DE102017100305B4 - Device and method for measuring an optical, capacitive, inductive transmission path by means of multiple modulation - Google Patents

Abstract

Method for measuring the properties of at least one electromagnetic transmission path and / or an object (O) within at least one electromagnetic transmission path (11, 12, 13, 14) for use during an observation period with the following steps:
- Generating a first clock signal (clk1) with a first clock period (T ₁ ) and a first clock signal (clk1q) complementary thereto;
- Generating a second clock signal (clk2) with a second clock period (T ₂ ) which is shorter than the first clock period (T ₁ ), and a second clock signal (clk2q) complementary thereto;
- Mixing the first clock signal (clk1) and the second clock signal (clk2) with a control signal (S4) to form a compensation pre-signal (S3v);
- Mixing the complementary first clock (clk1q) and the complementary second clock signal (clk2q) with the control signal (S4) to form a transmission signal (S5v);
- Emission of a modulated electromagnetic transmission signal (S5i) by a transmitter (H) in the first transmission path (11), the signal intensity (signal energy) of this modulated electromagnetic transmission signal (S5i) being correlated with the transmission pre-signal (S5v) in such a way that at least components the emitted modulated electromagnetic transmission signal (S5i) are proportional to the transmission preliminary signal (S5v) in an observation period which comprises several pulses of the transmission pre-signal (S5v);
- Sending an electromagnetic modulated compensation signal (S3i) by a compensation transmitter (K) into the third transmission path (13), the signal intensity (signal energy) modulating this Compensation signal (S3i) correlated with the compensation pre-signal (S3v) in such a way that at least components of the emitted electromagnetic modulated compensation signal (S3i) are proportional to the compensation pre-signal (S3v) in an observation period which comprises several pulses of the compensation pre-signal (S3v);
- One or more of the two steps
• Reflection of the modulated electromagnetic transmission signal (S5i) on a first object (O) and / or transmission of the modulated electromagnetic transmission signal (S5i) through a first object (O) and subsequent feeding in of the modulated electromagnetic transmission signal (S5i) as a modified electromagnetic transmission signal (S5s ) into a second transmission path (12), wherein the second transmission path (l2) and / or the first transmission path (l1) can be identical to the first object (O), and / or
• Reflection of the electromagnetic modulated compensation signal (S3i) on a second object (O2) and / or transmission of the electromagnetic modulated compensation signal (S3i) through a second object (O2) and subsequent feed of the electromagnetic modulated compensation signal (S3i) as a modified electromagnetic compensation signal (S3s ) into a fourth transmission path (14), the fourth transmission path (l4) and / or the third transmission path (l3) being able to be identical to the second object (O2) and
• where the first object (O) can also be identical to the second object (O2);
- Exit of the modified electromagnetic transmission signal (S5s) of the transmitter (H) from the second transmission path (12), after passing through the same and receiving the modified electromagnetic transmission signal (S5s) by a receiver (D);
- Exit of the modified electromagnetic compensation signal (S3s) of the compensation transmitter (K) from the fourth transmission path (l4) or third transmission path (l3) after passing through the corresponding transmission path (l3, l4) and receipt of the emerged modified electromagnetic compensation signal (S3s) by the Receiver (D), the reception taking place summing and / or multiplying with the modified electromagnetic transmission signal (S5s) of the transmitter (H), which has emerged from the second transmission link (l2), as reception of an overlay;
- Formation of a receiver output signal (S0) by the receiver (D) as a function of the received superimposition of the modified transmission signal (S5s) that emerged from the second transmission path (l2) and the modulated signal that emerged from the fourth transmission path (l4) or third transmission path (l3) electromagnetic compensation transmission signal (S3s);
- Either:
• Forming a first mixed signal (S6) by mixing the receiver output signal (S0) or a signal derived from the receiver output signal on the one hand with the second clock signal (clk2) on the other hand;
• Forming a mixed signal (S7) by mixing the complementary first clock signal (clk1q) with the first mixed signal (S6); or
• Formation of the mixed signal (S7) by mixing the receiver output signal (S0) or one of the Receiver output signal derived signal on the one hand with the second clock signal (clk2) and with the complementary first clock signal (clklq);
- Filtering of the mixed signal (S7) to form a control pre-signal (S8);
- Analog-to-digital conversion of the pre-control signal (S8) to a digitized control signal (S9) in order to obtain a digital pre-control signal (S9);
- Filtering and / or delaying the digital control signal (S9) to said control signal (S4),
• wherein the filtering and / or delay is synchronized with the first clock signal (clk1) and / or the complementary first clock signal (clklq);
- Output of the control signal (S4) or a signal derived therefrom as a measured value signal for the properties of at least one of the optical transmission links and / or at least one of the objects (O, O2) within at least one of the optical transmission links (l1, l2, l3, l4).

Description

The invention is directed to a method and system using reflection or re-emission of electromagnetic waves. The focus is on the use of optical waves with the transmission of continuous, non-modulated, amplitude, frequency or phase modulated waves. The proposed device is also suitable for systems that use the reflection or re-emission of radio waves or comparable systems that use the reflection or re-emission of waves whose type or wavelength is insignificant or not specified. The device also relates to measures for monitoring, calibration or verification. The device is also suitable as a measuring arrangement, characterized by the use of optical measuring means for measuring distances and general optical properties of objects and transmission channels. It also relates to arrangements for detecting objects by means of ultraviolet, visible and infrared light. LEDs and lasers are particularly suitable as light sources (transmitters). The method is also suitable for electrical or magnetic prospecting or tracing or the measurement of magnetically or electrostatically active objects.

General introduction

Devices and methods for measuring an optical, capacitive, inductive transmission path are used in a wide variety of applications. Examples include: Gesture recognition systems, rain sensors, lane recognition, ice sensors, etc. As a rule, the optical, in particular electromagnetic properties of a transmission link and / or the optical and, in particular, electromagnetic properties of an object within the transmission link can be recognized.

State of the art

• EP 2 016 480 B1 , EP 2 598 908 B1 , WO 2013 113 456 A1 , EP 2 594 023 B1 , EP 2 653 885 A1 ,
• EP 2 418 512 A1 , EP 2 405 283 B1 , EP 1 671 160 B1 , WO 2013 037 465 A1 , EP 1 901 947 B1 ,
• US 2012 0 326 958 A1 , EP 1 747 484 B1 , DE 10 2008 016 938 B3 , EP 1 723 446 B1 ,
• EP 1 435 509 B1 , EP 1410 507 B1 , EP 1 269 629 B1 , EP 1 258 084 B1 ,
• EP 801 726 B1 , EP 1 480 015 A1 , DE 10 2005 045 993 B4 , DE 4 339 574 C2 , DE 4 411 770 A1
• DE 4 411 773 C2 , WO 2013 083 346 A1 , EP 2 679 982 A1 , WO 2013 076 079 A1 ,
• WO 2013 156 557 A1 .

The invention relates to a compensating electromagnetic and / or optical measuring section. Such a measuring principle is known as the HALIOS ^® system, which is known, for example, from the following disclosures:

• EP 2 016 480 B1 , EP 2 598 908 B1 , WO 2013 113 456 A1 , EP 2 594 023 B1 , EP 2 653 885 A1 ,
• EP 2 418 512 A1 , EP 2 405 283 B1 , EP 1 671 160 B1 , WO 2013 037 465 A1 , EP 1 901 947 B1 ,
• US 2012 0 326 958 A1 , EP 1 747 484 B1 , DE 10 2008 016 938 B3 , EP 1 723 446 B1 ,
• EP 1 435 509 B1 , EP 1410 507 B1 , EP 1 269 629 B1 , EP 1 258 084 B1 ,
• EP 801 726 B1 , EP 1 480 015 A1 , DE 10 2005 045 993 B4 , DE 4 339 574 C2 , DE 4 411 770 A1
• DE 4 411 773 C2 , WO 2013 083 346 A1 , EP 2 679 982 A1 , WO 2013 076 079 A1 ,
• WO 2013 156 557 A1 .

• WO 2014 096 385 A1 , DE 10 2014 002 194 A1 , DE 10 2014 002 788 A1 , DE 10 2014 002 486 A1

The following registrations also concern Halios ^® systems:

• WO 2014 096 385 A1 , DE 10 2014 002 194 A1 , DE 10 2014 002 788 A1 , DE 10 2014 002 486 A1

• • ein Sender (H), der von einem Sendesignal (S5) gespeist wird, in eine erste Übertragungsstrecke (l1) ein moduliertes elektromagnetisches Sendesignal (S5i) einspeist, das mit dem Sendesignal (S5) korreliert, und
• • diese erste Übertragungsstrecke (l1) an einem zu vermessenden Objekt (O) endet, das das modulierte elektromagnetische Sendesignal (S5i) des Senders (H) reflektiert und/oder transmittiert und damit modifiziert, und
• • in eine zweite Übertragungsstrecke (12) als modifiziertes elektromagnetisches Sendesignal (S5s) einspeist, und
• • wobei die zweite Übertragungsstrecke (12) an einem Empfänger (D) endet, und
• • dass ein Kompensationssender (K), der durch ein Kompensationssendesignal (S3) gespeist wird, in eine dritte Übertragungsstrecke (13), die ebenfalls an dem Empfänger (D) endet, ein moduliertes Kompensationssignal (S3i) einspeist, das mit dem Kompensationssignal (S3) korreliert, und
• • dass sich das modifizierte elektromagnetische Sendesignal (S5s) und das elektromagnetische Kompensationssignal (S3i) im Empfänger (D) überlagern, wobei aus dem Stand der Technik lineare und multiplizierende Überlagerungen bekannt sind, und
• • dass das so überlagerte Gesamtsignal durch den Empfänger (D) in ein Empfängerausgangssignal (S0) gewandelt wird und
• • dass auf Basis dieses Empfängerausgangssignals (S0) zumindest ein Regler (CT) nun das Sendesignal (S5) und/oder das Kompensationssignal (S3) in der Amplitude so ausregelt, dass zumindest für einen bestimmten Spektralbereich der Modulation des Empfängerausgangssignals (S0) die relevanten Anteile des Modulationsspektrums des Sendesignals (S5) im Empfängerausgangssignal (S0) verschwinden.

What all of these methods have in common is that

• • a transmitter ( H ) from a broadcast signal ( S5 ) is fed into a first transmission link ( l1 ) a modulated electromagnetic transmission signal ( S5i ) that feeds in with the transmit signal ( S5 ) correlated, and
• • this first transmission path ( l1 ) on an object to be measured ( O ) ends that the modulated electromagnetic transmission signal ( S5i ) of the sender ( H ) reflected and / or transmitted and thus modified, and
• • into a second transmission path ( 12th ) as a modified electromagnetic transmission signal ( S5s ) feeds, and
• • where the second transmission path ( 12th ) to a recipient ( D. ) ends, and
• • that a compensation transmitter ( K ), which is triggered by a compensation transmission signal ( S3 ) is fed into a third transmission path ( 13th ), which are also sent to the recipient ( D. ) ends, a modulated compensation signal ( S3i ) that feeds in with the compensation signal ( S3 ) correlated, and
• • that the modified electromagnetic transmission signal ( S5s ) and the electromagnetic compensation signal ( S3i ) in the receiver ( D. ) superimpose, linear and multiplying superimpositions being known from the prior art, and
• • that the overall signal superimposed in this way by the receiver ( D. ) into a receiver output signal ( S0 ) is converted and
• • that on the basis of this receiver output signal ( S0 ) at least one controller ( CT ) now the transmission signal ( S5 ) and / or the compensation signal ( S3 ) regulates the amplitude so that at least for a certain spectral range the modulation of the receiver output signal ( S0 ) the relevant parts of the modulation spectrum of the transmitted signal ( S5 ) in the receiver output signal ( S0 ) disappear.

This control principle is referred to below as the "old HALIOS ^® principle".

1 shows the system of EP 2 602 635 B1 from the state of the art. In the system of EP 2 602 635 B1 it is a variation of the old HALIOS ^® principle, in which the absolute amplitude of the transmitter signal ( H ) and the compensation transmitter ( K ) is not changed. A clock generator ( G ) generates a digital base broadcast signal ( S50 ). This basic broadcast signal ( S50 ) is activated via a first switch ( SW1 ), from the control signal ( S4 ) is controlled, into the send pre-signal ( S5v ) or the compensation signal ( S3v ) converted. The modulation of the compensation transmitter ( K ) with the basic broadcast signal ( S50 ) switched off when the first switch ( SW1 ) assumes a first switch position, which is the basic transmission signal ( S50 ) not with the compensation pre-signal ( S3v ), but the pre-transmit signal ( S5v ) connects. In this first switch position of the first switch ( SW1 ) is the modulation of the transmitter ( H ) turned on. The modulation of the compensation transmitter ( K ) with the basic broadcast signal ( S50 ) is switched on when the first switch ( SW1 ) has a second switch position, which is the basic transmission signal ( S50 ) with the compensation pre-signal ( S3v ) and not with the pre-transmit signal ( S5v ) connects. In this second switch position of the first switch ( SW1 ) is the modulation of the transmitter ( H ) switched off. This switching corresponds to the multiplication of the base transmission signal ( S50 ) with the control signal ( S4 ) to the compensation signal ( S3v ) and with the inverted control signal ( S4 ) to the pre-transmit signal ( S5v ). So it is a good example of realizing a multiplier through a switch.

A second amplifier ( V2 ) generates the transmission signal ( S5 ) from the pre-send signal ( S5v ) and typically supplies the transmitter ( H ) with electrical energy. A third amplifier ( V3 ) generates the compensation signal ( S3 ) from the compensation pre-signal ( S3v ) and typically supplies the compensation transmitter ( K ) with electrical energy. This either causes the sender ( H ) or the compensation transmitter ( K ) with the basic broadcast signal ( S50 ) of the generator ( G ) modulated, whereby the control signal ( S4 ) determines which of these two transmitters ( K , H ) is currently transmitting and is being modulated in the process. The transmitter ( H ) now irradiates, as described above, over a first transmission path ( l1 ) the object ( O ) with the modulated electromagnetic transmission signal ( S5i ). This object ( O ) now reflects and / or transmits the radiated electromagnetic radiation into a second transmission path ( 12th ). It is known from the prior art that both a measurement of the properties of the transmission path ( 11 , 12th ) or parts thereof, as well as a measurement of object properties of the object ( O ) is possible. The compensation transmitter ( K ) radiates into a third transmission path known in most applications ( 13th ) on. Such a device is typically arranged so that the transmitter ( H ) not directly into the recipient ( D. ) can radiate in and the compensation transmitter ( K ) if possible only directly into the recipient ( D. ) can radiate. For an optimal setting of the operating point, the electromagnetic radiation from the compensation transmitter ( K ) in the third transmission path ( 13th ) typically weakened so that the compensation transmitter ( K ) can work in the same electrical and electromagnetic operating point as the transmitter ( H ). The attenuation in the third transmission path ( 13th ) dimensioned in such a way that this weakening is combined with a weakening of the electromagnetic radiation of the transmitter that occurs for the intended application ( H ) in the first and second transmission path ( 11 , 12th ) and by a typical object ( O ) matches. The electromagnetic radiation from the transmitter ( H ) and the compensation transmitter ( K ) are each after passing through their respective transmission links ( 11 , 12th , 13th ) in the receiver ( D. ), as mentioned, received superimposed. This generates a receiver output signal ( S0 ). Through a filter, which is preferably a band pass filter ( BP ), the reception is based on the frequency spectrum of the modulation of the basic transmission signal ( S50 ) limited. This serves, for example, to dampen the influence, for example, of interference levels from solar radiation in optical applications or from other external radiators. This can occur despite the subsequent signal processing due to non-linearities, otherwise without such filtering ( BP ), still lead to errors. The output signal of the filter ( BP ), the filtered receiver output signal ( S1 ), then becomes the amplified receiver output signal ( S2 ) through a first amplifier ( V1 ) reinforced. It is obvious to a person skilled in the art that filters ( BP ) and first amplifier ( V1 ) can be run as a single unit. The amplified receiver output signal is particularly preferred ( S3 ), a differential signal. In a first multiplier ( M1 ) the amplified receiver output signal ( S2 ) with the basic broadcast signal ( S50 ) to the first mixed signal ( S6 ) multiplied and thereby mixed. In the case of a differential, amplified receiver output signal ( S2 ) by interchanging or not interchanging the two lines of the differential, amplified receiver output signal ( S2 ) depending on the logical state of the basic transmission signal ( S50 ) happen. This would then correspond to a multiplication by -1 and 1 in each case. In the following, a multiplication by 0 and 1 is the same described. A sign generator ( VG ) generates a sign signal ( S4i ), which is the sign of the control signal ( S4 ) indicates. With this sign signal ( S4i ) the mixed signal ( S7 ) in a second multiplier ( M2 ) to the demodulated receiver output signal ( S7 ) multiplied. In the case of a differential signal, this can also be done by interchanging the two lines of the differential signal. A first filter ( F1 ) filters the demodulated receiver output signal ( S7 ) to the pilot signal ( S8 ). Typically the first filter is ( F1 ) a simple integrator, a low pass or a band pass that only lets through the frequencies of interest. A comparator or analog-to-digital converter ( ADC ) converts the pilot signal ( S8 ) into the digital pilot signal ( S9 ) around. In a delay stage ( FF ) the digital pilot signal ( S9 ) by one cycle of the basic transmission signal ( S50 ) to the control signal ( S4 ) delayed. The control signal ( S4 ) represents the measured value as a serial delta-sigma data stream.

