), and this high-frequency variable oscillator 5 is used. Mix the frequency oscillator signal and the signal with the frequency of the IF oscillator A used during reception (460 MHz) with the transmission mixer 6 (single-side band mixer 102) to select the lower sideband. Transport for transmission Get the wave (frequency 880 ~ 910 MHz). The baseband signal is quadrature-modulated with this carrier wave, and output from the transmission band At driver amplifier 12 to obtain a transmission signal.

On the other hand, during reception in the reception band Br, the signal output from the low-noise amplifier 13 for the reception band Br (1805 to 188 MHz) is received by the reception mixer. 3 (Image rejection mixer 101) mixes with the signal of high-frequency variable frequency oscillator 5 (1345 to 1420MHz) to obtain the same IF as reception band Ar. It becomes a signal of the frequency (46 OMHz). The subsequent signal processing method is exactly the same as that for reception in reception band Ar.

At the time of transmission at the time of the transmission van KBt, the signal of the high-frequency variable frequency oscillator 5 uses the same frequency (1345 to 1420 MHz) as the signal at the time of reception. The signal (365 MHz) having the frequency of the IF oscillator B (9) for transmission mode B (9) is mixed by the transmission system mixer 6 (single sideband mixer 102), and the high sideband is selected. As a result, a carrier wave for transmission (frequency 1710 to 1785 MHz) was obtained. The baseband signal is orthogonally modulated with this carrier wave, and output from the driver amplifier 14 for the transmission band KBt to obtain the transmission signal.

According to the second embodiment, the processing of the high frequency signal required for dual band transmission and reception can be configured with a minimum block, and in addition to the two reception bands A r and B r However, since the reception intermediate frequency is the same, the configuration of the reception system after the reception mixer 3 can be simplified. Furthermore, a dual-band communication device can be realized with three oscillators.

(Embodiment 3)

Next, a third embodiment of the present invention will be described.

The frequency range of one transmission band At and the reception band Ar is 880 to 915 At MHz and 925 to 960 MHz, the frequency range of the other transmitting band KBt and receiving band Br is 1710 to 1785 MHz and 1805 to 188 MHz. The dual-band transceiver is configured as shown in Fig. 4.

The configuration of the communication device, the setting of the intermediate frequency, and the setting of the frequency of the high frequency variable frequency oscillator 5, which are features of the third embodiment, will be described below.

Since the frequency difference between the two receiving bands is from 880 MHz (= 1 fBr1-fAr1I) to 92 MHz (= | fBr2-fAr2I). It is preferable to select a frequency between 450 MHz and 450 MHz as the receiving IF frequency. It is also preferable to select a frequency close to the difference between the frequency of the reception band and the frequency of the transmission band as the frequency of the second reception IF signal.

Hereinafter, the IF frequency for reception is 45 OMHz, the IF frequency for second reception is 90 MHz, the frequency of IF oscillator A (8) used for transmission band At is 495 MHz, and the reception band Ar The case where the frequency of the IF oscillator B (9) used for the transmission band Bt and the reception band Br is 360 MHz is described. At this time, the frequency of the high-frequency variable frequency oscillator 5 is set at 135 to 144 MHz.

As the reception mixer 3, an image rejection mixer 101 (see FIG. 3) is used. As the receiving system, a double superheterodyne system is used, and the second receiving intermediate frequency is 90 MHz. As the transmission mixer 6, a single-side band mixer 102 (see FIG. 3) is used. The circuit configurations of the dual-band image rejection mixer 101 and the single-side band mixer 102 are the same as in FIG. In the dual-band transceiver configured as shown in Fig. 4, the operation when the transmission band and the reception band are At, Ar, Bt, and Br are as follows.

At the time of reception in the reception band Ar, the signal output from the low-noise amplifier 1 for the reception band Ar (925 to 960 MHz) is received by the reception mixer 3 (image-reduction mixer 10). By mixing with the signal of the high-frequency variable frequency oscillator 5 (1375 to 1410 MHz) in 1), a signal of the IF frequency (450 MHz) is obtained. After removing unnecessary waves with the band-limiting filter 51, the received IF signal is mixed with the IF oscillator B (9) (360MHz) signal output from the IF signal switching switch 7 and the IF reception mixer 33. Been 9

It becomes the second reception IF signal of 0 MHz. Further, the second received IF signal is set to an appropriate level through the variable gain amplifier 52, and then the signal of the IF oscillator B (9) output from the IF signal switch 7 is divided by 4 to 0 °. And 90. The demodulator 53 mixes the signal with the phase with the baseband signal to demodulate it into a baseband signal.

At the time of transmission in the transmission band At, the signal of the high-frequency variable frequency oscillator 5 uses the same frequency (1375-140 MHz) at the time of reception. This high frequency variable frequency oscillator signal was output from the IF signal switching switch 7.

