Radio Frequency Identification (RFID) is a short range radio technology for communication between two objects namely, a reader and a tag. Design of an RFID tag with the best range is always the motive of an RFID designer. This book discusses the design of two RFID tags with the simulation and measurement results. The first tag is a semi-passive RFID tag, which the user can program and further extend the use of this tag according to the requirements. This RFID tag is provided with JTAG interface for programming and debugging purposes. The read range of this prototype tag is found to be 1m with reader EIRP of 30dBm. The second design is a passive tag which can be commercialized. It achieves a competitive read range of 2.9m for reader EIRP of 21dBm. The read range when measured in a practical implementation inside a building corridor was 15m.