In this one, in the EP 2 602 635 B1 disclosed device are dependent on the control signal ( S9 ) through the output of the analog-to-digital converter ( ADC ) is formed, the sender ( H ) and the compensation transmitter ( K ) pulsed with constant amplitude. A delta-sigma loop controls the density of the pulses from the compensation transmitter ( K ) and the transmitter ( H ) in such a way that, averaged over time, the same amount of electromagnetic transmission radiation, for example the same amount of light energy, of the two transmission channels of the transmitter ( H ) and the compensation transmitter ( K ) to the recipient ( D. ) meets. At this point it should be mentioned that this is already a simplified representation. In a typical realization of the technical teaching of the EP 2 602 635 B1 is in reality the amount of signal of a signal pulse, for example the amount of light energy of a light pulse, because of the bandpass ( BP ) not linearly proportional to the demodulated electrical pulses of the demodulated receiver output signal of the EP 2 602 635 B1 . In this typical realization of the technical teaching of the EP 2 602 635 B1 a delta-sigma loop then controls the density of the pulses from the compensation transmitter ( K ) and the transmitter ( H ) in such a way that, averaged over time, the area of the demodulated received pulses of the demodulated receiver output signal, i.e. the mixed signal ( S7 ), the two transmission channels, the transmitter ( H ) and the compensation transmitter ( K ), is the same (see 2 ). The demodulated receiver output signal (i.e. the mixed signal S7 ) is described in more detail below. The delta-sigma data stream of the synchronized output (digital control signal S9 ) of the analog-to-digital converter ( ADC ) used. This delta-sigma data stream is typically the output (control signal S4 ) of a flip-flop (delay stage FF ), for delay and synchronization.

During the implementation, the following problems emerged: Since the technical teaching of the EP 2 602 635 B1 only 50% of the time one of the two transmitters, the compensation transmitter ( K ) or the sender ( H ), is switched on, the receiver ( D. ) always the full pulse height of the two transmitters ( H , K ) receive. Therefore, compared to the old HALIOS ^® principle, in which only the difference signal is amplified, the amplification of the received signal is limited. This restricts - as was recognized in the context of the elaboration of the invention - the theoretical measurement resolution of the system.

Another problem is that the bandpass mean value of the bandpass ( BP ) in the analog amplifier path depends on the current pulse ratio of the two transmission channels. This makes it very difficult to temporarily pause the system without interference, which experience has shown that this is regularly the case in applications. If the integrator (first filter F1 ) is stopped, there is no information about which transmitter ( H , K ) should pulsate. The bandpass mean value of the bandpass ( BP ) changes and with it the pulse height to be integrated.

A need to pause arises, for example, if the reference voltage is disturbed by other measurements carried out in parallel by the same integrated circuit, as part of which the device according to the invention may be implemented.

Furthermore, when using LEDs as transmitters ( H ) and compensation transmitter ( K ) occasionally observed in optical systems that the non-constant control of the transmitters (S, K), in particular the non-constant control of transmitter LEDs, according to the disclosure of the patent EP 2 602 635 B1 , can lead to further parasitic effects. Such a parasitic effect is particularly evident in the case of delayed switching on of the LED driver ( V2 , V3 ) not excluded after a long off phase. Thermal effects due to the low pulse rates of a transmitter ( H , K ), especially a transmitter diode, can occur.

The solution described below is based on the state of the art (see 2 , 4th , 6th , 7th , 8th ). In 2 is the technique of DE 10 2015 006 174 B3 shown. In this known method and apparatus of the DE 10 2015 006 174 B3 from the state of the art, the transmitters ( H ) with constant amplitude independent of the digitized control signal ( S9 ) always alternately pulsed, so that there is always one transmitter ( H , K ) is always switched on for 50% of the total time and sends. This creates behind the first amplifier ( V1 ) an alternating signal as an amplified receiver output signal ( S2 ), the amplitude of which is proportional to the difference in the received signal amplitude, in the case of LEDs as transmitters it is proportional to the difference in the amount of light received between the two measuring channels.

The demodulator modulates the DE 10 2015 006 174 B3 not always at the same time, but depending on the output of the analog-to-digital converter ( ADC ), the digital pilot signal ( S9 ), also phase shifted by 180 °. If the digital pilot signal ( S9 ) is logical 1, one transmitter (or one transmitter diode) is demodulated, and if the digital control signal ( S9 ) is logical 0, the other transmitter (or the other transmitter diode) is demodulated.

In addition, the DE 10 2015 006 174 B3 a low reference voltage ( vref2 ) by a reference value transmitter ( LR ) to generate a degraded, inverted signal of the amplifier chain. This reference voltage ( vref2 ) is in the DE 10 2015 006 174 B3 used as an inverted signal for the demodulator. The integrator (filter F1 ) the DE 10 2015 006 174 B3 uses the additional low reference voltage ( vref2 ) as reference potential.

Instead of the signal amplitude (with LEDS as transmitters, the amount of light) via the number (temporal pulse density) of the pulses from the transmitter ( H , K ) is regulated in the DE 10 2015 006 174 B3 the pulse density is regulated via the density of the demodulated electrical pulses of the demodulator. The bit stream (digital control signal S9 ) decides whether the "positive" phase or the 180 ° shifted "negative" phase in the filter ( F1 ) is integrated.

As a measurement signal (control signal S4 ) is the output signal of the in a flip-flop - as a delay stage ( FF ) - to the pre-transmit signal ( S5v ) synchronized output (digitized control signal S9 ) of the analog-to-digital converter ( ADC ) is used, which indicates the measured value via the averaged 0-1 ratio. For example, the control signal ( S4 ) with a digital low-pass filter (not shown) with a break frequency of 170 Hz, for example, and output as an 11-bit value.

This measuring method of the DE 10 2015 006 174 B3 thus measures the difference between the two received pulse heights of the two channels 1 and 2.

Problem Description

When working out the invention, the property right EP 2 602 635 B1 disclosed technical teaching implemented as a measuring method. Difficulties arose when modulated interference radiation was radiated into the transmission channel ( 11 , 12th ) and during EMC radiation tests. Only a sensitivity at the sampling frequency (eg 100Khz) and a multiple of the same was expected. In the context of the elaboration of the invention, however, it was now surprisingly found that a considerable sensitivity from 1/10 of the sampling frequency (here approx. 10 kHz) could be observed at a very large number of frequencies ( 6th , 7th , 8th ). It was more of a frequency band. The frequency sensitivity also depends on the direct signal component (hereinafter also DC value) of the measurement signal. The DC value is the time averaged value of the 0-1 sequences.

In the 6th , 7th and 8th the measured sensitivity for a modulated interference radiation of 10 Hz to 1 MHz is shown. It shows 6th , the frequency response according to an exemplary implementation EP 2 602 635 B1 (DC voltage component). 7th shows the corresponding peak-to-peak value (AC voltage component). 8th shows the corresponding peak-to-peak value with double-logarithmic scaling (in dB). The results suggest that the automotive applications would fail certain tests and problems with systems communicating via IR light (e.g. traffic signs in Asia) or frequency-modulated LED light would exist if IR transmitting diodes were used.

Cause of problem

It has now been recognized that the cause of the problems of the prior art according to FIG EP 2 602 635 B1 the sampling or integration of a potential interference signal ( SR ) is. Although it is sampled at 100 kHz, it is not continuously integrated or integrated in a cyclical manner. Whether it is integrated up or down depends on the last value of the bit data stream, the control signal ( S4 ) from and thus from the measured value. It was recognized that the effective sampling frequency varies continuously and that an interfering signal ( SR ) thus in turn changes the effective sampling frequency. Since an interfering signal ( SR ) is folded into the useful band with the effective sampling frequency and the width of the digital low-pass filter, there is the measurement method of EP 2 602 635 B1 thus a lot of interfering frequencies.

Object of the invention

It is the object of the invention to specify a compensating measuring device that this disadvantage of the technical teaching of EP 2 602 635 B1 avoids. The frequency sensitivity of devices according to the technical teaching of EP 2 602 635 B1 against interference from outside should be eliminated for all interfering frequencies. Only at the sampling frequency of a device according to the invention and the multiple thereof, a sensitivity to interference sources is accepted as unavoidable, provided that these interference frequencies are not filtered away by a bandpass. The aim is to constantly sample or integrate an interfering signal in a cyclical manner.

This object is achieved by a device according to claim 1 or 2 and a method according to claim 3.

Solution of the problem according to the invention

• Statt einer Multiplikation des Sendetaktes in Form des bisherigen Basissendesignals (S50) einerseits mit dem Regelsignal (S4) andererseits wird nun vorgeschlagen, den Sendetakt in Form eines ersten Taktsignals (clk1) mit einem zweiten Taktsignal (clk2) und mit dem Regelsignal (S4) zu mischen und zwar bevorzugt zu multiplizieren.

In the 3 and 5 an improved device is shown. The difference to existing procedures ( EP 2 602 635 B1 ) is as follows:

• Instead of multiplying the transmission clock in the form of the previous base transmission signal ( S50 ) on the one hand with the control signal ( S4 ) on the other hand, it is now proposed to set the send clock in the form of a first clock signal ( clk1 ) with a second clock signal ( clk2 ) and with the control signal ( S4 ) to mix and preferably to multiply.

The definition of the first clock signal ( clk1 ) and the second clock signal ( clk2 ) important. For example, on the one hand it is possible to use the clock signals ( clk1 , clk2 ) to be defined as symmetrical clock signals around the 0 value. On the other hand, it is possible to interpret the first and second clock signals as fluctuating between 0 and a maximum amplitude, for example 1. Depending on such level definition of the signals, the position of the inverting amplifiers or the inverters in the signal path and the use of the original signal or of the signal complementary to the original signal may have to be adapted. Two examples are given below.

Case I: clk1 and clk2 between -1 and +1

First, a first example with a first clock signal ( clk1 ) and a second clock signal ( clk2 ), in which these clock signals ( clk1 , clk2 ) fluctuate between -1 and +1.

The mix on the side of the transmitter ( H ) takes place in this case I with a to the first clock signal ( clk1 ) complementary first clock signal (clklq ), for example by inverting the first clock signal ( clk1 ) can be generated, and with a second clock signal ( clk2 ) complementary second clock signal ( clk2q ), for example by inverting the second clock signal ( clk2 ) can be generated. The mix on the side of the compensation transmitter ( K ) does not take place in the opposite direction with the complementary first clock signal ( clk1q ) and the complementary second clock signal ( clk2q ) on the side of the transmission signal but with the first clock signal ( clk1 ) and the second clock signal ( clk2 ). This causes the sender to send ( H ) whenever the compensation transmitter ( K ) does not send and vice versa. The first period ( T ₁ ) of the first clock signal ( clk1 ) is from the second period ( T ₂ ) of the second clock signal ( clk2 ) different. It is particularly preferred and advantageous if the first period ( T ₁ ) an even multiple of the second period ( T ₂ ) is. In addition to the useful signal at f = 0 Hz, this results in four satellite bands in terms of frequency on the measurement signal that is sent into the first transmission path - two in the negative frequency range and two in the positive frequency range. After reception, a corresponding two-stage demodulation takes place. Is the magnitude of the frequency ( 1 / T ₂ ) of the second clock signal ( clk2 ) an integer multiple, preferably increased by an even factor, of the magnitude of the frequency of the first clock signal ( clk1 ), and is the duty cycle of the second clock signal ( clk2 ) 50%, this additional modulation with the increased clock frequency eliminates considerable parts of the low-frequency interference. In particular, disturbances ( SR ) with a frequency corresponding to the first clock frequency ( 1 / T ₁ ) used for sampling the output of the analog-to-digital converter ( ADC ) for example by means of a flip-flop ( FF ) is used, shifted to a different frequency range by multiplication with the second clock frequency (1 / T ₂ ) and are therefore no longer effective for the scanning.

Case II: clk1 and clk2 between 0 and +1

A second example with a first clock signal ( clk1 ) and a second clock signal ( clk2 ), in which these clock signals ( clk1 , clk2 ) fluctuate between 0 and +1 instead of between -1 and 1.

The problem arises here that when the higher-frequency second clock signal ( clk2 ) with the low-frequency first clock signal ( clk1 ) Pulses of the second clock signal ( clk2 ) by the first clock signal ( clk1 ) are deleted in its 0 phases. The multiplication must therefore take place in a different way for this case than for case I ( 4th ) with levels symmetrical to zero. This case II ( 3 ) is of particular interest for the implementation, since it allows a simple digitization of the method and is therefore to be seen here as the preferred case. This problem will be discussed in more detail below.

The modulation with a first clock signal ( clk1 ) with a first frequency ( 1 / T ₁ ) and a second clock signal ( clk2 ) with a second frequency ( 1 / T ₂ ) with preferred T ₁ = 2 * n * T ₂ is the decisive inventive idea that has not yet been used in any preceding document is known from the prior art.

The invention can be used for case I ( clk1 and clk2 Levels between -1 and 1) with regard to the transmission side are summarized in such a way that the transmission signal ( S5 ) with a band-limited clock signal ( clk1 × ckl2 ) multiplied by the control signal ( S4 ) is modulated. The compensation transmission signal ( S3 ) is used with the corresponding complementary band-limited clock signal ( clk1q × ckl2q ) modulated. The band-limited clock signal ( clk1 × ckl2 ) preferably has a lower limit frequency in terms of absolute value ω _u and an upper limit frequency in terms of magnitude ω _o with an absolute frequency bandwidth Δω = ω _ο -ω _u and an absolute center frequency ω _m = Δω / 2 + ω _u .