1 F The signal of the oscillator A (8) (495 MHz) is mixed with the transmission mixer 6 (single-side band mixer 102), and by selecting the lower sideband, the carrier for transmission (frequency 8 80 to 915 MHz). The baseband signal is quadrature-modulated with this carrier wave, and output from the transmission band At driver amplifier 12 to obtain a transmission signal.

On the other hand, at the time of reception in the reception band Br, the signal output from the low-noise amplifier 13 for the reception band Br (185 to 188 MHz) is received by the reception mixer. The IF frequency (450 MHz) is mixed with the signal of the high frequency variable frequency oscillator 5 (135 MHz to 144 MHz) by the image signal mixer 3 (image rejection mixer 101). ) Signal. The subsequent signal processing method is exactly the same as that for reception in reception band Ar.

At the time of transmission at the time of the transmission van Bt, the signal of the high frequency variable frequency oscillator 5 uses a frequency 5 MHz lower than that at the time of reception (1350 to 1425 MHz). This high-frequency variable frequency oscillator signal is output from the IF oscillator B (9) (36 OMHz) signal output from the IF signal switch 7 and the transmission system mixer 6 (single sideband mixer 102). By mixing and selecting the high sideband, it is possible to obtain a carrier for transmission (frequency 1710 to 1785 MHz). The baseband signal is quadrature-modulated with this carrier, and output from the transmission band Bt driver amplifier 14 to obtain a transmission signal.

In general, in the configuration of FIG. 4, if the frequency of the second received IF signal is f, it is preferable that the frequency of the IF oscillator B (9) is 4 f and the frequency of the first received IF signal is 5 f .

According to the third embodiment, the processing of the high-frequency signal required for the transmission and reception of the dual band can be configured with the minimum block, and in addition to the two reception bands Ar and Br, However, since the reception intermediate frequency is the same, the configuration of the reception system after the reception mixer 3 can be simplified. Also, a dual-band communication device can be realized with three oscillators. Further, according to the third embodiment, it is possible to suppress the appearance of unnecessary waves on the reception band regardless of which band is being transmitted.

(Embodiment 4)

Next, a fourth embodiment of the present invention will be described.

The frequency range of one transmission band At and the reception band Ar is 880 to 915 MHz and 925 to 960 MHz, the other transmit band Bt and receive band Br have frequency ranges of 1710 to 1785 MHz and 1805 to 188 MHz. This dual-band transceiver is configured as shown in FIG. 4 (the block circuit diagram is the same as that of the third embodiment).

The configuration of the communication apparatus, setting of the intermediate frequency, and setting of the frequency of the high frequency variable frequency oscillator 5, which are characteristics of the fourth embodiment, will be described below.

In the fourth embodiment, the frequency of the second reception IF signal is selected to be 95 MHz, which is equal to the frequency difference between reception band Br and transmission band Bt.

Hereinafter, the first reception IF frequency is 475 MHz, the frequency of the IF oscillator A (8) used for the transmission band At is 520 MHz, the reception band Ar, the transmission band B t The case where the frequency of the IF oscillator B (9) used for the reception band Br is 38 OMHz will be described. At this time, the frequency of the high-frequency variable frequency oscillator 5 is set to 133 to 1435 MHz.

As the receiving mixer 3, an image rejection mixer 101 (see FIG. 3) is used. As a receiving system, a double superheterodyne system is used, and the second receiving intermediate frequency is 95 MHz. As the transmission mixer 6, a single-side band mixer 102 (see FIG. 3) is used. The configurations of the dual-band image rejection mixer 101 and the single-side band mixer 102 are the same as in FIG.

In the dual-band transceiver configured as shown in FIG. 4, the operation when the transmission band and the reception band are At, Ar, and Bt and Br is as follows. At the time of reception in the reception band Ar, the signal output from the low-noise amplifier 1 for the reception band Ar (925 to 960 MHz) is received by the reception mixer 3 (image-reduction mixer 1). The signal of the IF frequency (475 MHz) is obtained by mixing the signal of the high-frequency variable frequency oscillator 5 (140 MHz to 144 MHz) at 01). After removing unnecessary waves with the band-limiting filter 51, the received IF signal, the IF oscillator B (9) (380MHz) signal output from the IF signal switch 7 and the IF receive mixer The signal is mixed at 33 to form a second received IF signal of 95 MHz. Further, the second received IF signal is adjusted to an appropriate level through the variable gain amplifier 52, and then the IF oscillator B (9) signal output from the IF signal switching switch is divided by 4 into 0 ° and 90 °. The signal having a phase of ° is mixed with the demodulator 53 to be demodulated into a first-band signal.

At the time of transmission in the transmission band At, the signal of the high-frequency variable frequency oscillator 5 uses the same frequency (140 to 144 MHz) as that at the time of reception. This high frequency variable frequency oscillator signal is fed to the IF oscillator A (8) (520 MHz) signal output from the IF signal switching switch 7 and the transmission system mixer 6 (single sideband mixer 102). By mixing and selecting the lower sideband, a carrier for transmission (frequency 880 to 915 MHz) can be obtained. The baseband signal is quadrature-modulated with this carrier wave, and output from the transmission band At driver amplifier 12 to obtain a transmission signal.

