JP3788222B2 - High frequency IC circuit - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention particularly relates to a high-frequency IC circuit suitable for a high-frequency front-end IC that converts a high-frequency signal of several hundred MHz to several GHz into a low-frequency signal of about several MHZ called a baseband signal.
[0002]
[Prior art]
Conventionally, a high-frequency IC that downconverts a high-frequency signal to a baseband signal by two-stage frequency conversion has been externally provided with a high-order bandpass filter having a steep selection characteristic. In many cases, a band-pass filter or a low-pass filter provided after the frequency converter of the second stage is also externally attached.
[0003]
Japanese Laid-Open Patent Publication No. 5-90992 discloses a wireless communication apparatus that improves transmission / reception characteristics by suppressing noise generated when a filter is used and reducing nonlinear distortion.
[0004]
[Problems to be solved by the invention]
In conventional high-frequency front-end ICs, filters are provided externally before and after each frequency converter, which increases the number of parts when the device is assembled, hindering the overall size, weight, and cost of the device. It was. In addition, there is a problem that an unnecessary external signal is picked up or an unnecessary signal is radiated by signal exchange between the high frequency IC and the external filter.
[0005]
It is necessary to provide a high-order bandpass filter having a steep selection characteristic between the first-stage frequency converter and the second-stage frequency converter. In the conventional circuit system, it is built in the IC. It was difficult and the parts cost of the filter was high.
[0006]
The present invention has been made in view of the above circumstances, and can reduce the number of parts to reduce size and weight, reduce costs, facilitate mounting, and suppress mixing and radiation of unnecessary signals. An object of the present invention is to provide a high-frequency IC circuit that can be used.
[0007]
[Means for Solving the Problems]
  The invention according to claim 1 for solving the above-described problem is an IC circuit for high-frequency reception having a first-stage frequency converter and a second-stage frequency converter,The frequency converter in the first stage forms an image rejection mixer, the frequency converter in the second stage forms a quadrature down-conversion mixer, and a complex filter provided before the frequency converter in the first stage is integrated in the IC. Built in.
[0013]
  Claim2The described invention is a circuit of a high-frequency receiving IC having a first-stage frequency converter and a second-stage frequency converter, and the first-stage frequency converter forms an image rejection mixer, A complex filter provided before the first stage frequency converter is built in the IC, and only the in-phase component I signal or quadrature component Q signal is output from the first stage frequency converter to convert the second stage frequency. The unit is configured as a single mixer.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
  Before describing embodiments according to the present invention, reference examples related to the present invention will be described.FIG.Is the first1Reference exampleFIG. 2 is a frequency characteristic diagram of a complex filter provided in the high frequency IC of FIG. 1, and FIG. 3 is an explanatory diagram of input / output signals of the second-stage frequency conversion unit and complex filter in FIG. The following is the first using these figures.Reference exampleWill be explained.
[0017]
The high frequency IC circuit shown in FIG. 1 includes a GPS antenna 1, a band pass filter (BPF) 2, a high frequency IC 10 for GPS signals connected to the GPS antenna 1 through the band pass filter 2, and a high frequency IC 10 An external band pass filter 3 is provided.
[0018]
The high frequency IC 10 includes a low noise amplifier 101 that amplifies the signal (GPS signal) S2 from the band pass filter 2, a crystal oscillator 102, and a frequency of f._LO1The voltage controlled oscillator (VCO) 103 that generates the first local oscillation frequency signal S103 and the first local oscillation frequency signal S103 divided by a frequency of 1 / N to obtain a frequency f_LO2From the frequency divider 104 for obtaining the second local oscillation frequency signal S104, the frequency divider 105 for dividing the second local oscillation frequency signal S104 to a frequency of 1 / M to obtain the signal S105, and the frequency divider 105 The phase comparator 106 that controls the output of the voltage controlled oscillator 103 so that the frequency of the signal S105 matches the frequency of the oscillation output of the crystal oscillator 102, The low-pass filter 107 interposed between the phase comparator 106 and the voltage controlled oscillator 103 and the first local oscillation frequency signal S103 are input, and the frequency of the signal S2 amplified by the low noise amplifier 101 is f._IF1A first-stage frequency converter 108 that outputs the first intermediate frequency (IF) signal S108 after down-conversion, and a buffer amplifier 109 interposed between the frequency converter 108 and the input of the bandpass filter 3. And a complex filter unit 110 connected to the output of the bandpass filter 3 and the output of the frequency divider 104.
