DE1266366B - Radio location receiver with digital display - Google Patents

Description

Radio Location Receiver With Digital Display The invention relates to on a radio location receiver for measuring a relative position of objects in which the measured variable is present in the form of the mechanical position of a resolver and through Measurement of the electrical phase difference between the comparison oscillation fed to the resolver and the vibration emitted by it is determined and in which the vibrations to increase the measurement accuracy frequency-multiplied and the phase difference converted into electrical digital values and displayed in the form of numbers It is known to take measurements of the distance and / or direction between attract two distant sfations or objects by using electromagnetic waves constant frequency as transmission or Serve as the reference signal, while the (e.g. after Reflection again) received waves have a relative phase shift, which is proportional to the distance or direction to be measured. The phase difference between the reference signal and the received signal is determined by a phase detector circuit measured, the display of which is proportional to the electrical phase difference. the However, practice has shown that such systems, from the theoretical point of view should work well, have insufficient accuracy and a fine subdivision of the distance or the angle of rotation on z. B. 1/100 000 or no more possible because of changes in the waveform and asymmetrical structure of the circuits leads to an output signal of insufficient accuracy, the not sufficient for many tasks. Measuring arrangements for determining phase shifts are generally known state of the art (for example from German patent specification 661924). It is also known to measure the phase difference between two AC voltages to multiply the phase angle by frequency multiplication and thus the Measuring. increase accuracy pa. Finally, there is also a low frequency phase meter became known, the digital angle display with a 360-fold frequency multiplication in degrees enabled ()> Electronic Engineeringa, January -1959, pp. 13 to 15).

The problem of a multi-digit numerical phase difference display In the case of high-frequency waves with high A, resolution accuracy, as is the case with radio location required, but has not been resolved here.

A location receiver of the type mentioned at the beginning for determination the distance and / or direction of objects is characterized according to the invention, that to carry out a multiple digit numerical display of the phase difference special number display channels are provided for each digit, in those for the numbers after the first digit represent the measurement oscillation from the previous channel multiplied by n and with the (ni1) -fold comparison oscillation is mixed, where n is the base of the number system used, and then together with the comparison oscillation to a phase meter known per se Display of the respective digits are fed.

The location receiver according to the invention has novel phase measurement methods operated with one or more different types of resolvers to achieve a satisfactory solution to the above problem.

The electrical phase delay caused by the decomposer becomes transmitted in different electrical signal channels, where the electrical phase angle is multiplied by a different factor in each channel. Any channel is provided with a phase detector, and the DC signal from each phase detector in each channel is fed to a display device which has a multi-digit number display In this way, each phase detector need not provide the 360 "of the sine wave subdivide more parts than the basis of the counting system used, which are explained in the Embodiment the number 10 is.

The output signal obtained from the phase detectors can be different Kinds may be applied to provide a visual indication of the location size or to operate a control device.

The use of an electron beam type counting tube enables the direct display of the distance.

There is a self-synchronization between the supplied ones in the system analog mechanical values and the output electrical digital values, without that this is done electronically.

The digital display is represented by the electrical phase difference between the transmission and reception waves determined, and the display does not change if the device is put back into operation after being switched off.

The resolver preferably has a multiplicity of pole pairs for division the phase shift of the comparison oscillation from 0 to 360 ° and gives the A phase-shifted oscillation with respect to the comparison oscillation, if necessary, to one Amplifier off.

The resolver can be pivoted from 0 to 360 ° by means of rotating devices Have pole pair, around which along the circumference of a circle the plurality of Pole pairs is arranged, which emit the phase-shifted oscillation. Here can the output signal emitted by the pivotable pair of poles as an input signal to the pole pairs arranged around the pivotable pole pair.