On the other hand, during reception in the reception band Br, the signal output from the low-noise amplifier 13 for the reception band Br (1805 to 188 MHz) is received by the reception mixer. 3 (image rejection mixer 101) mixes with the signal of high-frequency variable frequency oscillator 5 (133 to 140 MHz) to produce IF frequency (475 MHz). Signal. Subsequent signal processing methods are reception band It is exactly the same as the reception at the time of Ar.

At the time of transmission in the transmission band Bt, the signal of the high-frequency variable frequency oscillator 5 uses the same frequency (1330 to 1405 MHz) as at the time of reception. This high-frequency variable frequency oscillator signal is output from the IF oscillator B (9) (380 MHz) output from the IF signal switching switch 7 and the transmission mixer 6 (single sideband mixer 102). By mixing and selecting the high sideband, a carrier wave for transmission (frequency 1710 to 1785 MHz) can be obtained. The baseband signal is quadrature-modulated with this carrier, and the transmission signal is obtained by outputting from the transmission band Bt driver amplifier 14.

According to the fourth embodiment, the processing of high-frequency signals necessary for dual-band transmission and reception can be configured with a minimum number of blocks, and in addition to the two reception bands Ar and Br, Since the receiving intermediate frequency is the same, the configuration of the receiving system after receiving mixer 3 can be simplified. Also, a dual-band communication device can be realized with three oscillators. Furthermore, according to the configuration of the fourth embodiment, it is possible to suppress the appearance of unnecessary waves on the reception band regardless of which band is being transmitted.

(Embodiment 5)

Next, a fifth embodiment of the present invention will be described.

The frequency range of one transmitting band At and the receiving band Ar is 880 to 915 MHz and 925 to 960 MHz, and the other transmitting band KBt and the receiving band KBr The transceivers for dual-band transceivers with the frequencies of 1710 to 1785 MHz and 1805 to 188 MHz are configured as shown in Fig. 5.

Note that the actual transceiver device requires an antenna, a communication band switching switch, a transmission / reception switching switch, a power amplifier, etc. as the transmission / reception processing circuits 16 and 17 shown in Fig. 5. Become. The configuration of the communication device, setting of the intermediate frequency, and setting of the frequency of the high frequency variable frequency oscillator 5 which are features of the fifth embodiment will be described below.

Since the frequency difference between the two reception bands is from 880 MHz (= 1 fBr 1-fAr1I) to 92 MHz (= IfBr2-fAr2I). It is preferable to select a frequency between 450 MHz and 450 MHz as the receiving IF frequency. It is also preferable to select a frequency close to the difference between the frequency of the reception band and the frequency of the transmission band as the frequency of the second reception IF signal.

The following describes a case where the IF frequency for reception is 450 MHz, the IF frequency for second reception is 65 MHz, and the frequency of the offset oscillator for the transmission band Bt is 36 OMHz. At this time, the frequency of the high-frequency variable frequency oscillator is set to 1350 to 144 MHz.

The reception mixer 3 uses an image rejection mixer 101 (see FIG. 3). As the receiving system, a double super-heterodyne system is used, and the second receiving intermediate frequency is set to 95 MHz. As the transmission mixer 6, a single-sideband mixer 102 (see FIG. 3) is used. The configurations of the dual-band image rejection mixer 101 and the single-side band mixer 102 are the same as in FIG.

In the dual-band transceiver configured as shown in Fig. 5, the operation when the transmission band and the reception band are At, Ar, Bt, and Br are as follows.

At the time of reception in the reception band Ar, the signal output from the low-noise amplifier 1 for the reception band Ar (925 to 960 MHz) is received by the reception mixer 3 (image rejection mixer 1). The signal of the IF frequency (455 MHz) is obtained by mixing the signal of the high-frequency variable frequency oscillator 5 (13 180 to 1415 MHz) at 01). This received IF signal is unnecessary for the band-limiting filter 51 After removing the wave, the signal of the IF oscillator A (8) (520 MHz) output from the IF signal switching switch 7 is mixed with the IF receiving mixer 33 to obtain the second receiving IF signal of 65 MHz. Become. Further, the second received IF signal is set to an appropriate level through the variable gain amplifier 52, and then the signal of the IF oscillator A (8) output from the IF signal switching switch 7 is divided by 8 into 0 ° and 9 °. The signal having a phase of 0 ° is mixed with the demodulator 53 to be demodulated into a baseband signal.

At the time of transmission in the transmission band At, the signal of the high-frequency variable frequency oscillator 5 uses a frequency 20 MHz higher than that at the time of reception (1400 to 14435 MHz). This high-frequency variable frequency oscillator signal is output from the IF oscillator A (8) (520 MHz) signal output from the IF signal switch 7 and the transmission system mixer 6 (single-side band mixer 102). By mixing and selecting the lower sideband, a carrier for transmission (frequency 880 to 915 MHz) can be obtained. The baseband signal is quadrature-modulated with this carrier wave, and output from the transmission band At driver amplifier 12 to obtain a transmission signal.

