Communication system and anti-collision method

1. A receiving method for contactless reception of identification from a data carrier through information units by a communication device, the method comprising:

receiving a received information unit, wherein said communication device uses said received information unit as a first information unit originating from a first data carrier;

waiting to deliver a first replacement information unit to at least the first data carrier and a second data carrier in a contactless manner until a collision is detected;

detecting said collision when said communication device receives at least two different information units with different values essentially simultaneously, wherein the first information unit originates from the first data carrier and a second information unit originates from the second data carrier;

using, as said first information unit originating from the first data carrier, a first replacement information unit established by the communication device instead of said received information unit only when the collision is detected; and

delivering said first replacement information unit to at least the first data carrier and the second data carrier in a contactless manner when the collision is detected, wherein said first replacement information unit halts only the second data carrier from continuing delivery of an information unit immediately following the previously delivered second information unit.

2. The receiving method of claim 1 , further comprising:

storing said received information unit as the second information unit originating from the second data carrier prior to said collision.

3. The receiving method of claim 2 , further comprising:

using a second replacement information unit instead of the previously established first replacement unit, wherein the second replacement information unit has a bit value opposite the value of the first replacement information unit and the communication device uses the second replacement unit as the second information unit originating from the second data carrier instead of the received information unit.

4. The receiving method of claim 3 , said receiving method further comprising:

receiving all information units originating from the first data carrier until completion after the collision is detected;

generating and delivering a continue command to the second data carrier in a contactless manner, wherein said continue command directs the second data carrier to deliver the second information unit, beginning with an information unit immediately following a previously delivered information unit.

5. A delivering method from a data carrier to a communication device for contactless delivery of identification information of a data carrier through information units, said method comprising:

delivering an information unit;

checking for reception at said data carrier of a first replacement unit after said delivery of the information unit, wherein the data carrier receives said first replacement unit only when a collision occurs;

continuing delivery of a further information unit, wherein the data carrier delivers an information unit immediately following the information unit previously delivered when the data carrier does not receive said first replacement information unit;

and halting the delivery of information units when the data carrier delivers all of said identification information.

6. The delivering method of claim 5 , further comprising:

halting delivery of an information unit, wherein the data carrier halts delivery of the information unit immediately following the information unit previously delivered when the data carrier receives a first replacement information unit and said first replacement information unit is not identical to the previously delivered information unit.

7. The delivering method of claim 6 , wherein the data carrier continues delivering the information unit after reception of a continue command from the communication device, said delivery beginning with the information unit immediately following a previously delivered information unit.

8. A communication device circuit designed for contactless communication with a data carrier storing identification information, the communication device circuit comprising:

receiving means for receiving a received information unit, wherein said communication device circuit uses said received information unit as a first information unit carrying a portion of a first identification information from a first data carrier;

detecting means for detecting a collision of two different information units with two different values, wherein the first information unit originates from a first data carrier and a second information unit originates from a second data carrier and the communication device circuit transmits a first replacement unit only when said collision is detected;

replacing means for replacing the received information unit with the first replacement information unit established by the communication device circuit to be used by said communication device circuit as the first information unit from the first data carrier when the collision is detected; and

delivering means for contactless delivery of the first replacement information unit to at least the first data carrier and the second data carrier only when the collision is detected, wherein said first replacement information unit halts only the second data carrier from continuing delivery of an information unit immediately following the previously delivered second information unit.

9. The communication device circuit of claim 8 , further comprising:

storing means for storing each received information unit prior to the collision as a unit originating from the second data carrier.

10. The communication device circuit of claim 9 , wherein the replacing means are configured to:

replace the first replacement information unit with a second replacement information unit, wherein the communication device circuit uses the second replacement information unit as the information unit originating from the second data carrier instead of the received information unit when a collision occurs.

11. The communication device circuit of claim 10 , further comprising continue command means configured to:

generate a continue command after the collision is detected, and

deliver said continue command,

wherein said continue command restarts the second data carrier delivering the second information unit beginning with the information unit immediately following the previously delivered second information unit.

12. A communication device comprising the communication device circuit of claim 8 .

13. A data carrier circuit designed for contactless communication with a communication device that stores data carrier identification information, the data carrier circuit comprising:

delivering means for delivery of an information unit in a contactless manner; and

checking means for receiving a first replacement information unit established in the communication device after the data carrier circuit delivers said information unit, wherein the data carrier circuit receives the first replacement unit only when a collision occurs at the communication device;

wherein the delivering means continues delivery of the identification information, beginning with an information unit immediately following the previously delivered information unit when the data carrier circuit does not receive said first replacement information unit, and halts the delivery of information units when the data carrier circuit delivers all of the identification information.

14. The data carrier circuit of claim 13 , further comprising:

means for halting delivery of the identification information when the data carrier circuit receives a first replacement information unit that is not identical to the previously delivered information unit; and

storing means of a position immediately following the previously delivered information unit.

15. The data carrier circuit of claim 14 , further comprising:

receiving means for receiving a continue command from the communication device;

detecting means for detecting said continue command; and

continuing means for delivering an information unit immediately following the previously delivered information unit after detecting a continue command.

16. A data carrier comprising the data carrier circuit of claim 13 .