The invention provides an improved location system for accurate Measurement of an object in space with regard to its distance and / or its direction or its angle. For this purpose, the subject matter of the invention is the specification of a phase expansion system for an accurate indication of the electrical phase shift, which is in numerical or digital form enables the exact display of the location size of the object in space. The invention ~ achieves a selective phase expansion of the signals in different Channels, with each channel having a single digit of the multi-digit measurement result is assigned and a resolver or divider is used, the different Has gains and combines the output signals to produce a rough digital display to deliver. Another detail of the invention is that the disassembler provides two output signals, one of which is the most important as the rough output signal Part of a multi-digit number element supplies, while-the fine or smaller output signal results in the less important part of a multi-digit number, whereby a phase expansion system is to be used for both output signals of the splitter.

Ultimately, the invention provides a phase stretching system that is capable of is a spacing unit, e.g. B. 2.5 cm, divided into 10,000 or more parts, with only an accuracy of the divider system of about the square root of one Ten thousandths of a unit of length is required.

The invention is hereinafter based on the description and the Drawings explained in more detail.

Fig. 1 is a block diagram of a phase expansion circuit; F i G. 2 is a schematic drawing of the electrical windings of one form of the Decomposer that can be used in the system according to the invention; F i -g. 3 Figure 3 is a circuit diagram of a phase detector circuit; that in the system according to the invention can be applied; F i g. 4 is a diagram of a counter tube used in the system according to the invention can be applied; F i g. 5 shows a block diagram, which illustrates an arrangement for coarse digital display; F i g. 6 shows a block diagram a preferred embodiment of the entire system.

A complete system according to the invention has a number of Components, each being physically different and in different ways Form- can be created by the conditions or type of to be resolved Location size, e.g. B. the distance, the desired decomposition or

Degree of division, the required response speed, the shape of the required output signal and the operating conditions.

The following are used to explain some of the terms specified here Definitions given: Accuracy: the degree of accuracy; This expression must be distinguished from »precision«, which refers to the degree of reproducibility and accuracy versus true value "digital device: a device. the one dimensional quantity into a finite number group by combination or Limit divides; Pole pair: two neighboring areas of pronounced river intensity, which have exactly the same strength but opposite polarity decomposers (Resolver): a device for both transmitting and dividing a Vector size in parts; # Resolution: a measure of the smallness of an angular or Linear distance that can just be determined; -Real-time operation: on Term used to describe the speed of a data processing process serves,; where this speed equals the formation speed of the main data which coincide in time in practice.

A system that uses the basic principles - according to the invention, is shown in Fig. 1 and shows a decomposer 20, an oscillator 22 and a phase detector 24. The decomposer 20 can be of any suitable known type. Such disassemblers include electrical conductors both on a fixed one and on a fixed one on a movable element which are inductively and / or capacitively coupled, The Oscillator 22, which supplies electrical signals of constant frequency and amplitude, is connected to an input conductor on the decomposer 20. Hieryon becomes an output signal the same but with a phase shift of less than the amount obtained, is the proportional dim mechanical entrance angle of the decomposer.

The output signal coming from the decomposer20 becomes a phase discriminator or detector 24 supplied together with the reference signal from the oscillator 22. Der Amplifier 26 then supplies appropriate signal amplitude to detector 24.

A static equilibrium current output is d from the phase detector 24 won. The size of this signal is proportional to the phase difference between the two input signals fed to the detector 24 'and the numerical tanxingorching is used 28 supplied. The high accuracy in any system that measures phase shift, required that the sine curves atgset very little distortion.

The difficulties encountered in the construction tih the electrical operation of the various switching elements used allow the possibility a division of the output signals emitted by a single phase detector in z. B. 100 000 equal - Parts hardly seem feasible. the extremely high resolution accuracy according to the present invention is achieved by Phase expansion or multiplication of phase angle based on generation of harmonics obtained by non-linear devices.

When modulating a signal of the form sin (wt +0) by means of a non-linear device or a frequency multiplier 30 according to FIG. 1 receives by solving sin n (wt +0) the nth harmonic if the output current is represented by a Taylor series expansion. This results in an expression which contains a constant coefficient and sin n (wt + #).

