DE102013226986A1 - Bearing system and bearing method with compensation of environmental influences - Google Patents

Abstract

A bearing system (1) is used to find a bearing signal. It includes a direction finding antenna device (11) for receiving the direction finding signal and a processing device (10) for determining the bearing position based on the received direction signal. The processing device (10) further includes an antenna reference database (16) in which first antenna reference data is held. The processing device (10) further includes a calibration device (15). The latter receives antenna calibration data by means of the direction finding antenna device (11) and determines second antenna reference data based on the received antenna calibration data and the first antenna reference data read from the database (16). Furthermore, the processing device (10) includes a direction finder (14), which performs the bearing based on the second antenna reference data and based on the received bearing signal.

Description

The invention relates to a direction finding system and a direction finding method, which influences the environment, e.g. Aging effects or influences of the surrounding geometry, compensate.

Conventionally, in the manufacture of a bearing system, antenna reference data is measured as a reference antenna voltage in response to a receiving antenna element, an azimuth, an elevation, a frequency, and a polarization having a plurality of nodes. Based on these antenna reference data, signals of the bearing system obtained in the course of a bearing measurement are calculated in order to be able to carry out the most accurate bearing possible. However, due to mechanical stresses during transportation, aging phenomena, scattering, diffraction and reflection in the target environment, and tolerances of the antenna orientation in all three dimensions, new conditions arise in the target environment of the bearing system, which are different from the antenna reference data determined during manufacture differ. However, a renewed complete measurement of the bearing system in the target environment is not possible due to the very numerous necessary support points.

Exemplary shows the German patent application DE 10 2004 020 276 A1 a corresponding bearing system. Even with this bearing system accurate DF results can be achieved only after a complex calibration described above.

The invention has for its object to provide a bearing system and a method for bearing, which allow a highly accurate bearing with low calibration effort.

The object is achieved for the direction finding system by the features of independent claim 1 and for the method by the features of independent claim 11. Advantageous developments are the subject of the dependent claims.

A direction finding system according to the invention serves to find a bearing signal. This includes a DF antenna device for receiving the DF signal and a processing device for determining the bearing based on the received DF signal. The processing device further includes an antenna reference database in which first antenna reference data are held. The processing device further includes a calibration device. The latter receives antenna calibration data by means of the direction finding antenna device and determines second antenna reference data based on the received antenna calibration data and the first antenna reference data read from the database. It is not necessary to perform a variety of calibration measurements. Only a manageable number of antenna calibration data must be received in order to determine the second antenna reference data and thus be able to perform a highly accurate bearing.

Furthermore, the processing device preferably includes a direction finding device, which performs the bearing based on the second antenna reference data and based on the received bearing signal.

Preferably, the calibration device is designed to determine the second antenna reference data by interpolation and / or regression of the antenna calibration data. In this way, support points of the antenna calibration data that are far from each other can be used to determine the second antenna reference data and thus enable a highly accurate bearing.

Preferably, the first antenna reference data and the second antenna reference data and the antenna calibration data are antenna levels, in particular antenna voltages, which are in each case dependent on an antenna element, an azimuth, an elevation, a frequency and a polarization. This allows highly accurate DF results to be achieved without the need for any additional processing steps.

The first reference antenna voltages or levels and the second reference antenna voltages or levels respectively have L supporting points. The calibration antenna voltages or levels then have M reference points. L is larger, preferably at least 50 times larger, more preferably at least 1000 times larger than M. So can be carried out with a very small number of nodes of the calibration antenna voltages or level a highly accurate bearing.

Preferably, the calibration device is designed to determine the calibration quotient of the first reference antenna voltages or levels and the calibration antenna voltages or levels at the M nodes of the calibration antenna voltages or levels. Furthermore, it is designed to perform an interpolation and / or regression of the calibration quotients resulting in reference quotients for all L support points and the second reference antenna voltages or levels by multiplying the reference quotients with the first reference antenna voltages or levels determine.

Alternatively, the calibration device is designed to determine calibration differences of the first reference antenna voltages or levels and the calibration antenna voltages or levels at the M nodes of the calibration antenna voltages or levels, and an interpolation and / or regression of the calibration differences as a result of reference differences for all L reference points. Furthermore, it is designed to determine the second reference antenna voltages or levels by adding the reference differences to the first reference antenna voltages or levels. By the two methods described above, the second reference antenna voltages or levels can be determined with little computational effort.

