JP4923659B2 - Local oscillation device and radio transceiver using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a local oscillator which is excellent in frequency stability and phase noise property. <P>SOLUTION: The local oscillator outputs at least two local oscillation signals which are inputted to a predetermined signal processing means, and is provided with a first oscillation means generating a first local oscillation signal which is a fixed frequency, and a second oscillation means generating a second local oscillation signal which is a variable frequency. The second oscillation means receives the first local oscillation signal, and outputs the second oscillation signal which corrects the variation of the first local oscillation signal. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a local oscillation device, and more particularly to a local oscillation device that outputs two or more local oscillation signals. The present invention also relates to a radio transceiver using this local oscillator.

  In recent years, as communication devices using wireless transmission such as mobile phones and wireless local area networks (LANs) have become widespread, the number of wireless stations has increased rapidly. In addition, as broadband information communication becomes common in these applications, the occupied frequency band per wave is expanded. As a result, frequency resources are consumed at a rate corresponding to the product of the number of radio stations and the occupied frequency band, and the problem of depletion is occurring.

  As a method for avoiding the above-described depletion of frequency resources, first, improvement of frequency utilization efficiency can be mentioned. This means that the signal transmission capacity per unit frequency band is increased. For this purpose, it is necessary to increase the accuracy of the signal and identify the signal with high resolution at the time of reception. For example, in a commonly used digital modulation scheme, the amplitude, frequency, or phase of a carrier wave is modulated with a discrete value at the time of transmission. In order to increase the amount of information that can be transmitted simultaneously by narrowing the interval between the discrete values, the carrier wave used In addition, high accuracy is required for the frequency and phase of the local oscillation signal. In other words, high frequency stability and low phase noise characteristics are desired. Also, at the time of reception, high frequency stability and low phase noise characteristics are required for the local oscillation signal and the carrier wave in order to avoid deterioration of the reception signal due to the local oscillation signal and carrier wave generated by the frequency converter and demodulator.

  On the other hand, as another method for avoiding the depletion of frequency resources, the use of a high frequency band, which has conventionally been difficult to use technically, has been studied. In this method, a baseband signal is modulated with a very high frequency carrier wave such as a microwave or a millimeter wave and transmitted. In the past, devices that could be used reasonably in terms of performance, price, size, etc. in these bands were limited, and they were used less because they were shorter than when using a frequency band with a low signal transmission distance. However, recently, due to the advancement of device technology and an increase in demand for communication over a relatively short distance such as a wireless LAN, utilization of these bands is desired.

  However, in general, an oscillator that generates a carrier wave has a higher phase fluctuation, that is, a higher phase noise level when the oscillation frequency is higher when the same configuration is used. Therefore, also in this case, high frequency stability and low phase noise characteristics are required for the carrier wave and the local oscillation signal.

  Therefore, conventionally, a PLL (Phase Locked Loop) technique has been used in order to obtain high frequency stability and low phase noise characteristics. Here, a first conventional example of a wireless transmission / reception apparatus using a PLL disclosed in Non-Patent Document 1 below will be described with reference to FIG. The wireless transmission / reception apparatus according to the first example is equipped with double conversion type frequency converters 502 and 503 using two frequency mixers for frequency conversion in each of the transmission system and the reception system.

  First, as shown in FIG. 16, the received radio signal received by the antenna 505 is subjected to processing such as amplification and signal selection by a filter in the high frequency processing unit 501, and then received frequency conversion unit 502 as a received high frequency signal S52a. Is input. The transmission high-frequency signal S53a output from the transmission frequency conversion unit 503 is subjected to processing such as unnecessary wave removal and amplification by a filter in the high-frequency processing unit 501, and then transmitted from the antenna 505 as a transmission radio signal.

  The reception frequency conversion unit 502 inputs the reception high-frequency signal S52a, the first reception local oscillation signal S54a and the second reception local oscillation signal S54b generated by the local oscillation unit 504. The reception high-frequency signal S52a is mixed with the first reception local oscillation signal S54a by the first reception frequency mixer 521 to generate an output S52b. The output S52b is input to the filter 522, and after an unnecessary wave such as an image signal is removed, the output S52b becomes the first reception intermediate frequency signal S52c.

  Subsequently, the first reception intermediate frequency signal S52c is mixed with the second reception local oscillation signal S54b by the second reception frequency mixer 523, and an output S52d is generated. The output S52d is input to the filter 524, and after unnecessary waves such as an image signal are removed, the output S52d becomes the second reception intermediate frequency signal S52e. The second reception intermediate frequency signal S52e is output from the reception frequency conversion unit 502 as a reception intermediate frequency signal (reception IF signal).

  On the other hand, the transmission frequency conversion unit 503 receives the transmission intermediate frequency signal (transmission IF signal), the first transmission local oscillation signal S54d and the second transmission local oscillation signal S54c generated by the local oscillation unit 504. At this time, the transmission IF signal is input to the transmission frequency conversion unit 503 as the first transmission intermediate frequency signal S53d. Then, the first transmission intermediate frequency signal S53d is mixed with the first transmission local oscillation signal S54d by the first transmission frequency mixer 533, and an output S53c is generated. The output S53c is input to the filter 532, and after an unnecessary wave such as an image signal is removed, the output S53c becomes the second transmission intermediate frequency signal S53b. The second transmission intermediate frequency signal S53b is mixed with the second transmission local oscillation signal S54c by the second transmission frequency mixer 531 to generate a transmission high frequency signal S53a and output from the transmission frequency conversion unit 503. .

  Next, the local oscillation unit 504 will be described. The local oscillating unit 504 includes a reference signal generator 541. This becomes a frequency reference and phase reference of a PLL circuit described later, and has high frequency stability and low phase noise characteristics. An example is a crystal oscillator with a temperature compensation function for frequency. Then, the first reception local oscillation signal S54a is generated by the PLL circuit using the output of the reference signal generator 541 as a reference signal.

  In this conventional example, the PLL circuit that generates the first reception local oscillation signal S54a includes a voltage controlled oscillator (VCO) 551, a loop amplifier 552, a VCO output signal divider 553, a frequency phase comparator 554, a reference signal divider. The device 555 is configured. First, the output S54a of the VCO 551 is not only output as the first reception local oscillation signal S54a but also input to the VCO output signal frequency divider 553, and is divided. On the other hand, the reference signal generated by the reference signal generator 541 is input to the reference signal frequency divider 555 and divided. The outputs of the VCO output signal frequency divider 553 and the reference signal frequency divider 555 are input to the frequency phase comparator 554. The frequency phase comparator 554 compares these frequencies and phases to generate an error signal. This error signal is input to the loop amplifier 552, and after being given a loop frequency characteristic, it is fed back to the VCO 551 as a frequency control voltage.

  As a result, the output S54a of the VCO 551 obtains the same frequency stability as the reference signal, and at the same time enjoys the phase noise suppression effect within the loop band. Further, by selecting an appropriate value for the frequency dividing number of the VCO output signal frequency divider 553 and the reference signal frequency divider 555, the frequency of the phase synchronization of the output S54a of the VCO 551 can be changed.

  Similarly, the PLL circuit that generates the second reception local oscillation signal S54b includes a VCO 556, a loop amplifier 557, a VCO output signal frequency divider 558, a frequency phase comparator 559, and a reference signal frequency divider 560. The PLL circuit that generates the first transmission local oscillation signal S54d on the transmitter side includes a VCO 566, a loop amplifier 567, a VCO output signal frequency divider 568, a frequency phase comparator 569, and a reference signal frequency divider 570. The Further, the PLL circuit that generates the second transmission local oscillation signal S54c on the transmitter side is composed of a VCO 561, a loop amplifier 562, a VCO output signal frequency divider 563, a frequency phase comparator 564, and a reference signal frequency divider 565. The Explanation of these operations is omitted.

  In this conventional example, the high frequency processing unit 501 has the same configuration as that used in the WCDMA portable terminal. The antenna 505 is shared for transmission and reception, and a reception radio signal and a transmission radio signal are superimposed on a radio signal S51 transmitted and received there. The received radio signal in the radio signal S51 is guided to the low noise amplifier 511 by the duplexer 515 and amplified there, and then a required frequency component is extracted by the filter 513 and output as the received high frequency signal S52a. Further, the transmission high-frequency signal S53a is filtered with an unnecessary wave by a filter 514, amplified by an amplifier 512, and then superimposed on the radio signal S51 by a duplexer 515 as a transmission radio signal.

  As a similar form of the conventional example of the wireless transmission / reception apparatus using the first PLL, there is a form in which the first reception local oscillation signal is used as the second transmission local oscillation signal. That is, as shown in FIG. 17, the first reception local oscillation signal S54a is input to the second transmission frequency mixer 531 of the transmission frequency conversion unit 503 as the second transmission local oscillation signal. In this case, compared with the case of FIG. 16, the VCO 561, the loop amplifier 562, the VCO output signal frequency divider 563, the frequency phase comparator 564, and the reference signal frequency divider 565 are unnecessary.

  Next, a second conventional example of a wireless transmission / reception apparatus using a PLL disclosed in Non-Patent Document 2 below will be described with reference to FIG. The wireless transmission / reception apparatus in this conventional example has a single conversion type frequency conversion function using one modulator and a frequency converter for the transmission system and one frequency converter and a demodulator for the reception system. Equipped with 602,603.

  First, the received radio signal received by the antenna 605 is subjected to processing such as amplification and signal selection by a filter in the high frequency processing unit 601, and then input to the reception demodulation unit 602 as a received high frequency signal S62a. In addition, the transmission high-frequency signal S63a output from the transmission modulation unit 603 is transmitted from the antenna 605 after being subjected to processing such as unnecessary wave removal and amplification by a filter in the high-frequency processing unit 601.

  Next, the reception demodulation unit 602 receives the reception high-frequency signal S62a, the reception local oscillation signal S64a generated by the local oscillation unit 604, and the demodulation carrier signal S64b. The reception high frequency signal S62a is mixed with the reception local oscillation signal S64a by the reception frequency mixer 621, and an output S62b is generated. The output S62b is input to the filter 622 and unnecessary waves are removed, and then becomes the reception intermediate frequency signal S62c. The reception intermediate frequency signal S62c is mixed with the demodulation carrier signal S64b by the demodulator 623, and an output S62d is generated. The output S62d is input to the filter 524, and after unnecessary signal components are removed, the output S62d becomes the reception baseband signal S62e. The reception baseband signal S62e is output from the reception demodulation unit 602 as a reception baseband signal (reception BB signal).

  On the other hand, the transmission modulation unit 603 receives the transmission baseband signal (transmission BB signal), the transmission carrier signal S64d and the transmission local oscillation signal S64c generated by the local oscillation unit 604. The transmission BB signal is input to modulation section 603 as transmission baseband signal S63d. The transmission baseband signal S63d modulates the transmission carrier signal S64d by the modulator 633, and an output S63c is generated. The output S63c is input to the filter 632 and unnecessary waves are removed, and then becomes the transmission intermediate frequency signal S63b. The transmission intermediate frequency signal S63b is mixed with the transmission local oscillation signal S64c by the transmission frequency mixer 631 to generate the transmission high frequency signal S63a and output from the transmission modulation unit 603.

  Next, the local oscillation unit 604 will be described. The local oscillator 604 includes a reference signal generator 641. Then, using the output of the reference signal generator 641 as a reference signal, a reception local oscillation signal S64a is generated by the PLL circuit.

  The PLL circuit that generates the reception local oscillation signal S64a in this conventional example includes a VCO 651, a loop amplifier 652, a VCO output signal frequency divider 653, a frequency phase comparator 654, and a reference signal frequency divider 655. Similarly, the PLL circuit that generates the demodulation carrier signal S64b includes a VCO 656, a loop amplifier 657, a VCO output signal frequency divider 658, a frequency phase comparator 659, and a reference signal frequency divider 660. The PLL circuit that generates the modulation carrier signal S64d includes a VCO 666, a loop amplifier 667, a VCO output signal frequency divider 668, a frequency phase comparator 669, and a reference signal frequency divider 670. Further, the PLL circuit that generates the transmission local oscillation signal S64c includes a VCO 661, a loop amplifier 662, a VCO output signal frequency divider 663, a frequency phase comparator 664, and a reference signal frequency divider 665.

  In addition, the high frequency processing unit 601 in the conventional example has the same configuration as that of the first conventional example. That is, in the high frequency processing unit 601, the antenna 605 is shared for transmission and reception, and the reception radio signal and the transmission radio signal are superimposed on the radio signal S61 transmitted and received there. The received radio signal in the radio signal S61 is guided to the low noise amplifier 611 by the duplexer 615 and amplified there, and then a required frequency component is extracted by the filter 613 and output as a received high frequency signal S62a. The transmission high-frequency signal S63a is filtered with an unnecessary wave by the filter 614, amplified by the amplifier 612, and then superimposed on the radio signal S61 by the duplexer 615 as a transmission radio signal.

  The transceiver configured in this way basically has the same configuration as that of the first conventional example described above, and operates in the same manner as described above. That is, the output S64a such as the VCO 651 used in the reception demodulation unit 602 or the transmission modulation unit 603 obtains the same frequency stability as the reference signal, and at the same time enjoys the phase noise suppression effect in the loop band. Further, by selecting appropriate values for the frequency dividing numbers of the VCO output signal divider 653 and the reference signal divider 655 and the like, the frequency of the phase synchronization of the output S64a of the VCO 651 and the like can be changed.

