METHOD FOR DETERMINING CALIBRATION FOR MEASURING TRANSIT TIME

Abstract

The invention relates to calibrating a device or a system for signal-transit-time measurement or signal-transit-time-measurement-based distance measurement on the basis of at least one phase measurement. A method for calibrating at least one system for carrying out a signal-transit-time measurement where the system is designed, in cooperation with a first object, to carry out a distance measurement on the basis of a phase measurement, at least one first distance measurement to the first object being carried out by means of phase measurement, particularly by phase shifting and/or modifying a phase shift by the frequency, and at least one signal-transit-time measurement or a second distance measurement carried out on the basis of at least one signal-transit-time measurement to or via the first object. The system is calibrated on the basis of at least one signal-transit-time measurement by means of the at least one first phase measurement.

Claims

1. A method for calibrating at least one system for carrying out one or both of a signal time-of-flight measurement and a signal time-of-flight difference measurement, wherein the system is configured in cooperation with a first object, to carry out a distance measurement on the basis of a phase measurement, wherein at least one first distance measurement to the first object is carried out by means of the phase measurement, and at least one signal time-of-flight measurement or a second distance measurement is carried out on the basis of at least one signal time-of-flight measurement to or via the first object, wherein the system for carrying out further signal time-of-flight measurements or distance measurements or position-finding is calibrated by means of the at least one first phase measurement on the basis of at least one signal time-of-flight measurement, or signal time-of-flight difference measurement.

2. The method according to claim 1, wherein the system contains at least one second object and the distance or time-of-flight measurements are made between the first object and the at least one second object, or the performance of additional signal time-of-flight measurements or distance measurements or position-finding is calibrated by means of the at least one first phase measurement on the basis of at least one signal time-of-flight measurement or signal time-of-flight difference measurement.

3. The method according to claim 1 for calibrating at least one system for carrying out a plurality of signal time-of-flight difference measurements, in each case between a shared first object and a second object of a plurality of second objects, wherein the system is configured for carrying out the at least one first distance measurement between the first object and at least one reference object of the plurality of second objects, on the basis of the phase measurement, wherein the at least one first distance measurement to the first object is carried out by means of the phase measurement, and at least one plurality of signal time-of-flight difference measurements between signal times-of-flight, in each case between the shared first object and the second object from the plurality of second objects, also including the reference object, wherein the system for carrying out further signal time-of-flight difference measurements between signal times-of-flight or distance measurements or position-findings is calibrated by means of the at least one phase measurement, based on further signal time-of-flight difference measurements between signal times-of-flight, in each case between the shared first object and the second object from the plurality of second objects.

4. A use of at least one phase measurement on at least one signal between a first object and at least one second object for calibrating at least one apparatus or system for signal time-of-flight measurement or signal time-of-flight difference measurements or signal time-of-flight-based- or signal time-of-flight-difference-based distance measurement or position-finding of the first object or of at least one second object.

5. The use according to claim 4, wherein the at least one apparatus is part of a system for signal time-of-flight difference measurement-based distance measurement or position-finding of the first object and comprises a plurality of second objects, wherein the system is configured for carrying out a plurality of signal time-of-flight difference measurements between, in each case, the shared first object and a second object from the plurality of second objects, and to determine at least one distance or position of the first object on the basis thereof.

6. The method according to claim 1, wherein the calibration is a calibration of one or both of the signal time-of-flight measurement and signal time-of-flight-based distance measurement between the first object and the second object.

7. The method according to claim 1, wherein the calibration is used for carrying out a plurality of signal time-of-flight measurement(s) or signal time-of-flight-based distance measurement(s), distance measurements or position-findings, of the system, such that the calibration ascertains an offset that is dependent on frequency or temperature, said offset being used as a correction in the at least one signal time-of-flight measurement or signal time-of-flight-based distance measurement.

8. The method according to claim 1, wherein the phase measurement or phase-based distance measurement is not apparatus-specific/system-specific, or is or will be calibrated model range-specifically or series-specifically.

9. The method according to claim 1, wherein multiple phase measurements or phase-based distance measurements at difference frequencies, or multiple measurements of changes in the phase shifts with the frequency at different frequency spacings, are performed before the calibration and used for the calibration, for reducing or excluding ambiguities.