Since sin n (wt + #) equals sin (nwt + n #) and # is the phase difference between the output of the decomposer 20 and the reference signal from the oscillator 22, the mixing of the n-th harmonic with the (n + 1) -th harmonic results to a signal that has a component sin (wt + n #). This component off the signals of the multipliers 30 and 32 is from the mixer 34 to the detector 36 and the digital device 38, whereby the second most important digit of the Ad is received.

Another multiplication of the output signal of the mixer 34, which is in the form sin (wt + n #), with the same factor n leads to a Signal represented by sin (nwt + n2 #).

By mixing this signal with that from the frequency multiplier 32 output signal, the input signal for the phase detector 44 is equal to sin (wt + n2 #). The signal emitted by the phase detector 44 is used to direct the digital signal or meter display 46 and is proportional to the third most important digit the display.

Different types of decomposers for angle and distance measurement can be used in this location system are used, such as goniometers, transducers (»Selsyn«), measuring lines and various printed circuits with a stationary and a movable part. Each decomposer can be designed to give a signal sin (wt +0), where 0 is proportional to the displacement of the movable element. This becomes clear in the case of slotted, balanced test leads that have no standing waves.

The phase of the signal emitted by the moving sample from the sliced Line is removed is compared with the phase at a fixed point. Other Decomposition forms used the general relationship sin (x y) = sin x cos y - cos x sin y. Such a dismantling system is known.

Another type of dismantling that is able to produce a mechanical To resolve the angle of rotation accordingly is shown in FIG. 2 shown. This carver consists of a drive component, which is usually stationary, and one movable or rotatable sensing component. The drive component consists of two continuous electrical lines 51 and 52 that are geometrically in the same Plane lie on a circular orbit, the distance of which from the center is periodic fluctuates around a constant radius.

The conductors 51 and 52 have the same period and waveform. Of the Conductor 51 is shifted a quarter period with respect to conductor 52; H. offset by 90 ° phase angle. The radii of the conductors 51 and 52 can be used to avoid the overlap may be different.

If a common AC power source to the 90o phase shifting network is connected, the output of which the conductor 51 is a 90 ° phase-shifted voltage opposite to the conductor 52, then those flowing through the conductors 51 and 52 Currents at all points and at any point in time are phase-shifted over their lengths.

When a third conductor 53 of similar geometric configuration arranged with the same geometric periodicity over the conductors 51 and 52 is, so are in these conductors 53 through those in the conductors 51 and 52 flowing Alternating currents - induced voltages. The common inductances with respect to the Conductors 51 and 52 will match the position of conductor 53 with respect to conductors 51 and 52 change. The emf in conductor 53 is therefore a function of the angular or linear displacement such as the amplitudes and phases (time) of those in the conductors 51 and 52 instantaneously flowing streams.

The function by which the mutual inductance changes with the angle, can be done by choosing an appropriate geometric relationship between the conductors be determined. When the relationship between the conductor 53 (hereinafter referred to as "3a") - to conductors 51 (hereinafter referred to as> 1 ") and 52 (hereinafter referred to as> 2 ”) is chosen so that for a given position the common inductance and thus the induced emf at the phase angle 0 im im Space between conductor 3 and conductor 1 is related, the following applies: The EMF 3,1 represents the induced voltage in conductor 3 due to the in conductor 1 The EMF 3.2 is that in the conductor 3 due to the flowing in the conductor Current induced voltage EMK 3,1 = f (i1) H1 sin #, (1) EMK 3,2 = f (1H2 cos 0. (2) H1, H2 are geometry dependent constants; H1 = H2 = H because of the geometric Symmetry; = = Instantaneous current in conductor 1; i2 = instantaneous current in conductor 2.

Then EMK 3,1 + EMK 3,2 = f (i1) H sin # + f (ia) H cos #.