On the other hand, during reception in the reception band Br, the signal output from the low-noise amplifier 13 for the reception band Br (185 to 188 MHz) is received by the reception mixer 3 By mixing with the signal of the high-frequency variable frequency oscillator 5 (135 to 150 MHz) by the (image rejection mixer 101), the same IF frequency (R) as the reception band Ar is obtained. 4 5 5 MHz). The subsequent signal processing method is exactly the same as that for reception in reception band Ar.

At the time of transmission in the transmission band Bt, the signal of the high-frequency variable frequency oscillator 5 uses the same frequency (135 to 1425 MHz) as at the time of reception. This high-frequency variable frequency oscillator signal is supplied to the IF oscillator B (9) (360 MHz) signal output from the IF signal switching switch 7 and the transmission mixer 6 (single By mixing with a sideband mixer 102) and selecting the high sideband, a carrier wave for transmission (frequency 1710 to 1785MHz) can be obtained. The baseband signal is quadrature-modulated with this carrier wave, and output from the transmission band Bt driver amplifier 14 to obtain a transmission signal.

In general, in the configuration of FIG. 5, if the frequency of the second reception IF signal is ί, it is preferable that the frequency of the IF oscillator Β (9) is 8 f and the frequency of the first reception IF signal is 7 f. .

According to the fifth embodiment, the processing of the high-frequency signal required for dual band transmission and reception can be configured with a minimum number of blocks, and in addition to the two reception bands A r and B r However, since the reception intermediate frequency is the same, the configuration of the reception system after the reception mixer 3 can be simplified. Also, a dual-band communication device can be realized with three oscillators. Further, according to the configuration of the fifth embodiment, the appearance of unnecessary waves in the reception band can be suppressed regardless of which band is transmitted.

(Embodiment 6)

Next, a sixth embodiment of the present invention will be described.

The frequency range of one transmission band At and the reception band Ar is 880 to 915 MHz and 925 to 960 MHz, and the frequency range of the other transmission band KBt and the reception band Br is The dual-band transceivers of 170-178 MHz and 1805-1880 MHz are configured as shown in Fig.6.

In an actual transceiver device, an antenna, a communication band switching switch, a transmission / reception switching switch, a power amplifier, and the like are required as the transmission / reception processing circuits 16 and 17 shown in FIG.

The configuration of the communication device, the setting of the intermediate frequency, and the setting of the frequency of the high frequency variable frequency oscillator 5 which are features of the sixth embodiment will be described below. Since the frequency difference between the two receiving bands is from 880 MHz (= I f Br 1-f A r 1 I) to 92 MHz (= | f B r 2-f A r 2 I) It is preferable to select a frequency between 440 MHz and 460 MHz as the reception IF frequency.

Hereinafter, the IF frequency for reception is 450 MHz, the IF frequency for second reception is 90 MHz, and the frequency of the high-frequency variable frequency oscillator 5 is 13500 to 1455 MHz, Set the frequency of the oscillator 36 to 1080 MHz.

As the reception mixer 3, an image rejection mixer 101 (see FIG. 3) is used. As the receiving system, a double superheterodyne system is used, and the second receiving intermediate frequency is 9 MHZ. As the transmission mixer 6, a single-side band mixer 102 (see FIG. 3) is used. The configurations of the dual-band image rejection mixer 101 and the single-side band mixer 102 are the same as in FIG.

In the dual-band transceiver configured as shown in FIG. 6, when the transmission band and the reception band are At, Ar, and Bt, Br, the operation is as follows.

During reception in the reception band Ar, the signal output from the low-noise amplifier 1 for the reception band Ar (925 to 960 MHz) is received by the reception mixer 3 (image rejection). The signal of the IF frequency (450 MHz) is obtained by mixing the signal of the high-frequency variable frequency oscillator 5 (1375 to 140 MHz) with the mixer 101). The received IF signal was filtered by the band-limiting filter 51 to remove unnecessary waves, then the signal of the high-frequency oscillator 36 was frequency-divided by the frequency divider 1 (3 7), and output from the IF signal switching switch 38. The signal (frequency 54 OMHz) is mixed with the IF reception mixer 33 to form a second reception IF signal of 9 OMHz. Further, after the second received IF signal is set to an appropriate level through the variable gain amplifier 52, the signal output from the IF signal switching switch 38 is separated. After being frequency-divided by the frequency divider 2 (3 9) and output from the demodulated wave switching switch 40, the output of the frequency-divided phase converter 41 is restored to a signal having a phase of 0 ° and 90 °. The signal is mixed by the modulator 53 and demodulated into a baseband signal.

