Method for transmitting data

• US 20050180380A1
• Filed: 01/15/2003
• Published: 08/18/2005
• Est. Priority Date: 02/01/2002
• Status: Abandoned Application

• Current Assignee: Atmel Corporation (Microchip Technology Incorporated)
• Original Assignee: Atmel Corporation (Microchip Technology Incorporated)
• Inventors: Friedrich, Ulrich
• Application Number:
  US10/503,256
• Publication Number:
  US 20050180380A1
• Time in Patent Office: Days
• US Class Current: 370/349
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: H04L 25/4902 Pulse width modulation; Pulse position modulation

Abstract

In known methods for the transmission of data the effective data transmission rate is reduced through errors in the data transmission, because the entire data word must respectively be transmitted again in the event of errors. With the new method, an error correction during the transmission of the data word is made possible through the change of the modulation state at pre-defined time points. Thereby the effective data transmission rate is increased.

Claims

1. Method for the transmission of data between a base station (BS) and a transponder (TR) by means of an electromagnetic wave, in which information packets (IP) are modulated onto the electromagnetic wave, which information packets comprise a header section (KO) with a data symbol and a data section (DA) with a data word, whereby the data symbol comprises plural logic values, and the data of the data section (DA) are encoded as a bit sequence of the data word by means of the logic values and are transmitted in reference intervals (Tx, Ty) generated by successive clock pulses, characterized in that

for the differentiation of the logic values of the data symbol, in the header section (KO), a time point (Z1-Z5) derived from the time duration of the reference interval (Tx, Ty) is allocated to each logic value, and

at least one bit is transmitted within the reference interval (Tx, Ty), and

the modulation of the electromagnetic wave is changed at the time point (Z1-Z5) allocated to the logic value of the bit.

2. Method according to claim 1, characterized in that two bits are transmitted within the reference interval (Tx, Ty), and the modulation is changed at the time point allocated to the logic value of the first bit, and insofar as the second bit comprises a different logic value, the modulation is changed at the half time duration of the reference interval (Ty).

3. Method according to claim 1, characterized in that the modulation of the electromagnetic wave begins with a prescribed modulation state in the transmission of the first bit of the data word.

4. Method according to claim 1, characterized in that the magnitude of the reference interval is determined from the magnitude of the time interval of two successive synchronization signals.

5. Method according to claim 1, characterized in that, in the transponder (TR), the time points transferred from the base station (BS) in the header section (KO) of an information packet (IP), for the decoding of the data word, are stored in a volatile memory.

6. Method according to claim 1, characterized in that, in the transponder (TR), for the decoding of the data word, a value of a charge state of a capacitor is allocated to the time point (Z1-Z5) transferred from the base station.

7. Method according to claim 1, characterized in that the length of the reference interval (Tx, Ty) is changed for the adjusted setting of the spacing distances of the sidebands relative to the middle frequency of the modulated electromagnetic wave.