JP3968357B2 - Vector modulation signal generator - Google Patents

Description

  The present invention relates to a vector modulation signal generator for outputting a quadrature modulation signal (vector modulation signal) generated by quadrature modulation of a carrier wave with a baseband signal, and in particular, a vector capable of calibrating the output level of a quadrature modulation signal with high accuracy. The present invention relates to a modulation signal generator.

  Generally, ALC (Automatic Level Control) is used to stabilize or calibrate the output level of a signal generator in IF (intermediate frequency) band and RF (radio frequency) band. In the case of a vector modulation signal generator, the envelope amplitude may fluctuate in a quadrature modulation signal generated by quadrature modulation of a carrier wave with a baseband signal, and the fluctuation is not always sinusoidal. If the output level is calibrated by directly applying ALC to the quadrature modulation signal, effective value detection of the quadrature modulation signal is particularly difficult in the RF band, and it is difficult to accurately detect the output level. Therefore, conventionally, as a calibration signal, a carrier wave is orthogonally modulated by DC (direct current) to generate a CW (continuous wave) signal, and this CW signal is subjected to ALC (ALC on) to calibrate the output level. Later, the ALC is turned off to maintain this calibrated state, and the modulation signal is switched from the calibration signal to the baseband signal to generate a quadrature modulation signal. There has been a vector modulation signal generating device adapted to output. (For example, see Patent Document 1).

JP 2003-43084 A

  A schematic configuration of this type of vector modulation signal generator is shown in FIG. The baseband signal generator 1 generates a baseband signal that is a modulation signal (data to be transmitted) of the vector modulation signal generator and outputs the baseband signal to the first switching unit 3. Further, the calibration signal generating means 2 generates a calibration signal having a predetermined DC voltage for generating a CW signal used for calibration of the output level of the vector modulation signal generator, and the first switching means 3. Output to. The first switching unit 3 switches the baseband signal and the calibration signal according to the switching signal a from the control unit 10 and outputs the switched signal to the quadrature modulation unit 4. The quadrature modulation unit 4 performs quadrature modulation on a carrier wave (IF band) using a baseband signal or calibration signal as an I signal, a Q signal input from the first switching unit 3, and performs quadrature modulation that is an IF band signal. A signal or CW signal is generated and output to the level varying means 5.

  The level varying means 5 attenuates the level (amplitude) of the IF band signal (orthogonal modulation signal or CW signal) input from the quadrature modulation means 4 according to the control signal and outputs the attenuated signal to the RF circuit 6. The RF circuit 6 includes a mixer, a local oscillator, a filter, an amplifier, and the like (not shown). The RF circuit 6 receives an IF band signal output from the quadrature modulation means 4 via the level variable means 5 and receives an RF band signal. Convert to and output. Thus, when the above-described baseband signal is input to the quadrature modulation means 4, the RF band quadrature modulation signal is output from the RF circuit 6 to the outside as an output signal of the vector modulation signal generator.

  The detector 7a receives and detects a part of the RF band signal output from the RF circuit 6 as a feedback signal for applying ALC, and outputs the detected voltage to the comparator 7b. The comparator 7b compares the detection signal input from the detector 7a with the reference voltage input from the reference voltage generator 7c, and outputs the error signal to the loop filter 7d. The loop filter 7d is a filter that determines the response band of the ALC loop, limits the band of the error signal input from the comparator 7b, and outputs it to the second switching means 9 as a control signal for the level variable means. The reference voltage generator 7 c generates and outputs a reference voltage specified by the level setting signal c input from the control means 10. The output level to be stabilized by the ALC loop is set by this reference voltage. The detector 7a, comparator 7b, reference voltage generator 7c, and loop filter 7d constitute feedback means 7.

  The sample hold means (S / H) 8 samples and holds the feedback voltage output from the loop filter 7 d, that is, the feedback means 7 in accordance with the hold signal b input from the control means 10, and then uses this hold voltage as the second voltage. Output to the switching means 9. The second switching means 9 switches the feedback voltage and the hold voltage according to the switching signal a from the control means 10 and outputs it to the level variable means 5 as a control signal.

