# US 2013/0154688 A1 · Method for Detecting a Working Area and Device Therefor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0154688 A1 - Document ID: US20130154688A1 - Status: Published application - Kind: A1 - Application number: 13/643,942 - Filed: 2011-02-28 - Published: 2013-06-20 - Earliest claimed: 2010-04-27 - Assignees: Robert Bosch GmbH - Inventors: Steffen Petereit; Amos Albert - Web page: https://patentgrep.com/patent/US20130154688A1 ## CPC - H03K 5/22: Circuits having more than one input and one output for comparing pulses or pulse trains with each other according to input signal characteristics, e.g. slope, integral (indicating phase difference of two cyclic pulse trains G01R25/00) - A01K 15/023: {Anti-evasion devices} - G05D 1/0265: {using buried wires} - H03K: PULSE TECHNIQUE (measuring pulse characteristics G01R; modulating sinusoidal oscillations with pulses H03C; transmission of digital information H04L; discriminator circuits detecting phase difference between two signals by counting or integrating cycles of oscillation H03D3/04; automatic control, starting, synchronisation or stabilisation of generators of electronic oscillations or pulses where the type of generator is irrelevant or unspecified H03L; coding, decoding or code conversion, in general H03M) - A01K: ANIMAL HUSBANDRY; AVICULTURE; APICULTURE; PISCICULTURE; FISHING; REARING OR BREEDING ANIMALS, NOT OTHERWISE PROVIDED FOR; NEW BREEDS OF ANIMALS - G05D: SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES ## Abstract A method for detecting a position with respect to a mobile working machine includes providing a current signal in a boundary conductor, which surrounds the defined area, in accordance with a boundary signal that is provided, the boundary signal corresponding to a pseudo-accident signal; and receiving a detection signal of a magnetic field. The method further includes generating a reconstructed boundary signal from the detection signal; providing a reference signal which has a bit pattern corresponding to the boundary signal provided; carrying out a correlation method in order to determine a time-based correlation offset between the reference signal and the reconstructed boundary signal and a correlation value between the reference signal and the reconstructed boundary signal, which are displaced in relation to each other by the correlation offset determined; and determining a position inside or outside the defined area as a function of the correlation value determined. ## Claims ### Claim 1 A method for detecting a position with respect to a defined area comprising: providing a current signal in a boundary conductor, which surrounds the defined area, according to a boundary signal which has been provided, the boundary signal corresponding to a pseudo-random signal; receiving a detection signal from a magnetic field generated by the current signal in the boundary conductor; generating a reconstructed boundary signal from the detection signal; providing a reference signal having a bit pattern corresponding to the boundary signal which has been provided; carrying out a correlation method in order to determine a temporal correlation offset between the reference signal and the reconstructed boundary signal and in order to determine a correlation value between the reference signal and the reconstructed boundary signal which have been shifted with respect to one another by the correlation offset which has been determined; and determining a position inside or outside the defined area on the basis of the correlation value which has been determined. ### Claim 2 A method for detecting a position with respect to an area defined by an alternating magnetic field, comprising: receiving a detection signal which corresponds to a voltage induced by the alternating magnetic field; generating a reconstructed boundary signal from the detection signal; providing a reference signal, the reconstructed boundary signal and the reference signal corresponding to a pseudo-random signal; carrying out a correlation method in order to determine a temporal correlation offset between the reference signal and the reconstructed boundary signal and in order to determine a correlation value between the reference signal and the reconstructed boundary signal which have been shifted with respect to one another by the offset which has been determined; and determining a position inside or outside the area on the basis of the correlation value which has been determined. ### Claim 3 (depends on 2) The method as claimed in claim 2, wherein the pseudo-random signal is a binary signal with a quasi-random sequence of levels and corresponds to a periodic bit pattern which is selected in such a manner that a length of a section of the periodic bit pattern, which is identical to a section of the inverted bit pattern of the same length, undershoots a predefined part of the total length of the bit pattern. ### Claim 4 (depends on 2) The method as claimed in claim 2, wherein the boundary signal corresponds to a gold code. ### Claim 5 (depends on 2) The method as claimed in claim 2, wherein the temporal correlation offset between the reference signal and the reconstructed boundary signal is determined by determining a plurality of correlation values for different temporal offsets and by determining the temporal correlation offset as the temporal offset for the correlation value of the largest magnitude. ### Claim 6 (depends on 2) The method as claimed in claim 2, wherein the correlation value is determined with the aid of a cross-correlation function by adding or multiplying samples of the reconstructed boundary signal and time values of the reference signal. ### Claim 7 A device, comprising: a detector unit configured to receive a detection signal from a magnetic field generated by the current signal in a boundary conductor; a reference signal generator configured to provide a reference signal which has a bit pattern corresponding to the boundary signal which has been provided; and an evaluation unit which is designed configured (i) to generate a reconstructed boundary signal from the detection signal, to carry out a correlation method in order to determine a temporal correlation offset between the reference signal and the reconstructed boundary signal and in order to determine a correlation value between the reference signal and the reconstructed boundary signal which have been shifted with respect to one another by the offset which has been determined, and to determine a position inside or outside the area on the basis of the correlation value which has been determined. ### Claim 8 (depends on 7) The device of claim 7, further comprising: a boundary signal generator configured to provide a current signal in a boundary conductor, which surrounds a defined area, according to a boundary signal which has been provided, the boundary signal corresponding to a pseudo-random signal. ### Claim 9 (depends on 8) The device of claim 8 wherein: the device is part of a system for detecting a position with respect to an area, and the system includes (i) the boundary conductor which surrounds the area, (ii) the device, and (iii) the boundary signal generator, which injects a current signal into the boundary conductor. ### Claim 10 (depends on 2) The method as claimed in claim 2, wherein a computer program product contains a program code which carries out the method when executed on a data processing unit. ### Claim 11 (depends on 9) The device as claimed in claim 9, wherein: the device is used in a mobile working device, and a movement of the mobile working device is allowed only inside the area and in which the direction of the mobile working device is changed upon reaching the boundary conductor. ### Claim 12 (depends on 9) The device as claimed in claim 9, wherein: the device is used in a monitoring device, and a function of the monitoring device is triggered upon leaving the area. ### Claim 13 (depends on 9) The device as claimed in claim 9, wherein: the device is used in a tracking device, and the tracking device changes direction in the direction of the boundary conductor if the position of the tracking device is detected as being inside or outside the area.