[0019]
The complex filter unit 110 receives the signal from the frequency divider 104 and converts the signal from the bandpass filter 3 into a frequency f._IF2The second-stage frequency converters 111 and 112 that down-convert and output to the second intermediate frequency signal S11, the band-pass filter 113 connected to the outputs of these frequency converters 111 and 112, and the band-pass filter 113 And buffer amplifiers 114 and 115 connected to the outputs of the frequency converters 111 and 112, respectively, and A / D converters 116 and 117 connected to the outputs of the buffer amplifiers 114 and 115, respectively. .
[0020]
The high frequency IC circuit having the above configuration will be further described. A GPS signal received by the GPS antenna 1 is input to the high frequency IC 10 via the external band pass filter 2. The input signal S2 is amplified by the low noise amplifier 101 and input to the frequency conversion unit 108. Further, the first local oscillation frequency signal S103 from the voltage controlled oscillator 103 is input to the frequency converter 108. Then, in the frequency conversion unit 108, the signal S2 is down-converted to the first intermediate frequency signal S108.
[0021]
The first intermediate frequency signal S108 is input to the external band-pass filter 3 via the buffer amplifier 15, and the output signal is input to the frequency converters 111 and 112 and down-converted to the second intermediate frequency signal S11. The More specifically, the frequency converters 111 and 112 use the second local oscillation frequency signal S104 having a phase difference of 90 degrees to use the second intermediate between the in-phase component (I signal) and the quadrature component (Q signal). A frequency signal is created, and the mirror frequency can be suppressed by a subsequent filter. Unnecessary components are removed from the second intermediate frequency signal by the bandpass filter 113, and the in-phase component (I signal) and the quadrature component (Q signal) are passed through the buffer amplifiers 114 and 115 and the A / D converters 116 and 117. Is output outside the high-frequency IC 10.
[0022]
By the way, the first and second local oscillation frequency signals S103 and S104 are generated by a phase locked loop (PLL). That is, the oscillation output of the crystal oscillator 102 is input to the phase comparator 106, and the oscillation output of the voltage controlled oscillator 103 is compared with a signal obtained by N × M frequency division by the frequency dividers 104 and 105, and voltage control is performed by the comparison output. The oscillation frequency of the oscillator 103 is controlled. As a result, the first local oscillation frequency signal S103 of the voltage controlled oscillator 103 is frequency-divided to a frequency of 1 / N by the frequency divider 104 to become a second local oscillation frequency signal S104, which is 1 / M of frequency by the frequency divider 105. The frequency is divided to coincide with the frequency of the crystal oscillator 102.
[0023]
  Next, the firstReference exampleThe features of will be described. FirstReference exampleThen, as shown in FIG. 1, the bandpass filter 3 provided between the first-stage frequency converter 108 and the second-stage frequency converters 111 and 112 is provided outside the high-frequency IC 10 and has two stages. The frequency converters 111 and 112 of the eye form a quadrature down-conversion mixer, and the band-pass filter 113 provided in the subsequent stage of the frequency converters 111 and 112 of the second stage has a complex characteristic having frequency characteristics as shown in FIG. It is composed of a filter and is built in the high frequency IC 10.
[0024]
The mirror frequency of the second-stage frequency conversion unit is ideally attenuated sufficiently by the quadrature down-conversion mixer and the complex filter, as shown in FIG. 3, so that the second local oscillation frequency signal S104 (frequency f_LO2) Of the second harmonic signal S11 (frequency f)_IF2The band pass filter 3 outside the high frequency IC 10 does not need the steep selection performance as in the prior art, and a low cost band pass filter can be used. 3 (a) shows the input of the second stage frequency converter, (b) shows its output, (c) shows the input of the complex filter, and (d) shows its output.
[0025]
Actually, when the quadrature down-conversion mixer and the complex filter are built in the high-frequency IC 10, the amplitude and phase of the signal are shifted due to mismatch between the circuit that handles the I signal and the circuit that handles the Q signal. S11 (frequency f_IF2) Unnecessary signals are generated in the vicinity. Since the external band-pass filter 3 has a higher selection performance than the band-pass filter configured on the IC, an unnecessary signal down-converted near the second intermediate frequency signal S11 can be further attenuated. The circuit specifications after the frequency converter are relaxed, making it easier to make an IC.