  When the calibration signal is input to the quadrature modulation unit 4, the control unit 10 inputs the feedback voltage to the level variable unit 5 to form an ALC loop, and the baseband signal is quadrature modulated. When being input to the means 4, the switching signal a is output to the first switching means 3 and the second switching means 9 so that the above-described hold voltage is input as a control signal for the level variable means 5. The sample hold means 8 samples and holds the feedback voltage after the ALC loop is formed and the output level is stabilized, and outputs a hold signal b for holding the hold voltage. Further, a level setting signal c for setting the above-described reference voltage is output to the reference voltage generating means 7c.

In the conventional vector modulation signal generating apparatus configured as described above, the output level, that is, the level of the RF band quadrature modulation signal output from the RF circuit 6 is calibrated by the following procedure.
(1) A calibration signal is input to the quadrature modulation unit 4, a CW signal is output from the quadrature modulation unit 4, and a feedback voltage of the feedback unit is input as a control signal of the level variable unit 5 to form an ALC loop. Thus, the first switching means 3 and the second switching means 9 are switched by the switching signal a. Thereby, the output level of the RF band CW signal is calibrated at the output level set by the reference voltage.

(2) The output signal of the feedback means is sampled and held by the holding signal b and the voltage is held. Thereby, the attenuation amount of the level varying means 5 calibrated with the CW signal is maintained.

(3) The switching signal a so that the baseband signal is input to the quadrature modulation unit 4, the quadrature modulation signal is output from the quadrature modulation unit 4, and the hold voltage is input as the control signal of the level varying unit 5. Thus, the first switching means 3 and the second switching means 9 are switched. As a result, the ALC is turned off, the calibrated attenuation amount is set in the level variable means 5, and the output level of the RF band quadrature modulation signal is set to the output level of the RF band CW signal set by the reference voltage. (Same as (1) above) and calibration is completed. In order to make the output level of the quadrature modulation signal coincide with the output level of the CW signal, the amplitude (effective value) of the baseband signal for generating the quadrature modulation signal and the DC voltage for generating the CW signal in advance. Together.

  However, such a conventional vector modulation signal generator has the following problems. That is, when a calibration signal is input to the quadrature modulation means and a CW signal for output level calibration is generated by the quadrature modulation means, a DC voltage is used as the calibration signal, so that the same CW signal as the carrier wave is generated. Will be output. As a result, the carrier leakage (leakage of the carrier wave to the output side) of the quadrature modulation means and the CW signal are always vector-synthesized with a constant phase relationship and output from the quadrature modulation means. Then, since the ALC is operated by using the CW signal (the signal combined with the carrier leak) output from the quadrature modulation means and the output level is calibrated, the carrier leak causes an output level calibration error. Specifically, if the carrier leak is −40 dB and the CW signal and the carrier leak have the same phase, the total power is obtained as an amplitude addition (detected by the detector), so the output level error is 0.1 dB. Become. Further, when the carrier leak is −30 dB, an error of about 0.3 dB occurs. As described above, when DC is input to the quadrature modulation means in order to generate the CW signal for output level calibration, there is a problem that an output level calibration error occurs due to carrier leak of the quadrature modulation means.

  An object of the present invention is to solve these problems and to provide a vector modulation signal generator capable of calibrating the output level with high accuracy.

