Rangefinder

Claim 2

Apparatus for distance measurement, wherein a signal source (SQ) is present for generating a frequency-modulated signal, wherein a transmission/reception stage (SES) and a first mixer (MI1) are present, wherein this first mixer is arranged such that it can mixer a signal coming from the transmission/reception stage with the signal generated by the signal source, wherein a reference unit (REF) is present that comprises a surface wave element (OFW) and a second mixer (MI2) and that is provided for delaying the signal coming from the signal source in terms of time and mixing it with the undelayed signal, wherein an evaluation unit (AE) is present that is arranged such that the signals formed by the mixers are supplied to it, and wherein this evaluation unit is configured for a) determining the frequency characteristic of the signal stemming from the second mixer from said signal dependent on the time for arbitrarily prescribed test subject distances, and b) determining the test subject distance with best coincidence by a comparison of these frequency characteristics to a signal stemming from the first mixer by correlation of evaluation according to the least error square.

Claim 3

Apparatus for distance measurement, wherein a signal source (SQ) is present for generating a frequency-modulated signal, wherein a transmission/reception stage (SES) and a first mixer (MI1) are present, wherein this first mixer is arranged such that it can mixer a signal coming from the transmission/reception stage with the signal generated by the signal source, wherein a reference unit (REF) is present that comprises a surface wave element (OFW) and a second mixer (MI2) and that is provided for delaying the signal coming from the signal source in terms of time and mixing it with the undelayed signal, wherein an evaluation unit (AE) is present that is arranged such that the signals formed by the mixers are supplied to it, and wherein this evaluation unit is configured for a) sampling a signal stemming from the first mixer at points in time of specific phase angles of the signal stemming from the second mixer, b) digitizing the sampled values and storing them together with the points in time of the occurrence of the samples, and c) acquiring a signal that would have derived given a linear frequency modulation, acquiring said signal by reading out the values with constant clock rate.

Claim 4

Apparatus for distance measurement, wherein a signal source (SQ) is present for generating a frequency-modulated signal, wherein a transmission/reception stage (SES) and a first mixer (MI1) are present, wherein this first mixer is arranged such that it can mixer a signal coming from the transmission/reception stage with the signal generated by the signal source, wherein a reference unit (REF) is present that comprises a surface wave element (OFW) and a second mixer (MI2) and that is provided for delaying the signal coming from the signal source in terms of time and mixing it with the undelayed signal, wherein an evaluation unit (AE) is present that is arranged such that the signals formed by the mixers are supplied to it, and wherein this evaluation unit is configured for a) sampling a signal stemming from the first mixer at points in time of specific phase angles of the signal stemming from the second mixer, b) digitizing the sampled values and storing them together with the points in time of the occurrence of the samples, and c) acquiring a signal that would have derived given a linear frequency modulation, acquiring said signal by reading out the values with constant clock rate.

Claim 5

Apparatus for distance measurement, wherein a signal source (SQ) is present for generating a frequency-modulated signal, wherein a transmission/reception stage (SES) and a first mixer (MI1) are present, wherein this first mixer is arranged such that it can mixer a signal coming from the transmission/reception stage with the signal generated by the signal source, wherein a reference unit (REF) is present that comprises a surface wave element (OFW) and a second mixer (MI2) and that is provided for delaying the signal coming from the signal source in terms of time and mixing it with the undelayed signal, wherein an evaluation unit (AE) is present that is arranged such that the signals formed by the mixers are supplied to it, and wherein this evaluation unit is configured for a) acquiring and storing the signals stemming from the mixers with a constant sampling rate, b) calculating points in time with predetermined phase angles of the signal stemming from the second mixer, c) determining the appertaining values of the signal stemming from the first mixer at these points in time, and d) acquiring a signal that would have derived given a linear frequency modulation, acquiring said signal by reading out the values with a constant clock rate.