Preferably, the interpolation is a trilinear interpolation and / or a tricubic interpolation and / or a spline interpolation. Alternatively or additionally, a regression function on which the regression is based is a polynomial of the nth degree or a spherical surface function. Alternatively or additionally, at least one of the variables, antenna element, azimuth, elevation, frequency and / or polarization enters logarithmically during the interpolation and / or regression. Thus, a very accurate approximation of a curve of reference antenna voltages or levels obtainable by a multiplicity of support points can be achieved. At the same time only a small amount of computing power is needed.

Preferably, the direction finding system further comprises a calibration transmitting device for transmitting calibration signals, which are received by the calibration device by means of the direction finding antenna device as antenna calibration data. So no external components are necessary. The whole bearing can be done with the direction finding system.

Preferably, the calibration device is designed to additionally use in the determination of the second antenna reference data aging information and / or information with respect to a geometry of a location of the bearing system. Thus, any additional information that is available anyway can be used to further increase the accuracy of the calibration.

A method according to the invention serves to find a bearing signal. The bearing signal is received and determines the bearing based on it. First antenna reference data are kept available. Antenna calibration data is received. Based on the reserved first antenna reference data and the received antenna calibration data, second antenna reference data are determined.

Preferably, the bearing is determined on this and the received bearing signal. Thus, a highly accurate bearing can be achieved with little computational effort.

The invention will be described by way of example with reference to the drawing, in which an advantageous embodiment of the invention is shown. In the drawing show:

1 an embodiment of the invention Beilsystems as a block diagram;

2 a diagram with antenna reference data;

3 a detailed view of the embodiment of the invention Peilsystem as a block diagram, and

4 an embodiment of the method according to the invention in a flowchart.

First, based on the 1 the general structure and the general operation of an embodiment of the direction finding system according to the invention explained. Based on 2 is then dealt with the underlying problem and details of the function of the embodiment. Based on 3 Further details of the construction and the function of the embodiment of the direction finding system according to the invention are illustrated. Finally, based on 4 on the function of an embodiment of the method according to the invention. Identical elements were not shown and described in similar illustrations.

In 1 is a first embodiment of the direction finding system according to the invention 1 shown. The bearing system 1 includes a direction finding antenna device 11 , which with a processing device 10 connected is. The direction finding antenna device includes a plurality of antenna elements whose signals are received separately and further processed. In addition, the bearing system includes 1 a calibration transmitter 20 ,

The bearing antenna device 11 is designed to receive DF signals and to the processing device 10 forward. The processing device 10 receives the received bearing signals of the bearing antenna device and determines the bearing of the received bearing signal.

On the detailed function of the processing device 10 is determined by 3 discussed in more detail.

In the production of the bearing system 1 an initial calibration is performed. That is, first antenna reference data are determined at a plurality of nodes L. The first antenna reference data in the exemplary embodiment are first reference antenna voltages V _ref (k, α, ε, f, ρ). These first reference antenna voltages are dependent on the antenna element k, the azimuth α, the elevation ε, the frequency f and the polarization п. This first measurement takes place under optimum environmental conditions. Instead of voltages, other level quantities, such as currents or power, may also be used, which depend on the field strengths detected at the antennas.

In 2 are in a diagram first antenna reference data 30 shown. The plurality of nodes M of the first antenna reference data is by puncturing the characteristic 30 indicated. In 2 the antenna reference data are shown only as a two-dimensional size, in the example as voltage as a function of an azimuth. In fact, however, the antenna reference data and antenna calibration data are multi-dimensional variables rather than voltage versus antenna element, azimuth, elevation, frequency and polarization.

After the bearing system has been brought to its place of installation and mounted there, deviations from the initially determined first antenna reference data result from mechanical stress during transport, aging effects, scattering, diffraction and reflection in the target environment and tolerances of the antenna orientation in all three dimensions , In order to avoid a costly renewed complete calibration measurement on all L support points, only one measurement is made at M support points. M is smaller than L. Preferably, M is smaller by at least a factor of 50, more preferably by at least a factor of 1000.

The antenna calibration data 31 have a significantly greater distance from each other than the first antenna reference data 30 , The processing device 10 out 1 determines second antenna reference data from the received antenna calibration data 32 by performing an interpolation or regression of a quotient or difference of the first antenna reference data and the antenna calibration data. This will be explained in detail on the basis of 3 and 4 received.