  As a similar form of the conventional example of the wireless transmission / reception apparatus using the second PLL, there is a form in which the reception local oscillation signal is used as the transmission local oscillation signal. That is, as shown in FIG. 19, the reception local oscillation signal S64a is input to the transmission frequency mixer 631 of the transmission frequency conversion unit 603 as a transmission local oscillation signal. In this case, the VCO 661, the loop amplifier 662, the VCO output signal frequency divider 663, the frequency phase comparator 664, and the reference signal frequency divider 665 are unnecessary as compared with the case of FIG.

Gerard Maral, Michel Bousquet, `` SATELLITE COMMUNICATINS SYSTEM (4th Edition) '', U.S.A., WILEY, May, 2002, pp.420-421, Figure 8.32, Figure 8.33 Timothy Pratt, Charles Bostian, Jeremy Allutt, `` Satellite Communication (2nd Edition) '', U.S.A., WILEY, October 18, 2002, p.108, FIGURE 4.6

  However, the above-described conventional transmission / reception apparatus has the following problems. First, since a VCO is used to generate a local oscillation signal, a modulation carrier signal, and a demodulation carrier signal, there has been a problem that phase noise characteristics are poor. This problem will be further described below.

  It is generally known that the phase noise characteristic of an oscillator strongly depends on the Q value of the resonator that determines the oscillation frequency, and that the higher the value, the easier it is to obtain a low phase noise characteristic (level). For example, when a 10 MHz oscillator is configured, a low phase noise characteristic can be obtained by using a crystal resonator as a resonator rather than using an LC resonator. Similarly, when a 10 GHz oscillator is configured, a low phase noise characteristic can be obtained by using a dielectric resonator rather than using a microstrip line resonator. On the other hand, the VCO used in the above-described conventional example has a variable reactance element such as a varactor diode in order to make the oscillation frequency voltage controllable in addition to a resonator and an active element having a gain for sustaining oscillation. And coupled to the resonator. For this reason, even if a resonator having a high Q value is coupled with a variable reactance element having a low Q value, the combined Q value of the resonator is lowered. As a result, the variable reactance constituted by the same resonator is reduced. The phase noise characteristics of the VCO are degraded compared to an oscillator in which no elements are coupled. Further, it is generally known that the phase noise characteristic of an oscillator becomes worse as the oscillation frequency is higher. For these reasons, each of the two conventional examples described above has two VCOs for each transmission / reception system, but the phase noise characteristic of the higher frequency is dominant in the phase noise characteristic of the transmission / reception apparatus. It becomes the target.

  Furthermore, since the PLL is a negative feedback system, there is a limit to the frequency band in which response is possible (response speed that the negative feedback system can follow), and it is within this frequency band that the PLL can suppress phase noise. Therefore, the influence of the above-described phase noise characteristic appears remarkably in the carrier vicinity phase noise characteristic outside the loop band where there is no suppression effect by the PLL. On the other hand, the deterioration cannot be avoided even in the loop band.

  The above-described deterioration of the phase noise characteristic (level) causes an increase in error rate. As a result, there are problems such as a decrease in signal transmission throughput in the transmitter / receiver, a decrease in service such as a transmission delay associated with retransmission of erroneous information, and generation of extra power consumption associated with information retransmission processing.

  In order to solve the above problem, if the oscillator dominant to the phase noise characteristic of the wireless transceiver is replaced with a non-VCO oscillator (free-running oscillator) from the VCO, the frequency stabilization effect by the PLL Cannot be obtained, resulting in a second problem of frequency stability degradation. In other words, if a free-running oscillator is used, the frequency deviation and stability required for wireless transceivers cannot be obtained due to initial deviation due to individual variations, load fluctuations, power supply voltage fluctuations, temperature fluctuations, secular changes, etc. End up.

  The third problem is that, as shown in FIGS. 16 to 19, since the conventional example requires a large number of PLL circuits, the circuit scale increases accordingly, and the shape of the transmission / reception apparatus itself is large. It will be. In particular, when a mobile communication terminal such as a mobile phone is incorporated and used, there is a problem that the terminal cannot be downsized and portability is impaired.

  Furthermore, the fourth problem is that a large number of PLL circuits are required, and power corresponding to the number of PLL circuits is consumed, resulting in an increase in power consumption. This means that when used in a battery-powered communication terminal such as a mobile phone, the duration of the battery, that is, the standby time and the call time is shortened, or the portability is increased due to the need for a heavy and large-capacity battery. It leads to deterioration. Further, in connection with the need for a large number of PLL circuits described above, there is a problem that the component cost increases and the manufacturing cost of the transmission / reception device increases.

  For this reason, the present invention aims to improve the disadvantages of the above-described conventional example, and in particular to provide a local oscillator excellent in frequency stability and phase noise characteristics. The purpose is to improve the signal transmission / reception accuracy by the wireless transceiver.

Therefore, the local oscillation device according to one aspect of the present invention is
A local oscillation device that outputs at least two local oscillation signals input to a predetermined signal processing means,
First oscillation means for emitting a first local oscillation signal having a fixed frequency, and second oscillation means for emitting a second local oscillation signal having a variable frequency,
The second oscillation means inputs the first local oscillation signal and outputs a corresponding second local oscillation signal so as to correct the change of the first local oscillation signal.
It is characterized by that.

  In particular, the second oscillating means has reference signal generating means for generating a reference signal, and the second local oscillating signal is used as the phase of the sum frequency signal of the first local oscillating signal and the second local oscillating signal. Is synchronized with the phase of the reference signal, and the frequency of the sum frequency signal is changed so as to be constant and output. For example, it is characterized in that the frequency or phase of the second local oscillation signal is increased / decreased contrary to the increase / decrease change of the frequency or phase of the first local oscillation signal.

  According to the above invention, first, the first local oscillation signal having a fixed frequency output from the first oscillation means and the second local oscillation signal having a variable frequency output from the second oscillation means are, for example, The signal is input to signal processing means such as a frequency converter of the transceiver, mixed with the transmission / reception signal, and used for the frequency conversion processing. Here, it is assumed that frequency conversion is performed by a frequency equal to the sum frequency of the first local oscillation signal and the second local oscillation signal. At this time, the first local oscillation signal output from the first oscillation means is input to the second oscillation means, and the second oscillation means corrects the change in the first local oscillation signal. A corresponding second local oscillation signal is output. For example, a second local oscillation signal that is increased / decreased contrary to the increase / decrease change of the frequency or phase of the first local oscillation signal is output. Accordingly, in the signal processing means to which the first and second local oscillation signals are input, changes in the frequency and phase of the first local oscillation signal are canceled by the second local oscillation signal. As a result, the frequency stability can be ensured, and the phase noise characteristics can be improved by the first local oscillation signal having a fixed frequency.

  The second oscillating means includes reference signal generating means for generating a reference signal, and the second local oscillating signal is changed to a phase of a difference frequency signal between the first local oscillating signal and the second local oscillating signal. Is synchronized with the phase of the reference signal, and the difference frequency signal is output so that the frequency of the difference frequency signal is constant. For example, it is characterized in that the frequency or phase of the second local oscillation signal is increased / decreased equal to the increase / decrease change of the frequency or phase of the first local oscillation signal.

  According to the above invention, first, the first local oscillation signal having a fixed frequency output from the first oscillation means and the second local oscillation signal having a variable frequency output from the second oscillation means are, for example, The signal is input to signal processing means such as a frequency converter of the transceiver, mixed with the transmission / reception signal, and used for the frequency conversion processing. Here, it is assumed that frequency conversion is performed by a frequency equal to the difference frequency between the first local oscillation signal and the second local oscillation signal. At this time, the first local oscillation signal output from the first oscillation means is input to the second oscillation means, and the second oscillation means corrects the change in the first local oscillation signal. A corresponding second local oscillation signal is output. For example, the second local oscillation signal that is increased or decreased in the same manner as the increase or decrease in the frequency or phase of the first local oscillation signal is output. Accordingly, in the signal processing means to which the first and second local oscillation signals are input, changes in the frequency and phase of the first local oscillation signal are canceled by the second local oscillation signal. As a result, the frequency stability can be ensured, and the phase noise characteristics can be improved by the first local oscillation signal having a fixed frequency.

  The second oscillating means is a negative feedback circuit including a mixing means for mixing the input first local oscillation signal and the second local oscillation signal. A PLL circuit having means. Furthermore, the first oscillating means is a free-running oscillator.

  Thus, by configuring the second oscillating means with a PLL or the like, as described above, it is possible to improve the frequency stability and reduce the phase noise level with a simple configuration. Since the use of two or more can be suppressed, the configuration of the local oscillation circuit can be further simplified. Therefore, it is possible to reduce power consumption, reduce component costs, and further reduce the size of equipment using the local oscillation device.

  Each of the oscillation means described above is provided with a frequency divider that divides each local oscillation signal output to the predetermined signal processing means by a preset frequency division number. As a result, the frequency difference between the intermediate signal generated in the second oscillating means and the signal (radio signal) subjected to frequency conversion or the like by using the local oscillation signal in the predetermined signal processing means is divided. It can be expanded several times, and these interferences can be more effectively suppressed.

  The phase noise level of the first local oscillation signal emitted from the first oscillation means is lower than the phase noise level of the second local oscillation signal emitted from the second oscillation means. Further, the frequency of the first local oscillation signal generated by the first oscillation means is at least x times that of the second local oscillation signal generated by the second oscillation means (x: shown in Formula 2). It is said. By satisfying these conditions, the phase noise characteristics can be improved more reliably.

  In addition to the first oscillating device, the local oscillating device further includes one or a plurality of other fixed frequency oscillating means for outputting a local oscillating signal having a fixed frequency to the predetermined signal processing means. The means inputs the local oscillation signal output from one or more other fixed frequency oscillation means and the first local oscillation signal output from the first oscillation means, and inputs the other fixed frequency oscillation. The second local oscillation signal corresponding to the correction of the change between the local oscillation signal from the means and the first local oscillation signal is output. At this time, the other fixed frequency oscillating means is a free-running oscillator.

  Further, the local oscillation device is further provided with one or more pairs of first oscillation means and second oscillation means for outputting each local oscillation signal to predetermined signal processing means, respectively. It is a feature.

  As described above, even if the predetermined signal processing means is configured to require further frequency conversion or the like, one or more fixed frequency oscillating means are further provided, and the local oscillation signal that is the output is provided as the predetermined signal processing means. By inputting these local oscillation signals to the second oscillation means, the frequency fluctuation of the fixed frequency oscillation means can be corrected and the frequency stability can be ensured as described above. The phase noise characteristics can be improved. Further, it is only necessary to provide at least one second oscillating means that is, for example, a PLL, and the local oscillation device can be downsized.

Further, in the present invention, the above-described local oscillation device,
Using each local oscillation signal output from the local oscillation device, a received signal processing device that performs signal processing such as frequency conversion processing and demodulation processing on the signal received from the antenna;
A receiver equipped with is provided.

  In the receiver, the reception signal processing device mixes the first local oscillation signal output from the local oscillation device with the signal received from the antenna, converts the frequency, and outputs a first intermediate frequency signal. A second frequency mixer that mixes the second local oscillation signal output from the local oscillation device with the first intermediate frequency signal, converts the frequency, and outputs a second intermediate frequency signal; It is characterized by having. Alternatively, in the receiver, the reception signal processing device includes a frequency mixer that mixes the first local oscillation signal output from the local oscillation device with the signal received from the antenna, converts the frequency, and outputs an intermediate frequency signal; And a demodulator that mixes and demodulates the second local oscillation signal output from the local oscillation device with the intermediate frequency signal and outputs a reception baseband signal.

  In the present invention, the local oscillation device described above and each local oscillation signal output from the local oscillation device are used to perform signal processing such as frequency conversion processing and modulation processing for generating a signal to be transmitted from the antenna. A transmission signal processing apparatus for performing transmission is provided.

  In the transmitter, the transmission signal processing device mixes the second local oscillation signal output from the local oscillation device with the first intermediate frequency signal, converts the frequency, and outputs the second intermediate frequency signal. 1 frequency mixer and a second frequency mixer that mixes the first local oscillation signal output from the local oscillation device with the second intermediate frequency signal, converts the frequency and outputs a transmission signal transmitted from the antenna It is characterized by having. Alternatively, in the transmitter, the transmission signal processing device includes a modulator that mixes the second local oscillation signal output from the local oscillation device with a transmission baseband signal, modulates the modulated signal, and outputs an intermediate frequency signal, and the local oscillation device And a frequency mixer that mixes the first local oscillation signal output from the output signal with an intermediate frequency signal and converts the frequency to output a transmission signal transmitted from the antenna.

  Furthermore, the present invention provides a transmitter / receiver that includes the receiver and transmitter described above, and that is configured by sharing a circuit between the local oscillator that forms the receiver and the local oscillator that forms the transmitter. ing. At this time, the first oscillation means in the local oscillation device constituting the receiver and the first oscillation means in the local oscillation device constituting the transmitter are configured to share the same oscillation means. It is characterized by. As a result, it is possible to reduce the size of the transmitter / receiver, reduce the cost of components, and reduce power consumption.

  And, by installing the above-described receiver, transmitter, and transceiver in a communication device, for example, a mobile phone terminal, it is excellent in frequency stability as described above, and can realize low phase noise characteristics, A small device can be configured.