[0026]
  FIG.Is the first2Reference exampleFIG. 2 is a block diagram of the high frequency IC circuit of FIG.Reference exampleWill be explained.
[0027]
  The high frequency IC circuit shown in FIG.Reference example1 is provided with a high frequency IC 20 configured in the same manner as the high frequency IC 10 of FIG. 1 except that a complex filter unit 230 is incorporated instead of the bandpass filter 3 shown in FIG.
[0028]
The complex filter unit 230 is a quadrature generator 231 provided at the output stage of the buffer amplifier 109, and a band interposed between the output of the quadrature generator 231 and the inputs of the second-stage frequency converters 111 and 112. And a pass filter 232.
[0029]
In this configuration, the first intermediate frequency signal S 108 down-converted by the first-stage frequency converter 108 is input to the quadrature generator 231 via the buffer amplifier 109. Then, the quadrature generator 231 outputs the I signal and the Q signal to the second-stage frequency converters 111 and 112 via the band pass filter 232.
[0030]
  FIG.Is the first3Reference exampleFIG. 6 is an operation explanatory diagram of the frequency conversion block of FIG. 5, FIG. 7 is a band pass filter externally attached to the high frequency IC in FIG. 5, and a first-stage frequency conversion unit in the high frequency IC Is an explanatory diagram of the input / output signals regardingReference exampleWill be explained. 7A shows the input of the external bandpass filter, FIG. 7B shows the output thereof, FIG. 7C shows the input of the first stage frequency converter, and FIG. 7D shows the output thereof.
[0031]
  The high frequency IC circuit shown in FIG.Reference example1 is the same as the high-frequency IC 10 of FIG. 1 except that a low-pass filter 330 is incorporated instead of the band-pass filter 3 shown in FIG. 1 and a frequency conversion block 380 is incorporated instead of the frequency converter 108. The high frequency IC 30 is provided.
[0032]
The frequency conversion block 380 receives a quadrature generator 381 that divides the first local oscillation frequency signal S103 from the voltage controlled oscillator 103 into an I signal and a Q signal, and inputs the I signal and the Q signal from the quadrature generator 381. , The signal S2 amplified by the low noise amplifier 101 is frequency f_IF1The quadrature down-conversion mixers 382 and 383 for down-converting the signal to the output signal, a phase shifter 384 for shifting the phase of any one of these outputs (the output of 383 in the figure) by 90 degrees, and via the phase shifter 384 And an adder 385 that adds the two signals obtained from the quadrature down-conversion mixers 382 and 383 to obtain the first intermediate frequency signal S108.
[0033]
The high-frequency IC circuit having the above-described configuration will be further described. The first-stage frequency converter is composed of an image rejection mixer. As shown in FIG. 6, the signal S2 amplified by the low noise amplifier 101 is output by the quadrature down conversion mixers 382 and 383 at a frequency f._IF1Down-converted to At this time, the quadrature down-conversion mixers 382 and 383 receive the I signal (frequency is f) divided by the quadrature generator 381._LO1-I) And Q signal (frequency is f_LO1-Q) And are entered respectively.
[0034]
Both signals down-converted by the quadrature down-conversion mixers 382 and 383 are phase-shifted by 90 degrees by one of the phase shifters 384 and added together by the adder 385 to obtain a first intermediate frequency signal S108 as a buffer amplifier 109. Is output. Thereby, the mirror frequency is removed. However, FIG. 6 is an operation waveform diagram of an ideal image rejection mixer.
[0035]
Here, FIGS. 7A and 7B show the functions performed by the external band-pass filter 2. The characteristic required of the bandpass filter 2 is to suppress the mirror frequency generated in the first-stage frequency converter, and ideally, the function can be achieved by an image rejection mixer. For this reason, the frequency selection characteristics required for the external band-pass filter 2 are greatly relaxed.
[0036]
The quadrature down-conversion mixers 382 and 383 are input by dividing the signal S2 amplified by the low noise amplifier 101 into an I signal and a Q signal, and using the signal output from the voltage controlled oscillator 103 as the first local oscillation frequency signal. However, the effect does not change.