In 3 is a detail view of the processing device 10 and the beacon antenna device 11 out 1 shown. The bearing antenna device 11 includes a plurality of antenna elements 12 , which with a receiving device 13 are connected. The antenna elements 12 receive the beacon signal and direct their respective received signals separately to the receiving device 13 Next, which performs a preprocessing of the signals. For example, preamplification, filtering and digitizing are performed. Resulting signals are sent to the processing device 10 forwarded.

The processing device 10 includes a direction finding device 14 , a calibration device 15 , an antenna reference database 16 and a display device 17 , The direction finder 14 and the calibration device 15 are doing with the Peil antenna device 11 , in particular with the receiving device 13 , connected. Furthermore, the direction finder 14 and the calibration device 15 each with the antenna reference database 16 and the display device 17 connected.

The from the receiving device 13 preprocessed signals of the antenna elements 12 be the direction finder 14 and the calibration device 15 fed. In the antenna reference database 16 are first antenna reference data held, which were determined in a previously described initial calibration measurement in the preparation of the bearing system and stored there. Alternatively, the direction finding system determines 1 even the first antenna reference data based on a first calibration measurement, in which a plurality of measurement points is sampled.

After the direction finding system 1 was mounted at its place of use, a new calibration measurement is performed. It will be from the Peil antenna device 11 Antenna calibration data received. These become the calibration device 15 fed. The calibration device 15 determined from the antenna calibration data and the first antenna reference data from the antenna reference database 16 reads out, second antenna reference data. These are optionally stored again in the antenna reference database.

In determining the second antenna reference data, the calibration device determines 15 Quotients between the antenna calibration data Kal and the first antenna reference data ref. 1 according to the following equation:

The quotient Q _kal (k, α, ε, f, ρ) is determined for the M interpolation points of the calibration antenna _voltages V _kal (k, α, ε, f, ρ). This depends on the number index k of the antenna element, the azimuth α, the elevation ε, the frequency f and the polarization п. Subsequently, an interpolation and / or regression of the calibration quotients Q _kal (k, α, ε, f, ρ) results in reference quotients Q _ref (k, α, ε, f, ρ) for all L sample points of the first antenna reference Data V _{ref, 1} (k, α, ε, f, ρ). The second reference antenna voltages V _{ref, 2} (k, α, ε, f, ρ) are obtained by multiplying the reference quotients Q _ref (k, α, ε, f, ρ) by the first reference antenna voltages V _{ref, 1} (k, α, ε, f, ρ) determined according to the following equation: V _{ref, 2} (k, α, ε, f, ρ) = Q _ref (k, α, ε, f, ρ) · V _{ref, 1} (k, α, ε, f, ρ)

Instead of a quotient, a difference can alternatively be used. In this case, calibration differences D _kal (k, α, ε, f, ρ) of the first reference antenna voltages V _{ref, 1} (k, α, ε, f, ρ) and the calibration antenna _voltages V _kal (k, α, ε, f, п) are determined at the M interpolation points of the calibration antenna _voltages V _kal (k, α, ε, f, ρ). Subsequently, an interpolation or regression of the calibration differences D _kal results as a result of reference differences D _ref (k, α, ε, f, ρ) for all L interpolation points. The second reference antenna voltages V _{ref, 2} (k, α, ε, f, ρ) are then multiplied by adding the reference differences D _ref (k, α, ε, f, ρ) to the first reference antenna voltage V _ref ( _FIG. k, α, ε, f, ρ).

For the interpolation or regression of the calibration quotients Q _kal (k, α, ε, f, ρ) or the calibration differences D _kal (k, α, ε, f, ρ), a trilinear interpolation and / or a tricubic interpolation and / or a spline interpolation with a spline n-th

Grades and / or used as a regression function polynomial n-th degree or spherical surface function. One or several variables can logarithmically be included in the interpolation or regression.

In this case, preference is given to choosing an interpolation if the relative statistical and systematic measurement uncertainty of each individual one of the measured values Q _kal (k, α, ε, f, ρ) or D _kal (k, α, ε, f, ρ) is smaller or is equal to the measurement uncertainty of the original calibration measurement during manufacture. Otherwise, a regression function is preferable.

In addition to pure interpolation or regression, pre-information that is already known can be used. Thus, information regarding a typical aging history or information regarding a typical environmental geometry can be used to determine the second antenna reference data.