  Since the present invention is configured and functions as described above, according to this, in the signal processing means using the local oscillation signal output from the local oscillation device, it is possible to ensure the frequency stability and at the same time the phase noise. The characteristics are improved, that is, the phase noise level can be reduced, and a high-performance transceiver can be configured.

  The local oscillation device characterized by the present invention is used in a transceiver such as a mobile phone terminal, for example. In the following description, a transceiver that performs processing using two or more local oscillation signals in order to frequency-convert, modulate, and demodulate a high frequency to a low frequency that can be easily processed will be described as an example.

  A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a circuit diagram showing the configuration of the present invention, and FIGS. 2 to 3 are explanatory diagrams showing the operation of the circuit.

  The transmitter / receiver in the present embodiment shown below first receives a high-frequency (for example, 12 GHz) signal on the receiver side, and mixes the first local oscillation signal (for example, 9 GHz) with this to convert the frequency. Then, a first intermediate frequency signal (for example, 3 GHz) is obtained. Further, this is mixed with a second local oscillation signal (for example, 2 GHz) and frequency-converted to obtain a second intermediate frequency signal (for example, 1 GHz). Further, on the transmitter side, the second local oscillation signal is mixed with the signal to be transmitted having a low frequency to convert the frequency to obtain an intermediate frequency signal, and the first local oscillation signal is further mixed with this to the high frequency. To obtain a transmission signal to be transmitted from the antenna. Thus, the transceiver in the present embodiment adopts a configuration (double superheterodyne system) that performs frequency conversion twice. In the following, an apparatus configured as a transceiver will be described, but a transmitter and a receiver may be configured separately.

[Constitution]
As shown in FIG. 1, the radio transceiver according to the present embodiment processes an antenna 5, a high frequency processing unit 1 connected to the antenna 5, a reception frequency converting unit 2 that processes a reception signal, and a transmission signal. A transmission frequency conversion unit 3 and a local oscillation unit 4 (local oscillation device) that generates a local oscillation signal are provided.

  First, the local oscillating unit 4 includes a fixed frequency oscillator 41 (first oscillating means) that outputs a first local oscillating signal that is a fixed frequency signal. The fixed frequency oscillator 41 is a free-running oscillator, for example, a dielectric oscillator. Then, the first local oscillation signal (reference S41 in FIG. 2) which is an output from the fixed frequency oscillator 41 is input to the first frequency mixer 21 of the reception frequency converter 2 described later, and the second This is input to the frequency mixer 51 provided in the oscillation circuit 42.

  The fixed frequency oscillator 41 is also shared on the transmitter side, and a first local oscillation signal (reference S41 in FIG. 2) that is an output from the fixed frequency oscillator 41 is a first frequency for the transmission frequency conversion unit 3 described later. Is input to the second frequency mixer 31 as a local oscillation signal. Further, the fixed frequency oscillator 41 is also input to a frequency mixer 61 provided in the second oscillation circuit 43 on the transmitter side.

  Further, the local oscillation unit 4 includes second oscillation circuits 42 and 43 (first frequency outputs) that output variable frequency local oscillation signals, which are second local oscillation signals, to the reception frequency conversion unit 2 and the transmission frequency conversion unit 3, respectively. 2 oscillation means). First, the configuration of the circuits 42 and 43 will be described by taking the receiver side as an example.

  The second oscillation circuit 42 shown in FIG. 2 is a negative feedback circuit, and constitutes a PLL circuit having a reference signal generator 50 and a VCO 53 that outputs a variable frequency local oscillation signal. Specifically, the reference signal generator 50, a reference signal divider 57 to which the output of the reference signal generator 50 is input, a VCO output signal divider 55 that divides the output from the VCO 53, A frequency phase comparator 56 that compares the divided output with the divided output from the reference signal frequency divider 57, and a loop amplifier that inputs an error signal from the frequency phase comparator 56 and outputs a frequency control signal to the VCO 53. 54. Further, the present embodiment includes a frequency mixer 51 that mixes the output of the VCO 53 and the output from the fixed frequency oscillator 41, and a filter 52 that filters the mixed output. This is input to the VCO output signal frequency divider 55. Then, the output from the VCO 53 is input to the second frequency mixer 23 of the reception frequency converter 2 described later as a reception variable frequency local oscillation signal (reference S55 in FIG. 2) which is a second local oscillation signal. The

  Further, the transmitter-side second oscillation circuit 43 (see FIG. 3) provided in the local oscillator 4 also has substantially the same configuration as the receiver-side second oscillation circuit 42. That is, a PLL circuit having a VCO 63 that outputs a variable frequency local oscillation signal is configured, and a frequency mixer 61 that mixes the output from the VCO 63 and the fixed local oscillation signal output from the fixed frequency oscillator 41, and this mixing A filter 62 that filters the output, a VCO output signal divider 65 that divides the output from the filter 62, a reference signal divider 67 that receives the output of the reference signal generator 50, A frequency phase comparator 66 that compares the frequency output and the frequency-divided output from the VCO output signal frequency divider 65; a loop amplifier 64 that inputs an error signal from the frequency phase comparator 66 and outputs a frequency control signal to the VCO 63; It is equipped with. Then, the output from the VCO 63 is input to the first frequency mixer 33 of the transmission frequency converter 3 described later as a transmission variable frequency local oscillation signal (reference S65 in FIG. 3) which is a second local oscillation signal. .

  Next, the high frequency processing unit 1 will be described. The high frequency processing unit 1 includes a duplexer 15 connected to the antenna 5, a low noise amplifier 11 and a filter 13 connected to the reception frequency conversion unit 2 side, and a power amplifier 12 and a filter connected to the transmission frequency conversion unit 3 side. 14. Then, the duplexer 15 receives the received radio signal from the antenna 5 and outputs it to the low noise amplifier 11. The low noise amplifier 11 receives the output of the duplexer 15 and outputs it to the filter 13. The filter 13 receives the output of the low noise amplifier 11 and outputs a received high-frequency signal (reference S14 shown in FIG. 2) to the received frequency converter 2. Further, the filter 14 on the transmission frequency conversion unit 3 side receives the transmission high-frequency signal (reference S34 shown in FIG. 3) that is the output of the transmission frequency conversion unit 3 and outputs it to the power amplifier 12. The power amplifier 12 receives the output of the filter 14 and outputs it to the duplexer 15. The duplexer 15 receives the output of the power amplifier 12 and outputs a transmission radio signal to the antenna 5 so that transmission is performed.

  Next, the reception frequency converter 2 will be described. The reception frequency converter 2 includes a first reception frequency mixer 21, a filter 22 that inputs this output, a second reception frequency mixer 23, and a filter 24 that inputs this output. The first frequency mixer 21 receives the received high-frequency signal (reference S14 in FIG. 2) that is the output of the high-frequency processing unit 1 and the fixed-frequency local oscillation signal (the output of the fixed-frequency oscillator 41 of the local oscillation unit 4). 2 are input and mixed, and output to the filter 22. The filter 22 inputs the output of the first reception frequency mixer 21 and outputs it to the second reception frequency mixer 23. The second reception frequency mixer 23 receives the output of the filter 22 (reference S22 in FIG. 2) and the variable frequency reception local oscillation signal (reference S55 in FIG. 2) that is the output of the VCO 53 of the local oscillation unit 4. Are mixed and output to the filter 24 (reference S23 in FIG. 2). The filter 24 receives the output of the second reception frequency mixer 23, and outputs a reception IF signal (reference S24 in FIG. 2) that is the output of the reception frequency converter 2.

  Next, the transmission frequency conversion unit 3 will be described. The transmission frequency conversion unit 3 includes a first transmission frequency mixer 33, a filter 32 that inputs this output, and a second transmission frequency mixer 31. Then, the first transmission frequency mixer 33 generates the transmission IF signal (reference S31 in FIG. 3) and the variable frequency transmission local oscillation signal (reference S65 in FIG. 3) that is the output of the VCO 63 of the local oscillation unit 4. Input, mix, and output to the filter 32 (reference S32 in FIG. 3). The filter 32 receives the output of the first transmission frequency mixer 33 and outputs it to the second transmission frequency mixer 31 (reference S33 in FIG. 3). The second transmission frequency mixer 31 includes an output of the filter 32 (reference S33 in FIG. 3), a fixed frequency local oscillation signal (reference S41 in FIG. 3) that is an output of the fixed frequency oscillator 41 of the local oscillator 4, and Are input and mixed, and the output high-frequency signal (reference S34 in FIG. 3) is output to the high-frequency processing unit 1.

[Operation]
Next, the operation of the radio transmission / reception apparatus configured as described above will be described with reference to FIGS. In particular, the operation on the receiver side will be described with reference to FIG. 2, and the operation on the transmitter side will be described with reference to FIG.

  First, in FIG. 2, the received radio signal received by the antenna 5 and the transmission radio signal transmitted from the antenna 5 are superimposed on the input / output signal of the antenna 5. The received radio signal S11 is input to the duplexer 15 of the high frequency processing unit 1, and is guided to the low noise amplifier 11 (S12). Thereafter, the signal is amplified by the low noise amplifier 11 (S13), unnecessary frequency components are removed by the filter 13, and output to the reception frequency converter 2 as a reception high-frequency signal S14.

  The reception high frequency signal S14 input to the reception frequency converter 2 is first input to the first reception frequency mixer 21. Here, the signal is mixed with the fixed frequency local oscillation signal S41 output from the fixed frequency oscillator 41 of the local oscillation unit 4 to become an output S21 and input to the filter 22. At this time, an unnecessary wave is included in the output S21, and after being removed by the filter 22, it is output to the second reception frequency mixer 23 as the first reception intermediate frequency signal S22.

  Then, in the second reception frequency mixer 23, the first reception intermediate frequency signal S22 and the reception variable frequency local oscillation signal S55 output from the VCO 53 of the local oscillation unit 4 are mixed to become an output S23. 24. At this time, the output S23 includes unnecessary waves, which are removed by the filter 24 and then output as the second reception intermediate frequency signal S24. Thereafter, the second reception intermediate frequency signal S24 is output from the reception frequency conversion unit 2 as a reception IF signal.

  Next, the operation on the transmitter side, that is, at the time of transmission will be described with reference to FIG. The transmission IF signal input to the transmission frequency converter 3 is first input to the first transmission frequency mixer 33 as the first transmission intermediate frequency signal S31. In the first transmission frequency mixer 33, the first transmission intermediate frequency signal S31 and the transmission variable frequency local oscillation signal S65 output from the VCO 63 of the local oscillation unit 4 are mixed to obtain an output S32. Input to the filter 32. At this time, the output S32 includes unnecessary waves, which are removed by the filter 32 and then output to the second transmission frequency mixer 31 as the second transmission intermediate frequency signal S33. In the second transmission frequency mixer 31, the second transmission intermediate frequency signal S33 and the fixed frequency local oscillation signal S41 output from the fixed frequency oscillator 41 of the local oscillation unit 4 are mixed and transmitted. The high frequency signal S34 is output to the high frequency processing unit 1.

  Thereafter, the transmission high-frequency signal S34 input to the high-frequency processing unit 1 is input to the filter 14, where unnecessary waves are removed (S15). Next, after being amplified by the power amplifier 12 (S16), it is guided to the antenna 5 by the duplexer 15 (S17) and transmitted as a transmission radio signal.

  Here, the operation of the local oscillation unit 4 that outputs the local oscillation signal to the reception frequency conversion unit 2 and the transmission frequency conversion unit 3 described above will be described in more detail. In the local oscillator 4, the fixed frequency local oscillation signal S 41 generated by the fixed frequency oscillator 41 is used for the first reception frequency mixer 21 of the reception frequency converter 2 and the second transmission frequency mixer 31 of the transmission frequency converter 3. And also input to the second oscillation circuits 42 and 43 in the local oscillation unit 4. That is, the signal is input to the frequency mixers 51 and 61 provided in the second oscillation circuits 42 and 43.

  In the second oscillation circuit 42 on the receiver side, first, the reference signal S51 generated by the reference signal oscillator 50 is input to the reference signal frequency divider 57 on the reception side. Then, the reference signal frequency divider 57 divides the reference signal S51 up to the phase comparison frequency of the reception system and inputs it to the frequency phase comparator 56 as a reception phase comparison reference signal (S52). The reception variable frequency local oscillation signal S55, which is the output of the VCO 53 on the reception side, is input to the reception frequency converter 2 (S55) and also input to the frequency mixer 51 (S55). At this time, the output (S56) of the frequency mixer 51 includes the sum frequency component and the difference frequency component of the fixed frequency local oscillation signal S41 and the reception variable frequency local oscillation signal S55 as described above. These are input to the filter 52, and a required component is selected and input to the VCO output signal frequency divider 55 (S57). Thereafter, the VCO output signal frequency divider 55 divides the frequency up to the phase comparison frequency of the receiving system, and the output (S58) is input to the frequency phase comparator 56. The frequency phase comparator 56 performs frequency phase comparison with the reception phase comparison reference signal (S52) described above, and generates an error signal (S53). The error signal (S53) is input to the VCO 53 as a frequency control signal (S54) after being given loop characteristics by the loop amplifier 54.