The invention can be used for case II ( clk1 and clk2 Levels between 0 and 1), on the other hand, are summarized with regard to the transmission side in such a way that the transmission signal ( S5 ) with a first band-limited clock signal ( clklq × ckl2 ) is modulated, for example by multiplying the complementary first clock signal (clklq ) with the second clock signal ( clk2 ) is generated and at the same time with a complementary control signal ( S4q ) is multiplied. The compensation transmission signal ( S3 ) is used with the corresponding second band-limited clock signal ( clkl × ckl2 ) modulated, for example by multiplying the first clock signal ( clk1 ) with the second clock signal ( clk2 ) is generated and at the same time with a complementary control signal ( S4q ) is multiplied. The first band-limited clock signal ( clk1q × ckl2 ) and the second band-limited clock signal ( clk1 × ckl2 ) preferably have a typically common lower limit frequency in terms of absolute value ω _u and a typically common upper limit frequency in terms of magnitude ω _o with a typically common absolute frequency bandwidth Δω = ω _ο -ω _u and a typically common absolute center frequency ω _m = Δω / 2 + ω _u .

und der zweite normierte Amplitudenverlauf $$N_2\left(\omega \right)=\frac{\left|A_2\left(\omega \right)\right|}{{\displaystyle \underset{{\omega }_a}{\overset{{\omega }_b}{\int }}\left|A_2\left(\omega \right)\right|d\omega }}$$

über den für die Funktionstüchtigkeit des Messsystems relevanten Frequenzbereich (hier von ω_a bis ω_b ) der Frequenz (ω) ineinander derart überführt werden können, dass gilt: $$\left|{\text{N}}_2\left(\mathrm{\omega }\right)-{\text{N}}_1\left(2\ast \mathrm{\omega }\right)\right|\le \left|{\text{N}}_1\left(2\ast \mathrm{\omega }\right)\right|\ast 10\%.$$

The advantageous effect already described above can now be achieved in case I and in case II for any clock signals that their frequency spectra can be converted into one another after amplitude normalization has taken place. The above for mono-frequency clock signals ( clk1 , clk2 ) described conditions can be applied to a first non-mono-frequency clock signal ( clk1 ) and a second non-mono-frequency clock signal ( clk2 ) can now be expanded and generalized, with a complementary first clock signal ( clk1q ) again complementary to the first clock signal ( clk1 ) and where the complementary second clock signal ( clk2q ) again complementary to the second clock signal ( clk2 ) is. The first clock signal ( clk1 ) has a first frequency spectrum ( A ₁ ( ω )) with regard to its amplitude and the complementary second clock signal ( clk2q ) a second frequency spectrum (A ₂ ( ω )) in terms of its amplitude. Analogously, the complementary first clock signal ( clk1q ) a third frequency spectrum (A ₃ ( ω )) the complementary second clock signal ( clk2 ) a fourth frequency spectrum (A ₄ ( ω )) in terms of its amplitude. In order to meet the conditions described above, it is advantageous if the first normalized amplitude curve $$N_1\left(\omega \right)=\frac{\left|{\mathrm{A.}}_1\left(\omega \right)\right|}{{\displaystyle \underset{{\omega }_a}{\overset{{\omega }_b}{\int }}\left|{\mathrm{A.}}_1\left(\omega \right)\right|d\omega }}$$

and the second normalized amplitude curve $$N_2\left(\omega \right)=\frac{\left|{\mathrm{A.}}_2\left(\omega \right)\right|}{{\displaystyle \underset{{\omega }_a}{\overset{{\omega }_b}{\int }}\left|{\mathrm{A.}}_2\left(\omega \right)\right|d\omega }}$$

over the frequency range relevant for the functionality of the measuring system (here from ω _a until ω _b ) the frequency ( ω ) can be converted into one another in such a way that: $$\left|{\text{N}}_2\left(\mathrm{\omega }\right)-{\text{N}}_1\left(2\ast \mathrm{\omega }\right)\right|\le \left|{\text{N}}_1\left(2\ast \mathrm{\omega }\right)\right|\ast 10\%.$$

This condition also applies to the complementary clock signals ( clk1q , clk2q ) or for the complementary bandwidth-limited clock signal (clk1q × clk2q).

und der vierte normierte Amplitudenverlauf $$N_4\left(\omega \right)=\frac{\left|A_4\left(\omega \right)\right|}{{\displaystyle \underset{{\omega }_a}{\overset{{\omega }_b}{\int }}\left|A_4\left(\omega \right)\right|d\omega }}$$

über den für die Funktionstüchtigkeit des Messsystems relevanten Frequenzbereich (hier von ω_a bis ω_b ) der Frequenz (ω) ineinander derart überführt werden können, dass gilt: $$\left|{\text{N}}_4\left(\mathrm{\omega }\right)-{\text{N}}_3\left(2\ast \mathrm{\omega }\right)\right|\le \left|{\text{N}}_3\left(2\ast \mathrm{\omega }\right)\right|\ast 10\%,$$

The third normalized amplitude curve should correspondingly $$N_3\left(\omega \right)=\frac{\left|{\mathrm{A.}}_3\left(\omega \right)\right|}{{\displaystyle \underset{{\omega }_a}{\overset{{\omega }_b}{\int }}\left|{\mathrm{A.}}_3\left(\omega \right)\right|d\omega }}$$

and the fourth normalized amplitude curve $$N_{\mathrm{4th}}\left(\omega \right)=\frac{\left|{\mathrm{A.}}_{\mathrm{4th}}\left(\omega \right)\right|}{{\displaystyle \underset{{\omega }_a}{\overset{{\omega }_b}{\int }}\left|{\mathrm{A.}}_{\mathrm{4th}}\left(\omega \right)\right|d\omega }}$$

over the frequency range relevant for the functionality of the measuring system (here from ω _a until ω _b ) the frequency ( ω ) can be converted into one another in such a way that: $$\left|{\text{N}}_{\mathrm{4th}}\left(\mathrm{\omega }\right)-{\text{N}}_3\left(2\ast \mathrm{\omega }\right)\right|\le \left|{\text{N}}_3\left(2\ast \mathrm{\omega }\right)\right|\ast 10\%,$$

Advantage of the invention

Such an optical measuring system enables, at least in some implementations, a significant reduction in the sensitivity of an optical measuring system to interference signals and EMC radiation. The advantages are not limited to this.

The sensitivity to an on the receiver ( D. ) relevant disturbance variable ( SR ) is thus considerably reduced in the device according to the invention. The improvement also relates to a disturbed physical measured variable

The measuring principle consists of the up or down integration of the demodulated signal, the mixed signal ( S7 ), in a filter ( F1 ), which can be an integrator, low pass but also a band pass. Therefore, the physical property to be measured (ratio of the intensities in the transmission links ( l1 . l2 )) do not scan continuously cyclically. Due to the changes made, however, an interfering signal ( SR ), which is sent to the recipient ( D. ) meet, sample or integrate each other cyclically and constantly. In the 3 and 5 the improved method is shown. The sign of the integrator ( F1 ), contrary to the state of the art cited, is no longer used by the result, the control signal ( S4 ), but controlled by the first clock signal ( clk1 ). Is its period ( T ₁ ) an even (n-fold) multiple of the period ( T ₂ ) of the second clock signal ( clk2 ), the integration takes place in the first filter ( F1 ) always at the same point in time in a clock period of the second clock signal ( clk2 ) and always over full periods ( T ₂ ) of the second clock signal ( clk2 ). This means that there can no longer be a phase error during integration. Together with the second clock signal, which is preferably twice as fast ( clk2 ) the filtered receiver output signal ( S1 ) and / or an amplified receiver output signal ( S2 ) thus cyclically and constantly alternating up and down integrated. This ensures that an interference signal ( SR ) is constantly sampled and therefore continuous integration can take place.

In the exemplary case I (see also 4th ) is determined by the measured variable, the control signal ( S4 ) dependent up or down integration is ensured by the fact that the compensation transmitter ( K ), the third and fourth transmission path ( 13th , 14th ) and the recipient ( D. ) first transmission channel formed only during the negative half-cycle of the second clock signal ( clk2 ) and with a positive value of the control signal ( S4 ) is active. The second clock signal ( clk2 ) is reused here later in the demodulation as part of a multiplication, which removes the minus sign again. The one through the transmitter ( H ), the first transmission link ( 11 ), the object ( O ), the second transmission path ( 12th ) and the recipient ( D. ) The second transmission channel formed is here, for example, only in the case of a positive integration phase, i.e. in the case of a positive half-cycle of the second clock signal ( clk2 ), and a positive value of the control signal ( S4 ) active. This still ensures that (to put it simply), on average over time, the amount of light energy received from the first and second transmission channels via a first filter ( F1 ), which is preferably an integrator or low-pass filter, is regulated in the same way. In the negative half cycle of the second clock signal ( clk2 ) with a positive value of the control signal ( S4 ), on the other hand, is the compensation sender ( K ) active, which is sent directly to the recipient ( D. ) irradiates. In the receive path, the use of the second clock signal then leads to a negative sign, which leads to a progressive reduction in the integration result of the first filter ( F1 ) in this half cycle of the second clock signal ( clk2 ) leads. A digital filter ( FF ) saves the intermediate result as a control signal ( S4 ) at the end of the period ( T ₁ ) of the first clock signal ( clk1 ) starting at the end of a period ( T ₂ ) of the second clock signal ( clk2 ) should coincide in order not to cause phase errors.

In the exemplary case II (see also 3 ) is determined by the measured variable, the control signal ( S4 ) dependent up or down integration is ensured by the fact that the compensation transmitter ( K ), the third and fourth transmission path ( 13th , 14th ) and the recipient ( D. ) first transmission channel formed only during the positive integration phase and with a positive value of the control signal ( S4 ) is active. The positive integration phase occurs when the second clock signal ( clk2 ) is in the positive half-wave. The one through the transmitter ( H ), the first transmission link ( 11 ), the object ( O ), the second transmission path ( 12th ) and the recipient ( D. ), on the other hand, is only available during a positive integration phase, i.e. during the positive half-cycle of the second clock signal ( clk2 ), and a negative value of the control signal ( S4 ) active. This still ensures that (to put it simply), on average over time, the amount of light energy received from the first and second transmission channels via a first filter ( F1 ), which is preferably an integrator or low-pass filter, is regulated in the same way.

First of all, a method for measuring the properties of at least one electromagnetic transmission path and / or an object ( O ) within at least one electromagnetic transmission path ( 11 , 12th , 13th , 14th ) suggested. The method does not necessarily have to be used permanently. It is enough, if the procedure is only used during one observation period.