In 4 an embodiment of the method according to the invention is shown in a flow chart. In a first step 100 a first number L of first measuring points is determined during an initial reference measurement. In a second step 101 first antenna reference data is determined based on the first initial reference measurement. The steps 100 and 101 are carried out only in the production of the DF system. In a third step 102 a second number M of second measuring points is determined during a calibration measurement. The second number M of measuring points is significantly smaller than the first number L of measuring points. With regard to the number of measuring points, reference is made to the comments on the exemplary embodiment of the bearing system. In a fourth step 103 Second antenna reference data are determined based on the first antenna reference data and the second measurement points. Also with regard to this step, reference is made to the comments on the bearing system. The steps 102 and 103 be carried out after installation of the bearing system at its place of use. In addition, these steps can be repeated again if changes in the bearing system have resulted from signs of aging or changes to the surrounding geometry. In a fifth step 104 a bearing measurement is performed based on the second antenna reference data.

The invention is not limited to the illustrated embodiment. In particular, bearing systems can be used with any number of antenna elements. Also, the invention is not limited to a particular DF method. All direction finding techniques using antenna reference data for bearing detection or correction are covered by the present invention. All features described above or features shown in the figures can be combined with each other in any advantageous manner within the scope of the invention.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102004020276 A1 [0003]

Claims (19)