At the time of transmission in the transmission band At, the frequency of the high-frequency variable frequency oscillator 5 uses a frequency 45 MHz higher than that at the time of reception (140 to 144 MHz). This high-frequency variable frequency oscillator signal is obtained by dividing the signal of the high-frequency oscillator 36 into two by the frequency divider 1 (37), and outputting the signal (frequency 54 OMHz) from the IF signal switch 38. By mixing with the transmission system mixer 6 (single-side band mixer 102) and selecting the low sideband, a carrier for transmission (frequency 880 to 915 MHz) can be obtained. The baseband signal is quadrature-modulated with this carrier, and is output from the driver amplifier 12 for the transmission band At to obtain a transmission signal.

On the other hand, during reception in the reception band Br, the signal output from the low-noise amplifier 13 for the reception band Br (1805 to 188 MHz) is received by the reception mixer. 3 By mixing with the signal of the high-frequency variable frequency oscillator 5 (1355-1450 MHz) by the (image rejection mixer 101), the IF frequency similar to that of the reception band Ar (45 OMHz). As in the case of reception in the reception band Ar, this reception IF signal is subjected to band-elimination filter 51 to remove unnecessary waves, and then the signal of the high-frequency oscillator 36 is divided by the frequency divider 1 (3 7). The signal is frequency-divided by 3, and the signal (frequency 360 MHz) output from the IF signal switching switch 38 is mixed with the IF reception mixer 33 to become a second reception IF signal of 90 MHz. Further, after the second reception IF signal is set to an appropriate level through the variable gain amplifier 52, the signal output from the IF signal switching switch 38 is similar to the reception at the time of the reception band Ar. Is divided by 2 by frequency divider 2 (3 9), output from demodulation wave switch 40, and further divided by 2 to 0 °. The signal having a phase of 90 ° is mixed with a demodulator 53 to be demodulated into a baseband signal.

At the time of transmission during the transmission van KBt, the signal of the high-frequency variable frequency oscillator uses a frequency 5 MHz lower than that at the time of reception (135 to 1425 MHz). This high-frequency variable frequency oscillator signal is obtained by dividing the signal of the high-frequency oscillator 36 by 3 with the frequency divider 1 (3 7), and outputting the signal from the IF signal switching switch 38 (frequency 360 MHz). And a transmission system mixer 6 (single-side band mixer 102) to select the high sideband to obtain a carrier for transmission (frequency 1710 to 1785MHz). Can be. The baseband signal is quadrature-modulated with this carrier, and is output from the driver amplifier 14 for the transmission band Bt to obtain the transmission signal.

According to the sixth embodiment, the processing of the high-frequency signal required for the transmission and reception of the dual band can be configured with a minimum number of blocks, and in addition to the two reception bands Ar and Br, However, since the reception intermediate frequency is the same, the configuration of the reception system after the reception mixer 3 can be simplified. Also, a dual-band communication device can be realized with two oscillators. Furthermore, according to the configuration of the sixth embodiment, it is possible to suppress the appearance of unnecessary waves on the reception band regardless of which band is being transmitted.

(Embodiment 7)

Next, a seventh embodiment of the present invention will be described.

The frequency range of one transmission band At and the reception band Ar is 880 to 915 MHz and 925 to 960 MHz, and the other transmission band KBt and the frequency of the reception band Br The dual-band transceivers with the ranges of 1710 to 1785 MHz and 1805 to 188 MHz are configured as shown in Figure 7.

Note that the actual transceiver device includes the transmission and reception processing circuit shown in Fig. 7. An antenna, a communication band switching switch, a transmission / reception switching switch, a power amplifier, and the like are required as 16 and 17.

The configuration of the communication apparatus, setting of the intermediate frequency, and setting of the frequency of the high frequency variable frequency oscillator 5 which are features of the seventh embodiment will be described below.

The frequency difference between the two receiving bands is from 880 MHz (= 1 fBr1-fAr1I) to 92 MHz (= IfBr2-fAr2I). Therefore, it is preferable to select a frequency between 440 MHz and 460 MHz as the reception IF frequency. It is also preferable to select a frequency close to the difference between the frequency of the reception band and the frequency of the transmission band as the frequency of the second reception IF signal.

Below, the IF frequency for reception is 450 MHz, the IF frequency for second reception is 90 MHz, the frequency of IF oscillator A (8) used for transmission band At is 495 MHz, and the reception band is The case where the frequency of the IF oscillator B (9) used for A r, the transmission band B t, and the reception band B r is set to 36 OMHz is described. At this time, the frequency of the high-frequency variable frequency oscillator 5 is set at 135 to 140 MHz.

The receiving mixers 42 and 43 are double-balanced mixers. The receiving mixer 42 for the receiving band Ar and the receiving mixer 43 for the receiving band KBr are provided separately. As the receiving system, a double super-heterodyne system is used, and the second intermediate receiving frequency is 9 OMHz. A single-sideband mixer 102 (see Fig. 3) is used as the transmission mixer 6. The configuration of this single-side band mixer is the same as in Fig. 3.

In the dual-band transceiver configured as shown in FIG. 7, the operation when the transmission band and the reception band are At, Ar, Bt, and Br is as follows.