1. 1. Erzeugen eines ersten Taktsignals (clk1) mit einer ersten Taktperiode (T₁ );
2. 2. Erzeugen eines zweiten Takts (clk2) mit einer zweiten Taktperiode (T₂ ). Diese zweite Taktperiode (T₂ ) ist vorzugsweise nur halb so lang wie die erste Taktperiode (T₁ ), um das Nyquist-Theorem zu erfüllen. Bevorzugt ist die erste Taktperiode (T₁ ) ein ganzzahliges vielfaches der zweiten Taktperiode (T₂ ). Daher ist es beispielsweise denkbar, sowohl die erste, als auch die zweite Taktperiode (T₁ , T₂ ) durch einen einzigen Taktgenerator (G), beispielsweise einen zweistelligen Binärzähler, erzeugen zu lassen, um die Synchronizität sicherzustellen.
3. 3. Mischen, insbesondere Multiplizieren, des ersten Taktsignals (clk1) und des zweiten Taktsignals (clk2) mit einem Regelsignal (S4), das den späteren Messwert darstellt, zu einem Kompensationsvorsignal (S3v);
4. 4. Im Fall I (z.B. Signalpegel zwischen -1 und 1, 4) das Mischen, insbesondere Multiplizieren, des zuvor in einem ersten Inverter (INV1) zu einem komplementären ersten Taktsignal (clk1q) invertierten ersten Taktsignals (clk1) und des in einem zweiten Inverter (INV2) zu einem komplementären zweiten Taktsignal (clk2q) invertierten zweiten Taktsignals (clk2) mit dem Regelsignal (S4) zu einem Sendevorsignal (S5v) und
5. 5. Im Fall II (z.B. Signalpegel zwischen 0 und 1, 3) das Mischen, insbesondere Multiplizieren, des zuvor in einem ersten Inverter (INV1) zu einem komplementären ersten Taktsignal (clk1q) invertierten ersten Taktsignals (clk1) und des zweiten Taktsignals (clk2) mit dem in einem vierten Inverter (INV4) zum komplementären Regelsignal (S4q) modifizierten Regelsignals (S4) zu einem Sendevorsignal (S5v);
6. 6. Erzeugen eines modulierten Sendesignals (S5) mit einer zumindest im Betrachtungszeitraum konstanten ersten Modulationsamplitude in Abhängigkeit vom Sendevorsignal (S5v);
7. 7. Erzeugen eines modulierten Kompensationssignals (S3) in Abhängigkeit vom Kompensationsvorsignal (S3v), das im Vergleich zum Sendesignal (S5) eine von der ersten Modulationsamplitude abweichende zweite Modulationsamplitude aufweisen kann, die im Betrachtungszeitraum konstant ist;
8. 8. Aussenden eines modulierten elektromagnetischen Sendesignals (S5i) durch einen Sender (H) in die erste Übertragungsstrecke (11), wobei die Signalintensität (Signalenergie) dieses modulierten elektromagnetischen Sendesignals (S5i) mit dem Sendesignal (S5) in der Form korreliert, dass zumindest Anteile des ausgesendeten, modulierten elektromagnetischen Sendesignals (S5i) in einem Betrachtungszeitraum, der mehrere Pulse des Sendesignals (S5) umfasst, proportional zum Sendesignal (S5) sind;
9. 9. Aussenden eines elektromagnetischen modulierten Kompensationssignals (S3i) durch einen Kompensationssender (K) in die dritte Übertragungsstrecke (13), wobei die Signalintensität (Signalenergie) dieses modulierten Kompensationssignals (S3i) mit dem Kompensationssignal (S3) in der Form korreliert, dass zumindest Anteile des ausgesendeten elektromagnetischen modulierten Kompensationssignals (S3i) in einem Betrachtungszeitraum, der mehrere Pulse des Kompensationssignals (S3) umfasst, proportional zum Kompensationssignal (S3) sind;
10. 10. Es folgt dann die Wechselwirkung des modulierten elektromagnetischen Sendesignals (S5i) mit der ersten und zweiten Übertragungsstrecke (11, 12) und einem sich darin ggf. befindlichen Objekt (O) und ggf. ebenfalls die Wechselwirkung des elektromagnetischen modulierten Kompensationssignals (S3i) mit der dritten und vierten Übertragungsstrecke (13, 14) und einem darin ggf. befindlichen zweiten Objekt (O2). Dies kann zum Ersten durch Reflexion des modulierten elektromagnetischen Sendesignals (S5i) an einem ersten Objekt (O) und/oder Transmission des modulierten elektromagnetischen Sendesignals (S5i) durch ein erstes Objekt (O) und anschließende Einspeisung des modulierten elektromagnetischen Sendesignals (S5i) als modifiziertes elektromagnetisches Sendesignal (S5s) in eine zweite Übertragungsstrecke (12), wobei die zweite Übertragungsstrecke (12) und/oder die erste Übertragungsstrecke (l1) mit dem ersten Objekt (O) identisch sein können, geschehen. Zum Zweiten kann dies alternativ oder gleichzeitig durch die Reflexion des elektromagnetischen modulierten Kompensationssignals (S3i) an einem zweiten Objekt (O2) und/oder die Transmission des elektromagnetischen modulierten Kompensationssignals (S3i) durch ein zweites Objekt (O2) und anschließende Einspeisung des elektromagnetischen modulierten Kompensationssignals (S3i) als modifiziertes elektromagnetisches Kompensationssignal (S3s) in eine vierte Übertragungsstrecke (14) geschehen. Dabei können die vierte Übertragungsstrecke (14) und/oder die dritte Übertragungsstrecke (13) mit dem zweiten Objekt (O2) identisch sein. Das erste Objekt (O) kann mit dem zweiten Objekt (O2) ebenfalls identisch sein.
11. 11. Es folgt der Austritt des modifizierten elektromagnetischen Sendesignals (S5s) des Senders (H) aus der zweiten Übertragungsstrecke (12), nach Durchgang durch dieselbe und der Empfang des modifizierten elektromagnetischen Sendesignals (S5s) durch einen Empfänger (D), sowie der Austritt des modifizierten elektromagnetischen Kompensationssignals (S3s) des Kompensationssenders (K) aus der vierten Übertragungsstrecke (14) oder dritten Übertragungsstrecke (13), nach Durchgang durch die entsprechende Übertragungsstrecke (13, 14) und der Empfang des ausgetretenen modifizierten elektromagnetischen Kompensationssignals (S3s) durch den Empfänger (D). Der Empfang erfolgt dabei summierend überlagernd und/oder multiplizierend überlagernd mit dem modifizierten elektromagnetischen Sendesignal (S5s) des Senders (H), das aus der zweiten Übertragungsstrecke (12) ausgetreten ist.
12. 12. Ein Empfänger (D) bildet das Empfängerausgangssignal (S0) in Abhängigkeit von der Intensität der empfangenen Überlagerung des aus der zweiten Übertragungsstrecke (12) ausgetretenen modifizierten Sendesignals (S5s) und des aus der vierten Übertragungsstrecke (14) oder dritten Übertragungsstrecke (13) ausgetretenen modulierten elektromagnetischen Kompensationssendesignals (S3s).
13. 13. Die auf Senderseite vorgenommene doppelte Mischung mit einem ersten Taktsignal (clk1) und einem zweiten Taktsignal (clk2) wird nun auf Empfangsseite durch eine zweistufige Demodulation je nach beispielhaftem Fall I (4) oder beispielhaftem Fall II (3) in unterschiedlicher Weise wieder rückgängig gemacht. Es folgt daher in einer ersten Demodulationsstufe die Mischung des Empfängerausgangssignals (S0) oder eines aus dem Empfängerausgangssignal abgeleiteten Signals, insbesondere eines gefilterten Empfängerausgangssignals (S1) oder eines verstärkten Empfängerausgangssignals (S2), einerseits mit dem zweiten Taktsignal (clk2) andererseits, insbesondere in einem ersten Multiplizierer (M1). Dabei entsteht das erste Mischsignal (S6). Diese Entmischung erfolgt vorzugsweise wieder mittels Multiplikation.
14. 14. Des Weiteren folgt dann die zweite Stufe der Demodulation im Fall I durch Mischung des zuvor zum komplementären ersten Taktsignal (clk1q) invertierten ersten Taktsignals (clk1) mit dem ersten Mischsignal (S6) in einem zweiten Multiplizierer (M2). Im Fall II (3) wird das erste Taktsignal (clk1) mit einem negativen Vorzeichen versehen und dem zweiten Multiplizierer (M2) zugeführt. Dabei entsteht das Mischsignal (S7). Da Multiplikationen sowohl das Assoziativgesetz als auch das Kommutativgesetz erfüllen, ist die Reihenfolge der Multiplikationen beliebig. Daher ist es beispielsweise auch denkbar, im Fall I zunächst das komplementäre erste Taktsignal (clk1q) mit dem zweiten Taktsignal (clk2) zu mischen und dann erst das so gewonnene Taktmischsignal einerseits mit dem Empfängerausgangssignal (S0) oder mit einem aus dem Empfängerausgangssignal abgeleiteten Signal, insbesondere einem gefilterten Empfängerausgangssignal (S1) oder mit einem verstärkten Empfängerausgangssignal (S2), andererseits zu mischen. Auch die Multiplikation mit „-1“ kann anders vorgenommen werden. Am Ende ist es nur wichtig, die beiden Taktsignale (clk1 und clk2) so zu mischen, dass ein vorzeichenrichtiges Produkt des Wechselanteils der beiden Taktsignale (clk1, clk2) auf das Empfängerausgangssignal (S0) oder eines der daraus abgeleiteten Signale (S1, S2) aufmultipliziert wird und so eine Demodulation erzielt wird. Die Wahl des Vorzeichens erfolgt dabei so, dass sich Stabilität im Regelkreis einstellt.
15. 15. Es folgt dann wieder eine Filterung des Mischsignals (S7), bevorzugt in einem ersten Filter (F1) zur Bildung eines Regelvorsignals (S8). Besonders bewährt hat sich eine Tiefpassfilterung und/oder Integration als Filtercharakteristik des Filters (F1), da diese einfach zu implementieren sind. Zusammen mit der vorausgegangenen Multiplikation entsteht so ein Skalarprodukt zwischen dem Empfängerausgangssignal (S0) bzw. einem daraus abgeleiteten Signal (S1, S2) und den Wechselsignalanteilen der beiden Taktsignale (clk1 und clk2). Im Fall II ist daher im Entwurf darauf Sorgfalt zu verwenden, dass keine Gleichanteile bei der Skalar-Produktbildung den Integrator, das erste Filter (F1), erreichen können.
16. 16. Als Nächstes folgt dann im Signalpfad eine Analog-zu-Digital-Wandlung des Regelvorsignals (S8) zu einem digitalisierten Regelsignal (S9). Hierfür wird typischerweise ein Analog-zu-Digital-Wandler (ADC) verwendet, bei dem es sich auch nur um einen Komparator mit einem 1-Bit-breitem Ausgang handeln kann. Man erhält ein digitales Regelvorsignal (S9), wobei insbesondere die Digitalisierung auch im Signalpfad vor der Filterung durch den ersten Filter (F1) erfolgen kann. Es ist aber von Vorteil, wenn das Quantisierungsrauschen nicht in den ersten Filter (F1) gelangt.
17. 17. Es folgt dann die Filterung und/oder Verzögerung des digitalen Regelvorsignals (S9), vorzugsweise in einem digitalen Filter (FF) und/oder Flip-Flop, zu dem besagten Regelsignal (S4), wobei insbesondere das digitale Filter (FF) eine Einheit mit dem Analog-zu-Digital-Wandler (ADC) und/oder bei digitaler Realisierung des ersten Filters (F1) mit diesem ersten Filter (F1) eine Einheit bilden kann.
18. 18. Schließlich erfolgt die Ausgabe des Regelsignals (S4) als Messwertsignal für die Eigenschaften zumindest einer der optischen Übertragungsstrecken (11, 12, 13, 14) und/oder zumindest eines der Objekte (O, O2) innerhalb zumindest einer der optischen Übertragungsstrecken (11, 12, 13, 14).

The method has the following steps, which are typically carried out in parallel. So it is not a sequence of steps over time.

1. 1. Generating a first clock signal ( clk1 ) with a first clock period ( T ₁ );
2. 2. Generate a second measure ( clk2 ) with a second clock period ( T ₂ ). This second clock period ( T ₂ ) is preferably only half as long as the first clock period ( T ₁ ) to satisfy the Nyquist theorem. The first clock period is preferred ( T ₁ ) an integer multiple of the second clock period ( T ₂ ). It is therefore conceivable, for example, to use both the first and the second clock period ( T ₁ , T ₂ ) by a single clock generator ( G ), for example a two-digit binary counter, to be generated to ensure synchronicity.
3. 3. Mixing, especially multiplying, the first clock signal ( clk1 ) and the second clock signal ( clk2 ) with a control signal ( S4 ), which represents the later measured value, to a compensation pre-signal ( S3v );
4. 4. In case I (e.g. signal level between -1 and 1, 4th ) the mixing, especially multiplying, of what was previously in a first inverter ( INV1 ) to a complementary first clock signal ( clk1q ) inverted first clock signal ( clk1 ) and the one in a second inverter ( INV2 ) to a complementary second clock signal ( clk2q ) inverted second clock signal ( clk2 ) with the control signal ( S4 ) to a pre-send signal ( S5v ) and
5. 5. In case II (e.g. signal level between 0 and 1, 3 ) the mixing, especially multiplying, of what was previously in a first inverter ( INV1 ) to a complementary first clock signal ( clk1q ) inverted first clock signal ( clk1 ) and the second clock signal ( clk2 ) with the one in a fourth inverter ( INV4 ) to the complementary control signal ( S4q ) modified control signal ( S4 ) to a pre-send signal ( S5v );
6. 6. Generation of a modulated transmission signal ( S5 ) with a first modulation amplitude that is constant at least in the observation period as a function of the transmission pre-signal ( S5v );
7. 7. Generation of a modulated compensation signal ( S3 ) depending on the compensation signal ( S3v ), which compared to the transmitted signal ( S5 ) can have a second modulation amplitude which differs from the first modulation amplitude and which is constant in the observation period;
8. 8. Sending a modulated electromagnetic transmission signal ( S5i ) by a transmitter ( H ) into the first transmission path ( 11 ), where the signal intensity (signal energy) of this modulated electromagnetic transmission signal ( S5i ) with the transmission signal ( S5 ) correlated in such a way that at least parts of the emitted, modulated electromagnetic transmission signal ( S5i ) in an observation period that includes several pulses of the transmission signal ( S5 ), proportional to the transmitted signal ( S5 ) are;
9. 9. Sending an electromagnetic modulated compensation signal ( S3i ) by a compensation transmitter ( K ) into the third transmission path ( 13th ), where the signal intensity (signal energy) of this modulated compensation signal ( S3i ) with the compensation signal ( S3 ) correlated in such a way that at least parts of the emitted electromagnetic modulated compensation signal ( S3i ) in an observation period that includes several pulses of the compensation signal ( S3 ), proportional to the compensation signal ( S3 ) are;
10. 10. This is followed by the interaction of the modulated electromagnetic transmission signal ( S5i ) with the first and second transmission path ( 11 , 12th ) and an object that may be in it ( O ) and possibly also the interaction of the electromagnetic modulated compensation signal ( S3i ) with the third and fourth transmission path ( 13th , 14th ) and a second object that may be in it ( O2 ). First of all, this can be done by reflecting the modulated electromagnetic transmission signal ( S5i ) on a first object ( O ) and / or transmission of the modulated electromagnetic transmission signal ( S5i ) through a first object ( O ) and subsequent feeding in of the modulated electromagnetic transmission signal ( S5i ) as a modified electromagnetic transmission signal ( S5s ) into a second transmission path ( 12th ), where the second transmission path ( 12th ) and / or the first transmission path ( l1 ) with the first object ( O ) can be identical. Secondly, this can alternatively or simultaneously by reflecting the electromagnetic modulated compensation signal ( S3i ) on a second object ( O2 ) and / or the transmission of the electromagnetic modulated compensation signal ( S3i ) through a second object ( O2 ) and subsequent feed of the electromagnetic modulated compensation signal ( S3i ) as a modified electromagnetic compensation signal ( S3s ) into a fourth transmission path ( 14th ) happen. The fourth transmission path ( 14th ) and / or the third transmission path ( 13th ) with the second object ( O2 ) be identical. The first object ( O ) can be used with the second object ( O2 ) must also be identical.
11. 11. This is followed by the exit of the modified electromagnetic transmission signal ( S5s ) of the sender ( H ) from the second transmission path ( 12th ), after passing through it and receiving the modified electromagnetic transmission signal ( S5s ) by a recipient ( D. ), as well as the exit of the modified electromagnetic compensation signal ( S3s ) of the compensation transmitter ( K ) from the fourth transmission path ( 14th ) or third transmission path ( 13th ), after passing through the corresponding transmission link ( 13th , 14th ) and the receipt of the leaked modified electromagnetic compensation signal ( S3s ) by the recipient ( D. ). The reception is cumulatively superimposed and / or multiplied superimposed on the modified electromagnetic transmission signal ( S5s ) of the sender ( H ) from the second transmission link ( 12th ) has left.
12. 12. A recipient ( D. ) forms the receiver output signal ( S0 ) depending on the intensity of the received overlay of the from the second transmission path ( 12th ) exited modified transmission signal ( S5s ) and the one from the fourth transmission path ( 14th ) or third transmission path ( 13th ) leaked modulated electromagnetic compensation transmission signal ( S3s ).
13. 13. The double mixing carried out on the transmitter side with a first clock signal ( clk1 ) and a second clock signal ( clk2 ) is now on the receiving side by a two-stage demodulation depending on the exemplary case I ( 4th ) or exemplary case II ( 3 ) reversed in different ways. In a first demodulation stage, the receiver output signal is mixed ( S0 ) or a signal derived from the receiver output signal, in particular a filtered receiver output signal ( S1 ) or an amplified receiver output signal ( S2 ), on the one hand with the second clock signal ( clk2 ) on the other hand, especially in a first multiplier ( M1 ). This creates the first mixed signal ( S6 ). This segregation is preferably carried out again by means of multiplication.
14. 14. The second stage of demodulation then follows in case I by mixing the previously complementary first clock signal ( clk1q ) inverted first clock signal ( clk1 ) with the first mixed signal ( S6 ) in a second multiplier ( M2 ). In case II ( 3 ) the first clock signal ( clk1 ) with a negative sign and the second multiplier ( M2 ) supplied. This creates the mixed signal ( S7 ). Since multiplications satisfy both the associative law and the commutative law, the order of the multiplications is arbitrary. It is therefore also conceivable, for example, to first use the complementary first clock signal ( clk1q ) with the second clock signal ( clk2 ) and only then to mix the clock mix signal obtained in this way with the receiver output signal ( S0 ) or with a signal derived from the receiver output signal, in particular a filtered receiver output signal ( S1 ) or with an amplified receiver output signal ( S2 ), on the other hand to mix. The multiplication by “-1” can also be done differently. In the end it is only important to use the two clock signals ( clk1 and clk2 ) to be mixed in such a way that a product with the correct sign of the alternating component of the two clock signals ( clk1 , clk2 ) to the receiver output signal ( S0 ) or one of the signals derived from it ( S1 , S2 ) is multiplied and thus a demodulation is achieved. The sign is chosen in such a way that stability is achieved in the control loop.
15. 15. The mixed signal is then filtered again ( S7 ), preferably in a first filter ( F1 ) to generate a control signal ( S8 ). Low-pass filtering and / or integration as the filter characteristic of the filter ( F1 ) as they are easy to implement. Together with the previous multiplication, this creates a scalar product between the receiver output signal ( S0 ) or a signal derived from it ( S1 , S2 ) and the alternating signal components of the two clock signals ( clk1 and clk2 ). In case II, care must be taken in the design to ensure that no constant components are used in the scalar product formation, the integrator, the first filter ( F1 ), reachable.
16. 16. The next step in the signal path is an analog-to-digital conversion of the control signal ( S8 ) to a digitized control signal ( S9 ). An analog-to-digital converter ( ADC ), which can also be just a comparator with a 1-bit wide output. A digital control signal is obtained ( S9 ), whereby in particular the digitization also in the signal path before the filtering by the first filter ( F1 ) can be done. However, it is advantageous if the quantization noise is not in the first filter ( F1 ) arrives.
17. 17. This is followed by the filtering and / or delay of the digital pre-control signal ( S9 ), preferably in a digital filter ( FF ) and / or flip-flop, to the said control signal ( S4 ), whereby in particular the digital filter ( FF ) a unit with the analog-to-digital converter ( ADC ) and / or with digital implementation of the first filter ( F1 ) with this first filter ( F1 ) can form a unit.
18. 18. Finally, the control signal is output ( S4 ) as a measured value signal for the properties of at least one of the optical transmission links ( 11 , 12th , 13th , 14th ) and / or at least one of the objects ( O , O2 ) within at least one of the optical transmission links ( 11 , 12th , 13th , 14th ).

In a more general form, the method can be described as follows: In this more general form, it is also a method for measuring the properties of at least one electromagnetic transmission path and / or an object ( O ) within at least one electromagnetic transmission path ( 11 , 12th , 13th , 14th ) for use during an observation period.