  Similarly, in the second oscillation circuit 43 on the transmitter side, first, the reference signal S51 generated by the reference signal oscillator 50 is input to the reference signal frequency divider 67 on the transmission side. Then, the reference signal frequency divider 67 on the transmission side divides the reference signal S51 to the phase comparison frequency of the transmission system and inputs it to the frequency phase comparator 66 as a transmission phase comparison reference signal (S62). The transmission variable frequency local oscillation signal S65, which is the output of the VCO 63, is input to the transmission frequency converter 3 (S65) and also to the frequency mixer 61 (S65). The output (S66) of the frequency mixer 61 includes the sum frequency component and the difference frequency component of the fixed frequency local oscillation signal S41 and the transmission variable frequency local oscillation signal S65. These are input to the filter 62 (S66), and required components are selected and input to the VCO output signal frequency divider 65 (S67). Thereafter, the VCO output signal divider 65 divides the frequency up to the phase comparison frequency of the transmission system, and the output S68 is input to the frequency phase comparator 66. The frequency phase comparator 66 performs frequency phase comparison with the transmission phase comparison reference signal S62 described above to generate an error signal S63. The error signal S63 is given a loop characteristic by the loop amplifier 64 and then input to the VCO 63 as a frequency control signal S64.

  Next, the frequency and phase relationship in the signal processing described above will be described. First, consider the reception frequency conversion system.

The phase of the fixed frequency local oscillation signal S41 output from the fixed frequency oscillator 41 is φ _F , the phase of the reception variable frequency local oscillation signal S55 output from the VCO 53 of the second oscillation circuit 42 is φ _RXV , and a reference signal generation a reference signal S51 of the phase which is the output from the vessel 50 and phi _R, PLL is the second oscillation circuit 42 is assumed that there is a phase-locked state. At this time, assuming that the filter 52 has selected the sum frequency component, the frequency division number of the VCO output signal frequency divider 55 is V _R , and the frequency division number of the reference signal frequency divider 57 is R _R , these are: ,
φ _F + φ _RXV = (V _R / R _R ) · φ _R + C (1)
Are in a relationship. C is a constant.

Here, assuming that the phase shift Δφ _F is added to the phase φ _F of the fixed frequency local oscillation signal S41 to become φ _F + Δφ _F (the first parenthesis on the left side of the equation (2)), V _R , R _R , Since φ _R does not change, the PLL maintains the phase synchronization state,
(Φ _F + _{Δφ F} ) + (φ _{RXV −Δφ F} ) = (V _R / R _R ) · φ _R + C (2)
Then, the VCO 53 is controlled to move the phase φ _RXV of the reception variable frequency local oscillation signal S55 by _{−Δφ F} (the second parenthesis on the left side of the equation (2)). That is, the sum of the phase of the fixed frequency local oscillation signal S41 and the phase of the reception variable frequency local oscillation signal S55 is controlled so as to be always synchronized with the phase of the reference signal S51.

Since the frequency is a time derivative of the phase, if the frequency of the fixed frequency local oscillation signal S41 is f _F , the frequency of the reception variable frequency local oscillation signal S55 is f _RXV , and the frequency of the reference signal S51 is f _R , The following formula is obtained by differentiating both sides of the formula (1).
f _F + f _RXV = (V _R / R _R ) · f _R (constant) (3)

Here, assuming that a frequency deviation Δf _F is added to the frequency f _F of the fixed frequency local oscillation signal S41 to become f _F + Δf _F (first parenthesis on the left side of the equation (4)), V _R , R _R , Since f _R does not change, the PLL maintains the frequency relationship.
(F _F + Δf _F ) + (f _{RXV −Δf F} ) = (V _R / R _R ) · f _R (4)
Then, the VCO 53 is controlled to move the frequency f _RXV of the reception variable frequency local oscillation signal S55 by _{−Δf F} (the second parenthesis on the left side of the equation (4)). That is, the sum of the frequency of the fixed frequency local oscillation signal S41 and the frequency of the reception variable frequency local oscillation signal S55 is controlled to be always constant.

In this way, the PLL that is the second oscillation circuit 42 performs an operation equivalent to performing phase synchronization control on the output of the VCO _having the output frequency f _F + f _RXV with respect to the reference signal.

Next, consider the movement of the frequency and phase of the reception frequency converter 2 in the state described above. First, the phase and frequency of the reception high-frequency signal S14 that is an input signal to the reception frequency conversion unit 2 are set to φ _RXRF and f _RXRF , respectively, and the phase and frequency of the reception intermediate frequency signal S24 that is an output signal from the reception frequency conversion unit 2 are set to The reception frequency conversion unit 2 is configured so that φ _RXIF and f _{RXIF are established} , and the relationship of the following equation is established between them.
φ _RXIF = φ _RXRF −φ _F −φ _RXV + C ′ = φ _RXRF − (φ _F + φ _RXV ) + C ′
f _RXIF = f _RXRF- f _F- f _RXV = f _RXRF- (f _F + f _RXV )
C ′ is a constant.

At this time, the phase difference φ _RXRF −φ _RXIF and the frequency difference f _RXRF −f _RXIF between the received high frequency signal S14 and the received intermediate frequency signal S24 are:
φ _RXRF −φ _RXIF = φ _F + φ _RXV −C ′ (5)
f _RXRF −f _RXIF = f _F + f _RXV (constant) (6)
Thus, it can be seen from the equations (1) and (3) that it depends only on the reference signal S51 and is stable.

  That is, even if the phase and frequency of the fixed frequency local oscillation signal S41 are shifted, the influence on the reception frequency conversion function is canceled by the phase and frequency movement of the reception variable frequency local oscillation signal S55 controlled by the PLL. Thus, neither the conversion phase nor the conversion frequency as the reception frequency conversion unit is affected by the change. In other words, the second oscillation circuit 42 outputs the reception variable frequency local oscillation signal S55 that increases or decreases opposite to the increase or decrease of the frequency or phase of the fixed frequency local oscillation signal S41. The change in S41 can be corrected (compensated).

  From the above, with the above configuration, the reception frequency conversion function having the same frequency stability as that of the circuit in the conventional example shown in FIG. 16 can be realized by a single PLL circuit, and the fixed frequency local oscillation signal can be obtained. Since it is used, low phase noise characteristics can also be realized.

Further, when selecting the difference frequency component in the filter 52,
φ _F −φ _RXV = (V _R / R _R ) · φ _R + C (7)
f _F −f _RXV = (V _R / R _R ) · f _R (constant) (8)
It becomes. C is a constant.

Here, assuming that the phase shift Δφ _F is added to the phase φ _F of the fixed frequency local oscillation signal S41 to become φ _F + Δφ _F (the first parenthesis on the left side of the expression (7) ′), V _R , R _R Since φ _R does not change, the PLL maintains the phase synchronization state,
(Φ _F + _{Δφ F} ) − (φ _RXV + _{Δφ F} ) = (V _R / R _R ) · φ _R + C (7) ′
Then, the VCO 53 is controlled to move the phase φ _RXV of the reception variable frequency local oscillation signal S55 by + Δφ _F (the second parenthesis on the left side of the expression (7) ′). That is, the difference between the phase of the fixed frequency local oscillation signal S41 and the phase of the reception variable frequency local oscillation signal S55 is controlled so as to be always synchronized with the phase of the reference signal S51.

Further, assuming that a frequency shift Δf _F is added to the frequency f _F of the fixed frequency local oscillation signal S41 to become f _F + Δf _F (the first parenthesis on the left side of the expression (8) ′), V _R , R _R , Since f _R does not change, the PLL maintains the frequency relationship.
(F _F + Δf _F ) − (f _RXV + Δf _F ) = (V _R / R _R ) · f _R (8) ′
Then, the VCO 53 is controlled to move the frequency f _RXV of the reception variable frequency local oscillation signal S55 by + Δf _F (the second parenthesis on the left side of the expression (8) ′). That is, the difference between the frequency of the fixed frequency local oscillation signal S41 and the frequency of the reception variable frequency local oscillation signal S55 is controlled to be always constant.

And
φ _RXIF = φ _RXRF −φ _F + φ _RXV + C ′ = φ _RXRF − (φ _F −φ _RXV ) + C ′
f _RXIF = f _RXRF- f _F + f _RXV = f _RXRF- (f _F- f _RXV )
If the reception frequency conversion unit 2 is configured so that
φ _RXRF −φ _RXIF = φ _F −φ _RXV −C ′ (9)
f _RXRF −f _RXIF = f _F −f _RXV (constant) (10)
Thus, the same effect as described above can be obtained. C ′ is a constant.

Next, the transmission frequency conversion system will be described. As described above, the phase of the fixed frequency local oscillation signal S41 that is output from the fixed frequency oscillator 41 is φ _F , and the phase of the transmission variable frequency local oscillation signal S65 that is output from the VCO 63 of the second oscillation circuit 43 is φ _TXV. , the phase of the reference signal S51 is output from the reference signal generator 50 and phi _R, PLL is the second oscillation circuit 43 is assumed that there is a phase-locked state. At this time, assuming that the filter 62 selects the sum frequency component, the frequency division number of the VCO output signal frequency divider 65 is V _T , and the frequency division number of the reference signal frequency divider 67 is R _T , ,
φ _F + φ _TXV = (V _T / R _T ) · φ _R + C (11)
Are in a relationship. Here, C is a constant.

As for the frequency, the following equation is obtained by differentiating both sides of the equation (11).
f _F + f _TXV = (V _T / R _T ) · f _R (constant) (12)
That is, similar to the reception frequency conversion system described above, the sum of the phases of the fixed frequency local oscillation signal S41 and the transmission variable frequency local oscillation signal S65 is controlled to be stable depending only on the phase of the reference signal S51, and the sum of the frequencies is controlled. Is controlled to be always constant.

Next, let us consider the movement of the phase and frequency of the transmission frequency converter 3 in the state described above. The phase and frequency of the transmission high-frequency signal S34 that is the output signal of the transmission frequency converter 3 are φ _TXRF and f _TXRF , respectively, and the phase and frequency of the transmission intermediate frequency signal S31 that is the input signal are φ _TXIF and f _TXIF , respectively. The transmission frequency conversion unit 3 is configured so that the relationship of C ′ is a constant.
_{φ TXRF = φ TXIF + φ F} + φ TXV + C '= φ TXIF + (φ F + φ TXV) + C'
f _TXRF = f _TXIF + f _F + f _TXV = f _TXIF + (f _F + f _TXV )
At this time, the phase difference φ _TXRF −φ _TXIF and the frequency difference f _TXRF −f _TXIF between the transmission high frequency signal S34 and the transmission intermediate frequency signal S31 are:
φ _TXRF −φ _TXV = φ _F + φ _TXV + C ′ (13)
f _TXRF −f _TXV = f _F + f _TXV (constant) (14)
Thus, it can be seen from the equations (11) and (12) that the signal depends only on the reference signal S51 and is stable.

  As described above, even if the phase and frequency of the fixed-frequency local oscillation signal S41 are shifted, the transmission frequency conversion function is affected by the transmission variable frequency local oscillation signal controlled by the PLL. Canceled by the movement of the phase and frequency in S65, neither the conversion phase nor the conversion frequency as the transmission frequency conversion unit is affected. Therefore, with the above configuration, a transmission frequency conversion function having the same frequency stability as the conventional example shown in FIG.

Further, when selecting the difference frequency component by the filter 62,
φ _F −φ _TXV = (V _T / R _T ) · φ _R + C (15)
f _F −f _TXV = (V _T / R _T ) · f _R (constant) (16)
It becomes. C is a constant. At this time,
_{φ TXRF = φ TXIF + φ F} -φ TXV + C '= φ TXIF + (φ F -φ TXV) + C'
f _TXRF = f _TXIF + f _F- f _TXV = f _TXIF + (f _F- f _TXV )
If the transmission frequency conversion unit 3 is configured so that
φ _TXRF −φ _TXIF = φ _F −φ _TXV + C ′ (constant) (17)
f _TXRF −f _TXIF = f _F −f _TXV (constant) (18)
Thus, the same effect as described above can be obtained. C ′ is a constant.

  In particular, in this embodiment, the fixed frequency local oscillation signal S41 and the reception variable frequency local oscillation signal S55 or the transmission variable frequency local oscillation signal S65 are set to satisfy the following conditions.

  First, as a condition regarding the phase noise characteristics, the phase noise level of the fixed frequency local oscillation signal S41 at the detuning frequency that affects the transmission characteristics of the wireless transmission / reception apparatus is determined by the reception variable frequency local oscillation signal S55 or the transmission variable frequency local oscillation signal S65. It is set lower than the phase noise level at the same detuning frequency.

  Next, as a condition regarding the frequency, the frequency of the fixed frequency local oscillation signal S41 is x times the frequency of the reception variable frequency local oscillation signal S55 or the transmission variable frequency local oscillation signal S65 (shown in the following equation 3), that is, about 2 It is set to 5 times or more. This condition will be further described in detail.

  As in the above equations (8) and (16), the fixed frequency local oscillation signal S41 (frequency Ffix) and the reception variable frequency local oscillation signal S55 or the transmission variable frequency local oscillation signal S65 (VCO output: frequency Fvco (Hz)) Consider the case where the difference frequency (frequency Feq (Hz)) is used.