At the time of reception in the reception band Ar, the low-noise amplifier 1 for the reception band Ar is used. The signal (925 to 960 MHz) output from the high frequency variable frequency oscillator 5 (1 375 to 375 MHz) is sufficiently attenuated by the band-limiting filter 45, and then is sufficiently attenuated by the band-limiting filter 45. By mixing with 1410 MHz), it becomes a signal of IF frequency (45 OMHz). The received IF signal is filtered by an IF oscillator B (9) (360 MHz) output from the IF signal switching switch 7 and an IF reception mixer 33 after removing unnecessary waves by a band limiting filter 51. The mixed signal becomes the second received IF signal of 90 MHz. Further, the second received IF signal has an appropriate level through the variable gain amplifier 52 and then has a phase of 0 ° and 90 ° obtained by dividing the signal of the IF oscillator B output from the IF signal switching switch 7 by four. The signal is demodulated into a baseband signal by mixing with the demodulator 53.

At the time of transmission in the transmission band At, the signal of the high-frequency variable frequency oscillator 5 uses the same frequency (1375 to 1410 MHz) as that at the time of reception. This high frequency variable frequency oscillator signal is mixed with the signal of IF oscillator A (8) (495 MHz) output from the IF signal switching switch 7 in the transmission system mixer 6 (single side band mixer 102). By selecting the lower sideband, a carrier wave for transmission (frequency 880 to 915 MHz) can be obtained. The baseband signal is quadrature-modulated with this carrier wave, and output from the transmission band At driver amplifier 12 to obtain a transmission signal.

On the other hand, at the time of reception at the reception van KBr, the signal (1805 to 1880 MHz) output from the low-noise amplifier 13 for the reception van KBr sufficiently converts the image signal with the band-limited filter 46. After being attenuated, the signal is mixed with the signal (1355 to 1430 MHz) of the high-frequency variable frequency oscillator 5 by the reception mixer 43 for the reception band Br to be a signal of the IF frequency (450 MHz). The subsequent signal processing method is exactly the same as that for reception in the reception band Ar. At the time of transmission during the transmission van KBt, the signal of the high-frequency variable frequency oscillator 5 uses a frequency 5 MHz lower than that at the time of reception (1350 to 14425 MHz). This high-frequency variable frequency oscillator signal is mixed with the signal of IF oscillator B (9) (36 OMHz) output from IF signal switch 7 by transmission mixer 6 (single-side band mixer 102). By selecting the high sideband, a carrier for transmission (frequency 1710 to 1785 MHz) can be obtained. The baseband signal is quadrature-modulated with this carrier, and output from the transmission band Bt driver amplifier 14 to obtain a transmission signal.

In general, in the configuration of FIG. 7, if the frequency of the second received IF signal is f, it is preferable that the frequency of the IF oscillator B (9) is 4ί and the frequency of the first received IF signal is 5 f .

According to the seventh embodiment, the processing of high-frequency signals required for dual-band transmission and reception can be configured with minimum blocks, and in addition to the two reception bands Ar and Br, Since the reception intermediate frequency is the same, the configuration of the reception system after the IF reception mixer 33 can be simplified. Also, a dual-band communication device can be realized with three oscillators. Further, according to the configuration of the seventh embodiment, it is possible to suppress the appearance of unnecessary waves on the reception band regardless of which band is being transmitted. Industrial applicability

As described above, according to the present invention, a low-power semiconductor device compatible with dual band can be realized. This makes it possible to provide a small, lightweight, and low-cost communication device.

Claims

The scope of the claims

1. A first set including a pair of transmit bands At (frequency range: ίAt1 to ίAt2) and a receive band Ar (frequency range: fAr1 to fAr2) A communication band and a second communication band including a pair of transmission vans KBt (frequency range: fBtl to fBt2) and a reception band KBr (frequency range: fBr1 to fBr2). A communication device having a command,

An intermediate frequency oscillating unit that outputs a signal having a first oscillation frequency and a second oscillation frequency to form the first and second communication bands; and the first and second oscillation frequencies. Modulating means for forming the transmission band At and the transmission band KBt by a direct modulation method in response to a signal having

A communication device comprising:

2. The method according to claim 1, wherein the transmission band At is 880 to 915 MHz, the reception band Ar is 925 to 960 MHz, and the transmission band B is 1710 to 1785 MHz, A communication device, wherein the reception band Br is 1805 to 1880 MHz.

3. In claim 1,

A variable frequency oscillator that outputs a signal having an oscillation frequency intermediate between the two reception bands;

The output of the first fixed frequency oscillator and the output of the second fixed frequency oscillator An oscillator switching switch for switching,

A second phase shift circuit that converts a signal output from the oscillator switching switch into a signal having a phase difference of 0 ° and 90 °,

A phase switch circuit that switches a combination of output signals of the first phase shift circuit to (0 °, 190 °) or (90 °, 0 °) according to a communication band to be used. When,

A communication device, comprising: a first addition circuit that inputs a signal output from the first mixer circuit.