• Erzeugen eines bandbegrenzten Taktsignals (clk1 × ckl2) und eines dazu komplementären bandbegrenzten Taktsignals (clk1q × ckl2q). Dabei besitzt das bandbegrenzte Taktsignal (clk1 × ckl2) und damit auch das komplementäre bandbegrenzte Taktsignal (clk1q × ckl2q) eine betragsmäßige untere Grenzfrequenz ω_u und eine betragsmäßige obere Grenzfrequenz ω_o mit einer betragsmäßigen Frequenzbandbreite Δω=ω_ο-ω_u und einer betragsmäßigen Mittenfrequenz ω_m = Δω/2+ω_u. Dass bandbegrenzte Taktsignal (clk1 × ckl2) ist zeitlich oder im Frequenzspektrum dabei so strukturiert ist, dass es als Ergebnis der Multiplikation eines ersten Taktsignals (clk1) mit einem zweiten Taktsignal (clk2) im Zeitbereich aufgefasst werden kann. Das komplementäre bandbegrenzte Taktsignal (clk1q × ckl2q) ist ebenfalls zeitlich oder im Frequenzspektrum so strukturiert, dass es als Ergebnis der Multiplikation eines komplementären ersten Taktsignals (clk1q) mit einem komplementären zweiten Taktsignal (clk2q) im Zeitbereich aufgefasst werden kann. Das komplementäre erste Taktsignal (clklq) ist dabei komplementär zum ersten Taktsignal (clk1). Das komplementäre zweite Taktsignal (clk2q) ist dabei komplementär zum zweiten Taktsignal (clk2). Das erste Taktsignal (clk1) weist ein erstes Frequenzspektrum (A₁ (ω)) hinsichtlich seiner Amplitude auf. Das zweite Taktsignal (clk2q) weist ein zweites Frequenzspektrum (A₂(ω)) hinsichtlich seiner Amplitude auf. Das komplementäre erste Taktsignal (clklq) weist ein drittes Frequenzspektrum (A₃(ω)) hinsichtlich seiner Amplitude auf. Das komplementäre zweite Taktsignal (clk2) weist ein viertes Frequenzspektrum (A₄(ω)) hinsichtlich seiner Amplitude auf. Dabei können der erste normierte Amplitudenverlauf (N₁(ω)=|A₁(ω)|/∫|A₁(ω)|dω) und der zweite normierte Amplitudenverlauf (N₂(ω)=|A₂(ω)|/∫|A₂(ω)|dω) über den für die Funktionstüchtigkeit des Messsystems relevanten Frequenzbereich der Frequenz (ω) ineinander derart überführt werden, dass gilt: |N₂(ω)-N₁(2*ω)|≤|N₁(2*ω)|*10%. Ebenso können der dritte normierte Amplitudenverlauf (N₃(ω)=|A₃(ω)|/∫A₃(ω)|dω) und der vierte normierte Amplitudenverlauf (N₄(ω)=|A₄(ω)||/∫|A₄(ω)|dω) über den für die Funktionstüchtigkeit des Messsystems relevanten Frequenzbereich der Frequenz (ω) ineinander derart überführt werden, dass gilt: |N₄(ω)-N₃(2*ω)|≤|N₃(2*ω)|*10%;

In case I ( 4th ) do the following general steps:

• Generation of a band-limited clock signal ( clk1 × ckl2 ) and a complementary band-limited clock signal ( clk1q × ckl2q ). The band-limited clock signal (c lk1 × ckl2 ) and thus also the complementary band-limited clock signal ( clk1q × ckl2q ) an absolute lower limit frequency ω _u and an upper limit frequency in terms of magnitude ω _o with an absolute frequency bandwidth Δω = ω _ο -ω _u and an absolute center frequency ω _m = Δω / 2 + ω _u . The band-limited clock signal ( clk1 × ckl2 ) is structured in terms of time or frequency spectrum in such a way that it is the result of the multiplication of a first clock signal ( clk1 ) with a second clock signal ( clk2 ) can be understood in the time domain. The complementary band-limited clock signal ( clk1q × ckl2q ) is also structured in terms of time or frequency spectrum in such a way that it is the result of the multiplication of a complementary first clock signal ( clk1q ) with a complementary second clock signal ( clk2q ) can be understood in the time domain. The complementary first clock signal ( clklq ) is complementary to the first clock signal ( clk1 ). The complementary second clock signal ( clk2q ) is complementary to the second clock signal ( clk2 ). The first clock signal ( clk1 ) has a first frequency spectrum ( A ₁ ( ω )) in terms of its amplitude. The second clock signal ( clk2q ) has a second frequency spectrum (A ₂ ( ω )) in terms of its amplitude. The complementary first clock signal ( clklq ) has a third frequency spectrum (A ₃ ( ω )) in terms of its amplitude. The complementary second clock signal ( clk2 ) has a fourth frequency spectrum (A ₄ ( ω )) in terms of its amplitude. The first standardized amplitude curve (N ₁ (ω) = | A ₁ (ω) | / ∫ | A ₁ (ω) | dω) and the second standardized amplitude curve (N ₂ (ω) = | A ₂ (ω) | / ∫ | A ₂ (ω) | dω) above that for the functionality of the measuring system relevant frequency range of the frequency ( ω ) are converted into one another in such a way that the following applies: | N ₂ (ω) -N ₁ (2 * ω) | ≤ | N ₁ (2 * ω) | * 10%. The third standardized amplitude _{curve (N 3} (ω) = | A ₃ (ω) | / ∫A ₃ (ω) | dω) and the fourth standardized amplitude curve (N ₄ (ω) = | A ₄ (ω) || / ∫ | A ₄ (ω) | dω) over the frequency range relevant for the functionality of the measuring system ( ω ) are converted into one another in such a way that the following applies: | N ₄ (ω) -N ₃ (2 * ω) | ≤ | N ₃ (2 * ω) | * 10%;

• Erzeugen eines ersten bandbegrenzten Taktsignals (clk1 × ckl2) und eines zweiten bandbegrenzten Taktsignals (clk1q × ckl2). Dabei besitzen das erste bandbegrenzte Taktsignal (clk1 × ckl2) und das zweite bandbegrenzte Taktsignal (clklq × ckl2) eine gemeinsame betragsmäßige untere Grenzfrequenz ω_u und eine gemeinsame betragsmäßige obere Grenzfrequenz ω_o mit einer gemeinsamen betragsmäßigen Frequenzbandbreite Δω=ω_ο-ω_u und einer gemeinsamen betragsmäßigen Mittenfrequenz ω_m = Δω/2+ω_u. Dass erste bandbegrenzte Taktsignal (clkl × ckl2) ist zeitlich oder im Frequenzspektrum dabei so strukturiert ist, dass es als Ergebnis der Multiplikation eines ersten Taktsignals (clk1) mit einem zweiten Taktsignal (clk2) im Zeitbereich aufgefasst werden kann. Das zweite bandbegrenzte Taktsignal (clk1 × ckl2) ist ebenfalls zeitlich oder im Frequenzspektrum so strukturiert, dass es als Ergebnis der Multiplikation eines komplementären ersten Taktsignals (clklq) mit dem besagten komplementären zweiten Taktsignal (clk2) im Zeitbereich aufgefasst werden kann. Das komplementäre erste Taktsignal (clk1q) ist komplementär zum ersten Taktsignal (clk1). Das erste Taktsignal (clk1) weist wieder ein erstes Frequenzspektrum (A₁ (ω)) hinsichtlich seiner Amplitude auf. Das zweite Taktsignal (clk2q) weist wieder ein zweites Frequenzspektrum (A₂(ω)) hinsichtlich seiner Amplitude auf. Das komplementäre erste Taktsignal (clk1q) weist wieder ein drittes Frequenzspektrum (A₃(ω)) hinsichtlich seiner Amplitude auf. Dabei können der erste normierte Amplitudenverlauf (N₁((ω)= |A₁(ω)|/∫|A₁(ω)|dω) und der zweite normierte Amplitudenverlauf (N₂(ω)=|A₂(ω)|/∫|A₂(ω)|dω) über den für die Funktionstüchtigkeit des Messsystems relevanten Frequenzbereich der Frequenz (ω) ineinander derart überführt werden, dass gilt:
  • |N₂(ω)-N₁(2*ω) ≤|N₁(2*ω)|*10%. Ebenso können der dritte normierte Amplitudenverlauf (N₃(ω)=|A₃(ω)|/∫|A₃(ω)|dω) und der zweite normierte Amplitudenverlauf (N₄(ω)) über den für die Funktionstüchtigkeit des Messsystems relevanten Frequenzbereich der Frequenz (ω) ineinander derart überführt werden, dass gilt: |N₂(ω)-N₃(2*ω) ≤|N₃(2*ω)|*10%;

In case II ( 3 ) (e.g. signal level of the first clock signal between 0 and 1) the following general steps:

• Generation of a first band-limited clock signal ( clk1 × ckl2 ) and a second band-limited clock signal ( clk1q × ckl2 ). The first band-limited clock signal ( clk1 × ckl2 ) and the second band-limited clock signal ( clklq × ckl2 ) a common lower limit frequency in terms of absolute value ω _u and a common absolute upper limit frequency ω _o with a common absolute frequency bandwidth Δω = ω _ο -ω _u and a common absolute center frequency ω _m = Δω / 2 + ω _u . The first band-limited clock signal (clkl × ckl2) is structured in terms of time or in the frequency spectrum in such a way that it is the result of the multiplication of a first clock signal ( clk1 ) with a second clock signal ( clk2 ) can be understood in the time domain. The second band-limited clock signal (clk1 × ckl2) is also structured in terms of time or frequency spectrum in such a way that it is the result of the multiplication of a complementary first clock signal (clklq ) with said complementary second clock signal ( clk2 ) can be understood in the time domain. The complementary first clock signal ( clk1q ) is complementary to the first clock signal ( clk1 ). The first clock signal ( clk1 ) again has a first frequency spectrum ( A ₁ ( ω )) in terms of its amplitude. The second clock signal ( clk2q ) again has a second frequency spectrum (A ₂ ( ω )) in terms of its amplitude. The complementary first clock signal ( clk1q ) again has a third frequency spectrum (A ₃ ( ω )) in terms of its amplitude. The first normalized amplitude curve (N ₁ ((ω) = | A ₁ (ω) | / ∫ | A ₁ (ω) | dω) and the second normalized amplitude curve (N ₂ (ω) = | A ₂ (ω) | / ∫ | A ₂ (ω) | dω) over the frequency range of the frequency ( ω ) are converted into each other in such a way that:
  • | N ₂ (ω) -N ₁ (2 * ω) ≤ | N ₁ (2 * ω) | * 10%. The third normalized amplitude curve (N ₃ (ω) = | A ₃ (ω) | / ∫ | A ₃ (ω) | dω) and the second normalized amplitude curve ( N ₄ (ω) ) over the frequency range relevant for the functionality of the measuring system ( ω ) are converted into one another in such a way that the following applies: | N ₂ (ω) -N ₃ (2 * ω) ≤ | N ₃ (2 * ω) | * 10%;

The following two steps 2 and 3 can also be implemented differently.

• Mischen, insbesondere Multiplizieren, des bandbegrenzten Taktsignals (clk1 × clk2) und eines Regelsignals (S4) zu einem Kompensationsvorsignal (S3v) oder Multiplizieren des ersten Taktsignals (clk1) und des zweiten Taktsignals (clk2) und des Regelsignals (S4) zu einem Kompensationsvorsignal (S3v);
  1. 1. Mischen, insbesondere Multiplizieren, des bandbegrenzten komplementären Taktsignals (clk1q × ckl2q) und des Regelsignals (S4) zu einem Sendevorsignal (S5v) oder Multiplizieren des komplementären ersten Taktsignals (clk1q) und des komplementären zweiten Taktsignals (clk2q) und des Regelsignals (S4) zu einem Sendevorsignal (S5v);

In case I ( 4th ):

• Mixing, especially multiplying, of the band-limited clock signal ( clk1 × clk2 ) and a control signal ( S4 ) to a compensation pre-signal ( S3v ) or multiplying the first clock signal ( clk1 ) and the second clock signal ( clk2 ) and the control signal ( S4 ) to a compensation pre-signal ( S3v );
  1. 1. Mixing, especially multiplying, of the band-limited complementary clock signal ( clk1q × ckl2q ) and the control signal ( S4 ) to a pre-send signal ( S5v ) or multiplying the complementary first clock signal ( clk1q ) and the complementary second clock signal ( clk2q ) and the control signal ( S4 ) to a pre-send signal ( S5v );

• 2. Mischen, insbesondere Multiplizieren, des ersten Taktsignals (clk1) und des zweiten Taktsignals (clk2) und des Regelsignals (S4) zu einem Kompensationsvorsignal (S3v) und
• 3. Mischen, insbesondere Multiplizieren, des komplementären ersten Taktsignals (clk1q) und des komplementären zweiten Taktsignals (clk2q) und des Regelsignals (S4) zu einem Sendevorsignal (S5v);

The alternative involves two steps

• 2. Mixing, especially multiplying, the first clock signal ( clk1 ) and the second clock signal ( clk2 ) and the control signal ( S4 ) to a compensation pre-signal ( S3v ) and
• 3. Mixing, in particular multiplying, of the complementary first clock signal ( clk1q ) and the complementary second clock signal ( clk2q ) and the control signal ( S4 ) to a pre-send signal ( S5v );

• Mischen, insbesondere Multiplizieren, des ersten bandbegrenzten Taktsignals (clk1 × clk2) und eines Regelsignals (S4) zu einem Kompensationsvorsignal (S3v) oder Multiplizieren des ersten Taktsignals (clk1) und des zweiten Taktsignals (clk2) und des Regelsignals (S4) zu einem Kompensationsvorsignal (S3v);

1. 1. Mischen, insbesondere Multiplizieren, des zweiten bandbegrenzten Taktsignals (clk1q × ckl2) und des zum Regelsignal (S4) komplementären Regelsignals (S4q) zu einem Sendevorsignal (S5v) oder Multiplizieren des komplementären ersten Taktsignals (clk1q) und des zweiten Taktsignals (clk2) und des komplementären Regelsignals (S4q) zu einem Sendevorsignal (S5v);

In case II ( 3 ):

• Mixing, especially multiplying, of the first band-limited clock signal ( clk1 × clk2 ) and a control signal ( S4 ) to a compensation pre-signal ( S3v ) or multiplying the first clock signal ( clk1 ) and the second clock signal ( clk2 ) and the control signal ( S4 ) to a compensation pre-signal ( S3v );

1. 1. Mixing, in particular multiplying, of the second band-limited clock signal ( clk1q × ckl2 ) and the control signal ( S4 ) complementary control signal ( S4q ) to a pre-send signal ( S5v ) or multiplying the complementary first clock signal ( clk1q ) and the second clock signal ( clk2 ) and the complementary control signal ( S4q ) to a pre-send signal ( S5v );

1. 1. Mischen, insbesondere Multiplizieren, des ersten Taktsignals (clk1) und des zweiten Taktsignals (clk2) und des Regelsignals (S4) zu einem Kompensationsvorsignal (S3v) und
2. 2. Mischen, insbesondere Multiplizieren, des komplementären ersten Taktsignals (clk1q) und des zweiten Taktsignals (clk2) und des komplementären Regelsignals (S4q) zu einem Sendevorsignal (S5v);

The alternative for case II (e.g. signal level of the first clock signal ( clk1 ) and the second clock signal ( clk2 ) between 0 and 1) comprises the two steps

1. 1. Mixing, especially multiplying, the first clock signal ( clk1 ) and the second clock signal ( clk2 ) and the control signal ( S4 ) to a compensation pre-signal ( S3v ) and
2. 2. Mixing, in particular multiplying, of the complementary first clock signal ( clk1q ) and the second clock signal ( clk2 ) and the complementary control signal ( S4q ) to a pre-send signal ( S5v );