Feq = Ffix-Fvco (A1)
And the phase noise power (Nfix (W / Hz)) of the free-running oscillator output is equal to the phase noise power (Nvco (W / Hz)) of the VCO output at a certain detuning frequency (the limit value of the condition regarding the phase noise characteristics). Then,
Nfix = Nvco (A2)
The phase noise power (Ntotal (W / Hz)) added to the reception signal in the entire reception frequency converter 2 is the sum of these powers, which is twice the value at each oscillator output, that is, about 3 dB increase.

Ntotal = Nfix + Nvco = 2 ・ Nfix = 2 ・ Nvco (A3)
On the other hand, an equivalent local oscillation frequency can also be obtained by using only a VCO and multiplying its output. If the multiplication factor is α,
α ・ Fvco = Feq (A4)
At this time, the phase noise level is multiplied by (square of α) (Nvco · α ² ).

And since the phase noise characteristic in this invention is calculated | required that it is better than the thing by VCO multiplication, from said (A3) Formula,
Nvco · α ² > Ntotal = 2 · Nvco (A5)
It becomes. Therefore,

Here, using the above equations (A1) and (A4), if α and Fvco are deleted and arranged,

It becomes.

  From the above, the frequency of the free-running oscillator output needs to be set to x times (shown in Equation 4) or more, that is, about 2.5 times or more of the VCO output frequency.

  In this way, in this embodiment, since the free-running oscillator is used as the fixed frequency local oscillator instead of the VCO, the phase noise characteristics can be improved. Also, the fixed frequency local oscillation signal is frequency-mixed with the reception variable frequency local oscillation signal or the transmission variable frequency local oscillation signal, and their sum frequency or difference frequency signal is input to the PLL and phase-synchronized. Even if a free-running oscillator is used as the oscillator, it is possible to obtain the same frequency stability as when a phase synchronization is performed by a PLL using a VCO as a fixed frequency local oscillator. Therefore, by improving the phase noise characteristics of the above-described wireless transmission / reception apparatus, the signal error rate is improved, the signal transmission throughput is improved, the service is improved by reducing transmission delay, and the power consumption required for information retransmission processing is reduced. Can do.

  Furthermore, the fixed frequency local oscillation signal is frequency-mixed with the reception variable frequency local oscillation signal or the transmission variable frequency local oscillation signal, and the sum frequency or difference frequency signal thereof is input to the PLL and phase-synchronized, so that the PLL circuit The number can be reduced. As a result, the shape can be reduced, power consumption can be reduced, and the manufacturing cost can be further reduced. Accordingly, by using the wireless transceiver of the present invention for a mobile phone terminal, further miniaturization of the terminal can be realized, and portability can be improved. At the same time, the battery duration, that is, standby time and call time can be further extended.

  Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 4 is a circuit diagram showing the configuration of the present invention, and FIGS. 5 to 6 are explanatory diagrams showing the operation of the circuit.

  The transmitter / receiver shown below is not configured to perform the frequency conversion twice (double superheterodyne method), but a modulator and a frequency in the transmission system as in the second conventional example described with reference to FIG. A modulation / demodulation unit having a single conversion type frequency conversion function using one converter and one frequency converter and one demodulator in the reception system is provided.

[Constitution]
As shown in FIG. 4, the radio transceiver according to the present embodiment includes an antenna 105, a high frequency processing unit 101 connected to the antenna 105, a demodulation unit 102 that processes a reception signal, and a modulation unit that processes a transmission signal. 103 and a local oscillation unit 104 (local oscillation device) that generates a local oscillation signal. Hereinafter, each configuration will be described in detail.

  First, the local oscillating unit 104 has substantially the same configuration as that of the first embodiment described above. Specifically, it has a fixed frequency oscillator 141 (first oscillating means) that outputs a first local oscillation signal that is a fixed frequency signal. The fixed frequency oscillator 141 is a free-running oscillator, for example, a dielectric oscillator. Then, the first local oscillation signal (reference S141 in FIG. 5) which is an output from the fixed frequency oscillator 141 is input to a frequency mixer 121 of the demodulator 102 described later, and also into the second oscillation circuit 142. It is input to the provided frequency mixer 151.

  The fixed frequency oscillator 141 is also shared on the transmitter side, that is, the modulation unit 103 side, and a first local oscillation signal (reference numeral S141 in FIG. 6) that is an output from the fixed frequency oscillator 141 is a modulation unit 103 described later. Is input to the frequency mixer 131 as a first local oscillation signal. Further, the fixed frequency oscillator 141 is also input to the frequency mixer 161 provided in the second oscillation circuit 143 on the modulation unit side.

  The local oscillation unit 104 includes a second oscillation circuit 142 (see FIG. 5) on the demodulation unit side that outputs a variable frequency demodulation carrier signal (second local oscillation signal) to the demodulation unit 102, and a modulation. A modulation unit side second oscillation circuit 143 (see FIG. 6) that outputs a variable frequency modulation carrier wave signal (second local oscillation signal) to the unit 103. The configuration of the circuits 142 and 143 will be described first by taking the demodulator 102 side as an example.

  The second oscillation circuit 142 shown in FIG. 5 is a negative feedback circuit, and constitutes a PLL circuit having a reference signal generator 150 and a VCO 153 that outputs a carrier signal for variable frequency demodulation. Specifically, the reference signal generator 150, a reference signal divider 157 to which the output of the reference signal generator 150 is input, a VCO output signal divider 155 that divides the output from the VCO 153, The frequency phase comparator 156 that compares the frequency-divided output with the frequency-divided output from the reference signal frequency divider 157, and the loop amplifier that inputs the error signal from the frequency-phase comparator 156 and outputs the frequency control signal to the VCO 153 154. Further, the present embodiment includes a frequency mixer 151 that mixes the output of the VCO 153 and the output from the fixed frequency oscillator 141, and a filter 152 that filters the mixed output, and the output from the filter 152 is The VCO output signal divider 155 is input. The output from the VCO 153 is input as a variable frequency demodulation carrier signal (reference S155 in FIG. 5) to the demodulator 123 of the demodulator 102 described later.

  Also, the second oscillation circuit 143 (see FIG. 6) on the modulation unit side provided in the local oscillator 104 has a configuration substantially similar to that of the second oscillation circuit 142 on the demodulation unit side. That is, a PLL circuit having a VCO 163 that outputs a carrier signal for variable frequency modulation is configured, and a frequency mixer 161 that mixes an output from the VCO 163 and a fixed local oscillation signal output from the fixed frequency oscillator 141; A filter 162 that filters the mixed output, a VCO output signal divider 165 that divides the output from the filter 162, a reference signal divider 167 that receives the output of the reference signal generator 150, A frequency phase comparator 166 that compares the divided output with the divided output from the VCO output signal divider 165, and a loop amplifier that inputs an error signal from the frequency phase comparator 166 and outputs a frequency control signal to the VCO 163. 164. Then, the output from the VCO 163 is input to the modulator 133 of the modulation unit 103 described later as a variable frequency modulation carrier signal (reference S165 in FIG. 6).

  Next, the high frequency processing unit 101 will be described. The high-frequency processing unit 101 includes a duplexer 115 connected to the antenna 105, a low noise amplifier 111 and a filter 113 connected to the demodulation unit 102 side, and a power amplifier 112 and a filter 114 connected to the modulation unit 103 side. I have. The high-frequency processing unit 101 receives a reception radio signal from the antenna 105, outputs the reception high-frequency signal to the demodulation unit 102, and inputs a transmission high-frequency signal that is an output of the modulation unit 103, thereby transmitting a transmission radio signal. Is output to the antenna 105. The configuration is almost the same as that of the first embodiment.

  Next, the demodulator 102 will be described. The demodulator 102 includes a reception frequency mixer 121, a filter 122 that inputs this output, a demodulator 123, and a filter 124 that inputs this output. Then, the reception frequency mixer 121 receives the received high-frequency signal (reference numeral S114 in FIG. 5) that is the output of the high-frequency processing unit 101 and the fixed-frequency local oscillation signal that is the output of the fixed-frequency oscillator 141 of the local oscillation unit 104 (FIG. 5). Are input and mixed, and output to the filter 122. The filter 122 receives the output of the reception frequency mixer 121 and outputs it to the demodulator 123. The demodulator 123 receives the output of the filter 122 (reference S122 in FIG. 5) and the variable frequency demodulation carrier signal (reference S155 in FIG. 5) that is the output of the VCO 153 of the local oscillator 104, and performs demodulation processing. Is output to the filter 124 (reference S123 in FIG. 5). The filter 124 receives the output of the demodulator 123, and outputs a received BB signal (reference S124 in FIG. 5) that is the output of the demodulator 102.

  Next, the modulation unit 103 will be described. The modulation unit 103 includes a modulator 133, a filter 132 that inputs this output, and a transmission frequency mixer 131. The modulator 133 receives the transmission BB signal (reference S131 in FIG. 6) and the variable frequency modulation carrier signal (reference S165 in FIG. 6) that is the output of the VCO 163 of the local oscillation unit 104, and performs modulation processing. And output to the filter 132 (reference S132 in FIG. 6). The filter 132 receives the output of the modulator 133 and outputs it to the transmission frequency mixer 131 (reference S133 in FIG. 6). The transmission frequency mixer 131 receives the output of the filter 132 (reference S133 in FIG. 6) and the fixed frequency local oscillation signal (reference S141 in FIG. 6) that is the output of the fixed frequency oscillator 141 of the local oscillation unit 104. Then, a transmission high-frequency signal (reference S134 in FIG. 6) as an output is output to the high-frequency processing unit 101.

[Operation]
Next, the operation of the radio transmission / reception apparatus configured as described above will be described with reference to FIGS. In particular, the operation on the receiver side, that is, the demodulation unit 102 side will be described with reference to FIG. 5, and the operation on the transmitter side, that is, the modulation unit 103 side will be described with reference to FIG.

  First, in FIG. 5, a reception radio signal received by the antenna 105 and a transmission radio signal transmitted from the antenna 105 are superimposed on the input / output signal of the antenna 105. The received radio signal S111 is input to the duplexer 115 of the high frequency processing unit 101, and is guided to the low noise amplifier 111 (S112). Thereafter, the signal is amplified by the low noise amplifier 111 (S113), unnecessary frequency components are removed by the filter 113, and output to the demodulator 102 as a received high frequency signal S114.

  The reception high-frequency signal S114 input to the demodulation unit 102 is first input to the reception frequency mixer 121. Here, the signal is mixed with the fixed frequency local oscillation signal S141 output from the fixed frequency oscillator 141 of the local oscillation unit 104, frequency-converted, becomes an output S121, and is input to the filter 122. At this time, the output S121 includes an unnecessary wave, which is removed by the filter 122 and then output to the demodulator 123 as a reception intermediate frequency signal S122.

  The demodulator 123 mixes the reception intermediate frequency signal S122 and the variable frequency demodulation carrier signal S155 output from the VCO 153 of the local oscillation unit 104 to produce an output S123. The variable frequency demodulation carrier signal S155 is set so that the reception intermediate frequency signal S122 and the variable frequency demodulation carrier signal S155 have the same frequency. Thereafter, the output S123 is input to the filter 124. The output S123 includes unnecessary waves, and the filter 124 removes them and outputs them as a reception baseband signal S124. Thereafter, reception baseband signal S124 is output from demodulation section 202 as a reception BB signal.

  Next, the transmitter side (modulation unit 103 side), that is, the operation during transmission will be described with reference to FIG. The transmission BB signal input to modulation section 103 is first input to modulator 133 as transmission baseband signal S131. In this modulator 133, the variable frequency modulation carrier signal S 165 output from the VCO 163 of the local oscillator 104 is modulated by the transmission baseband signal S 131, becomes an output S 132, and is input to the filter 132. At this time, an unnecessary wave is included in the output S132, and after being removed by the filter 132, it is output to the transmission frequency mixer 131 as a transmission intermediate frequency signal S133. Note that the frequencies of the variable frequency modulation carrier signal S165 and the transmission intermediate frequency signal S133 are the same. In the transmission frequency mixer 131, the transmission intermediate frequency signal S 133 and the fixed frequency local oscillation signal S 141 output from the fixed frequency oscillator 141 of the local oscillation unit 104 are mixed and subjected to frequency conversion processing, and the transmission high frequency signal S 134. And output to the high-frequency processing unit 101.

  Thereafter, the transmission high-frequency signal S134 input to the high-frequency processing unit 101 is output to the antenna 105 as a transmission radio signal after unnecessary wave removal and amplification. The detailed description of the operation is the same as that of the high-frequency processing unit 101 of the first embodiment, and will be omitted.

  Next, the operation of the local oscillator 104 that outputs local oscillation signals (including modulation / demodulation carrier signals) to the demodulator 2 and the modulator 3 will be described in detail. First, in the local oscillation unit 104, the fixed frequency local oscillation signal S141 generated by the fixed frequency oscillator 141 is input to the reception frequency mixer 121 of the demodulation unit 102 and the transmission frequency mixer 131 of the modulation unit 103, and the local oscillation is performed. Also input to the second oscillation circuits 142 and 143 in the unit 104. That is, the signal is input to the frequency mixers 151 and 161 provided in the second oscillation circuits 142 and 143.