(3) If 11 = I1 sin wt and i2 = I2 cos wt, where I1, I2 are the amplitudes of the currents and I1 = I2 = I, then f (i1) = di1 / dt = wIcoswt, f (I2) = di2 / dt = wIsidwt.

(4) Because the induced emf is related to the rate of current change is, substituting the terms for d (il) and f (i2) gives (i2) in the equation (3) EMK 3.1 + EMK 3.2 = H wIcoswtsin # + Hwlsinwtcos0 = HwI (sinwt + 0) (5) if There are 100 pole pairs around the circular disk on which the decomposer is arranged is, then each pole pair in space represents 360 ° (spatial angle) = 3.6 ° (space wind) (6) 100 pole pairs. Each pole pair represents 360 ° of the electrical phase shift when the sensor component runs over the drive element. So that requires If the pole pairs are present a hundredfold subdivision of the phase angle, namely 3.6 = 0.01 ° (rotation of the sensor component with respect to the phase component.

If the transmission ratio of the decomposer is given by G = zl, (7) where d0 is the angle of change of the probe in electrical degrees and i10 is equal to the change in the mechanical angle of the drive spindle, defined, the transformation ratio is equal to the number of pole pairs. Thus the angular translation of the decomposer is 100.

To record the direction of the shift in the output signal, becomes a two- or multi-phase detector system for the phase detectors 24, 36 and 44 applied. An example of such a phase detector circuit is shown in FIG which essentially contains two phase detector circuits, each of which is conventional May have construction and are connected so that they result in two output signals, which are 90 ° out of phase when the same input signals are applied will.

In the phase detector shown, the coils 60 have a center tap on, and a coil end 62 is connected to the center tap. The input signals, whose phase difference is to be measured are inductively connected to the corresponding Coils coupled, and the DC output voltages obtained in parallel with resistors 64 and 66 are proportional to the phase difference between the two input signals.

If the reference signal E sin wt with a signal E sin (wt + k #) des Decomposer is compared, then an output voltage Eans becomes equal to E sin k0 generated.

When the reference signal E sin wt is phase shifted by 90 ° and in introduced a second phase detector network and compared with the signal E sin (wt + k0) - results in Eout = E sin (k # + 90 °) = E cos k #.

The 90 ° phase shifting correction produces two signals E sin wt and E cos wt - formed from the reference carrier. E sin wt is with the message carrier E sin (wt + kO) in one phase detector and E cos wt with E sin (wt + k #) in one compared to another phase detector ~. Pie signals emitted by the detectors will be a cathode ray tube fed to the baffles, namely the one signal E sin kO the horizontal pair of plates, the other signal E cos kO the vertical Plate pair.

In this way, a beam position is achieved whose angular position is opposite to a Reference point is equal to kO.

Since 0 is continuously variable, k 0 is an analog quantity. The task of digitally processing this size is done by the digital device solved Suffice it to say that the in flight. 4 cathode ray tube shown allows the steel to be rotated in individual steps of 1/10 3600 per step, Da the beam rotates in individual stages, each stage is assigned an individual signal, which is saved for reading. The digital device can be any one be known system that works so that a change in the digital display Due to a change in the signal level of the static DC output signal from phase detector 26 takes place. Preferably for the digital device, however one in FIG. 4 is used, but if necessary, if necessary, may have other shapes. This analog-to-digital conversion is usually done by made a cathode ray tube or number tube, as it is known. the Cathode ray tube contains the usual components of an electron beam source including a heater 78, a cathode 80i of a grid 82, a high voltage electrode 84 and a focusing electrode 86, which by a suitable voltage source 88 is supplied.