1. 1. Aussenden eines modulierten elektromagnetischen Sendesignals (S5i) durch einen Sender (H) in die erste Übertragungsstrecke (11), wobei die Signalintensität (Signalenergie) dieses modulierten elektromagnetischen Sendesignals (S5i) mit dem Sendesignal (S5) in der Form korreliert, dass zumindest Anteile des ausgesendeten modulierten elektromagnetischen Sendesignals (S5i) in einem Betrachtungszeitraum, der mehrere Pulse des Sendesignals (S5) umfasst, proportional zum Sendesignal (S5) sind;
2. 2. Aussenden eines elektromagnetischen modulierten Kompensationssignals (S3i) durch einen Kompensationssender (K) in die dritte Übertragungsstrecke (13), wobei die Signalintensität (Signalenergie) dieses modulierten Kompensationssignals (S3i) mit dem Kompensationssignal (S3) in der Form korreliert, dass zumindest Anteile des ausgesendeten elektromagnetischen modulierten Kompensationssignals (S3i) in einem Betrachtungszeitraum, der mehrere Pulse des Kompensationssignals (S3) umfasst, proportional zum Kompensationssignal (S3) sind;
3. 3. Einen oder mehrere der beiden Schritte
   1. a. Reflexion des modulierten elektromagnetischen Sendesignals (S5i) an einem ersten Objekt (O) und/oder Transmission des modulierten elektromagnetischen Sendesignals (S5i) durch ein erstes Objekt (O) und anschließende Einspeisung des modulierten elektromagnetischen Sendesignals (S5i) als modifiziertes elektromagnetisches Sendesignal (S5s) in eine zweite Übertragungsstrecke (12), wobei die zweite Übertragungsstrecke (12) und/oder die erste Übertragungsstrecke (l1) mit dem ersten Objekt (O) identisch sein können, und/oder
   2. b. Reflexion des elektromagnetischen modulierten Kompensationssignals (S3i) an einem zweiten Objekt (O2) und/oder Transmission des elektromagnetischen modulierten Kompensationssignals (S3i) durch ein zweites Objekt (O2) und anschließende Einspeisung des elektromagnetischen modulierten Kompensationssignals (S3i) als modifiziertes elektromagnetisches Kompensationssignal (S3s) in eine vierte Übertragungsstrecke (14), wobei die vierte Übertragungsstrecke (14) und/oder die dritte Übertragungsstrecke (13) mit dem zweiten Objekt (O2) identisch sein können und wobei das erste Objekt (O) mit dem zweiten Objekt (O2) ebenfalls identisch sein kann;
4. 4. Austritt des modifizierten elektromagnetischen Sendesignals (S5s) des Senders (H) aus der zweiten Übertragungsstrecke (12), nach Durchgang durch dieselbe und Empfang des modifizierten elektromagnetischen Sendesignals (S5s) durch einen Empfänger (D);
5. 5. Austritt des modifizierten elektromagnetischen Kompensationssignals (S3s) des Kompensationssenders (K) aus der vierten Übertragungsstrecke (14) oder dritten Übertragungsstrecke (13), nach Durchgang durch die entsprechende Übertragungsstrecke (13, 14) und Empfang des ausgetretenen modifizierten elektromagnetischen Kompensationssignals (S3s) durch den Empfänger (D), wobei der Empfang summierend und/oder multiplizierend mit dem modifizierten elektromagnetischen Sendesignal (S5s) des Senders (H), das aus der zweiten Übertragungsstrecke (12) ausgetreten ist, als Empfang einer Überlagerung erfolgt;
6. 6. Bilden eines Empfängerausgangssignals (S0) durch den Empfänger (D) in Abhängigkeit von der empfangenen Überlagerung des aus der zweiten Übertragungsstrecke (12) ausgetretenen modifizierten Sendesignals (S5s) und des aus der vierten Übertragungsstrecke (14) oder dritten Übertragungsstrecke (13) ausgetretenen modulierten elektromagnetischen Kompensationssendesignals (S3s);

The next step is for both cases I and II:

1. 1. Sending a modulated electromagnetic transmission signal ( S5i ) by a transmitter ( H ) into the first transmission path ( 11 ), where the signal intensity (signal energy) of this modulated electromagnetic transmission signal ( S5i ) with the transmission signal ( S5 ) correlated in such a way that at least parts of the emitted modulated electromagnetic transmission signal ( S5i ) in an observation period that includes several pulses of the transmission signal ( S5 ), proportional to the transmitted signal ( S5 ) are;
2. 2. Sending an electromagnetic modulated compensation signal ( S3i ) by a compensation transmitter ( K ) into the third transmission path ( 13th ), where the signal intensity (signal energy) of this modulated compensation signal ( S3i ) with the compensation signal ( S3 ) correlated in such a way that at least parts of the emitted electromagnetic modulated compensation signal ( S3i ) in an observation period that includes several pulses of the compensation signal ( S3 ), proportional to the compensation signal ( S3 ) are;
3. 3. One or more of the two steps
   1. a. Reflection of the modulated electromagnetic transmission signal ( S5i ) on a first object ( O ) and / or transmission of the modulated electromagnetic transmission signal ( S5i ) through a first object ( O ) and subsequent feeding in of the modulated electromagnetic transmission signal ( S5i ) as a modified electromagnetic transmission signal ( S5s ) into a second transmission path ( 12th ), where the second transmission path ( 12th ) and / or the first transmission path ( l1 ) with the first object ( O ) can be identical, and / or
   2. b. Reflection of the electromagnetic modulated compensation signal ( S3i ) on a second object ( O2 ) and / or transmission of the electromagnetic modulated compensation signal ( S3i ) through a second object ( O2 ) and subsequent feed of the electromagnetic modulated compensation signal ( S3i ) as a modified electromagnetic compensation signal ( S3s ) into a fourth transmission path ( 14th ), the fourth transmission path ( 14th ) and / or the third transmission path ( 13th ) with the second object ( O2 ) can be identical and where the first object ( O ) with the second object ( O2 ) can also be identical;
4. 4. Exit of the modified electromagnetic transmission signal ( S5s ) of the sender ( H ) from the second transmission path ( 12th ), after passing through it and receiving the modified electromagnetic transmission signal ( S5s ) by a recipient ( D. );
5. 5. Exit of the modified electromagnetic compensation signal ( S3s ) of the compensation transmitter ( K ) from the fourth transmission path ( 14th ) or third transmission path ( 13th ), after passing through the corresponding transmission link ( 13th , 14th ) and receipt of the leaked modified electromagnetic compensation signal ( S3s ) by the recipient ( D. ), the reception adding and / or multiplying with the modified electromagnetic transmission signal ( S5s ) of the sender ( H ) from the second transmission link ( 12th ) emerged when an overlay was received;
6. 6. Forming a receiver output signal ( S0 ) by the recipient ( D. ) depending on the received superimposition of the from the second transmission path ( 12th ) exited modified transmission signal ( S5s ) and the one from the fourth transmission path ( 14th ) or third transmission path ( 13th ) leaked modulated electromagnetic compensation transmission signal ( S3s );

The demodulation can again be done in different ways:

• 7. Bilden eines ersten Mischsignals (S6) durch Multiplikation des Empfängerausgangssignals (S0) oder eines aus dem Empfängerausgangssignal (S0) abgeleiteten Signals, insbesondere eines gefilterten Empfängerausgangssignals (S1) oder eines verstärkten Empfängerausgangssignals (S2), einerseits mit dem zweiten Taktsignal (clk2), insbesondere in einem ersten Multiplizierer (M1), andererseits;
• 8. Bilden eines Mischsignals (S7) im Fall I durch Multiplikation des komplementären ersten Taktsignals (clk1q) mit dem ersten Mischsignal (S6) und im Fall II durch Multiplikation des ersten Taktsignals (clk1) mit einem Faktor -1 und mit dem ersten Mischsignal (S6), wobei diese Multiplikationen insbesondere in einem zweiten Multiplizierer (M2) erfolgen;

As a first option:

• 7. Forming a first mixed signal ( S6 ) by multiplying the receiver output signal ( S0 ) or one of the receiver output signal ( S0 ) derived signal, in particular a filtered receiver output signal ( S1 ) or an amplified receiver output signal ( S2 ), on the one hand with the second clock signal ( clk2 ), especially in a first multiplier ( M1 ), on the other hand;
• 8. Forming a mixed signal ( S7 ) in case I by multiplying the complementary first clock signal ( clk1q ) with the first mixed signal ( S6 ) and in case II by multiplying the first clock signal ( clk1 ) with a factor of -1 and with the first mixed signal ( S6 ), these multiplications in particular in a second multiplier ( M2 ) respectively;

• 9. Bilden eines Mischsignals (S7) durch Mischung, insbesondere Multiplikation, des Empfängerausgangssignals (S0) oder eines aus dem Empfängerausgangssignal abgeleiteten Signals, insbesondere eines gefilterten Empfängerausgangssignals (S1) oder eines verstärkten Empfängerausgangssignals (S2), einerseits mit dem zweiten Taktsignal (clk2) und im Fall I mit dem komplementären ersten Taktsignal (clk1q) und im Fall II mit dem mit -1 multiplizierten ersten Taktsignal (clk1), insbesondere in einem dritten Mischer (Mi3)

As a second option

• 9. Forming a mixed signal ( S7 ) by mixing, especially multiplication, of the receiver output signal ( S0 ) or a signal derived from the receiver output signal, in particular a filtered receiver output signal ( S1 ) or an amplified receiver output signal ( S2 ), on the one hand with the second clock signal ( clk2 ) and in case I with the complementary first clock signal ( clk1q ) and in case II with the first clock signal multiplied by -1 ( clk1 ), especially in a third mixer ( Wed3 )

• 10. Im Fall I (4): Bilden eines Mischsignals (S7) durch Mischung, insbesondere Multiplikation, des Empfängerausgangssignals (S0) oder eines aus dem Empfängerausgangssignal abgeleiteten Signals, insbesondere eines gefilterten Empfängerausgangssignals (S1) oder eines verstärkten Empfängerausgangssignals (S2), einerseits mit dem zweiten Taktsignal (clk2) und mit dem ersten Taktsignal (clk1) und anschließende Multiplikation mit -1, insbesondere in einem dritten Mischer (Mi3)

As a third option

• 10. In case I ( 4th ): Forming a mixed signal ( S7 ) by mixing, especially multiplication, of the receiver output signal ( S0 ) or a signal derived from the receiver output signal, in particular a filtered receiver output signal ( S1 ) or an amplified receiver output signal ( S2 ), on the one hand with the second clock signal ( clk2 ) and with the first clock signal ( clk1 ) and subsequent multiplication by -1, especially in a third mixer ( Wed3 )

• 11. Im Fall I (4): Bilden eines Mischsignals (S7) durch Mischung, insbesondere Multiplikation, des Empfängerausgangssignals (S0) oder eines aus dem Empfängerausgangssignal abgeleiteten Signals, insbesondere eines gefilterten Empfängerausgangssignals (S1) oder eines verstärkten Empfängerausgangssignals (S2), einerseits mit dem bandbreitenbegrenzten Taktsignal (clk1 × clk2) und anschließende Multiplikation mit -1, insbesondere in einem dritten Mischer (Mi3);

As a fourth option

• 11. In case I ( 4th ): Forming a mixed signal ( S7 ) by mixing, especially multiplication, of the receiver output signal ( S0 ) or a signal derived from the receiver output signal, in particular a filtered receiver output signal ( S1 ) or an amplified receiver output signal ( S2 ), on the one hand with the bandwidth-limited clock signal ( clk1 × clk2 ) and subsequent multiplication by -1, especially in a third mixer ( Wed3 );

• 12. Im Fall I (4): Bilden eines Mischsignals (S7) durch Mischung, insbesondere Multiplikation, des Empfängerausgangssignals (S0) oder eines aus dem Empfängerausgangssignal abgeleiteten Signals, insbesondere eines gefilterten Empfängerausgangssignals (S1) oder eines verstärkten Empfängerausgangssignals (S2), einerseits mit dem komplementären bandbreitenbegrenzten Taktsignal (clk1q × clk2q) und anschließende Multiplikation mit -1, insbesondere in einem dritten Mischer (Mi3);

As a fifth option

• 12. In case I ( 4th ): Forming a mixed signal ( S7 ) by mixing, especially multiplication, of the receiver output signal ( S0 ) or a signal derived from the receiver output signal, in particular a filtered receiver output signal ( S1 ) or an amplified receiver output signal ( S2 ), on the one hand with the complementary bandwidth-limited clock signal ( clk1q × clk2q ) and subsequent multiplication by -1, especially in a third mixer ( Wed3 );

• 13. Filterung - insbesondere Tiefpassfilterung und/oder Integration - des Mischsignals (S7), insbesondere in einem ersten Filter (F1), zur Bildung eines Regelvorsignals (S8);
• 14. Analog-zu-Digital-Wandlung des Regelvorsignals (S8) zu einem digitalisierten Regelsignal (S9), insbesondere in einem Analog-zu-Digital-Wandler (ADC), um ein digitales Regelvorsignal (S9) zu erhalten, wobei insbesondere die Digitalisierung auch im Signalpfad vor der Filterung durch den ersten Filter (F1) erfolgen kann;
• 15. Filterung und/oder Verzögerung des digitalen Regelvorsignals (S9), insbesondere in einem digitalen Filter (FF), zu dem besagten Regelsignal (S4),
  • a. wobei das digitale Filter mit dem ersten Taktsignal (clk1) oder dem komplementären ersten Taktsignal (clk1q) synchronisiert ist und
  • b. wobei insbesondere das digitale Filter (FF) eine Einheit mit dem Analog-zu-Digital-Wandler (ADC) und/oder bei digitaler Realisierung des ersten Filters (F1) mit diesem ersten Filter (F1) eine Einheit bilden kann;
• 16. Ausgabe des Regelsignals (S4) als Messwertsignal für die Eigenschaften zumindest einer der optischen Übertragungsstrecken und/oder zumindest eines der Objekte (O, O2) innerhalb zumindest einer der optischen Übertragungsstrecken (11, 12, 13, 14).

The following typical steps are mentioned here:

• 13. Filtering - especially low-pass filtering and / or integration - of the mixed signal ( S7 ), especially in a first filter ( F1 ), to create a control signal ( S8 );
• 14.Analog-to-digital conversion of the control signal ( S8 ) to a digitized control signal ( S9 ), especially in an analog-to-digital converter ( ADC ) to generate a digital pilot signal ( S9 ), whereby in particular the digitization also in the signal path before the filtering by the first filter ( F1 ) can be done;
• 15.Filtering and / or delaying the digital pre-control signal ( S9 ), especially in a digital filter ( FF ), to the said control signal ( S4 ),
  • a. where the digital filter with the first clock signal ( clk1 ) or the complementary first clock signal ( clk1q ) is synchronized and
  • b. where in particular the digital filter ( FF ) a unit with the analog-to-digital converter ( ADC ) and / or with digital implementation of the first filter ( F1 ) with this first filter ( F1 ) can form a unit;
• 16. Output of the control signal ( S4 ) as a measured value signal for the properties of at least one of the optical transmission links and / or at least one of the objects ( O , O2 ) within at least one of the optical transmission links ( 11 , 12th , 13th , 14th ).

Use of band-limited clock signals ( clk1 × clk2 , c lk1q × clk2q , clk1 × clk2 ) has the advantage that, for example, band-limited random signals can be used instead of monofrequency signals. These can be used for code spreading. For this purpose, please refer to the EP 2 817 657 B1 which covers the use of band-limited broadcast signals. In this disclosure, a particularly simple variant of the method of EP 2 817 657 B1 treated, which is made possible by a very special form of the transmission signal and compared to the method of EP 2 817 657 B1 is considerably simplified. the EP 2 817 657 B1 applies the boundary conditions disclosed here to the band-limited clock signal ( clkl × clk2 ) and the complementary band-limited clock signal ( clklq × clk2q ) and the first band-limited clock signal ( clkl × clk2 ) and the second band-limited clock signal ( clklq × clk2 ) not open.

