TH21135A - The process for reading data stored in a transponder using a transceiver. - Google Patents

Abstract

The described process is for reading data stored in a transponder using a transponder-transmitter mechanism. To read data from a transponder operating in full duplex, which encodes the data in different ways, the transponder converts the incoming data into a digital format. It determines the encoding type, and depending on the encoding type, a digital evaluation circuit performs various functions to evaluate the data.

Claims (13)

1. The process for reading data stored in a transponder involves a transponder that converts the data received from the full-duplex transponder into a digital format. The transponder then performs Fourier analysis on at least some of the data using a digital evaluation circuit. This process is unique in that when reading data from different types of full-duplex transponders using different encoding types in the Fourier spectrum, the frequency component characteristics of each encoding type are determined. Thus, the encoding type is detected, and the digital evaluation circuit generates different processing functions depending on the detected encoding type. 2. In accordance with claim 1, the carrier frequency is filtered out of the data transferred by a full-duplex transponder before the data is translated into digital form. 3. A process consistent with either claim 1 or 2 herein, using the Manchester Encoding model which utilizes data amplitude as a characteristic of the encoding to evaluate the digitized data - will filter this data using a digital bandpass filter, the transmission range of which should ideally be in the range of 1-2 kHz - will search for the starting Manchester Encoding code in order to read the logical value of specific data bits. 4. A process that complies with either claim 1 or 2, by encoding the logical representation of 0 at frequency one, by which the amplitude is switched between the two values, and by encoding the logical representation of 1 at frequency two, by which the amplitude is switched between the two values, in order to evaluate the digitally converted data - this data is filtered by a digital band-pass filter, the transmission range of which includes both frequencies - Fourier analysis of this data with the width of the data bits is performed for the detection of the beginning of the data bits and for the reading of the data bits. 5. A process consistent with one or more claims herein shall, by means of Manschelter coding using a frequency which alternates the amplitude of the data between two values as a characteristic of the code in order to evaluate the digitized data - this data shall be filtered by a digital band-pass filter in which the transmission range shall include both frequencies - Fourier analysis shall be performed on the entire data to determine the correction factor - Fourier analysis shall be performed on the data with half the width of the data bits only for the detection of the beginning of the data bits and for reading only the data bits. 6. A process consistent with either claim 1 or 2 herein shall be performed by phase encoding the data. Thus, the amplitude level of the data is alternated between two values at a specific frequency, and between the logical value 0 and the logical value 1, a phase shift of half a time constant of the switching period is made. In order to evaluate the digitized data, this data is filtered by a digital band-pass filter whose range includes the switching frequency. Subsequently, each time constant of the switching period forms a difference between two amplitude values that are half a time constant apart, and these differences are added together to form a sum. To determine the start of the data bits, the last value of such a sum is detected, and to read the logical value of the data bits, a digital sign of such a sum is assigned to each data bit. 7. The process consistent with claim 1 herein for reading data from a transponder involves the transponder transmitting different carrier frequencies in a specific temporal sequence. 8. A process consistent with any of claims 1 through 7 herein, during a momentary pause in frequency transmission, the carrier checks whether a field returned from a transponder operating in half-duplex is being received. 9. A process consistent with claim 9 herein, if it is established that a field is being received by a half-duplex transponder, would cause such a pause to be extended until all data transmitted by the half-duplex transponder has been received, whereas otherwise transmission at the carrier frequency would continue after a correspondingly shorter pause. 10. A process consistent with either claim 8 or 9 herein, for the reception of a half-duplex transponder field, will reduce the transmit/receive resonance circuit queue factor. 11. A process that complies with either claim 8 or 9 herein reads data from a half-duplex transponder which sends a field at one frequency to transmit a logical value 0 and a field at a second frequency to transmit a logical value 1 - filters the received signal by a band-pass filter, which improves the transmission range to include both frequencies - transforms the signal by a comparator into a rectangular signal, and - counts the zeros of the rectangular signal by a digital evaluation circuit to determine the signal frequency. 12. A process that complies with any of claims 8 through 10 herein for reading data from a half-duplex transponder which sends a field at frequency one to transmit a logical value 0 and a field at frequency two to transmit a logical value 1 - will convert the data received by the transponder by an analog-to-digital converter circuit to determine the signal frequency - will perform Fourier analysis of each data bit for reading the converted format. 13. A process consistent with claim 12 herein shall be performed where the sample washing frequency of the analog-to-digital converter is lower than the frequency of the two signals and for the readout shall determine and evaluate the Fourier component of the data at the two shadow frequencies resulting from the combination of the signal frequency and the sample washing frequency.