In order to solve the above-mentioned problems, in the vector modulation signal generator according to claim 1 of the present invention, a baseband signal generation means (1) and an orthogonal modulation means (4) for orthogonally modulating the baseband signal based on a local signal. A calibration signal generating means (2) for outputting a calibration signal for calibrating the output level from the quadrature modulation means, and a quadrature modulation signal varied by changing the output level from the quadrature modulation means Level variable means (5) for outputting, feedback means (7) for generating and outputting a feedback voltage for setting the output level of the varied quadrature modulation signal to a predetermined level, and output from the feedback means (7) Sample and hold means (8) for sampling and holding the feedback voltage to be output and outputting the sampled and held voltage in order to maintain the attenuation of the level variable means (5) Comprising a, in the vector modulated signal generator to form an ALC loop by inputting the feedback voltage to the level variable unit (5) of said feedback means (7), the calibration signal generation means (2), the The calibration signal is a complex sine wave signal having the same amplitude as that of the I signal and the Q signal input to the quadrature modulation means and a phase difference of 90 degrees, and the frequency of the complex sine wave signal is equal to that of the ALC loop. complex sine wave signal generating means (24) der comprising means for generating a calibration complex sine wave signal is a high frequency of outside response band is, the feedback voltage when the complex sine wave signal for the calibration and the quadrature modulation The output level is calibrated with the sampled and held voltage .

Further, a vector modulated signal generator of claim 2, a baseband signal generating means for generating a baseband signal (1), the calibration signal generation means for generating a calibration signal for calibrating and (2), wherein First switching means (3) for switching and outputting a baseband signal and the calibration signal, and quadrature modulation means (4) for orthogonally modulating and outputting a carrier wave by a signal input from the first switching means Level varying means (5) for receiving the quadrature modulation signal output from the quadrature modulation means and changing the level of the quadrature modulation signal according to the control signal and outputting the quadrature modulation output from the level variable means A feedback power for setting the output level of the quadrature modulation signal output from the level varying means to a predetermined level based on a detection voltage obtained by receiving a part of the signal and detecting the signal. A feedback means for outputting to generate (7), wherein the sample holding means for a feedback voltage to the sample and hold (8) output from the feedback means, the hold voltage and the feedback means which is outputted from the sample hold means ALC by a second and a switching means (9), said feedback means, said second switching means and said level changing means for outputting as a control signal of the level changing means switches the feedback voltage output from When a loop is formed and the quadrature modulation means is quadrature modulated by the calibration signal, the feedback voltage is input to the level variable means, the output level is stabilized by the ALC loop, and the when the quadrature modulation means are quadrature modulated by the baseband signal, the output level by the ALC loop stabilization The hold voltage which the sample and hold means for the feedback voltage and sample-and-hold output from said feedback means when had outputted is inputted to the level variable unit as a control signal, so as to calibrate the output level, the In the vector modulation signal generating apparatus comprising a control means (10) for switching the first switching means and the second switching means, the calibration signal generating means inputs the calibration signal to the quadrature modulation means. A complex sine wave signal in which the amplitude of the I signal and the Q signal are the same and the phase difference is 90 degrees, and the frequency of the complex sine wave signal is a high frequency outside the response band of the ALC loop . It is a complex sine wave signal generation means (24) including a means for generating a complex sine wave signal.

According to a third aspect of the present invention, there is provided the vector modulation signal generator according to the first aspect , wherein the clock generation means (21) for outputting a clock and the baseband signal generation means by dividing the clock. First dividing means (22) for outputting, and second dividing means (23) for dividing the clock and outputting it to the complex sine wave signal generating means, wherein the control means includes the first dividing means (22) . In addition to the first switching means and the second switching means, a frequency setting signal for setting a frequency generated by the clock generation means and a frequency dividing ratio for dividing the clock are set in the first frequency dividing means. It is a control means (25) which outputs the division ratio setting signal to perform.
According to a fourth aspect of the present invention, in the vector modulated signal generator according to the first to third aspects, the means for generating the calibration complex sine wave signal stores the calibration complex sine wave signal. It is characterized by being a memory.

  In the vector modulation signal generator according to claim 1 or 2 of the present invention, as a calibration signal, a complex sine wave in which the amplitude of the I signal and the Q signal input to the quadrature modulation means is the same and the phase difference is 90 degrees. The CW signal for output level calibration is generated by the quadrature modulation means using a complex sine wave signal that is a signal and the frequency of the complex sine wave signal is higher than the response band of the ALC loop. The calibration error of the output level caused by the carrier leak can be reduced, and the output level can be calibrated with high accuracy.