  In the second oscillation circuit 142 on the receiver side, first, the reference signal S151 generated by the reference signal oscillator 150 is input to the reference signal frequency divider 157 on the reception side. Then, the reference signal frequency divider 157 divides the reference signal S151 to the phase comparison frequency of the reception system, and inputs it to the frequency phase comparator 156 as a reception phase comparison reference signal (S152). The variable frequency demodulation carrier signal S155, which is the output of the VCO 153 on the receiving side, is input to the demodulator 102 (S155) and also input to the frequency mixer 151 (S155). At this time, the output (S156) of the frequency mixer 151 includes the sum frequency component and the difference frequency component of the fixed frequency local oscillation signal S141 and the variable frequency demodulation carrier signal S155 as described above. These are input to the filter 152, and necessary components are selected and input to the VCO output signal frequency divider 155 (S157). Thereafter, the VCO output signal frequency divider 155 divides the frequency up to the phase comparison frequency of the receiving system, and the output (S158) is input to the frequency phase comparator 156. The frequency phase comparator 156 performs frequency phase comparison with the reception phase comparison reference signal (S152) described above to generate an error signal (S153). The error signal (S153) is given a loop characteristic by the loop amplifier 154 and then input to the VCO 153 as a frequency control signal (S154).

  Similarly, in the second oscillation circuit 143 on the transmitter side, the reference signal frequency divider 167 divides the reference signal S151 up to the phase comparison frequency of the transmission system, and sends it to the frequency phase comparator 166 as a transmission phase comparison reference signal. Input (S162). The variable frequency modulation carrier signal S165, which is the output of the VCO 163, is input to the modulator 103 (S165) and also input to the frequency mixer 161 (S165). The output (S166) of the frequency mixer 161 includes a sum frequency component and a difference frequency component of the fixed frequency local oscillation signal S141 and the variable frequency modulation carrier signal S165. These are input to the filter 162 (S166), and required components are selected and input to the VCO output signal frequency divider 165 (S167). Thereafter, the VCO output signal frequency divider 165 divides the frequency up to the phase comparison frequency of the transmission system, and the output S168 is input to the frequency phase comparator 166. The frequency phase comparator 166 performs frequency phase comparison with the transmission phase comparison reference signal S162 described above to generate an error signal S163. The error signal S163 is given a loop characteristic by the loop amplifier 164 and then input to the VCO 163 as a frequency control signal S164.

  Next, the frequency and phase relationship in the signal processing described above will be described. First, consider the demodulation system.

The phase of the fixed frequency local oscillation signal S141 output from the fixed frequency oscillator 141 is φ _F , the frequency of the variable frequency demodulation carrier signal S155 output from the VCO 153 of the second oscillation circuit 142 is φ _RXV , and a reference signal generation _Let us consider a case where the phase of the reference signal S151, which is an output from the device 150, is φR, and the PLL that is the second oscillation circuit 142 is in a phase-synchronized state. At this time, assuming that the filter 152 selects the sum frequency component, the frequency division number of the VCO output signal frequency divider 155 is V _R , and the frequency division number of the reference signal frequency divider 157 is R _R , ,
φ _F + φ _RXV = (V _R / R _R ) · φ _R + C (19)
Are in a relationship. C is a constant.

Here, assuming that the phase shift Δφ _F is added to the phase φ _F of the fixed frequency local oscillation signal S 141 to become φ _F + Δφ _F (the first parenthesis on the left side of the equation (20)), V _R , R _R , Since φ _R does not change, the PLL maintains the phase synchronization state,
(Φ _F + _{Δφ F} ) + (φ _{RXV −Δφ F} ) = (V _R / R _R ) · φ _R + C (20)
Then, the VCO 153 is controlled to move the phase φ _RXV of the variable frequency demodulation carrier signal S155 by _{−Δφ F} (the second parenthesis on the left side of the equation (20)). That is, the sum of the phase of the fixed frequency local oscillation signal S141 and the phase of the variable frequency demodulation carrier signal S155 is controlled so as to be always synchronized with the phase of the reference signal S151.

Since the frequency is a time derivative of the phase, if the frequency of the fixed frequency local oscillation signal S141 is f _F , the frequency of the variable frequency modulation carrier signal S155 is f _RXV , and the frequency of the reference signal S151 is f _R , The following formula is obtained by differentiating both sides of the formula (19).
f _F + f _RXV = (V _R / R _R ) · f _R (constant) (21)

Here, if a frequency shift Δf _F is added to the frequency f _F of the fixed frequency local oscillation signal S141 to become f _F + Δf _F (the first parenthesis on the left side of the equation (22)), V _R , R _R , Since f _R does not change, the PLL maintains the frequency relationship.
(F _F + Δf _F ) + (f _{RXV −Δf F} ) = (V _R / R _R ) · f _R (22)
Then, the VCO 153 is controlled to move the frequency f _RXV of the variable frequency demodulation carrier signal S155 by _{−Δf F} (the second parenthesis on the left side of the equation (22)). That is, the sum of the frequency of the fixed frequency local oscillation signal S141 and the frequency of the variable frequency demodulation carrier signal S155 is controlled to be always constant.

As described above, the PLL which is the second oscillation circuit 142 performs an operation equivalent to performing phase synchronization control on the output of the VCO _having the output frequency f _F + f _RXV with respect to the reference signal.

Next, consider the frequency and phase movement of the demodulator 102 in the above state. First, the phase and frequency of the received high-frequency signal S114 that is an input signal to the demodulator 102 are φ _RXRF and f _RXRF , respectively, and the phase of the received baseband signal S124 that is an output signal from the demodulator 102 is φ _RXBB . Note that the frequency of the received baseband signal S124 is zero. Then, the demodulator 102 is configured so that the relationship of the following equation is established between them.
φ _RXBB = φ _RXRF −φ _F −φ _RXV + C ′ = φ _RXRF − (φ _F + φ _RXV ) + C ′
f _RXRF −f _F −f _RXV = f _RXRF − (f _F + f _RXV ) = 0
C ′ is a constant.

At this time, the phase difference φ _RXRF −φ _RXBB between the reception high-frequency signal S114 and the reception baseband signal S124 and the frequency of the reception high-frequency signal S114 are:
φ _RXRF −φ _RXBB = φ _F + φ _RXV −C ′ (23)
f _RXRF = f _F + f _RXV (constant) (24)
From Equations (19) and (21), it can be seen that only the reference signal S151 depends and is stable.

  That is, even if the phase and frequency of the fixed frequency local oscillation signal S141 are shifted, the influence on the demodulation function is offset by the phase and frequency movement of the variable frequency demodulation carrier signal S155 controlled by the PLL. Neither the conversion phase or the conversion frequency as a demodulator is affected by this. In other words, since the second oscillation circuit 142 outputs the variable frequency demodulation carrier signal S155 that increases or decreases opposite to the increase or decrease of the frequency or phase of the fixed frequency local oscillation signal S141, the fixed frequency local oscillation signal is output. The change in S141 can be corrected (compensated).

  As described above, with the above-described configuration, the frequency conversion function and the demodulation function having the same frequency stability as the circuit in the conventional example shown in FIG. Since the signal is used, low phase noise characteristics can also be realized.

Further, when selecting the difference frequency component by the filter 152,
φ _F −φ _RXV = (V _R / R _R ) · φ _R + C (25)
f _F −f _RXV = (V _R / R _R ) · f _R (constant) (26)
It becomes. C is a constant. At this time,
φ _RXBB = φ _RXRF −φ _F + φ _RXV + C ′ = φ _RXRF − (φ _F −φ _RXV ) + C ′
f _RXRF −f _F + f _RXV = f _RXRF − (f _F −f _RXV ) = 0
If the demodulator 102 is configured so that
φ _RXRF −φ _RXBB = φ _F −φ _RXV −C ′ (27)
f _RXRF = f _F −f _RXV (constant) (28)
Thus, the same effect can be obtained. C ′ is a constant.

Next, the modulation system will be described. As described above, the phase of the fixed frequency local oscillation signal S141 output from the fixed frequency oscillator 141 is φ _F , and the phase of the variable frequency modulation carrier signal S165 output from the VCO 163 of the second oscillation circuit 143 is φ _TXV. , the phase of the reference signal S151 which is output from the reference signal generator 150 and phi _R, PLL is the second oscillation circuit 143 consider the case in the phase-locked state. At this time, if the filter 162 selects the sum frequency component, the frequency division number of the VCO output signal divider 165 is V _T , and the frequency division number of the reference signal frequency divider 167 is R _T , ,
φ _F + φ _TXV = (V _T / R _T ) · φ _R + C (29)
Are in a relationship. Here, C is a constant.

As for the frequency, the following equation is obtained by differentiating both sides of the equation (29).
f _F + f _TXV = (V _T / R _T ) · f _R (constant) (30)
That is, as in the demodulation system described above, the sum of the phases of the fixed frequency local oscillation signal S141 and the variable frequency modulation carrier signal S165 is always controlled to be synchronized with the phase of the reference signal S151, and the sum of the frequencies is always constant. It is controlled to become.

Next, the phase and frequency movement of the modulation unit 103 in the above-described state will be considered. Which is an output signal transmitted RF signal S134 the phase of the modulation unit 103, respectively frequency phi _TXRF, f _TXRF, the phase of the transmission baseband signal S131 which is the input signal and phi _TXBB, the relationship following equation between them The modulation unit 103 is configured to hold. C ′ is a constant.
_{φ TXRF = φ TXBB + φ F} + φ TXV + C '= φ TXRF + (φ F + φ TXV) + C'
f _TXRF = f _F + f _TXV (constant) (31)

At this time, the frequency of the transmission high-frequency signal S134 is given by Equation (31) and is constant from Equation (30). The phase difference φ _TXRF −φ _TXBB between the transmission high-frequency signal S134 and the transmission baseband signal S131 is
φ _TXRF −φ _TXBB = φ _F + φ _TXV + C ′ (32)
From equation (29), it can be seen that it depends only on the reference signal S151 and is stable.

  As described above, even if the phase and frequency of the fixed frequency local oscillation signal S141 are shifted as in the demodulation side described above, the influence on the modulation function is the effect of the variable frequency modulation carrier signal S165 controlled by the PLL. It is canceled out by the movement of the phase and frequency, and neither the conversion phase or the conversion frequency as the modulation unit is affected by the movement. Therefore, with the above configuration, a frequency conversion function and a modulation function having the same frequency stability as the conventional example shown in FIG. 18 can be realized by a single PLL circuit.

Further, when selecting the difference frequency component by the filter 162,
φ _F −φ _TXV = (V _T / R _T ) · φ _R + C (33)
f _F −f _TXV = (V _T / R _T ) · f _R (constant) (34)
It becomes. C is a constant. At this time,
φ _TXRF = φ _TXBB + φ _{F −} φ _TXV + C ′ = φ _TXBB + (φ _{F −} φ _TXV ) + C ′
f _TXRF = f _F- f _TXV (35)
If the modulation unit 103 is configured so that the frequency of the transmission high-frequency signal S134 is given by the equation (35), it is constant from the equation (34). The phase difference φ _TXRF −φ _TXBB between the transmission high-frequency signal S134 and the transmission baseband signal S131 is
φ _TXRF −φ _TXBB = φ _F −φ _TXV + C ′ (36)
Thus, the same effect can be obtained from the equation (33). C ′ is a constant.

  In particular, in this embodiment, the fixed frequency local oscillation signal S141 and the variable frequency demodulation carrier signal S155 or the variable frequency modulation carrier signal S165 are set to satisfy the following conditions.

  First, as a condition regarding the phase noise characteristic, the phase noise level of the fixed frequency local oscillation signal S141 at the detuning frequency that affects the transmission characteristic of the wireless transmission / reception apparatus is the variable frequency demodulation carrier signal S155 or the variable frequency modulation carrier signal S165. It is set lower than the phase noise level at the same detuning frequency.

  Next, as a condition regarding the frequency, the frequency of the fixed frequency local oscillation signal S141 is x times the frequency of the variable frequency demodulation carrier signal S155 or the variable frequency modulation carrier signal S165 (shown in the following equation 6), that is, about 2 It is set to 5 times or more. This condition is as described in the above embodiment.

  In this way, in this embodiment, since the free-running oscillator is used as the fixed frequency local oscillator instead of the VCO, the phase noise characteristics can be improved. Also, the fixed frequency local oscillation signal is frequency-mixed with the variable frequency demodulation carrier signal or variable frequency modulation carrier signal, and the sum frequency or difference frequency signal is input to the PLL and phase-synchronized, so that the fixed frequency local oscillation signal is Even if a free-running oscillator is used as the oscillator, it is possible to obtain the same frequency stability as when a phase synchronization is performed by a PLL using a VCO as a fixed frequency local oscillator. Therefore, by improving the phase noise characteristics of the above-described wireless transmission / reception apparatus, the signal error rate is improved, the signal transmission throughput is improved, the service is improved by reducing transmission delay, and the power consumption required for information retransmission processing is reduced. Can do.

  Furthermore, the fixed frequency local oscillation signal is frequency-mixed with the variable frequency demodulation carrier signal or the variable frequency modulation carrier signal, and the sum frequency or difference frequency signal is input to the PLL and phase-synchronized. The number can be reduced. As a result, the shape can be reduced, power consumption can be reduced, and the manufacturing cost can be further reduced. Accordingly, by using the wireless transceiver of the present invention for a mobile phone terminal, further miniaturization of the terminal can be realized, and portability can be improved. At the same time, the battery duration, that is, standby time and call time can be further extended.

  Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 7 is a circuit diagram showing the configuration of the wireless transceiver in the present embodiment.