[0037]
In the third embodiment, the high-frequency IC 30 is configured to include the low-pass filter 330 instead of the band-pass filter 3 illustrated in FIG. 1. However, the configuration is not limited thereto, and the high-frequency IC 30 is similar to the high-frequency IC 30 a illustrated in FIG. In addition, the band pass filter 3 may be externally attached, or the high frequency IC 30b shown in FIG. 9 may be replaced with the complex filter unit 230 shown in FIG. 4 instead of the low pass filter 330.
[0038]
Here, the characteristic required for the filter between the first-stage frequency converter and the second-stage frequency converter is to suppress the mirror frequency of the second-stage frequency converter. 5 only needs to attenuate the signal that is down-converted to the second intermediate frequency signal S11 by the third harmonic of the second local oscillation frequency signal S104 used in the second-stage frequency conversion unit. As described above, this can be realized by incorporating a low-order low-pass filter in the high-frequency IC. In this case, the quadrature down-conversion mixer of the second-stage frequency converters 111 and 112 and the complex filter of the bandpass filter 113 need to be matched with high accuracy.
[0039]
On the other hand, as shown in FIGS. 8 and 9, the filter between the first-stage frequency converter and the second-stage frequency converter is connected to the external bandpass filter 3 or the built-in complex If implemented with a band-pass filter, the specifications of the quadrature down-conversion mixer and the complex filter are relaxed, making it easier to implement an IC.
[0040]
  FIG. 10 is a diagram according to the present invention.11 is a configuration diagram of a high-frequency IC circuit according to an embodiment.1An embodiment will be described.
[0041]
  The high frequency IC circuit shown in FIG.Reference example1 is different from FIG. 1 in that a frequency conversion block 480, buffer amplifiers 109a and 109b, and a band pass filter 430 are incorporated instead of the frequency conversion unit 108, the buffer amplifier 109, and the band pass filter 3 in FIG. 1 includes a high frequency IC 40 configured in the same manner as the one high frequency IC 10.
[0042]
The frequency conversion block 480 receives a signal from the low noise amplifier 101 and outputs a quadrature generator 481 that is divided into an I signal and a Q signal, a band pass filter 482 connected to the output, and a voltage controlled oscillator 103. The quadrature generator 483 that divides the first local oscillation frequency signal S103 into an I signal and a Q signal, and the I signal and the Q signal from the quadrature generator 483 are input, and the signal from the band pass filter 482 is converted into a frequency. f_IF1The mixers 484, 485, 487, and 488 that obtain four signals by down-converting the signal to the first signal (first intermediate frequency signal), and adders 486 and 489 that add the four signals from these mixers to the prelude Has been. The outputs of the adders 486 and 489 are connected to the complex filter unit 110 after passing through the buffer amplifiers 109a and 109b and further through the bandpass filter 430, respectively.
[0043]
That is, an image rejection mixer (for example, a double quadrature type) is used as the first stage frequency conversion unit, and a complex bandpass filter unit (quadrulet generator generator 481, band incorporated in the high frequency IC is installed in the preceding stage. A pass filter 482) is arranged.
[0044]
In this configuration, a GPS signal received by the GPS antenna 1 is input to the high frequency IC 40 and amplified by the low noise amplifier 101. The amplified GPS signal is divided into an I signal and a Q signal by a quadrature generator 481 and input to a bandpass filter (complex bandpass filter) 482. The I and Q signals output from the bandpass filter 482 are mixed with the frequency f by the mixers 484, 485, 487, and 488 using the I and Q signals from the quadrature generator 383 as local oscillation frequency signals._IF1Down-converted to Then, the four signals obtained are added to the adders 486 and 489 and the mirror frequency is removed.
[0045]
Thus, the frequency is f by the bandpass filter 482._Lo1Of the first local oscillation frequency signal S103, and the frequency is f_IF1Such as a signal that is down-converted to a first intermediate frequency signal of f_IF1By suppressing unnecessary signals that are down-converted in the vicinity, an external band-pass filter 2 disposed between the GPS antenna 1 and the high-frequency IC 40, which has been conventionally required, becomes unnecessary.
[0046]
  FIG. 11 shows the first aspect of the present invention.21 is a configuration diagram of a high-frequency IC circuit according to an embodiment.2An embodiment will be described.