  In the vector modulation signal generator according to claim 3 of the present invention, the clock generation means for supplying a clock to each of the baseband signal generation means or the complex sine wave signal generation means is made common, and the clock is divided to generate each signal. Since each of the frequency dividers output to the means is provided, the continuity of the timing of the baseband signal output from the baseband signal generation means before and after the ALC calibration can be maintained. As a result, when the object to be measured is measured while synchronizing the phase of the output signal of the signal generator, for example, in error rate measurement, continuity is maintained before and after ALC calibration even when ALC calibration is performed during measurement. Therefore, when restarting the measurement, it is not necessary to start the measurement from the beginning, and it can be restarted from the point of interruption. Further, the circuit scale can be reduced by sharing the clock generating means.

  Examples of the present invention will be described below.

  FIG. 1 shows the configuration of the vector modulation signal generating apparatus according to the first embodiment of the present invention. The same elements as those of the conventional vector modulation signal generator are denoted by the same reference numerals, and detailed description thereof is omitted. The clock generation unit 21 generates a clock of, for example, 100 MHz to 200 MHz in accordance with the frequency setting signal d input from the control unit 25 and outputs it to the first frequency dividing unit 22 and the second frequency dividing unit 23. The first frequency dividing means 22 divides the clock input from the clock generating means 21 into 1/2, 1/4, 1/8, for example, according to the frequency division ratio setting signal e input from the control means 25. Then, the signal is output to the baseband signal generating means 1. The second frequency divider 23 divides the clock input from the clock generator 21 into, for example, 1/8 and outputs the result to the complex sine wave signal generator 24.

  The baseband signal generating means 1 reads out the modulation signal (data to be transmitted) stored in the memory in synchronization with the clock input from the first frequency dividing means 22, and uses the read data as the baseband signal. To the first switching means 3. The complex sine wave signal generating means 24, which is a calibration signal generating means, synchronizes with the clock input from the second frequency dividing means 23 and has a complex sine wave signal (having the same amplitude) stored in the memory. The I and Q signals having a phase difference of 90 degrees are read out, and the read out complex sine wave signal is output to the first switching means 3 as a calibration signal. Note that the output frequency of the complex sine wave signal is higher than the response band of the ALC loop. For example, 16 MHz oversampling is about 1 MHz, which is higher than the response band of the ALC loop (about 100 KHz).

The first switching unit 3 switches the baseband signal and the calibration signal according to the switching signal a from the control unit 25 and outputs the switched signal to the quadrature modulation unit 4. The quadrature modulation unit 4 quadrature modulates a carrier wave (IF band) with a baseband signal or a calibration signal (complex sine wave signal) input from the first switching unit 3 as an I signal, Q signal, and IF band The quadrature modulation signal or the CW signal, which is the above signal, is generated and output to the level varying means 5. Here, when the complex sine wave signal (frequency F ₁ ) is input to the quadrature modulation unit 4 (carrier frequency F ₀ ), the complex sine wave signal, the CW signal generated by the quadrature modulation unit 4, and the quadrature modulation unit The spectrum relationship of the carrier leak (frequency F ₀ ) 4 is shown in FIG. _{One of} (F ₀ −F ₁ ) and (F ₀ + F ₁ ) is generated as the CW signal. Further, the relationship between the CW signal and the carrier leak is that the vector due to the carrier leak always rotates at an angular velocity corresponding to the frequency F ₁ with respect to the phase of the CW signal, and the envelope of the output signal of the quadrature modulation means Amplitude fluctuations are generated in the line.

  As described above, the baseband signal and the calibration signal are switched and input to the quadrature modulation unit 4. However, the baseband signal generation unit 1 receives the calibration signal from the quadrature modulation unit 4. The baseband signal is output from the quadrature modulation unit 4 before and after switching to the calibration signal when the baseband signal is next input to the quadrature modulation unit 4. Thus, the continuity of the timing of the orthogonal modulation signal is maintained.