  As shown in FIG. 7, the basic configuration of the wireless transceiver in the present embodiment is almost the same as that in the first embodiment. In this embodiment, a frequency divider 71 is further provided between the fixed frequency local oscillator 41 and the first reception frequency mixer 21. A frequency divider 72 is also provided between the VCO 53 and the second reception frequency mixer 23. The frequency dividing numbers of these frequency dividers 71 and 72 are equal.

  The configuration on the transmitter side is the same, and a frequency divider 73 is installed between the fixed frequency local oscillator 41 and the second transmission frequency mixer 31, and the VCO 63 and the first transmission frequency mixer 33. A frequency divider 74 is also provided between the two. The frequency dividing numbers of these frequency dividers 73 and 74 are also equal.

  By doing so, the following effects can be obtained. In the first embodiment described above, the output frequency of the frequency mixer 51, which is an intermediate signal in the second oscillation circuit 42, and the frequency of the weak reception radio signal are the reception intermediate frequency signal S24 (see FIG. 2). Only the frequency of was away. For this reason, the output of the frequency mixer 51 may interfere with the received radio signal. However, by introducing the frequency dividers 71 and 72, the frequency can be separated by a multiple of the frequency division number, and the interference problem can be avoided.

  Similarly, in the first embodiment described above, the output frequency of the frequency mixer 61, which is an intermediate signal in the second oscillation circuit 43, and the frequency of the strong transmission radio signal are determined by the transmission intermediate frequency signal S31 ( Only the frequency shown in FIG. For this reason, there is a possibility that the transmission radio signal interferes with the output of the frequency mixer 61. However, by introducing the frequency dividers 73 and 74, the frequency can be separated by a multiple of the frequency division number, and the interference problem can be avoided.

  Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 8 is a circuit diagram showing the configuration of the wireless transceiver in the present embodiment.

  As shown in FIG. 8, the basic configuration of the wireless transceiver in the present embodiment is almost the same as that in the second embodiment described above. In this embodiment, a frequency divider 171 is further provided between the fixed frequency local oscillator 141 and the reception frequency mixer 121. A frequency divider 172 is also provided between the VCO 153 and the demodulator 123. The frequency dividers 171 and 172 have the same frequency division number.

  The configuration on the transmitter side is the same, and a frequency divider 173 is installed between the fixed frequency local oscillator 141 and the transmission frequency mixer 131, and the frequency division is also performed between the VCO 163 and the modulator 133. A container 174 is installed. The frequency dividing numbers of these frequency dividers 173 and 174 are also equal.

  By doing so, the following effects can be obtained. In the second embodiment described above, the output frequency of the frequency mixer 151 that is an intermediate signal in the second oscillation circuit 142 and the frequency of the weak received radio signal are the same. The output may interfere with the received radio signal. However, by introducing the frequency dividers 171 and 172, the frequency can be separated by a multiple of the frequency division number, and the interference problem can be avoided.

  Similarly, in the second embodiment described above, the output frequency of the frequency mixer 161, which is an intermediate signal in the second oscillation circuit 143, and the frequency of the strong transmission radio signal are the same. There is a possibility that the radio signal interferes with the output of the frequency mixer 161. However, by introducing the frequency dividers 173 and 174, the frequency can be separated by a multiple of the frequency division number, and the interference problem can be avoided.

  Next, a fifth embodiment of the present invention will be described with reference to FIGS. In the local oscillators 4 and 104 in the above-described embodiment, the case where two types of local oscillation signals (including the case of a carrier wave signal) are output to the frequency converters 2 and 3 and the modems 102 and 103 has been described. In the present embodiment, a case where the local oscillation unit 204 outputs three or more types of local oscillation signals (carrier wave signals) will be described. 9 and 11 are partial circuit diagrams of the configuration of the transceiver according to the present embodiment, and FIG. 10 is an explanatory diagram illustrating the operation of the circuit.

[Constitution]
Since the transmitter / receiver in the present embodiment has almost the same configuration as that in the above-described first embodiment, in FIG. Only the configuration on the receiver side of the frequency converter 202 and the local oscillator 204 is shown. Further, FIG. 11 shows only the configuration on the transmitter side of the transmitter / receiver in which the configuration on the reception side is omitted, that is, the transmission frequency conversion unit 203 and the local oscillation unit 204.

  As shown in FIG. 9, the local oscillating unit 204 in the present embodiment is different from the first fixed frequency oscillator 241 (first oscillating means) that outputs a first local oscillating signal that is a fixed frequency signal. A second fixed frequency oscillator 242 (another fixed frequency oscillating means) that outputs a second local oscillation signal that is a fixed frequency signal, and these fixed frequency oscillators 241 and 242 are free-running oscillators. . Then, the first local oscillation signal (reference S241 in FIG. 10) that is an output from the first fixed frequency oscillator 241 is input to the first frequency mixer 221 of the reception frequency converter 202 described later, The second local oscillation signal (reference S 242 in FIG. 10), which is an output from the fixed frequency oscillator 242, is input to the second frequency mixer 223 of the reception frequency converter 202.

  Further, the local oscillation unit 204 includes a frequency mixer 243 in a third oscillation circuit 245 described later, and the first and second fixed frequency oscillation signals S241 and S242 are also input to the frequency mixer 243. Is done. Although only the configuration on the receiver side is shown in FIG. 9, as shown in FIG. 11, the first and second fixed frequency oscillation signals S <b> 241 and S <b> 242 are two frequencies of the transmission frequency conversion unit 203 described later. The signals are also input to and shared by the mixers 231 and 233 and the frequency mixer 244 in the third oscillation circuit 246 on the transmission side.

  Furthermore, the local oscillation unit 204 includes a third oscillation circuit 245 that outputs a variable frequency local oscillation signal that is a third local oscillation signal to the reception frequency conversion unit 202. The third oscillation circuit 245 has a configuration similar to that of the second oscillation circuit 42 and the like in the first and second embodiments, and includes a reference signal generator 250 and a VCO 253 that outputs a variable frequency local oscillation signal. The PLL circuit is provided. Specifically, the reference signal generator 250, a reference signal divider 257 to which the output of the reference signal generator 250 is input, a VCO output signal divider 255 that divides the output from the VCO 253, The frequency phase comparator 256 that compares the divided output with the divided output from the reference signal frequency divider 257, and the loop amplifier that inputs the error signal from the frequency phase comparator 256 and outputs the frequency control signal to the VCO 253 254. Further, a frequency mixer 243 that inputs and mixes the outputs of the two fixed frequency oscillators 241 and 242, a filter 258 that filters the mixed output of the frequency mixer 243, an output of the VCO 253, and the two fixed A frequency mixer 251 for mixing the mixed frequency signal (output from the filter 258) of the frequency oscillators 241 and 242 and a filter 252 for filtering the mixed output are provided, and the output from the filter 252 is the above-described output. Input to the VCO output signal divider 255. Then, the output from the VCO 253 is input to a third frequency mixer 225 of the reception frequency converter 202 described later as a reception variable frequency local oscillation signal (reference S255 in FIG. 10) which is a third local oscillation signal. The

  Next, the reception frequency conversion unit 202 will be described. The reception frequency conversion unit 202 in the present embodiment has substantially the same configuration as the reception frequency conversion unit 2 in the first embodiment described above, but is provided with three frequency mixers 221, 223, and 225. Different. However, the operation is almost the same. Specifically, a first reception frequency mixer 221, a filter 222 that inputs this output, a second reception frequency mixer 223, a filter 224 that inputs this output, and a third reception frequency mixer 225 and a filter 226 for inputting the output. The first frequency mixer 221 receives the received high-frequency signal (reference numeral S214 in FIG. 10) that is the output of the high-frequency processing unit and the first fixed frequency oscillator 241 that is the output of the first fixed-frequency oscillator 241 of the local oscillation unit 204. The frequency local oscillation signal (reference S241 in FIG. 10) is input, mixed, and output to the filter 222 (reference S221 in FIG. 10). The second reception frequency mixer 223 outputs the second fixed frequency local oscillation signal (FIG. 10) which is the output of the filter 222 (reference S222 in FIG. 10) and the output of the second fixed frequency oscillator 242 of the local oscillation unit 204. Are input and mixed, and are output to the filter 224 (reference S223 in FIG. 10). The third reception frequency mixer 225 inputs the output of the filter 224 (reference S224 in FIG. 10) and the variable frequency reception local oscillation signal (reference S255 in FIG. 10) that is the output of the VCO 253 of the local oscillation unit 204. Are mixed and output to the filter 226 (reference S225 in FIG. 10). Then, the filter 226 receives the output of the third reception frequency mixer 225, and outputs a reception IF signal (reference S226 in FIG. 10) that is the output of the reception frequency converter 202.

  Further, as shown in FIG. 11, the third oscillation circuit 246 which is the configuration on the transmitter side in the local oscillation unit 204 also has the same configuration as the configuration on the receiver side described above, and the variable frequency local oscillation A PLL circuit having a VCO 263 that outputs a signal is configured. Specifically, a reference signal frequency divider 267 to which the output of the reference signal generator 250 is input, a VCO output signal frequency divider 265 that divides the output from the VCO 263, and the divided output and the reference signal. A frequency phase comparator 266 that compares the frequency-divided output from the frequency divider 267; and a loop amplifier 264 that inputs an error signal from the frequency phase comparator 266 and outputs a frequency control signal to the VCO 263. . Furthermore, a frequency mixer 244 that inputs and mixes the outputs of the two fixed frequency oscillators 241 and 242 described above, a filter 268 that filters the mixed output of the frequency mixer 244, an output of the VCO 263, and the two fixed frequencies. A frequency mixer 261 for mixing the mixed frequency signals (output from the filter 268) of the oscillators 241 and 242 and a filter 262 for filtering the mixed output are provided, and the output from the filter 262 is the VCO. Input to the output signal divider 265. The output from the VCO 263 is input to one frequency mixer 235 in the transmission frequency conversion unit 203 as a transmission variable frequency local oscillation signal that is a third local oscillation signal.

  As shown in FIG. 11, the transmission frequency conversion unit 203 on the transmitter side also has three frequency mixers 231, 233, 235, filters 232, 234, similar to the reception frequency conversion unit 202 described above. It operates in the same way as the receiver side.

[Operation]
Next, the operation of the radio transmission / reception apparatus having the above configuration will be described with reference to FIG. The operation of the high-frequency processing unit for the received radio signal received by the antenna is the same as that in the first embodiment described above, and thus the description thereof is omitted.

  The reception high-frequency signal S214 output from the high-frequency processing unit is input to the first reception frequency mixer 221 by the reception frequency conversion unit 202. Here, the signal is mixed with the first fixed frequency local oscillation signal S241 output from the first fixed frequency oscillator 241 of the local oscillation unit 204 and frequency-converted to become an output S221, which is input to the filter 222. At this time, an unnecessary wave is included in the output S221, and is removed by the filter 222, and then output to the second reception frequency mixer 223 as the first reception intermediate frequency signal S222.

  Subsequently, in the second reception frequency mixer 223, the first reception intermediate frequency signal S222 and the second fixed frequency local oscillation signal S242 output from the second fixed frequency oscillator 242 of the local oscillation unit 204 are obtained. After being mixed and frequency-converted, the output S223 is input to the filter 224. At this time, an unnecessary wave is included in the output S223, and after being removed by the filter 224, it is output to the third reception frequency mixer 225 as the second reception intermediate frequency signal S224.

  Further, in the third reception frequency mixer 225, the second reception intermediate frequency signal S224 and the reception variable frequency local oscillation signal S255 output from the VCO 253 of the local oscillation unit 204 are mixed, frequency-converted, and output. S225 is entered and input to the filter 226. At this time, the output S225 includes unnecessary waves, which are removed by the filter 226 and then output as the third reception intermediate frequency signal S226. Thereafter, the third reception intermediate frequency signal S226 is output from the reception frequency conversion unit 202 as a reception IF signal.

  Here, the operation of the local oscillation unit 204 that outputs a local oscillation signal to the reception frequency conversion unit 202 described above will be described in more detail. In the local oscillation unit 204, the first fixed frequency local oscillation signal S241 generated by the first fixed frequency oscillator 241 is input to the first reception frequency mixer 221 of the reception frequency conversion unit 202, and the third It is also input to the frequency mixer 243 in the oscillation circuit 245. In addition, the second fixed frequency local oscillation signal S242 generated by the second fixed frequency oscillator 242 is also input to the second reception frequency mixer 223 of the reception frequency conversion unit 202, and in the third oscillation circuit 245. To the frequency mixer 243.

  In the third oscillation circuit 245, first, in the frequency mixer 243, the first fixed frequency local oscillation signal S 241 from the first fixed frequency oscillator 241 and the second fixed frequency from the second fixed frequency oscillator 242. The local oscillation signal S242 is input and mixed, and the mixed output S243 is input to the filter 258. At this time, the mixed output S243 includes the sum frequency component and the difference frequency component of the first and second fixed frequency local oscillation signals S241 and S242. The filter 258 selects a required component from these and outputs it to the frequency mixer 251 (S259). On the other hand, the reference signal S251 generated by the reference signal oscillator 250 is input to the reference signal frequency divider 257. Then, the reference signal frequency divider 257 divides the reference signal S251 to the phase comparison frequency of the reception system and inputs it to the frequency phase comparator 256 as a reception phase comparison reference signal (S252). The reception variable frequency local oscillation signal S255, which is the output of the VCO 253, is input to the reception frequency converter 202, that is, the third frequency mixer 225 (S255) and also input to the frequency mixer 251 (S255). . At this time, the output (S256) of the frequency mixer 251 includes the sum frequency component and the difference frequency component of the output signal S259 of the filter 258 and the reception variable frequency local oscillation signal S255 as described above. These are input to the filter 252, and required components are selected and input to the VCO output signal frequency divider 255 (S257). Thereafter, the VCO output signal frequency divider 255 divides the frequency up to the phase comparison frequency of the receiving system, and the output (S258) is input to the frequency phase comparator 256. The frequency phase comparator 256 performs frequency phase comparison with the reception phase comparison reference signal (S252) described above to generate an error signal. The error signal (S253) is given a loop characteristic by the loop amplifier 254, and then input to the VCO 253 as a frequency control signal (S254).