The input signal is applied to the baffles 90 and 92 in such a way that that the electron beam scans a ten-part anode (94), of which in FIG. 4 only five anode segments are shown. Regarding the position of the beam spot There are three influencing fields on the tube anode, two of which namely the X and Y shift, the electron beam spot due to the 90 ° phase shifted Arrange input signals in a circle Immediately below these baffles are ten radially aligned deflection electrodes 96. Each of these deflection electrodes is connected to a corresponding anode segment 94. These have the property Send out secondary electrons due to the impact of the electron beam. The beam incident on an anode segment 94 causes the segment charge becomes positive because of the secondary emission. The loop to the corresponding deflection electrode 96 leads to the attraction of the beam, so that it is bent towards the deflection electrode will.

The beam then strikes the corresponding anode segment 94 to the point where the beam path is directly opposite the adjacent deflection electrode 96 moves. If the beam is moved from one anode segment to another, it takes place a retarding effect as the beam travels to one of the adjacent deflecting electrodes opposite point was turned. The delay effect is on the progress direction of the electron beam independently.

The counting tube acts as a directly coupled to the decomposer Amplifier and as such works in two directions. The maximum response speed of the individual tube is determined by the transit time of the electron beam and the RC time constant the anode is limited. for the correct phase relationship between the phase detectors to ensure the information-carrying signals supplied to the various counting tubes, are devices for introducing a fixed phase shift with respect to of the supplied signals to all digital digits, with the exception of the unimportant ones. If the numerical value in the counter tube in the second half of theirs Range is present, there will be a delaying phase shift that will increase in size is equal to half the required displacement for a single number (in the next higher digit), supplied to the information-carrying signal that is introduced into the paying agent of the next higher order. This prevents the counter tube of the next higher number position its display in front of the counter tube of the next lower digit changed from 9 to 0 or from 0 to 9.

A separate working resistance assigned to each of the anode segments 94 100 then emits a voltage when the electron beam hits this anode segment This gives an output signal that is in a digital or digital format. discontinuous form is present even when the input signal is continuous is. The output signal can be used to control conventional visual display circuits such as Display columns with neon tubes, an electric typewriter, a strip punch or line printers.

Examples of such acceptance circles are known.

The digital device thus results in a number of individual displays, which corresponds to the basis of the counting system used. Since usually a number system is used with the base 10, it is convenient to design the digital device so that that one out of ten individual displays for the 360 "of mechanical rotation of the movable Element in the decomposer 20 existing output signal is formed.

Since the dismantling type according to Fig. 2 360 "phase shift in the output signal delivers when the sensor component is mechanically only one hundredth of a revolution is rotated with respect to the drive component, each pole pair generates an identical one Phase information. To the need for a storage or integration device to avoid, which shows the total number of pole pairs passed through, can be a second drive and sensor element are connected to the same dismantling shaft, in order to provide such a coarse output signal, as is known per se. So can a drive and sensing device similar to the application with 100 pole pair units find how it is in connection with F i g. 2 is described. This similar pole pair set however contains either 99 or 101 pole pairs in the circuit.

In accordance with equation (7) given above, this is mechanical transmission ratio of this section of the disassembler is either 99 or 101, depending on the number of pole pairs used. By comparing the phase angle of a pole pair set with the phase angle of the other, as shown in FIG. 5 explained a rough indication is obtained as follows: The output signal from the oscillator 120 is fed to the input winding of section 1 of decomposer 122. That The output signal of section 1 is then also used to drive section 2 of the Decomposer 122 applied. The second section of the decomposer acts on that of the first Section, resulting in an output signal of the form sin (wt + O (n1-n (8) results.

A digital step or digit that represents the mechanical distance of the movable element pro- is proportional and therefore the most important level represents a multi-digit number can be obtained by a circuit at which is n1 = n2 + 1.

This is achieved in that, for. B. 100 pole pairs on the section 1 and 99 pole pairs are available on section 2. Since in this case the section 2 has one pole pair less than section 1 and there the same with the output signal fed by section 1, the hundred cyclic phase revolutions per revolution of the input shaft, subtracts the section 2 for each individual revolution of the Input shaft all values except for a single rotation of the input shaft. Therefore, the signal emitted by section 2 amounts to E sin (wt + @) O). This signal is the phase detector 127 of the first digit together with the reference signal E sin wt supplied from the oscillator 120. That from phase detector 127 Delivered output signal is fed to a digital device 128 and corresponds a 360 ° phase shift for every single revolution of the input shaft.