The method corresponds to a corresponding device for measuring the properties of at least one electromagnetic transmission path ( l1 , l2 , l3 , l4 ) and / or at least one object ( O , O2 ) within at least one electromagnetic or optical transmission path ( l1 , l2 , l3 , l4 ) for use during an observation period. It has a first clock generator ( G ), which has a first clock signal ( clk1 ) with a first clock period ( T ₁ ) and a second clock signal ( clk2 ) with a second clock period ( T ₂ ) generated. The second clock period ( T ₂ ) is shorter than the first clock period ( T ₁ ). The second clock period preferably corresponds to ( T ₂ ) of the first clock period ( T ₁ ) divided by an integer greater than 1. The clock generator ( G ) can, for example, from a first clock generator ( G1 ) and a second clock generator ( G2 ) exist. In addition to these signals, the clock generator ( G ) also a to the first clock signal ( clk1 ) complementary first clock signal ( clk1q ) and in case II ( 3 ) in addition to the second clock signal ( clk2 ) complementary second clock signal ( clk2q ). The clock generator ( G ) a band-limited clock signal ( clk1 × clk2 ) and a complementary band-limited clock signal ( clk1q × clk2q ) or a first band-limited clock signal ( clk1 × clk2 ) and a second band-limited clock signal ( clk1q × ckl2 ) to use the more general methods described above.

The device further comprises a first mixer ( Wed1 ), for example consisting of a fifth and third multiplier ( M5 , M3 ), which is the first clock signal ( clk1 ) and the second clock signal ( clk2 ) and the control signal ( S4 ) to the compensation distant signal ( S3v ) mixes with each other, i.e. preferably multiplied here, or the band-limited clock signal ( clkl × clk2 ) with the control signal ( S4 ) to the compensation distant signal ( S3v ) mixes, in this case preferably multiplied.

The device further comprises a second mixer ( Wed2 ), for example consisting of a fourth and a sixth multiplier ( M4 , M6 ), which in case I ( 4th ) the complementary first Clock signal ( clk1q ) and the complementary second clock signal ( clk2q ) and the control signal ( S4 ) to the pre-send signal ( S5v ) mixes with each other, here preferably multiplied, or also in case I ( 4th ) the complementary band-limited clock signal ( clk1q × clk2q ) or the first band-limited clock signal ( clk1q × clk2q ) with the control signal ( S4 ) to the pre-send signal ( S5v ) mixes, in this case preferably multiplied. In case II ( 3 ) this mixer has been modified to take account of the problem that it occurs in the negative half-waves (0 phases) of the second clock signal ( clk2 ) would lead to extinctions. Therefore the second mixer mixes ( Wed2 ) then only the complementary first clock signal ( clk1q ) and the second clock signal ( clk2 ) and the complementary control signal ( S4q ) to the pre-send signal ( S5v ) together. This is also preferably a multiplication. Alternatively, in this case II, the second mixer ( Wed2 ) the second band-limited clock signal ( clk1q × clk2 ) with the control signal ( S4 ) to the pre-send signal ( S5v ) mix, so preferably multiply here.

These mixers and signal generators can of course be implemented as a functional unit with the same effect and different architecture. For example, it is common practice to implement multiplications and thus the multipliers using switches. This is particularly advantageous when, for example, the signals are processed differentially in the receive path.

One version of the proposed device has a transmitter ( H ), which has a modulated electromagnetic transmission signal ( S5i ) into the first transmission path ( 11 ), whereby the signal intensity (signal energy) of this modulated electromagnetic transmission signal ( S5i ) with the pre-send signal ( S5v ) correlated in such a way that at least parts of the emitted modulated electromagnetic transmission signal ( S5i ) in an observation period that includes several pulses of the transmission pre-signal ( S5v ), proportional to the pre-transmit signal ( S5 ) are. It assigns a compensation transmitter ( K ), which is an electromagnetic modulated compensation signal ( S3i ) into the third transmission path ( 13th ), whereby the signal intensity (signal energy) of this modulated compensation signal ( S3i ) with the compensation pre-signal ( S3v ) correlated in such a way that at least parts of the emitted electromagnetic modulated compensation signal ( S3i ) in an observation period that contains several pulses of the compensation pre-signal ( S3v ), proportional to the compensation signal ( S3v ) are.

The electromagnetic modulated transmission signal ( S5i ) and / or the electromagnetic modulated compensation signal ( S3i ) is applied to at least one object ( O , O2 ) in at least one transmission link ( 11 , 12th , 13th , 14th ) reflected and / or by at least one object ( O , O2 ) transmitted. The object then feeds ( O ) the modulated electromagnetic transmission signal ( S5i ) as a modified electromagnetic transmission signal ( S5s ) into a second transmission path ( 12th ) on. The second object ( O2 ) then the electromagnetic modulated compensation signal ( S3i ) as a modified electromagnetic compensation signal ( S3s ) into a fourth transmission path ( 14th ) feed in, with one or more transmission links ( 11 , 12th , 13th , 14th ) with the respective object ( O , O2 ) can be identical. A recipient ( D. ) receives the modified electromagnetic compensation signal ( S3s ) of the compensation transmitter ( K ) after exiting the third and / or fourth transmission path ( 13th , 14th ) and after going through at least one of these. The reception is cumulatively superimposed and / or multiplied superimposed on the modified electromagnetic transmission signal ( S5s ) of the sender ( H ). Recipient ( D. ) also receives the modified electromagnetic transmission signal ( S5s ) of the sender ( H ) after exiting the first and / or second transmission path ( 11 , 12th ) and after going through at least one of these. Recipient ( D. ) generates a receiver output signal ( S0 ) depending on the received superimposition of the modified transmission signal ( S5s ) and the compensation transmission signal ( S3s ).

It preferably has a third mixer ( Wed3 ) on. This preferably consists of a first multiplier ( M1 ) and a second multiplier ( M2 ).

The third mixer ( Wed3 ) multiplied in case I ( 4th ) the second clock signal ( clk2 ) with the complementary first clock signal ( clk1q ). This results in case I ( 4th ) as part of the demodulation, a factor of -1 is fed into the signal circuit, which leads to the stability of the control. The demodulation by the third mixer ( Wed3 ) in case I ( 4th ) is preferably carried out in such a way that the second clock signal ( clk2 ) and the complementary first clock signal ( clk1q ) or corresponding signals with the same effect derived therefrom (e.g. digitized or phase-shifted clock signals) with the receiver output signal ( S0 ) or one from the receiver output signal ( S0 ) derived signal, in particular a filtered receiver output signal ( S1 ) or an amplified receiver output signal ( S2 ), to a first mixed signal ( S7 ) are multiplied.

The third mixer ( Wed3 ) multiplied in case II ( 3 ) the second clock signal ( clk2 ) with the first clock signal multiplied by - 1 ( clk1 ). This results in case II ( 3 ) as part of the demodulation, a factor of -1 is fed into the signal circuit, which leads to the stability of the control. The demodulation by the third mixer ( Wed3 ) in case II ( 3 ) is preferably carried out in such a way that the second clock signal ( clk2 ) and the first clock signal multiplied by -1 ( clk1 ) or corresponding signals with the same effect derived therefrom (e.g. digitized or phase-shifted clock signals) with the receiver output signal ( S0 ) or one from the receiver output signal ( S0 ) derived signal, in particular a filtered receiver output signal ( S1 ) or an amplified receiver output signal ( S2 ), to a first mixed signal ( S7 ) are multiplied.

The second multiplier ( M2 ) and the first multiplier ( M1 ) can therefore in their function all or part of it through a single dividing device - the third mixer ( Wed3 ) - are replaced, the parts of these functions are replaced with the same function. It is essential that the demodulation is carried out by mixing the two clock signals ( clk1 , clk2 ) or by mixing with signals derived therefrom, for example by multiplying by -1 or inversion, in each case in such a way that the same purpose of demodulation takes place without cancellation by zero levels.

The device has a preferably analog first filter ( F1 ), which can in particular be a low-pass filter and / or an integrator, and which the first mixed signal ( S7 ) and / or a signal derived therefrom for a pre-control signal ( S8 ) filters. The first filter ( F1 ) an upper filter cut-off frequency ω _fo to below half the lower limit frequency in some applications ω _u of the band-limited clock signal ( clkl × clk2 ) or the first band-limited clock signal ( clk1 × clk2 ) should be. The device has an analog-to-digital converter ( ADC ), which the control signal ( S8 ) to a digitized control signal ( S9 ) converts, whereby the digitization is carried out by the analog-to-digital converter ( ADC ) also before filtering through the first filter ( F1 ) can take place, but experience has shown that this is less favorable. This digitized control signal ( S9 ) is now in a digitized loop filter (the filter FF ) further treated. The proposed device thus has a digital filter ( FF ), which according to the proposal disclosed here with the first clock signal ( clk1 ) is synchronized. This synchronization is essential to the invention and ensures that the two clock signals ( clk1 , clk2 ) are always orthogonal with regard to the scalar product implemented in the device. This digital filter ( FF ) is in the case of a one-bit-wide digital control pre-signal ( S9 ) the output of the analog-to-digital converter ( ADC ). This digital filter ( FF ) is particularly preferred only a flip-flop ( FF ). The digital filter ( FF ) filters the digital pilot signal ( S9 ) to the control signal ( S4 ) and / or delays this. If the digital pilot signal ( S9 ) is a digital signal with a bit width of more than one bit, e.g. n bits with n> 1, the control signal ( S4 ) preferably converted back into an analog signal before being fed back into the device. The figures only show the case of a one-bit digital control advance signal ( S9 ). Such a control signal converted back into analog ( S4 ) with n-bit width would then instead of the control signal ( S4 ) the input signal for the first mixer ( Wed1 ) and the second mixer ( Wed2 ) instead of the drawn digital control signal ( S4 ) represent. The device thus has a digital filter ( FF ), in particular a flip-flop ( FF ), and where this digital filter ( FF ) the digital pilot signal ( S9 ) to the control signal ( S4 ) filters and / or delays. The digital filter ( FF ) is used with the first clock signal ( clk1 ) or the complementary first clock signal ( clklq ) or synchronized with a synchronous and possibly phase-shifted signal. It is particularly preferred to be one with the first clock signal ( clk1 ) synchronized flip-flop ( FF ). The device emits the control signal ( S4 ) as a measured value signal for properties of at least one optical transmission measurement path ( 11 , 12th , 13th , 14th ) and / or as a measured value of the property of at least one object ( O , O2 ) within one or more optical transmission measuring sections ( 11 , 12th , 13th , 14th ) from or to other parts of the device for further processing.

• • die optische Transparenz einer Übertragungsstrecke,
• • der optische Brechungsindex in einer Übertragungsstrecke,
• • die optische Streuung in einer Übertragungsstrecke,
• • die Reflexion an einer Grenzfläche in der Übertragungsstrecke - insbesondere an der Wand einer Glasfaser,
• • spektrale Eigenschaften einer Übertragungsstrecke bei Verwendung von LEDs mit unterschiedlicher Wellenlänge
• • Reflektivität eines Objekts
• • Abstand eines Objekts
• • Polarisationseigenschaften einer Übertragungstrecke oder der Oberfläche eines Objekts
• • Reflexionseigenschaften der Oberfläche eines Objekts
• • Oberflächenform eines Objekts
• • Vorhandensein eines Objekts
• • Aerosoleigenschaften eines wolkenförmigen Objekts, wie beispielsweise Rauch, Nebel oder Regen
• • etc.

Such properties that can be represented by the measured value can, for example, not only be:

• • the optical transparency of a transmission path,
• • the optical refractive index in a transmission path,
• • the optical scattering in a transmission link,
• • the reflection at an interface in the transmission path - especially on the wall of a glass fiber,
• • Spectral properties of a transmission path when using LEDs with different wavelengths
• • Reflectivity of an object
• • Distance of an object
• • Polarization properties of a transmission path or the surface of an object
• • Reflective properties of the surface of an object
• • Surface shape of an object
• • Presence of an object
• • Aerosol properties of a cloud-shaped object, such as smoke, fog or rain
• • Etc.

Figure list

• 1 1 shows schematically the device principle according to FIG EP 2 602 635 B1 from the state of the art.
• 2 2 shows schematically the device principle according to FIG DE 10 2015 006 174 B3 from the state of the art.
• 3 3 shows, by way of example, schematically the device principle corresponding to the proposed device for case II of the use of asymmetrical clock signal levels between 0 and 1, for example.
• 4th 3 shows, by way of example, schematically the device principle corresponding to the proposed device for the case I of the use of clock signal levels symmetrical to zero, for example between -1 and 1.
• 5 5 shows the signals according to EP 2 602 635 B1 . (State of the art).
• 6th 6th shows the signals according to the proposed device for case II.
• 7th 7th shows the frequency response according to an exemplary implementation EP 2 602 635 B1 without a high pass filter.
• 8th 8th shows the frequency response according to an exemplary implementation EP 2 602 635 B1 as the corresponding peak-to-peak value.
• 9 9 shows the corresponding peak-to-peak value of the frequency response according to an exemplary implementation EP 2 602 635 B1 with double-logarithmic scaling (in dB).

The figures are explained in the text above.

glossary

Mix

In the context of this disclosure, the mixing of two signals is preferably understood to mean the multiplication of two signals. This can be done analog or digital. In the case of digital multiplication, two value systems are possible. For the first (case I) one level can be evaluated as -1 and the other level as +1. In that case an XOR gate can be used as a multiplier. Secondly (case II) one level can be evaluated as 0 and the other level as 1. In this case, a multiplication by means of a simple AND gate is possible for two one-bit-wide signals. The use of switches etc. is also conceivable. Furthermore, multiplying amplifiers, etc. can be used. Theoretically, the use of non-linear mixers is also possible, but this is not recommended.

Corresponding to amplitudes

The first amplitude of a signal at a first frequency ω ₁ In terms of magnitude, then corresponds to the second amplitude of a possibly different signal at a second frequency ω ₂ if the magnitude of the first and second amplitude does not differ from one another by more than 10% of the measured amplitude value.

Observation period

In the context of this disclosure, an observation period is understood to mean a period of time which comprises several successive clock periods of the first clock signal ( clk1 ) includes.

Complementary

For the purposes of this disclosure, a first signal S ₁ (t) is complementary to a second signal S ₂ (t) if the following applies to the amplitudes of these two signals at a point in time t: $${\text{S.}}_{\text{2}}\left(\text{t}\right)=\text{a}\ast {\text{S.}}_{\text{1}}\left(\text{t}\right)+\text{O and a}<0$$

The second signal is therefore an affine mapping of the first signal with an offset O. In the case of a digital signal S ₁ (t), the inverted signal is therefore a complementary signal. Smaller time delays due to the throughput time through the amplifier or inverter are negligible if this phase relationship is fixed.

List of reference symbols

A1

Adder;

ADC

Comparator or analog-to-digital converter;

BP

Filter, which is preferably a band pass filter;

clk1

first clock signal;

clk1q

complementary first clock signal. The complementary first clock signal is preferably derived from the first clock signal ( clk1 ) generated by inversion or gain with a negative gain;

clk1 × clk2

bandwidth-limited clock signal (case I) or first bandwidth-limited clock signal (case II). The bandwidth-limited clock signal or the first is particularly preferred bandwidth-limited clock signal the product of a first clock signal ( clk1 ) and a second clock signal ( clk2 ). Other bandwidth-limited clock signals are conceivable;

clk1q × clk2

second bandwidth-limited complementary clock signal in case II. The second bandwidth-limited clock signal preferably represents the product of a complementary first clock signal ( clklq ) and a second clock signal ( clk2 ) represent;

clk1q × clk2q

bandwidth-limited complementary clock signal in case I. The bandwidth-limited complementary clock signal is preferably composed of the bandwidth-limited clock signal ( clk1 × clk2 ) generated by inversion or gain with a negative gain;

clk2

second clock signal;

clk2q

complementary second clock signal. The complementary second clock signal is preferably derived from the second clock signal ( clk2 ) generated by inversion or gain with a negative gain;

CT

Regulator;

D.