  The level variable means 5 attenuates the level (amplitude) of the signal input from the quadrature modulation means 4 according to the control signal and outputs the attenuated signal to the RF circuit 6. The RF circuit 6 includes a mixer, a local oscillator, a filter, an amplifier, and the like (not shown). The RF circuit 6 receives a signal output from the level varying means 5 and converts it into an RF band signal and outputs it. Thus, when the above-described baseband signal is input to the quadrature modulation means 4, the RF band quadrature modulation signal is output from the RF circuit 6 to the outside as an output signal of the vector modulation signal generator of the present invention.

  The detector 7a receives and detects a part of the RF band signal output from the RF circuit 6 as a feedback signal for applying ALC, and outputs the detected voltage to the comparator 7b. The comparator 7b compares the detection signal input from the detector 7a with the reference voltage input from the reference voltage generator 7c, and outputs the error signal to the loop filter 7d. The loop filter 7d is a filter that determines the response band of the ALC loop, limits the band of the error signal input from the comparator 7b, and outputs it to the second switching means 9 as a control signal for the level variable means. The response band of the ALC loop is determined in consideration of the output level switching time, the frequency of the aforementioned complex sine wave signal (calibration signal), and the like. For example, as shown in FIG. 3, the output level switching time is 10 μs, the frequency of the complex sine wave signal is about 1 MHz, and in this case, the response band is about 100 KHz.

  The reference voltage generator 7c generates and outputs a reference voltage specified by the level setting signal c input from the control means 25. The output level to be stabilized by the ALC loop is set by this reference voltage. The detector 7a, comparator 7b, reference voltage generator 7c, and loop filter 7d constitute feedback means 7.

  The sample hold means (S / H) 8 samples and holds the feedback voltage output from the feedback means 7 with the pulse of the hold signal b input from the control means 25, and this hold voltage is supplied to the second switching means 9. Output. As the sample and hold means 8, for example, an analog configuration in which an analog switch and a capacitor are combined, a digital configuration in which an A / D converter and a D / A converter are combined, or the like can be used. The second switching means 9 switches the feedback voltage and the hold voltage with the pulse of the switching signal a from the control means 25 and outputs it to the level variable means 5 as a control signal.

  The control means 25 forms an ALC loop by inputting the feedback voltage of the feedback means as the control signal of the level variable means 5 when the calibration signal is inputted to the quadrature modulation means 4, and the above-mentioned base The switching signal a is changed to the first switching means 3 and the second switching means 9 so that the above-mentioned hold voltage is inputted as a control signal of the level variable means 5 when the band signal is inputted to the quadrature modulation means 4. Output to. The sample hold means 8 samples and holds the feedback voltage after the ALC loop is formed and the output level is stabilized, and outputs a hold signal b for holding the voltage. FIG. 4 shows the timing relationship between the switching signal a and the holding signal b. For example, in the case of level calibration accompanying a change in the frequency of the carrier wave input to the quadrature modulation means 4, the switching signal a is generated simultaneously with the change in the carrier frequency as shown in FIG. It is output to the first switching means 3 and the second switching means 9. Further, the reference voltage generator 7c, the clock generation means 21 and the first frequency dividing means 22 are supplied with a level setting signal c, a frequency setting signal d and a frequency division ratio setting signal e for setting the above-mentioned reference voltage, Output each.

  In the vector modulation signal generator of the present invention configured as described above, the output level, that is, the level of the RF band quadrature modulation signal output from the RF circuit 6 is calibrated by the following procedure. (1) A calibration signal is input to the quadrature modulation unit 4, a CW signal is output from the quadrature modulation unit 4, and a feedback voltage of the feedback unit is input as a control signal of the level variable unit 5 to form an ALC loop. Thus, the first switching means 3 and the second switching means 9 are switched by the switching signal a. As a result, the output level of the RF band CW signal is stabilized at the output level set by the reference voltage, and the output level is calibrated.

(2) The output signal of the feedback means is sampled and held by the holding signal b and the voltage is held. Thereby, the attenuation amount of the level varying means 5 calibrated with the CW signal is maintained.