Bearing system for bearing a bearing signal with a direction finding antenna device ( 11 ) for receiving the direction-finding signal and a processing device ( 10 ) for determining the bearing based on the received bearing signal, characterized in that the processing device ( 10 ) an antenna reference database ( 16 ), which is designed to provide first antenna reference data, that the processing device (15) 10 ) a calibration device ( 15 ), which is designed to - by means of the direction finding antenna device ( 11 ) Receive antenna calibration data, and - determine second antenna reference data based on the received antenna calibration data and the first antenna reference data. Bearing system according to claim 1, characterized in that the processing device ( 10 ) a direction finding device ( 14 ), which is designed to determine the bearing on the basis of the received bearing signal and the second antenna reference data. Bearing system according to claim 1 or 2, characterized in that the calibration device ( 15 ) is adapted to determine the second antenna reference data by interpolation or regression of the antenna calibration data. Bearing system according to one of claims 1 to 3, characterized in that the first antenna reference data first reference antenna level V _{ref, 1} (k, α, ε, f, π), the antenna calibration data calibration antenna level V _kal (k, α, ε, f, π) and the second antenna reference data second reference antenna level V _{ref, 2} (k, α, ε, f, π), each depending on an antenna element k, a Azimuth α, an elevation ε, a frequency f and / or a polarization π present. Bearing system according to claim 4, characterized in that the first reference antenna level V _{ref, 1} (k, α, ε, f, π) and the second reference antenna level V _{ref, 2} (k, α, ε, f, π) have L supporting points in each case that the calibration antenna _levels V _kal (k, α, ε, f, π) have M support points, and that L is larger, preferably at least 50 times larger, more preferably at least 1000 times larger than Damn. Bearing system according to claim 5, characterized in that the calibration device ( 15 ) is designed to - calibration quotient Q _kal (k, α, ε, f, π) of the first reference antenna level V _{ref, 1} (k, α, ε, f, π) and the calibration antenna level V _kal ( k, α, ε, f, π) at the M interpolation points of the calibration antenna level V _kal (k, α, ε, f, π), - an interpolation and / or regression of the calibration quotients Q _kal (k, α, ε, f, π) resulting in reference quotients Q _ref (k, α, ε, f, π) for all L nodes, and - the second reference antenna levels V _{ref, 2} (k, α, ε, f, π) by multiplying the reference quotients Q _ref (k, α, ε, f, π) by the first reference antenna levels V _{ref, 1} (k, α, ε, f, π). Bearing system according to claim 5, characterized in that the calibration device ( 15 ) is _configured to - calibration differences D _kal (k, α, ε, f, π) of the first reference antenna level V _{ref, 1} (k, α, ε, f, π) and the calibration antenna level V _kal ( k, α, ε, f, π) at the M interpolation points of the calibration antenna _levels V _kal (k, α, ε, f, π), - an interpolation and / or regression of the calibration differences D _kal (k, α, ε, f, π) resulting in reference differences D _ref (k, α, ε, f, π) for all L nodes, and - the second reference antenna voltages V _{ref, 2} (k, α, ε, f, π) by adding the reference differences D _ref (k, α, ε, f, π) to the first reference antenna voltages V _{ref, 1} (k, α, ε, f, π). Bearing system according to Claim 6 or 7, characterized in that the interpolation is a trilinear interpolation or a tricubic interpolation or a spline interpolation, and / or that a regression function on which the regression is based is an n-th degree polynomial or spherical surface function, and / or that at least one of the variables antenna element k, azimuth α, elevation ε, frequency f and / or polarization π is used logarithmically in the interpolation and / or regression. Bearing system according to one of claims 1 to 8, characterized in that the direction finding system ( 1 ), a calibration transmitter ( 20 ) which is designed to emit calibration signals which are output by the calibration device ( 15 ) by means of the direction finding antenna device ( 11 ) are received as antenna calibration data. Bearing system according to one of claims 1 to 9, characterized in that the calibration device ( 15 ) is designed to additionally use in the determination of the second antenna reference data aging information and / or information with respect to a geometry of a location of the bearing system. Method for finding a bearing signal, whereby a direction signal is received, wherein the bearing is determined based on the received beacon signal, characterized in that first antenna reference data is retained, that antenna calibration data is received, and that based on the received antenna calibration data and the first antenna reference data , second antenna reference data are determined. A method according to claim 11, characterized in that the bearing is determined on the basis of the received bearing signal and the second antenna reference data. A method according to claim 12, characterized in that the second antenna reference data are determined by interpolation and / or regression of the antenna calibration data. Method according to one of Claims 11 to 13, characterized in that the first antenna reference data are first reference antenna levels V _{ref, 1} (k, α, ε, f, π), the antenna calibration data are calibration antenna levels V _kal (k, α, ε, f, π) and the second antenna reference data are second reference antenna levels V _{ref, 2} (k, α, ε, f, π), each depending on an antenna element k, a Azimuth α, an elevation ε, a frequency f and / or a polarization π present. Method according to Claim 14, characterized in that the first reference antenna levels V _{ref, 1} (k, α, ε, f, π) and the second reference antenna levels V _{ref, 2} (k, α, ε, f, π) have L supporting points in each case that the calibration antenna _levels V _kal (k, α, ε, f, π) have M support points, and that L is larger, preferably at least 50 times larger, more preferably at least 1000 times larger than M. is. A method according to claim 15, characterized in that calibration quotients Q _kal (k, α, ε, f, π) of the first reference antenna level V _{ref, 1} (k, α, ε, f, π) and the calibration antenna level V _kal (k, α, ε, f, π) at the M nodes of the calibration antenna level V _kal (k, α, ε, f, π) are determined that an interpolation and / or regression of the calibration quotient Q _kal (k, α, ε, f, π) resulting in reference quotients Q _ref (k, α, ε, f, π) is performed for all L nodes, and that the second reference antenna levels V _{ref, 2} (k, α, ε, f, π) by multiplying the reference quotients Q _ref (k, α, ε, f, π) with the first reference antenna levels V _{ref, 1} (k, α, ε, f, π) are determined , A method according to claim 15, characterized in that calibration differences D _kal (k, α, ε, f, π) of the first reference antenna level V _{ref, 1} (k, α, ε, f, π) and the calibration antenna level V _kal (k, α, ε, f, π) at the M nodes of the calibration antenna level V _kal (k, α, ε, f, π) are determined that an interpolation or regression of the calibration differences D _kal (k , α, ε, f, π) resulting in reference differences D _ref (k, α, ε, f, π) is performed for all L nodes, and that the second reference antenna levels V _{ref, 2} (k, α, ε, f, π) can be determined by adding the reference differences D _ref (k, α, ε, f, π) to the first reference antenna levels V _{ref, 1} (k, α, ε, f, π). Method according to claim 16 or 17, characterized in that the interpolation is a trilinear interpolation and / or a tricubic interpolation and / or a spline interpolation, and / or that a regression function on which the regression is based has an nth degree polynomial or a spherical surface function is, and / or that at least one of the variables antenna element k, azimuth α, elevation ε, frequency f or polarization π is used logarithmically in the interpolation and / or regression. Method according to one of claims 11 to 18, characterized in that additionally used in the determination of the second antenna reference data aging information and / or information with respect to a geometry of a location of the bearing system.

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