The output signal E sin wt +0 from section 2 of the decomposer becomes also fed to harmonic amplifier 129, where it is multiplied by ten and an output signal E sin 10 (where +0) results.

The reference carrier E sin wt of the oscillator 120 becomes the harmonic Amplifier 130 supplied where it is multiplied by 9 and an output signal E sin 9 (wt) results. The output signal of the nine-way amplifier (harmonic amplifier 130) and the output signal of the ten-fold amplifier (harmonic amplifier 129) are combined in mixer 131. The output of mixer 131 can be expressed as E sin (wt +100). If this output signal is sin with the reference carrier E wt of the oscillator 120 is compared in the phase detector 132, that is from the detector output signal is the phase angle increased by a factor of 10. the The number of the hundreds is derived from the output signal E sin (wt + 1000) of the section 1 of the decomposer 122 by means of the in FIG. 1 described multipliers and phase detectors won. The number of digits can be expanded by many different arrangements be carried out, of which the F i g. Figure 5 shows a preferred embodiment.

In Fig. 6 is a differential splitter 150 similar to that in FIG. 5, which has two sections, one of which is an electromechanical Gear ratio of 99 and the other has a mechanical ratio of 100. The oscillator 152 near the center of the diagram generates a signal of constant frequency, its output through line 154 to power amplifier 156 and through the phase shifter 158 is fed to the amplifier 160. The signal output from amplifier 156 is fed to an inductor of section 1 in the differential decomposer, the one mechanical translation of 100, and the output of the amplifier 160, the is 90 "out of phase with amplifier 156, the other inductor fed in section 1. An increase or

Increase in the movement of the shaft of the differential decomposer generated on Output of section 1 in line 162 a signal of the same frequency, however with a phase shift that is 100 times the mechanical shift of the movable decomposing element is displaced. This signal is passed through the amplifier 164 amplified, in the limiter 166 limited and then by the Conductor 168 to power amplifier 170 and through phase shifter 172 to power amplifier 174 supplied. Note that the actual waveform is not necessarily needs to be a sine wave, but also in the form of a Taylor series expansion can be expressed. The terms sin and cos are used to define the phase position to identify the various signals and not to indicate the exact shape of the wave. The signals output by the power amplifiers 170 and 174 are added to the section 2 of the differential splitter 150 supplied, which has a mechanical translation of 99 has. Since the phase shifter 158 is 90 "phase lead and the phase shifter 172 90 "generated, the differential decomposer subtracts the phase lag of section 2 from that of section 1, whereby an output signal is formed, its electrical phase is equal to the mechanical angle of rotation of the movable element on the differential splitter 150 is. This simplifies the application Circuit and leads to a more stable operation than when using the in Fig. 5 can be achieved.

The signal on line 176 thus becomes a "coarse" indicator signal and is amplified by amplifier 178 and limiting amplifiers 180. An output of amplifier 180 is on line 182 with the polyphase detector sections 184 and 186 in conjunction. The phase detector section 184 receives a second input signal from the output of power amplifier 160 via conductor 188. The second The input signal to the phase detector section 186 is from the output of the power amplifier 156 taken over the ladder 190. This phase detector has the one shown in FIG. 3 and provides an input to counter tube 192 that is proportional the most important number in the multi-digit sequence is the mechanical one Represents the phase position of the movable element of the differential splitter 150. As in connection with the F i g. 1 and 2 discussed are those on the phase detectors 184 and 186 transmitted accurate waveforms not critical as the counter tube only an output signal is generated that is accurate with respect to the closest 36 ° or a Tenth of 360 "is.