Claim 6

Apparatus for distance measurement, wherein a signal source (SQ) is present for generating a frequency-modulated signal, wherein a transmission/reception stage (SES) and a first mixer (MI1) are present, wherein this first mixer is arranged such that it can mixer a signal coming from the transmission/reception stage with the signal generated by the signal source, wherein a reference unit (REF) is present that comprises a surface wave element (OFW) and a second mixer (MI2) and that is provided for delaying the signal coming from the signal source in terms of time and mixing it with the undelayed signal, wherein an evaluation unit (AE) is present that is arranged such that the signals formed by the mixers are supplied to it, and wherein this evaluation unit is configured for a) acquiring and storing the signals stemming from the mixers with a constant sampling rate, b) calculating points in time with predetermined phase angles of the signal stemming from the second mixer, c) determining the appertaining values of the signal stemming from the first mixer at these points in time, and d) acquiring a signal that would have derived given a linear frequency modulation, acquiring said signal by reading out the values with a constant clock rate.

Claim 7

Apparatus according to one of the claims 1 through 3, wherein a local oscillator and a further mixer (MIL) are present between the signal source and the transmission/reception stage, wherein the local oscillator generates a signal with a frequency that is higher than the frequency stemming from the signal source, and wherein the further mixer is provided for mixing the signal of the signal source with the signal of the local oscillator.

Claim 8

Method for distance measurement, whereby a frequency-modulated signal is generated, whereby the generated signal is beamed out and a part of the signal reflected by a test subject is received, whereby the received signal is mixed with the generated signal to form a measured signal, whereby the generated signal is mixed with a signal delayed in time relative thereto to form a reference signal, whereby the frequency characteristic of the reference signal is determined dependent on the time for arbitrarily prescribed test subject distances, and whereby these frequency characteristics are compared to a measured signal and the test subject distance of best coincidence is determined by correlation or evaluation according to the least error square.

Claim 9

Method for distance measurement, whereby a frequency-modulated signal is generated, whereby the generated signal is beamed out and a part of the signal reflected by a test subject is received, whereby the received signal is mixed with the generated signal to form a measured signal, whereby the generated signal is mixed with a signal delayed in time relative thereto to form a reference signal, whereby the frequency characteristic of the reference signal is determined dependent on the time for arbitrarily prescribed test subject distances, and whereby these frequency characteristics are compared to a measured signal and the test subject distance of best coincidence is determined by correlation or evaluation according to the least error square.

Claim 10

Method for distance measurement, whereby a frequency-modulated signal is generated, whereby the generated signal is beamed out and a part of the signal reflected by a test subject is received, whereby the received signal is mixed with the generated signal to form a measured signal, whereby the generated signal is mixed with a signal delayed in time relative thereto to form a reference signal, whereby a measured signal is sampled at points in time of specific phase angles of the reference signal, whereby the sampled values are digitized and stored together with the points in time of the occurrence of the samples, and whereby a signal that would have derived given a linear frequency modulation is acquired by readout of the values with a constant clock rate.

Claim 11

Method for distance measurement, whereby a frequency-modulated signal is generated, whereby the generated signal is beamed out and a part of the signal reflected by a test subject is received, whereby the received signal is mixed with the generated signal to form a measured signal, whereby the generated signal is mixed with a signal delayed in time relative thereto to form a reference signal, whereby a measured signal is sampled at points in time of specific phase angles of the reference signal, whereby the sampled values are digitized and stored together with the points in time of the occurrence of the samples, and whereby a signal that would have derived given a linear frequency modulation is acquired by readout of the values with a constant clock rate.

Claim 12

Method for distance measurement, whereby a frequency-modulated signal is generated, whereby the generated signal is beamed out and a part of the signal reflected by a test subject is received, whereby the received signal is mixed with the generated signal to form a measured signal, whereby the generated signal is mixed with a signal delayed in time relative thereto to form a reference signal, whereby the measured signal and the reference signal are acquired with constant sampling rate and stored, whereby points in time with predetermined phase angles of the reference signal are calculated, whereby the appertaining values of the measured signal are determined at these points in time, and whereby a signal that would have derived given a linear frequency modulation is acquired by readout of the values with a constant clock rate.

Claim 13

Method for distance measurement, whereby a frequency-modulated signal is generated, whereby the generated signal is beamed out and a part of the signal reflected by a test subject is received, whereby the received signal is mixed with the generated signal to form a measured signal, whereby the generated signal is mixed with a signal delayed in time relative thereto to form a reference signal, whereby the measured signal and the reference signal are acquired with constant sampling rate and stored, whereby points in time with predetermined phase angles of the reference signal are calculated, whereby the appertaining values of the measured signal are determined at these points in time, and whereby a signal that would have derived given a linear frequency modulation is acquired by readout of the values with a constant clock rate.