(3) The switching signal a so that the baseband signal is input to the quadrature modulation unit 4, the quadrature modulation signal is output from the quadrature modulation unit 4, and the hold voltage is input as the control signal of the level varying unit 5. Thus, the first switching means 3 and the second switching means 9 are switched. As a result, the ALC is turned off and the calibrated attenuation amount is set, and the output level of the RF band quadrature modulation signal is set to the output level of the RF band CW signal set by the reference voltage ((1) above). ) And calibration is completed. In order to make the output level of the quadrature modulation signal coincide with the output level of the CW signal, the amplitude (effective value) of the baseband signal for generating the quadrature modulation signal and the complex sine for generating the CW signal are set in advance. The amplitude (effective value) of the wave signal is matched.

  In the vector modulation signal generator of the present invention configured as described above, as described above, the amplitude of the I signal and the Q signal input to the quadrature modulation means 4 is the same and the phase difference is 90 degrees as the calibration signal. And a complex sine wave signal whose frequency is higher than the response band of the ALC loop, the output level calibration CW signal is converted by the quadrature modulation means 4. It was made to generate. As a result, even if there is a carrier leak in the quadrature modulation means 4, the carrier leak and the CW signal are not always vector-synthesized with a constant phase relationship, that is, the carrier leak phase is always rotated when the phase of the CW signal is used as a reference. Therefore, the total power is obtained as power addition, and an error (calibration error) in the output level as generated by the amplitude addition of the prior art hardly occurs. In addition, the amplitude fluctuation that occurs in the envelope due to the difference between the CW signal and the carrier leak frequency is set to be higher than the response band of the ALC loop (determined by the frequency of the complex sine wave signal). There is no power level error that occurs when is within the response band of the ALC loop. Therefore, there is almost no output level error due to carrier leakage. Specifically, when the carrier leak is −30 dB to −40 dB, the output level error is about 0 dB.

  Further, since the clock frequency-divided by the first frequency dividing means 22 having a variable frequency dividing ratio is input to the baseband signal generating means 1, the frequency of the clock input to the baseband signal generating means 1 is variable. The range, that is, the frequency variable range of the baseband signal generated by the baseband signal generating means 1 can be widened. In addition, since the clock frequency-divided by the frequency dividing means 23 having a fixed frequency dividing ratio is input to the complex sine wave signal generating means 24, the frequency range of the clock input to the complex sine wave signal generating means 24, That is, it is possible to prevent the frequency range of the complex sine wave signal generated by the complex sine wave signal generating unit 24 from becoming wider than the band restricted by the relationship with the response band of the ALC loop. In addition, since the clock input to the baseband signal generation unit 1 and the clock input to the complex sine wave signal generation unit 24 are both used by dividing the clock of the clock generation unit 21, the baseband signal It is possible to prevent spurious contamination in the output signal due to leakage on circuit mounting, that is, deterioration of output signal purity, which is likely to occur when the complex sine wave signal is not synchronized.

  Further, the baseband signal generating means 1 operates continuously even while the calibration signal is input to the quadrature modulation means 4, and then the baseband signal is input to the quadrature modulation means 4. Sometimes, the continuity of the timing of the quadrature modulation signal output from the quadrature modulation means 4 is maintained before and after switching to the calibration signal. This makes it possible to perform a timing synchronization test or the like of the repeater or receiver to be measured.

The figure which shows the structure of Example 1 of this invention. The figure for demonstrating operation | movement of the orthogonal modulation means of Example 1 of this invention. The figure which shows the response band of the ALC loop of Example 1 of this invention The figure for demonstrating the operation | movement of ALC of Example 1 of this invention. The figure which shows schematic structure of a prior art example

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Baseband signal generation means, 2 ... Calibration signal generation means, 3 ... First switching means, 9 ... Second switching means, 4 ... Orthogonal modulation means, 5. ..Level variable means, 6 ... RF circuit, 7 ... feedback means, 7a ... detector, 7b ... comparator, 7c ... reference voltage generator, 7d ... loop filter, 8 ... sample hold means 10, 25 ... control means, 21 ... clock generating means, 22 ... first frequency dividing means, 23 ... second frequency dividing means, 24 ... Complex sine wave signal generation means.