  By doing so, the increase and decrease changes such as frequency and phase fluctuations of the first and second fixed frequency local oscillation signals S241 and S242 outputted from the first and second fixed frequency oscillators 241 and 242 are described above. Similar to the other embodiments, the frequency and phase of the received variable frequency local oscillation signal S255 controlled by the PLL cancel each other. That is, the third oscillation circuit 245 can correct (compensate) changes in the two fixed frequency local oscillation signals S241 and S242.

  Further, in the configuration on the transmission side described with reference to FIG. 11, the detailed operation description is omitted, but the two fixed frequency local oscillations are performed in the third oscillation circuit 246 on the transmission side in the same manner as described above. Changes in the signals S241 and S242 can be corrected (compensated).

  Further, as shown in FIGS. 10 and 11, the reception frequency converter 202 and the transmission frequency converter 203 are connected in the local oscillator 204, and the fixed frequency oscillators 241 and 242 are shared between the receiver side and the transmitter side. In this case, the frequency mixer 243 and the filter 258 on the receiver side also serve as the frequency mixer 244 and the filter 268 on the transmitter side, and the output of the filter 258 on the receiver side is input to the frequency mixer 261 on the transmitter side. By configuring as described above, it is possible to reduce the circuit scale and save power.

  Even if a local oscillation unit that generates four or more types of local oscillation signals (including the case of a carrier wave signal) is configured, the frequency variable signal is always one type, and the rest are fixed frequencies. By inputting all the fixed frequency signals to a PLL circuit that generates a variable frequency, changes such as fluctuations in all the fixed frequency signals can be corrected as described above.

  From the above, with the above configuration, a frequency conversion function having frequency stability can be realized with a single-circuit PLL, and a fixed-phase local oscillation signal that is a free-running oscillator is used. Noise characteristics can also be realized.

  9, 10, and 11 exemplify the case where the local oscillation signal output from the local oscillation unit 204 is used for the frequency conversion processing, but as in the second embodiment, as illustrated in FIGS. The local oscillator 204 having the above-described configuration may be incorporated in a transceiver having the demodulator 302 and the modulator 303. As a result, the local oscillation signal can be used as a modulation / demodulation carrier signal for input to the demodulator 227 and modulator 237 for modulation / demodulation processing.

  Further, as in the third embodiment, frequency dividers 271 to 276 may be provided as shown in FIGS. 14 and 15, and each local oscillation signal may be divided and input to the frequency conversion units 202 and 203. Furthermore, the frequency dividers 271 to 276 as shown in FIGS. 14 and 15 may be provided also in the configuration having the modems 227 and 237 shown in FIGS.

  As described above, in order to generate four or more local oscillation signals (carrier wave signals), the local oscillation unit is made variable with the first oscillation circuit that oscillates the fixed frequency shown in the first and second embodiments. A plurality of pairs of oscillation circuits configured by the second oscillation circuit that oscillates the frequency may be provided. That is, each oscillation circuit pair has a different fixed frequency oscillation circuit.

  The local oscillation device according to the present invention can be used for a transceiver having a frequency conversion unit and a modulation / demodulation unit. Such a transceiver (or only a receiver and a transmitter) can be used as a mobile phone terminal, a wireless LAN router, Since it can be mounted on a communication device such as a base station apparatus, it has industrial applicability.

It is a circuit diagram which shows the structure of the transmitter / receiver in a 1st Example. It is explanatory drawing which shows operation | movement of the receiver side circuit of the transmitter / receiver in a 1st Example. It is explanatory drawing which shows operation | movement of the transmitter side circuit of the transmitter / receiver in a 1st Example. It is a circuit diagram which shows the structure of the transmitter / receiver in a 2nd Example. It is explanatory drawing which shows operation | movement of the receiver side circuit of the transmitter / receiver in a 2nd Example. It is explanatory drawing which shows operation | movement of the transmitter side circuit of the transmitter / receiver in a 2nd Example. It is a circuit diagram which shows the structure of the transmitter / receiver in a 3rd Example. It is a circuit diagram which shows the structure of the transmitter / receiver in a 4th Example. It is a circuit diagram which shows the structure of the receiver side circuit of the transmitter / receiver in a 5th Example. It is explanatory drawing which shows operation | movement of the one part circuit which comprises the transmitter / receiver in a 5th Example. It is a circuit diagram which shows the structure of the transmitter side circuit of the transmitter / receiver in a 5th Example. It is a circuit diagram which shows the modification of the transmitter / receiver in 5th Example, and shows the structure of the receiver side circuit. It is a circuit diagram which shows the modification of the transmitter / receiver in 5th Example, and shows the structure of the transmitter side circuit. It is a circuit diagram which shows the modification of the transmitter / receiver in 5th Example, and shows the structure of the receiver side circuit. It is a circuit diagram which shows the modification of the transmitter / receiver in 5th Example, and shows the structure of the transmitter side circuit. It is a circuit diagram which shows the structure of the transmitter / receiver in a 1st prior art example. It is a circuit diagram which shows the structure of the modification of the transmitter / receiver in a 1st prior art example. It is a circuit diagram which shows the structure of the transmitter / receiver in the 2nd prior art example. It is a circuit diagram which shows the structure of the modification of the transmitter / receiver in a 2nd prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,101 High frequency processing part 2,202 Reception frequency conversion part 3,203 Transmission frequency conversion part 4,104,204 Local oscillation part 5,105 Antenna 11,111 Low noise amplifier 12,112 Power amplifier 13,14,22,24 , 32, 52, 62, 113, 114, 122, 124, 132, 152, 162, 222, 224, 226, 232, 234, 252, 258, 262, 268 Filter 15, 115 Duplexer 21 First reception frequency mixing 23 Second reception frequency mixer 31 Second transmission frequency mixer 33 First transmission frequency mixer 41, 141 Fixed frequency oscillator 42, 43, 142, 143 Second oscillation circuit 50, 150, 250 Reference signal Generators 51, 61, 151, 161, 243, 244, 251, 261 Frequency mixers 53, 63 153,163,253,263 VCO
54, 64, 154, 164, 254, 264 Loop amplifiers 55, 65, 155, 165, 255, 265 VCO output signal frequency dividers 56, 66, 156, 166, 256, 266 Frequency phase comparators 57, 67, 157 , 167, 257, 267 Reference signal frequency divider 71, 72, 73, 74, 171, 172, 173, 174, 271, 272, 273, 274, 275, 276 Frequency divider 102, 302 Demodulator 103, 303 Modulation Units 121, 221, 224, 226 reception frequency mixer 123, 227 demodulator 131, 231, 233, 235 transmission frequency mixer 133, 237 modulator

Claims (19)

A local oscillation device that outputs at least two local oscillation signals input to a predetermined signal processing means,
First oscillation means that is a free-running oscillator that emits a first local oscillation signal that is a fixed frequency, and second oscillation means that emits a second local oscillation signal that is a variable frequency,
The first oscillating means inputs the first local oscillation signal to the first frequency mixer provided in the predetermined signal processing means and the second oscillating means,
The second oscillating means includes mixing means for mixing the input first local oscillation signal and the second local oscillation signal, and the frequency and phase of the second local oscillation signal are input. wherein with the first local oscillation signal having a frequency and varying increase or decrease the change in increase and decrease the reverse phase input to the second frequency mixer provided in the predetermined signal processing means, wherein the output from the mixing means Controlling the phase of the sum frequency signal of the first local oscillation signal and the second local oscillation signal to be synchronized with the phase of the reference signal;
A local oscillation device characterized by that.   The second oscillating means includes a filter for selecting a sum frequency signal of the first local oscillation signal and the second local oscillation signal output from the mixing means, and a reference signal generating means for generating a reference signal. The phase of the sum frequency signal of the first local oscillation signal and the second local oscillation signal is synchronized with the phase of the reference signal, and the second local oscillation signal is synchronized with the phase of the reference frequency signal. 2. The local oscillation device according to claim 1, wherein the local oscillation device outputs the signal while changing the frequency to be constant. It said second oscillating means is a negative feedback circuit having a mixing means for mixing the said entered first local oscillation signal second local oscillation signal, according to claim 1 or, characterized in that 2. The local oscillation device according to 2. 4. The local oscillation apparatus according to claim 3, wherein the second oscillation means is a PLL circuit including the mixing means. Wherein each oscillating means, the predetermined signal processing means preset the each local oscillation signal output by the minute division number division to a divider provided respectively, 1 to claim, characterized in that 5. The local oscillation device according to any one of 4 above. Claim 1 phase noise level of the first local oscillation signal by the first oscillator means is emitted, which is lower than the phase noise level of the second local oscillation signal and the second oscillating means emitted, characterized in that The local oscillation device according to any one of 1 to 5 . The frequency of the first local oscillation signal generated by the first oscillation means is at least x times that of the second local oscillation signal generated by the second oscillation means (x: shown in Equation 1). The local oscillation device according to claim 1 .
In addition to the first oscillating means, one or a plurality of other fixed frequency oscillating means which are self-running oscillators that output a local oscillation signal having a fixed frequency to the predetermined signal processing means,
The second oscillation means inputs a local oscillation signal output from one or more other fixed frequency oscillation means and a first local oscillation signal output from the first oscillation means. Mixing means is provided, and the frequency and phase of the second local oscillation signal are increased or decreased in frequency and phase between the local oscillation signal and the first local oscillation signal input from the other fixed frequency oscillation means. an inverse and outputs by changing increase or decrease in the local oscillation signal and the first local oscillation signal and the second reference phase of the sum frequency signal and the local oscillation signal from the other fixed frequency oscillating means Control to synchronize with the phase of the signal,
The local oscillation device according to claim 1, wherein: The pair of the first oscillating means and the second oscillating means for outputting each of the local oscillation signals to the predetermined signal processing means is provided separately or in pairs. The local oscillation device according to any one of 1 to 8 . The local oscillation device according to any one of claims 1 to 9 ,
A reception signal processing device that performs signal processing such as frequency conversion processing and demodulation processing on a signal received from an antenna using each local oscillation signal output from the local oscillation device;
A receiver comprising: The received signal processing device mixes the first local oscillation signal output from the local oscillation device with a signal received from the antenna, converts the frequency, and outputs a first intermediate frequency signal. A second frequency mixer that mixes the second local oscillation signal output from the local oscillation device with the first intermediate frequency signal, converts the frequency, and outputs a second intermediate frequency signal; 11. The receiver according to claim 10, further comprising: The received signal processing device includes: a frequency mixer that mixes the first local oscillation signal output from the local oscillation device with a signal received from the antenna, converts the frequency, and outputs an intermediate frequency signal; and the local oscillation 11. The receiver according to claim 10 , further comprising: a demodulator that mixes and demodulates the second local oscillation signal output from a device with the intermediate frequency signal and outputs a reception baseband signal. The local oscillation device according to any one of claims 1 to 9 ,
A transmission signal processing device that performs signal processing such as frequency conversion processing and modulation processing for generating a signal to be transmitted from an antenna, using each local oscillation signal output from the local oscillation device;
A transmitter characterized by comprising: The transmission signal processing device mixes the second local oscillation signal output from the local oscillation device into a first intermediate frequency signal, converts the frequency, and outputs a second intermediate frequency signal. And a second frequency mixer for mixing the first local oscillation signal output from the local oscillation device with the second intermediate frequency signal and converting the frequency to output a transmission signal transmitted from the antenna 14. The transmitter according to claim 13, further comprising: The transmission signal processing device includes a modulator that mixes and modulates the second local oscillation signal output from the local oscillation device with a transmission baseband signal and outputs an intermediate frequency signal, and is output from the local oscillation device. 14. The transmission according to claim 13 , further comprising: a frequency mixer that mixes the first local oscillation signal with the intermediate frequency signal and converts the frequency to output a transmission signal transmitted from the antenna. Machine. A receiver according to any one of claims 10 to 12 and a transmitter according to any one of claims 13 to 15 ,
The local oscillation device that constitutes the receiver and the local oscillation device that constitutes the transmitter are configured to share a circuit.
A transceiver characterized by that. The first oscillation means in the local oscillation device constituting the receiver and the first oscillation means in the local oscillation device constituting the transmitter are configured to share the same oscillation means.
The transceiver according to claim 16 . A receiver according to any one of claims 10 to 12, a transmitter according to any one of claims 13 to 15 , or a transceiver according to claim 16 or 17 , comprising: Communication equipment. A receiver according to any one of claims 10 to 12, a transmitter according to any one of claims 13 to 15 , or a transceiver according to claim 16 or 17 , comprising: Mobile phone terminal.