4. The communication device according to claim 3, wherein the variable frequency oscillator covers a range of 133 to 145 MHz.

5. The communication device according to claim 1, wherein the first oscillation frequency is 460 to 540 MHz, and the second oscillation frequency is 360 to 380 MHz.

6. In Claim 3,

A first switch circuit that switches a reception signal having a reception frequency in the first communication band and a reception signal having a reception frequency in the second communication band as a reception signal of the communication device; ,

A first reception mixer circuit that inputs a signal output from the first switch circuit and a signal output from the variable frequency oscillator;

A communication device comprising:

7. In claim 3, additionally: A second reception mixer circuit that inputs a reception signal having a reception frequency in the first communication band and a signal output from the variable frequency oscillator; and a reception signal having a reception frequency in the second communication band. A third reception mixer circuit for inputting a signal output from the variable frequency oscillator; a signal output from the second reception mixer circuit; and a signal output from the third reception mixer circuit. And a second switch circuit for switching the received signal as a reception intermediate frequency signal of the communication device.

A communication device comprising:

8. In claim 6 or 7,

A second fixed frequency oscillator having a frequency different from that of the signal output from the first reception mixer circuit or the signal output from the second switch circuit;

A first IF receiving mixer, or a first IF receiving mixer that inputs a signal output from the second switch circuit and a signal output from the fixed frequency oscillator,

A first phase converter that divides a signal output from the fixed frequency oscillator by four and outputs a signal having a phase difference of 0 ° and 90 °;

A first demodulator that demodulates a signal output from the first IF reception mixer with a signal output from the first phase converter.

A communication device comprising:

9. In Claim 8, the transmission band At is 880 to 915 MHz, the reception band Ar is 925 to 960 MHz, and the transmission band Bt is 1710 11785 MHz, the receiving band B force 1805 to 188 MHz, and the signal output from the first receiving mixer circuit or the second switch circuit. A communication device, wherein the frequency of the first fixed frequency oscillator is 4 × f1Z5 when the frequency is f1.

10 0. In Claim 6 or 7,

A second demodulator that demodulates a signal output from the second IF reception mixer with a signal output from the second phase converter.

A communication device comprising:

1 1. In claim 10, the transmission band At is 880-915 MHz, the reception band Ar is 925-960 MHz, and the transmission band Bt is 1710- 1 785 MHz, the reception band B force is 1805 to 188 MHz, and the frequency of the signal output from the first reception mixer circuit or the second switch circuit is A communication device wherein the frequency of the second fixed frequency oscillator is 8 × f 2/7 when f 2 is set.

1 2. In claim 6 or 7,

A third IF reception mixer that inputs the signal output from the first reception mixer or the signal output from the second switch circuit and the signal output from the first IF signal switching switch;

If the signal output from the frequency divider 1 is a signal after frequency division by two, frequency division is performed by three, If the signal is divided by 3, the frequency divider 2 divides by 2, and

The signal output from the demodulation wave switching switch is frequency-divided by 2, and 0 ° and 9

A divide-by-2 phase converter for converting to a signal having a phase difference of 0 °

A communication device comprising:

13. The communication device according to claim 12, wherein an oscillation frequency of the high-frequency oscillator is 1,080 MHz.

1 4. The method according to any one of claims 8, 10 and 12, wherein the transmission band At is 880 to 915 MHz, the reception band Ar is 925 to 960 MHz, and the transmission band Bt. Power Sl 7 10 ~ 1 785MHz, the receiving band Br force? 1805 to 1880 MHz, and the frequency of a signal output from any one of the first IF reception mixer to the third IF reception mixer is the reception frequency of the two communication bands. Transmission frequency difference (I f Ar 1-f At 1 1 = 1 f Ar 2-f At 2) I f B rl-f B tl 1 = If B r 2-f B t 2 I A communication device characterized by being between 45 and 95 MHz.

1 5. A first communication band including a pair of transmission bands At (frequency range: fAtl to fAt2) and reception bands Ar (frequency range: fAr1 to fAr2). And a second communication van including a pair of transmitting vans Bt (frequency range: fBtl to iBt2) and receiving van KBr (frequency range: fBr1 to fBr2). A communication device having a

A high-frequency oscillator,

Divide the signal output from the high-frequency oscillator by 2 or 3 Peripheral

A transmission mixer having a signal output from the IF signal switching switch and a signal output from a high frequency variable frequency oscillator as inputs,

A communication device comprising:

16. In Claim 15, the transmission band At is 880 to 915 MHz, the reception band Ar is 925 to 960 MHz, and the transmission band Bt power? 1710 ~ 1 785MHz, the receiving band Br force? A communication device having a frequency of 1805 to 1880 MHz and outputting a signal having a frequency of 1080 MHz from the high-frequency oscillator.

