CMOS fully integrated 2.5GHz active RFID tag with on-chip antenna

This paper presents a fully integrated active RFID tag, realized in a 3.3V 0.35μm CMOS process, which exploits an on-chip loop antenna for short-range communications. This solution eliminates the need of a post-process assembled external antenna thus allowing to obtain a low-cost system for RFID applications. The implemented chip uses a 2.5GHz complementary cross-coupled LC oscillator based OOK transmitter. The system is duty cycled for reducing the power consumption. For the transmission of the stored 32bit indentifying code at 5kbit/s data rate, the average power consumption is 160μW. The integrated loop antenna radiates sufficient power for 1m communication range.