[0047]
  The high frequency IC circuit shown in FIG.Reference example1 is the same as the high frequency IC 10 of FIG. 1 except that a frequency conversion block 580 and a single mixer unit 510 are incorporated instead of the frequency conversion unit 108 and the complex filter unit 110 in FIG. A high frequency IC 50 is provided.
[0048]
The frequency conversion block 580 receives a signal from the low-noise amplifier 101 and outputs a quadrature generator 481 that is divided into an I signal and a Q signal, a band-pass filter 482 connected to the output, and a voltage-controlled oscillator 103. The first local oscillation frequency signal S103 is input, and the signal from the bandpass filter 482 is input to the frequency f._IF1Are obtained from the mixers 583 and 584 via the phase shifter 585, the phase shifter 585 for shifting the phase of any one of these outputs (the output of 584 in the figure) by 90 degrees, and the phase shifter 585. An adder 586 that obtains a first intermediate frequency signal by adding both signals together. The output of the adder 586 is connected to the input of the buffer amplifier 109.
[0049]
The single mixer unit 510 is connected to a single mixer 511 connected to the output of the bandpass filter 3, a bandpass filter 512 connected to this output, a buffer amplifier 513 connected to this output, and this output. An A / D conversion unit 514 is included.
[0050]
That is, the frequency converter in the first stage is formed by an image rejecting mixer (583, 584, 585, 586), as in the configuration of FIG. 5, and a complex bandpass filter unit built in the high frequency IC 50 is provided in the preceding stage. (481, 482) are arranged. Only the I signal or the Q signal is output from the first-stage frequency conversion unit, and is input to the single mixer 511 as the second-stage frequency conversion unit via the buffer amplifier 109 and the bandpass filter 3. With this configuration, the bandpass filter 2 externally attached before the first-stage frequency conversion unit is not required, and the internal configuration of the high frequency IC 50 can be simplified.
[0051]
  The first2In the embodiment, as shown in the example of FIG. 11, the filter provided between the first-stage frequency converter and the second-stage frequency converter is the external band-pass filter 3. As described in the above embodiments, the filter is not limited to an external band pass filter, and may be a built-in filter.
[0052]
Further, instead of the complex filter unit 110 in each of the above embodiments, for example, a configuration using a real bandpass filter unit 610 shown in FIG. 12 may be used. The real bandpass filter unit 610 includes a pair of real bandpass filters 613a and 613b having frequency characteristics shown in FIG. 13 instead of the bandpass filter 113 of the complex filter unit 110, and an A / D conversion unit 116. , 117 is configured in the same manner as the complex filter unit 110 except that it includes a digital signal processor (DSP) 618 for removing negative frequencies. The real band pass filter unit 610 is built in the high frequency IC in the same manner as the complex filter unit 110. The outputs of the real band pass filters 613a and 613b are input to the A / D converters 116 and 117 via the buffer amplifiers 114 and 115, respectively, and after A / D conversion, the negative frequency is removed by the digital signal processor 618. The Here, the negative frequency is a component that appears in a negative region when a trigonometric function is expressed by a complex function.
[0053]
Alternatively, instead of the complex filter unit 110, for example, a configuration using a real low-pass filter unit 710 illustrated in FIG. The real low-pass filter unit 710 includes a pair of real low-pass filters 713a and 713b instead of the band-pass filter 113 of the complex filter unit 110, and outputs negative frequencies and DC to the outputs of the A / D conversion units 116 and 117. The configuration is the same as that of the complex filter unit 110 except that a digital signal processor 718 for removing the signal is provided. The outputs of the real low-pass filters 713a and 713b are input to the A / D converters 116 and 117 via the buffer amplifiers 114 and 115, respectively, and after A / D conversion, the digital signal processor 718 outputs a negative frequency and DC (0 ) The vicinity is removed.
[0054]
【The invention's effect】
  The invention according to claim 1 is a circuit of an IC for high-frequency reception having a first-stage frequency converter and a second-stage frequency converter,Since the first-stage frequency converter forms an image rejection mixer and the second-stage frequency converter forms a quadrature down-conversion mixer, the image rejection mixer uses the image conversion mixer in the first-stage frequency conversion section. It is possible to suppress the down-conversion of the frequency to the vicinity of the first intermediate frequency signal and to relax the specifications of the external band-pass filter necessary for realizing the same communication performance. Alternatively, no bandpass filter is required. In other words, it is not necessary to use some of the filters placed before and after the two frequency converters as external components, so they can be built into the IC and easily integrated into an IC. Light weight and ease of assembly can be realized, and there is an effect that mixing and radiation of unnecessary signals can be suppressed. In addition, since the complex filter provided before the first-stage frequency conversion unit is built in the IC, a band-pass filter outside the IC provided before the first-stage frequency conversion unit can be eliminated.
