Patent ID: 11914095
Assignee: NOKTA MUHENDISLIK A.S.
Field: Measurement (Instruments)
Classification: CPC G  H | IPC G  H

Claim 0:
1. A method for obtaining information related to a target presence and/or a target kind for metal detectors, the method comprising:
sampling a signal by at least one Analog to Digital Converter (ADC) which is received through a receiver unit wherein said signal is generated as a result of a reaction of said target to a magnetic field transmitted by a transmitter unit;
by a controller, utilizing a Discreet Fourier Transform (DFT) based transformation technique consisting of summing of samples where each sample is multiplied by coefficients corresponding to a timing within a period in order to be expressed in terms of components of phase/magnitude or time constants for obtaining said information;
by said controller, providing the transmitter unit to transmit a reference signal where said reference signal is divided into time intervals where said time intervals are indexed by reference timing values;
by the controller, providing the receiver unit to receive and the ADC to sample said reference signal;
by the controller, detecting a phase shift for each sampling of the ADC according to a reference timing value;
by the controller, updating a table, the table defined for the timing intervals that are smaller than or equal to sampling intervals of the ADC and multiplying coefficients corresponding to a defined time with acquired samples,
by the controller, providing the transmitter unit to transmit a signal for detection,
by the controller, providing the receiver unit to receive and the ADC to sample said signal,
by the controller, defining nearest timing of each acquired sample from the table by using said table and determining corresponding coefficients for each sample; and
by the controller, obtaining phase/magnitude and/or time constant components of targets by using the sum of the asynchronously acquired samples, each multiplied by the corresponding coefficient.