17. The method of claim 15, wherein the transmission band At is 880-915 MHz, the reception band Ar is 925-96 OMHz, and the transmission band KBt is 1710-1785 MHz, A communication device, wherein the reception band Br is 1805 to 1880 MHz, and the high-frequency variable frequency oscillator covers a range of 1330 to 1455 MHz.

18. The communication device according to any one of claims 1 to 17, wherein the communication device executes communication using an FDD (frequency division duplex) or TDMA (time division multiple access) communication method.

1 9. The communication device according to any one of claims 1 to 17, wherein the communication device is used as a transceiver device.

20. A first communication band including a pair of transmission bands At (frequency range: fAtl to fAt2) and reception bands Ar (frequency range: ίAr1 to fAr2). And a second communication including a pair of transmitting vans KBt (frequency range: fBtl to fBt2) and a receiving van Br (frequency range: fBr1 to fBr2). An intermediate frequency input terminal for inputting a signal having a first oscillation frequency and a second oscillation frequency to form a band;

A transmission mixer that receives as input a signal output from the intermediate frequency signal switching switch and a signal output from a high frequency variable frequency oscillator;

A transmission signal switching switch for allocating and outputting a signal output from the quadrature modulator in accordance with a transmission band;

A reception signal switching switch for selecting any one of the reception bands A r and B r,

A semiconductor device comprising:

21. In Claim 20, the transmission band At is 880 to 910 MHz, the reception band Ar is 925 to 960 MHz, and the transmission band Bt is 17. 10. A semiconductor device, wherein the receiving band Br is in the range of 180 to 180 MHz.

22. In Claim 20, wherein the transmission system mixer comprises:

The signals output from the high-frequency variable frequency oscillator are phased at 0 ° and 90 °. A first phase shift circuit for converting to a signal having a difference,

A second phase shift circuit for converting a signal output from the intermediate frequency signal switching switch into a signal having a phase difference between 0 ° and 90 °;

A phase switch circuit that switches a combination of output signals of the first phase shift circuit to (0 °, 90 °) or (90 °, 0 °) according to a communication band to be used. When,

23. The semiconductor device according to claim 20, wherein the frequency of the signal output from the high-frequency variable frequency oscillator covers a range of 133 to 14455 MHz.

24. The semiconductor device according to claim 20, wherein the first oscillation frequency is 460 to 540 MHz and the second oscillation frequency is 360 to 380 MHz. .

2 5. A reception signal switching switch according to claim 20;

Instead of the reception mixer, a reception mixer A that receives the signal of the reception band Ar, a reception mixer B that receives the signal of the reception band Br, and an output signal from the reception mixers A and B is selectively output A second reception signal switching switch.

2 6. In claim 20 or 25, in addition,

A semiconductor device, comprising: an IF reception mixer provided in a stage preceding the demodulator; and an output from the intermediate frequency signal switching switch being input to the IF reception mixer.

27. First communication including a pair of transmission bands At (frequency range: fAt1 to fAt2) and reception bands Ar (frequency range: fAr1 to fAr2) A second band including a pair of transmission vans Bt (frequency range: fBtl to iBt2) and a reception van KBr (frequency range: fBr1 to ίBr2). An input terminal for inputting a signal having a fixed oscillation frequency to form a communication band;

A reception signal switch _ switch for selecting any one of the reception bands A r and Br;

A reception mixer that receives a signal output from the reception signal switching switch and a signal output from the high frequency variable frequency oscillator as inputs,

A signal output from the IF signal switching switch; and an IF reception mixer that inputs a reception intermediate frequency signal output from the reception mixer.

A frequency divider 2 that divides the signal output from the IF signal switching switch by 3 if the signal is divided by 2 and divides the signal by 2 if the signal is divided by 3; A demodulation wave switching switch for selecting the output of the frequency divider 2; and a divide-by-2 signal for dividing the signal output from the demodulation wave switching switch into two signals having a phase difference of 0 ° and 90 °. A circumferential phase converter;

A demodulator for demodulating a signal output from the IF reception mixer with a signal output from the divide-by-2 phase converter;

A semiconductor device comprising:

28. The semiconductor device according to claim 27, wherein the fixed oscillation frequency is 108 OMHz.

29. The claim 27, wherein the transmit band At is 880-915 MHz, the receive band Ar is 925-960 MHz, and the transmit band Bt is 1710. ：: L785 MHz, the semiconductor device characterized in that the receiving band Br is 1805-1880 MHz.

30. The semiconductor device according to claim 27, wherein the frequency of the signal output from the high-frequency variable frequency oscillator covers a range of 130 to 144 MHz.

3 1. In Claim 20, In addition,

A semiconductor device comprising a variable gain amplifier provided before the demodulator;

3 2. In Claim 27, in addition,

3 3. In claim 20, in addition,

A semiconductor device, wherein driver amplifiers corresponding to respective transmission bands are provided at a subsequent stage of the transmission signal switching switch.

3 4. In Claim 27, in addition, A semiconductor device, wherein driver amplifiers corresponding to respective transmission bands are provided at a subsequent stage of the transmission signal switching switch.