[0060]
  Claim2The described invention is a circuit of a high-frequency receiving IC having a first-stage frequency converter and a second-stage frequency converter, and the first-stage frequency converter forms an image rejection mixer, A complex filter provided before the first stage frequency converter is built in the IC, and only the in-phase component I signal or quadrature component Q signal is output from the first stage frequency converter to convert the second stage frequency. Since the unit has a single mixer configuration, an external filter provided before the first-stage frequency conversion unit is not required, and the configuration of the internal circuit of the IC can be simplified. That is, in addition to being easily integrated into an IC, there are effects that the number of parts can be reduced, miniaturization, weight reduction, and easy assembly can be realized, and unwanted signal mixing and radiation can be suppressed.
[Brief description of the drawings]
FIG. 1 shows the present invention.RelatingFirstReference exampleIt is a block diagram of a high frequency IC circuit.
FIG. 2 is a frequency characteristic diagram of a complex filter provided in the high frequency IC of FIG.
3 is an explanatory diagram of input / output signals of a second-stage frequency conversion unit and complex filter in FIG. 1. FIG.
FIG. 4 shows the present invention.RelatingSecondReference exampleIt is a block diagram of a high frequency IC circuit.
FIG. 5 shows the present invention.RelatingThirdReference exampleIt is a block diagram of a high frequency IC circuit.
6 is an operation explanatory diagram of the frequency conversion block of FIG. 5;
7 is an explanatory diagram of input / output signals related to a band pass filter externally attached to the high frequency IC in FIG. 5 and a first-stage frequency conversion unit in the high frequency IC. FIG.
8 is a diagram illustrating another configuration example when the frequency conversion block of FIG. 5 is used.
FIG. 9 is a diagram illustrating another configuration example when the frequency conversion block of FIG. 5 is used.
FIG. 10 is a diagram according to the present invention1It is a block diagram of the high frequency IC circuit of embodiment.
FIG. 11 is a diagram according to the present invention1It is a block diagram of the high frequency IC circuit of embodiment.
FIG. 12 is a diagram illustrating a configuration example when a real bandpass filter unit is used instead of the complex filter unit;
13 is a frequency characteristic diagram of the real bandpass filter of FIG.
FIG. 14 is a diagram illustrating a configuration example when a real low-pass filter unit is used instead of the complex filter unit;
[Explanation of symbols]
  1 GPS antenna
  2 Bandpass filter
  3 Bandpass filter
  10, 20, 30, 30a, 30b, 40, 50 High frequency IC
  101 Low noise amplifier
  102 crystal oscillator
  103 Voltage controlled oscillator
  104 divider
  105 divider
  106 Phase comparator
  107 Low-pass filter
  108 Frequency converter
  109, 109a, 109b Buffer amplifier
  110 Complex filter section
  510 Single mixer section
  610 Real Band Pass Filter
  710 Real low-pass filter
  111, 112 Frequency converter
  113 Band pass filter
  114,115 Buffer amplifier
  116,117 A / D converter
  230 Complex filter section 230
  330 Low-pass filter
  430 Bandpass filter
  380, 480, 580 Frequency conversion block

Claims (2)

An IC circuit for high-frequency reception having a first-stage frequency converter and a second-stage frequency converter, wherein the first-stage frequency converter forms an image rejection mixer, and the second-stage frequency The conversion unit forms a quadrature down-conversion mixer, and a high frequency IC circuit in which a complex filter provided before the first-stage frequency conversion unit is built in the IC. 1. A high-frequency receiving IC circuit having a first-stage frequency converter and a second-stage frequency converter, wherein the first-stage frequency converter forms an image rejection mixer, A complex filter provided before the conversion unit is built in the IC, and only the in-phase component I signal or the quadrature component Q signal is output from the first-stage frequency conversion unit, and the second-stage frequency conversion unit is a single mixer. High frequency IC circuit to be configured .

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