Method for transmission of data

Abstract

The invention relates to a method for transmitting data in a system comprising a reader that creates an interrogation field which contains at least two transponders that, after a start signal has been given in the interrogation field, transmit through load modulation of the interrogation field a uniquely assigned bit sequence back to the reader. For fast and reliable identification of all transponders in the interrogation field, precisely one time slot for time modulation is provided for each possible significance of each bit position of the bit sequence to be transmitted. The transponders cease transmitting their bit sequence when they detect loading modulation in a time slot in which they themselves have not actively modulated the interrogation field by loading. After complete transmission of the uniquely assigned bit sequence of a transponder, this transponder is deactivated and the procedure is repeated with the other transponders in the interrogation field by again sending the start signal. The procedure is repeated until no further loading modulation takes place in all time slots of the first bit position. The particular distinguishing feature of the method is that for N transponders only N+1 interrogation cycles are needed to identify all transponders and that the entire value set available for the bit sequence can be allocated as identifier. Even transponders that come into the interrogation field after data transmission has begun are identified.

Dependencies are inferred from the claim text.