Claims
- 1. A waveform display apparatus of frequency sweep type, comprising:
- a measurement unit for measuring a signal to be measured by sweeping a frequency under a predetermined measurement frequency condition so as to obtain waveform data corresponding to the frequency;
- a display device for displaying the waveform data obtained by said measurement unit as developed on a frequency axis thereof;
- first parameter setting means for setting parameters including a measurement frequency range along the frequency axis on said display device;
- reference parameter setting means for setting an arbitrary display position on said display device in the measurement frequency range set by said first parameter setting means as a reference position;
- feature point detection means for detecting a frequency at a feature point of the waveform data measured by said measurement unit in accordance with the parameters set by said first parameter setting means; and
- control means, including a frequency deviation calculation unit for detecting a frequency difference between the frequency at the feature point detected by said feature point detection means, and a frequency corresponding to the reference position, for changing the parameters set by said first parameter setting means in accordance with the frequency difference so as to control the measurement frequency range in said measurement unit, so that the frequency corresponding to the reference position is equal to the frequency at the feature point.
- 2. A waveform display apparatus according to claim 1, wherein said feature point detection means includes means for detecting the frequency of the feature point of the waveform data in each measurement, and said control means includes means for controlling the measurement frequency range so that the frequency corresponding to the reference position is equal to the frequency at the feature point every time a measurement in the measurement frequency range in said measurement unit is performed.
- 3. A waveform display apparatus according to claim 1, wherein said reference parameter setting means includes means for setting a condition representing a zone on the frequency axis on said display device, and sets a predetermined position in the zone as the reference position.
- 4. A waveform display apparatus according to claim 3, wherein said reference parameter setting means includes means for setting a condition representing a zone on the frequency axis on said display device, and sets a predetermined position in the zone as the reference position, and said feature point detection means includes means for detecting the frequency at the feature point of the waveform data in the zone.
Priority Claims (5)
Number |
Date |
Country |
Kind |
2-86973 |
Mar 1990 |
JPX |
|
2-140782 |
Mar 1990 |
JPX |
|
2-189754 |
Jul 1990 |
JPX |
|
2-337347 |
Nov 1990 |
JPX |
|
PCT/JP91/00425 |
Mar 1991 |
WOX |
|
Parent Case Info
This is a division of application Ser. No. 07/776,259 filed Nov. 27, 1991, now U.S. Pat No. 5,434,954.
US Referenced Citations (7)
Foreign Referenced Citations (6)
Number |
Date |
Country |
0283804 |
Sep 1988 |
EPX |
59-145970 |
Aug 1984 |
JPX |
60-203862 |
Oct 1985 |
JPX |
61-288164 |
Dec 1986 |
JPX |
63-75573 |
Apr 1988 |
JPX |
2-231567 |
Sep 1990 |
JPX |
Divisions (1)
|
Number |
Date |
Country |
Parent |
776259 |
Nov 1991 |
|