Recipient;

Δω

Bandwidth of the bandwidth-limited clock signal ( clk1 × clk2 ) and the complementary bandwidth-limited clock signal ( clklq × clk2q ) (Case I) or the first bandwidth-limited clock signal ( clkl × clk2 ) and the second bandwidth-limited clock signal ( clk1q × clk2 ) (Case II)

F1

first filter;

FF

Delay stage. The delay stage is preferably implemented as a clocked register or as a flip-flop;

G

Clock generator;

G1

first clock generator;

G2

second clock generator;

H

Channel;

11

first transmission link;

12th

second transmission link;

13th

third transmission link;

14th

fourth transmission path;

INV1

first inverter;

INV2

second inverter;

INV3

third inverter;

INV4

fourth inverter;

K

Compensation transmitter;

LR

Reference value transmitter;

M1

first multiplier;

M2

second multiplier;

M3

third multiplier;

M4

fourth multiplier;

M5

fifth multiplier;

M6

sixth multiplier;

Wed1

first mixer, for example, consisting of the fifth multiplier ( M5 ) and the third multiplier ( M3 );

Wed2

second mixer, for example, consisting of the fourth multiplier ( M4 ) and the sixth multiplier ( M6 );

Wed3

third mixer, for example, consisting of the first multiplier ( M1 ) and the second multiplier ( M2 );

N1 (ω)

normalized amplitude frequency spectrum of the first clock signal ( clk1 )

N2 (ω)

normalized amplitude frequency spectrum of the second clock signal ( clk2 )

N3 (ω)

normalized amplitude frequency spectrum of the complementary first clock signal ( clk1q )

N4 (ω)

normalized amplitude frequency spectrum of the complementary second clock signal ( clk2q )

O

first object;

O2

second object;

ω1

first frequency;

ω2

second frequency;

ωfo

upper filter cut-off frequency of the first filter ( F1 );

ωu

lower limit frequency of the bandwidth-limited clock signal ( clk1 × clk2 ) and the complementary bandwidth-limited clock signal ( clk1q × clk2q ) (Case I) or the first bandwidth-limited clock signal ( clkl × clk2 ) and the second bandwidth-limited clock signal ( clk1q × clk2 ) (Case II);

ωm

Center frequency of the bandwidth-limited clock signal ( clk1 × clk2 ) and the complementary bandwidth-limited clock signal ( clk1q × clk2q ) (Case I) or the first bandwidth-limited clock signal ( clkl × clk2 ) and the second bandwidth-limited clock signal ( clklq × clk2 ) (Case II);

ωo

Upper limit frequency of the bandwidth-limited clock signal ( clk1 × clk2 ) and the complementary bandwidth-limited clock signal ( clk1q × clk2q ) (Case I) or the first bandwidth-limited clock signal ( clk1 × clk2 ) and the second bandwidth-limited clock signal ( clk1q × clk2 ) (Case II);

50

Receiver output signal of the receiver ( D. );

S1

filtered receiver output signal;

S2

amplified receiver output signal;

S3

Compensation signal;

S3i

modulated compensation signal that the compensation transmitter ( K ) into the third transmission path ( l3 ) and that with the compensation signal ( S3 ) correlated;

S5s

modified electromagnetic compensation signal that the second object ( O2 ) based on the modulated compensation signal ( S3i ) into the fourth transmission path ( l4 ) feeds;

S3v

Compensation pre-signal;

S4

Control signal that also represents the measured value;

S4i

Sign signal;

S4q

complementary control signal that also represents the measured value;

S5

Transmit signal;

S50

Base transmission signal of the EP 2 602 635 B1

S5d

deformed transmission signal;

S5i

modulated electromagnetic transmission signal that the transmitter ( H ) into the first transmission path ( l1 ) feeds;

S5s

modified electromagnetic transmission signal that the object ( O ) based on the modulated electromagnetic transmission signal ( S5i ) into the second transmission path ( l2 ) feeds;

S5v

Send pre-signal;

S6

first mixed signal;

S7

Mixed signal;

S8

Control signal;

S9

digital pre-signal;

S50

Base broadcast signal;

SR

incident interference signal;

SW1

first switch;

SW2

second switch;

T1

first clock period of the first clock signal ( clk1 ) or the complementary first clock signal ( clk1q );

T2

second clock period of the second clock signal ( clk2 ) or the complementary second clock signal ( clk2q );

V1

first amplifier;

V2

second amplifier;

V3

third amplifier;

VG

Sign generator;

vref2

Reference value;

List of the cited writings

• DE 4 339 574 C2 ,
• DE 4 411 770 A1
• DE 4 411 773 C2 ,
• DE 10 2005 045 993 B4 ,
• DE 10 2014 002 194 A1 ,
• DE 10 2014 002 486 A1 ,
• DE 10 2014 002 788 A1 ,
• DE 10 2015 006 174 B3 ,
• EP 8 017 26 B1 ,
• EP 1 258 084 B1 ,
• EP 1 269 629 B1 ,
• EP 1410 507 B1 ,
• EP 1435 509 B1 ,
• EP 1480 015 A1 ,
• EP 1 671 160 B1 ,
• EP 1 723 446 B1 ,
• EP 1 747 484 B1 ,
• EP 1 901 947 B1 ,
• EP 2 016 480 B1 ,
• DE 10 2008 016 938 B3 ,
• EP 2 405 283 B1 ,
• EP 2 594 023 B1 ,
• EP 2 598 908 B1 ,
• EP 2 602 635 B1 ,
• EP 2 653 885 A1 ,
• EP 2 679 982 A1 ,
• EP 2 817 657 B1 ,
• US 2012 0 326 958 A1 ,
• WO 2013 037 465 A1 ,
• WO 2013 076 079 A1 ,
• WO 2013 083 346 A1 ,
• WO 2013 113 456 A1 ,
• WO 2013 156 557 A1 ,
• WO 2014 096 385 A1 .

Claims (2)

Method for measuring the properties of at least one electromagnetic transmission path and / or an object (O) within at least one electromagnetic transmission path (11, 12, 13, 14) for use during an observation period with the following steps: - Generating a first clock signal (clk1) with a first clock period (T ₁ ) and a complementary first clock signal (clk1q); - Generating a second clock signal (clk2) with a second clock period (T ₂ ) which is shorter than the first clock period (T ₁ ), and a second clock signal (clk2q) complementary thereto; - Mixing the first clock signal (clk1) and the second clock signal (clk2) with a control signal (S4) to form a compensation pre-signal (S3v); - Mixing the complementary first clock (clk1q) and the complementary second clock signal (clk2q) with the control signal (S4) to form a transmission signal (S5v); - Emission of a modulated electromagnetic transmission signal (S5i) by a transmitter (H) in the first transmission path (11), the signal intensity (signal energy) of this modulated electromagnetic transmission signal (S5i) being correlated with the transmission pre-signal (S5v) in such a way that at least components the emitted modulated electromagnetic transmission signal (S5i) are proportional to the transmission preliminary signal (S5v) in an observation period which comprises several pulses of the transmission pre-signal (S5v); - Emission of an electromagnetic modulated compensation signal (S3i) by a compensation transmitter (K) in the third transmission path (13), the signal intensity (signal energy) of this modulated compensation signal (S3i) correlates with the compensation pre-signal (S3v) in such a way that at least portions of the emitted electromagnetic modulated compensation signal (S3i) are proportional to the compensation advance signal (S3v) in an observation period which comprises several pulses of the compensation pre-signal (S3v); - One or more of the two steps • Reflection of the modulated electromagnetic transmission signal (S5i) on a first object (O) and / or transmission of the modulated electromagnetic transmission signal (S5i) through a first object (O) and subsequent feeding in of the modulated electromagnetic transmission signal (S5i) as a modified electromagnetic transmission signal (S5s) in a second transmission link (12), wherein the second transmission link (l2) and / or the first transmission link (l1) can be identical to the first object (O), and / or • reflection of the electromagnetic modulated Compensation signal (S3i) to a second object (O2) and / or transmission of the electromagnetic modulated compensation signal (S3i) through a second object (O2) and subsequent feeding of the electromagnetic modulated compensation signal (S3i) as a modified electromagnetic compensation signal (S3s) into a fourth transmission path (14), the fourth ex transmission path (l4) and / or the third transmission path (l3) can be identical to the second object (O2) and • wherein the first object (O) can also be identical to the second object (O2); - Exit of the modified electromagnetic transmission signal (S5s) of the transmitter (H) from the second transmission path (12), after passing through the same and receiving the modified electromagnetic transmission signal (S5s) by a receiver (D); - Exit of the modified electromagnetic compensation signal (S3s) of the compensation transmitter (K) from the fourth transmission path (l4) or third transmission path (l3) after passing through the corresponding transmission path (l3, l4) and receipt of the emerged modified electromagnetic compensation signal (S3s) by the Receiver (D), the reception taking place summing and / or multiplying with the modified electromagnetic transmission signal (S5s) of the transmitter (H), which has emerged from the second transmission link (l2), as reception of an overlay; - Formation of a receiver output signal (S0) by the receiver (D) as a function of the received superimposition of the modified transmission signal (S5s) that emerged from the second transmission path (l2) and the modulated signal that emerged from the fourth transmission path (l4) or third transmission path (l3) electromagnetic compensation transmission signal (S3s); - Either: • Formation of a first mixed signal (S6) by mixing the receiver output signal (S0) or a signal derived from the receiver output signal on the one hand with the second clock signal (clk2) on the other hand; • Forming a mixed signal (S7) by mixing the complementary first clock signal (clk1q) with the first mixed signal (S6); or • Forming the mixed signal (S7) by mixing the receiver output signal (S0) or a signal derived from the receiver output signal on the one hand with the second clock signal (clk2) and with the complementary first clock signal (clklq); - Filtering of the mixed signal (S7) to form a control pre-signal (S8); - Analog-to-digital conversion of the pre-control signal (S8) to a digitized control signal (S9) in order to obtain a digital pre-control signal (S9); - Filtering and / or delaying the digital control pre-signal (S9) to the said control signal (S4), the filtering and / or delaying being synchronized with the first clock signal (clk1) and / or the complementary first clock signal (clklq); - Output of the control signal (S4) or a signal derived therefrom as a measured value signal for the properties of at least one of the optical transmission links and / or at least one of the objects (O, O2) within at least one of the optical transmission links (l1, l2, l3, l4). Device for measuring the properties of at least one electromagnetic transmission path (l1, l2, l3, l4) and / or at least one object (O, O2) within at least one electromagnetic or optical transmission path (l1, l2, l3, l4) for use during an observation period - wherein it has a clock generator (G), • which generates a first clock signal (clk1) with a first clock period (T ₁ ) and a first clock signal (clk1q) complementary to the first clock signal (clk1) and • which generates a second clock signal (clk2 ) with a second clock period (T ₂ ) and a second clock signal (clk2q) which is complementary to the second clock signal (clk2), • where the second clock period (T ₂ ) is shorter than the first clock period (T ₁ ), and either has a fifth and third multiplier (M5, M3), • which the first clock signal (clk1) and the second clock signal (clk2) multiply with a control signal (S4) to form a compensation pre-signal (S3v) and • which can be designed as a functional unit with the same effect, or alternatively it has a first mixer (Mi1), • which the first clock signal (clkl) and the second clock signal (clk2) mixes with a control signal (S4) to form a compensation pre-signal (S3v), and - having either a fourth and a sixth multiplier (M4, M6), • which the complementary first clock signal (clk1q) and the complementary second clock signal (clk2q ) multiply with a control signal (S4) to form a pre-transmit signal (S5v) and • which can be designed as a functional unit with the same effect or which has a second mixer (Mi2), • which has the complementary first clock signal (clklq) and the complementary second Mixes clock signal (clk2q) with a control signal (S4) to form a pre-transmit signal (S5v), and - having a transmitter (H) which emits a modulated electromagnetic transmission signals (S5i) into the first transmission path (l1), the signal intensity (signal energy) of this modulated electromagnetic transmission signal (S5i) correlates with the transmission pre-signal (S5v) in such a way that at least components of the emitted modulated electromagnetic transmission signal (S5i) are in a Observation period, which comprises several pulses of the pre-transmission signal (S5v), are proportional to the pre-transmission signal (S5v) and - it has a compensation transmitter (K) which sends an electromagnetic modulated compensation signal (S3i) into the third transmission path (l3), the signal intensity (Signal energy) of this modulated compensation signal (S3i) is correlated with the compensation pre-signal (S3v) in such a way that at least parts of the emitted electromagnetic modulated compensation signal (S3i) are proportional to the compensation pre-signal (S3i) in an observation period that comprises several pulses of the compensation pre-signal (S3v) v) are; - the electromagnetic modulated transmission signal (S5i) and / or the electromagnetic modulated compensation signal (S3i) being reflected on at least one object (O, O2) in at least one transmission path (11, 12, 13, 14) and / or by at least one object ( O, O2) is transmitted and that the object (O) then feeds the modulated electromagnetic transmission signal (S5i) as a modified electromagnetic transmission signal (S5s) into a second transmission path (l2) and / or that the second object (O2) then modulates the electromagnetic Compensation signal (S3i) fed as a modified electromagnetic compensation signal (S3s) into a fourth transmission link (l4), one or more transmission links (11, 12, 13, 14) being identical to the respective object (O, O2), and - wherein a receiver (D) the modified electromagnetic compensation signal (S3s) of the compensation transmitter (K) after exiting the third and / or vie rth transmission path (13, 14) and, after passing through at least one of these, receives the reception adding and / or multiplying with the modified electromagnetic transmission signal (S5s) of the transmitter (H), and - the receiver (D) receiving the modified electromagnetic transmission signal (S5s) of the transmitter (H) after exiting the first and / or second transmission path (11, 12) and after passing through at least one of these, and - the receiver (D) receiving a receiver output signal (S0) as a function generated by the received superimposition of the modified transmission signal (S5s) and the compensation transmission signal (S3s) and - either as case α • has a first multiplier (M1), • which generates the first mixed signal (S6) by generating the receiver output signal (S0 ) or a signal derived from the receiver output signal (S0) is multiplied on the one hand by the second clock signal (clk2) on the other hand, and a second multip has lizierer (M2), • which multiplies the first mixed signal (S6) with the complementary first clock signal (clk1) to the mixed signal (S7), and • wherein the function of the second multiplier (M2) and the first multiplier (M1) are all or can be partially replaced by a single sub-device that replaces parts of these functions with the same function, - or where, as an alternative to case α, it has a third mixer (Mi3) as case β, • which generates the receiver output signal (S0) or one from the receiver output signal (S0 ) mixes the derived signal on the one hand with the second clock signal (clk2) and the complementary first clock signal (clk1) to form the mixed signal (S7), and - having a first filter (F1) which the first mixed signal (S7) and / or one of it filters derived signal to form a pre-control signal (S8) and - wherein it has an analog-to-digital converter (ADC) which converts the pre-control signal (S8) to a digitized control signal (S9), d The digitization by the analog-to-digital converter (ADC) can also take place before filtering by the first filter (F1), and - with a digital filter (FF) and with this digital filter (FF) the digital control signal (S9) filters and / or delays the control signal (S4) and - wherein the device uses the control signal (S4) as a measured value signal for properties of at least one optical transmission measurement path (11, 12, 13, 14) and / or at least one object (O, O2) within one or more optical transmission measurement paths (11, 12, 13, 14) or forwards it to other parts of the device for further processing.

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