METHOD FOR CODING RFID TAGS

摘要

A method is disclosed for coding data communication between an interrogator and electronically coded tags. In the method the data is encoded by an active time period of sub-carrier modulation and an inactive time period of no modulation. In the method a characteristic of the modulation such as phase and/or frequency is varied during the active time period to increase a rate at which the data may be communicated. The method is adapted to minimize collisions between the tags arising from the effect of small signal suppression.