A second output signal of the limiting amplifier 180 is fed via conductor 194 to amplifier 196 generating the 10th harmonic, the output of which is fed to mixer 198 as an input signal Das The second input signal comes from a 9th harmonic generating amplifier 200, the output signal via the conductor 202 as the second input signal to the Mixer 198 is supplied. The output of mixer 198 is then used as Input signal fed to phase detectors 204 and 206, with the other input signal for each phase detector from power amplifiers 160 and 156 via the ladder 188 and 190 is obtained.

The mathematical analysis of phase expansion and digitizing the second most important digit in the coarse display, as related to the F i g. 5 shows the principles of phase expansion and processes the decadal display. The same considerations apply to those in Fig. 6 to the arrangement shown, however, the exact equations change due to the Circuits between the exit of section 1 of decomposer 150 and the entrance to the section 2 slightly.

The third most important digit of the multi-digit display becomes obtained that the output signal from section 1 of the differential decomposer 150, which passed through amplifiers 164 and 166 directly as input to the phase detector sections 240 and 242 is entered. The other is supplied to each phase detector section The input signal is the same as that applied to all phase detectors and how it is provided by power amplifiers 160 and 156.

The fourth most important digit of the numeric display is from conductor 243 which receives the signal of the third most important digit from the limiting amplifier 166 transmits, which is increased tenfold in frequency in harmonic amplifier 244 and then fed to the input of mixer 245. The other input signal for mixer 248, the 9th harmonic of the reference signal is that from the amplifier 204 comes in, which makes the output of the mixer a thousand times its phase the mechanical angle change shifts. This signal is sent to the phase detectors 247 and 246 given and supplies the fourth most important in the number display device 248 Pay digit.

The same output signal from the i45 mixer is applied to the harmonic Amplifier 250 transmit which generates a 10th harmonic which is fed to mixer 252 is fed. The second input to mixer 252 is from the harmonic Amplifier 200, and the phase of the output of mixer 252 is ten thousand times has been postponed.

This signal is applied to phase detectors 254 and 256, which then result in the fifth most important digit of the multi-digit number display.

A system that operates reliably has been described above and that divides the 360 "of a revolution into 100,000 parts. Experiments were carried out manufactured that perform 200,000 counts for one revolution.

Claims (4)

Claims 1. Radio location receiver for measuring a relative position of objects for which the measured variable is in the form of the mechanical position of a resolver is present and by measuring the electrical phase difference between that of the resolver supplied comparison oscillation and the oscillation emitted by it determined and in which the vibrations are frequency-multiplied to increase the measurement accuracy and the phase difference is converted into electrical digital values and converted into Is displayed in the form of numbers, characterized in that to carry out a multi-digit numbers moderate display of the phase difference for each digit special number display channels are provided in which for the first digit Subordinate digits each indicate the hteßvibration from the previous channel multiplied by n and mixed with the (ni1) -fold comparison oscillation, where n is the base of the number system used j and then with the comparison vibration in itself known phase meter for displaying the be supplied to the respective number digit. 2. Radio location receiver according to claim 1, characterized in that that the resolver has a large number of pole pairs for dividing the phase shift the comparison oscillation has from 0 to 360 "and that against the comparison oscillation phase-shifted oscillation - if necessary to an amplifier - emits. 3. radio location receiver according to claim2, characterized in that the resolver has a pole pair that can be swiveled from 0 to 360 "by means of rotating devices has, around which along the circumference of a circle the plurality of pole mate is arranged, which emit the phase-shifted oscillation. 4. radio location receiver according to claim 3, characterized in that that the output signal emitted by the pivotable pole pair as an input signal is fed to the pole pairs arranged around the pivotable pole pair. Documents considered: German Patent No. 661 924; U.S. Patent No. 2,947,985; Electronic Engineering, 1959, January, p. 13 to 15; Proceedings of the IEE, 1952, December, part IV, pp. 318-325.