Claims (4)

Baseband signal generating means (1), orthogonal modulation means (4) for orthogonally modulating the baseband signal based on the local signal, and calibration for outputting a calibration signal for calibrating the output level from the orthogonal modulation means Signal generating means (2), level variable means (5) for changing the output level from the quadrature modulation means and outputting it as a variable quadrature modulation signal, and the output level of the variable quadrature modulation signal being predetermined. The feedback means (7) for generating and outputting a feedback voltage for setting the level of the current and the feedback voltage output from the feedback means (7) are sampled and held, and the attenuation of the level variable means (5) is maintained. And a sample hold means (8) for outputting the sampled and held voltage to input the feedback voltage of the feedback means (7) to the level variable means (5). In vector modulation signal generator to form an ALC loop Rukoto,
The calibration signal generating means (2) is a complex sine wave signal in which the amplitude of the I signal and the Q signal input to the quadrature modulation means is the same and the phase difference is 90 degrees as the calibration signal, and the complex sine wave signal generating means (24) including means for frequency of the complex sinusoidal signal to generate the calibration complex sine wave signal which is a response band of high frequencies of the ALC loop der is, the calibration complex sine A vector modulation signal generating apparatus characterized in that the output level is calibrated by a voltage obtained by sampling and holding the feedback voltage when the wave signal is orthogonally modulated . A baseband signal generating means for generating a baseband signal (1), switches the calibration signal generation means for generating a calibration signal for the calibration (2), the baseband signal and said calibration signal output First switching means (3), quadrature modulation means (4) for orthogonally modulating a carrier wave with a signal input from the first switching means, and an orthogonal modulation signal output from the orthogonal modulation means In response, the level varying means (5) for changing the level of the quadrature modulation signal with a control signal and outputting it, and receiving a part of the quadrature modulation signal outputted from the level varying means, detects the signal. Feedback means (7) for generating and outputting a feedback voltage for setting the output level of the quadrature modulation signal output from the level variable means to a predetermined level based on the detection voltage obtained in this manner, and the feedback hand From the the sample-hold means for the feedback voltage to the sample and hold (8) output, the feedback voltage and the level changing means switches the output from the hold voltage and the feedback means which is outputted from the sample hold means and a second switching means for outputting as a control signal (9), said feedback means, said and ALC loop is formed by the second switching means and said level changing means, said quadrature modulating means for the calibration when it is orthogonally modulated by a signal, the said output level feedback voltage by type ALC loop to said level varying means is stabilized, and the quadrature modulating means is directly 交変 tone by said baseband signal when you are, the return output from the feedback means when the output level has been stabilized by the ALC loop The hold voltage is input to the level varying means as the control signal is the sample and hold means that samples and holds the voltage outputted to calibrate the output level, the first switching means and said second switching means In a vector modulation signal generator comprising control means (10) for switching,
The calibration signal generating means is a complex sine wave signal having the same amplitude as that of the I signal and Q signal input to the quadrature modulation means and a phase difference of 90 degrees as the calibration signal, and the complex sine A vector-modulated signal generator comprising a complex sine wave signal generating means (24) including means for generating a calibration complex sine wave signal whose frequency is higher than the response band of the ALC loop. apparatus. A clock generating means (21) for outputting a clock; a first frequency dividing means (22) for dividing the clock and outputting it to the baseband signal generating means; and the complex sine wave by dividing the clock. And a second frequency dividing means (23) for outputting to the signal generating means, wherein the control means determines the frequency generated by the clock generating means in addition to the first switching means and the second switching means. The control means (25) for outputting a frequency setting signal to be set and a frequency dividing ratio setting signal for setting a frequency dividing ratio for dividing the clock in the first frequency dividing means. 2 Symbol placement vector signal generator apparatus. 4. The vector signal generator according to claim 1, wherein the means for generating the calibration complex sine wave signal is a memory storing the calibration complex sine wave signal.

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