Frequency modulation circuit, FM-CW radar, and high-speed modulation radar
First Claim
Patent Images
1. A frequency modulation circuit comprising:
- a digital-analog converter to output modulation control time-dependent voltage data;
a voltage control oscillator to oscillate, based on the modulation control time-dependent voltage data output from the digital-analog converter, an oscillation frequency signal;
a frequency divider to perform frequency division of the oscillation frequency signal of the voltage control oscillator and output a frequency division signal;
a frequency converter to down-convert the frequency division signal output from the frequency divider;
a single-phase differential converter to convert an intermediate frequency signal of single-phase output from the frequency converter into differential signals and output the differential signals;
an analog-digital converter to convert, concerning the differential signals output from the single-phase differential converter, analog signals of the differential signals into digital signals; and
a signal processing circuit to perform frequency measurement based on the differential signals of the analog-digital converter, update the modulation control time-dependent voltage data based on the measured frequency, and correct a time error of the oscillation frequency signal of the voltage control oscillator.
1 Assignment
0 Petitions
Accused Products
Abstract
A frequency modulation circuit includes a VCO, a DIV, a MIX, a single-phase differential converter, and a signal processing circuit. The signal processing circuit performs differential arithmetic processing of an intermediate frequency signal with a program of a microcomputer according to a quadrature demodulation scheme and, thereafter, measures a frequency from phase information, performs n-th order polynomial (n is an integer equal to or larger than 2) approximation on time-frequency data of an IF signal output by a chirp modulation control voltage after inverse function correction, and performs modulation correction for correcting a time error.
-
Citations
30 Claims
-
1. A frequency modulation circuit comprising:
-
a digital-analog converter to output modulation control time-dependent voltage data; a voltage control oscillator to oscillate, based on the modulation control time-dependent voltage data output from the digital-analog converter, an oscillation frequency signal; a frequency divider to perform frequency division of the oscillation frequency signal of the voltage control oscillator and output a frequency division signal; a frequency converter to down-convert the frequency division signal output from the frequency divider; a single-phase differential converter to convert an intermediate frequency signal of single-phase output from the frequency converter into differential signals and output the differential signals; an analog-digital converter to convert, concerning the differential signals output from the single-phase differential converter, analog signals of the differential signals into digital signals; and a signal processing circuit to perform frequency measurement based on the differential signals of the analog-digital converter, update the modulation control time-dependent voltage data based on the measured frequency, and correct a time error of the oscillation frequency signal of the voltage control oscillator. - View Dependent Claims (2, 3, 4, 5)
-
-
6. A frequency modulation circuit comprising:
-
a digital-analog converter to output modulation control time-dependent voltage data; a voltage control oscillator to oscillate, based on the modulation control time-dependent voltage data output from the digital-analog converter, an oscillation frequency signal; a frequency divider to perform frequency division of the oscillation frequency signal of the voltage control oscillator and output a frequency division signal; a single-phase differential converter to convert the frequency division signal of single-phase output from the frequency divider into differential signals and output the differential signals; an analog-digital converter to convert, concerning the differential signals output from the single-phase differential converter, analog signals of the differential signals into digital signals; and a signal processing circuit to perform frequency measurement based on the differential signals of the analog-digital converter, update the modulation control time-dependent voltage data based on a measured frequency, and correct a time error of the oscillation frequency signal of the voltage control oscillator. - View Dependent Claims (7, 8, 9, 10)
-
-
11. A frequency modulation circuit comprising:
-
a digital-analog converter to output modulation control time-dependent voltage data; a voltage control oscillator to oscillate, based on the modulation control time-dependent voltage data output from the digital-analog converter, an oscillation frequency signal; a frequency divider to perform frequency division of the oscillation frequency signal of the voltage control oscillator and output a frequency division signal; a frequency converter to down-convert the frequency division signal output from the frequency divider and convert an intermediate frequency signal of single-phase into differential signals and output the differential signals; an analog-digital converter to convert, concerning the differential signals output from the frequency converter, analog signals of the differential signals into digital signals; and a signal processing circuit to perform frequency measurement based on the differential signals of the analog-digital converter, update the modulation control time-dependent voltage data based on the measured frequency, and correct a time error of the oscillation frequency signal of the voltage control oscillator. - View Dependent Claims (12, 13, 14, 15)
-
-
16. A frequency modulation circuit comprising:
-
a digital-analog converter to output modulation control time-dependent voltage data; a voltage control oscillator to oscillate, based on the modulation control time-dependent voltage data output from the digital-analog converter, an oscillation frequency signal; a frequency divider to perform frequency division of the oscillation frequency signal of the voltage control oscillator and output a frequency division signal; a balance-unbalance converter to convert the frequency division signal output from the frequency divider into differential signals and output the differential signals; an analog-digital converter to convert, concerning the differential signals output from the balance-unbalance converter, analog signals of the differential signals into digital signals; and a signal processing circuit to perform frequency measurement based on the differential signals of the analog-digital converter, update the modulation control time-dependent voltage data based on the measured frequency, and correct a time error of the oscillation frequency signal of the voltage control oscillator. - View Dependent Claims (17, 18, 19, 20)
-
-
21. A frequency modulation circuit comprising:
-
a digital-analog converter to output modulation control time-dependent voltage data; a voltage control oscillator to oscillate, based on the modulation control time-dependent voltage data output from the digital-analog converter, an oscillation frequency signal; a frequency divider to perform frequency division of the oscillation frequency signal of the voltage control oscillator and convert the frequency division signal into differential signals and output the differential signals; an analog-digital converter to convert, concerning the differential signals output from the frequency divider, analog signals of the differential signals into digital signals; and a signal processing circuit to perform frequency measurement based on the differential signals of the analog-digital converter, update the modulation control time-dependent voltage data based on the measured frequency, and correct a time error of the oscillation frequency signal of the voltage control oscillator. - View Dependent Claims (22, 23, 24, 25)
-
-
26. A frequency modulation circuit comprising:
-
a digital-analog converter to output modulation control time-dependent voltage data; a voltage control oscillator to oscillate, based on the modulation control time-dependent voltage data output from the digital-analog converter, an oscillation frequency signal; a frequency divider to perform frequency division of the oscillation frequency signal of the voltage control oscillator and output a frequency division signal; a frequency converter to down-convert the frequency division signal output from the frequency divider and convert the frequency division signal into an intermediate frequency signal; a balance-unbalance converter to convert the intermediate frequency signal of a single phase output from the frequency converter into differential signals and output the differential signals; an analog-digital converter to convert, concerning the differential signals output from the balance-unbalance converter, analog signals of the differential signals into digital signals; and a signal processing circuit to perform frequency measurement based on the respective differential signals of the analog-digital converter, update the modulation control time-dependent voltage data based on the measured frequency, and correct a time error of the oscillation frequency signal of the voltage control oscillator. - View Dependent Claims (27, 28, 29, 30)
-
Specification