10. The method according to claim 1, wherein a frequency- or temperature-dependent difference, between distance determined in a phase-based manner and signal time-of-flight-based distance measurement is ascertained as a frequency-dependent or temperature-dependent, respectively, correction term by means of which one additional signal time-of-flight measurement or additional distance measurements are corrected on the basis of at least one additional signal time-of-flight measurement of the system.

11. The method according to claim 1, wherein the at least one signal of the signal time-of-flight measurement or the signal on which the phase measurement is performed is a radio signal which contains a shared radio signal, and wherein the signal time-of-flight is the signal time-of-flight for a path between the second object and the first object, or is the signal round-trip time-of-flight between the second object and the first object and back.

12. The method according to claim 1, wherein time spacing between the transmission of the at least one signal for the signal time-of-flight measurement and the at least one signal for the phase measurement is less than 500 ms or wherein the signal time-of-flight measurement and at least one phase measurement are performed on same signal or on signals with similar frequency.

13. The method according to claim 1, is performed individually in each case for a plurality of apparatuses or pairs of same-model apparatuses or apparatuses from a model range or series, wherein only a uniform calibration that is identical for all is used for the phase measurement or phase-based distance measurement for all apparatuses or pairs of the plurality, respectively.

14. An apparatus having a transmission and receiving arrangement as well as a unit for phase measurement, an oscillator, a time measurer, configured for carrying out a signal time-of-flight measurement, having a control for carrying out the method according to claim 1 by means of the apparatus.

15. A system comprising at least two objects, having in each case a transmission or receiving arrangement or both, a PLL or oscillator or both, and a time measurer, and configured together for carrying out a signal time-of-flight measurement between the two objects and a phase-based distance measurement between the two objects, having at least one control for carrying out the method according to claim 1 by means of the at least two objects.

16. The method according to claim 1, wherein the at least one first distance measurement to the first object is carried out by means of phase measurement by means of one or both of a phase shift and a change of a phase shift with the frequency.

17. The method according to claim 3, wherein the system is configured for carrying out a plurality of time-of-flight difference measurements between, in each case, the shared first object and a second object from a plurality of second objects, and to determine a distance or position of the first object on the basis thereof.

18. The method according to claim 1, wherein the calibration of the correction term is frequency-dependent or temperature-dependent, or frequency and temperature dependent.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0061] FIG. 1 shows a schematic depiction of the amplitude over the absolute time.

[0062] FIG. 2 shows a schematic depiction of the change in phase shift due to a frequency change.

[0063] FIG. 3 shows a schematic depiction of the influence of the phase jump when switching.

DETAILED DESCRIPTION

[0064] At the top, FIG. 1 shows a depiction of the amplitude over the absolute time, purely schematically and not limiting. On the left can be seen a signal at the transmitter, the second object, in the form of the amplitude modulation, highly simplified here between zero and a value. Farther to the right, i.e., later in time, the received signal is shown at the receiver, the first object. The signal time-of-flight is illustrated by an arrow.

[0065] At the bottom, FIG. 1 shows a depiction of the amplitude over the absolute time, purely schematically and not limiting. A signal with frequency modulation is shown that can also be used for signal time-of-flight measurement.

[0066] FIG. 2 shows, purely as an example and schematically, an illustration of the change in phase shift due to a frequency change. In the upper depiction, a wave at a lower frequency (above) and a wave at a lower frequency (therebelow) is shown between two objects, respectively marked by a vertical line with a spacing marked by a double-ended arrow. It is evident that the phase change from the transmitter to the receiver ends up being different at the frequencies. In the lower image, the lower wave is shown phase-shifted in order to also emphasize the change in the received phase based on the transmitted phase.

[0067] Purely schematically, FIG. 3 emphasizes the influence of the phase jump when switching. In FIG. 3, an object is respectively shown on the right and left as vertical lines and between them, their spacing is illustrated by a double-ended arrow. A phase-coherent frequency switch is illustrated above in FIG. 3, and a switch with phase jump is illustrated below in FIG. 3. It is evident that the phase jump has an effect on the change in phase difference between the phase at the first and at the second object when switching frequencies. This can be mathematically corrected, however, if the phase jump is known.