A new transponder architecture with on-chip ADC for long-range telemetry applications

We present a new architecture for wireless power and data telemetry that recovers power and a system clock from a weak incident RF signal. A high-efficiency RF-DC converter generates a 3-VDC supply for the system from a -12.3-dBm incident RF signal, gathered by a commercial 50-Ω antenna. A system clock is extracted from the same incident signal, by an injection-locked LC oscillator. Sub-harmonic injection-locking facilitates the separation of the incident and the transmit signal frequencies, without need for a PLL. The proposed architecture is used in a long-range telemetry device, incorporating an on-chip ADC, and employing active telemetry for data transmission. Data is transmitted through binary phase-shift-keying of a 900-MHz carrier. The prototype, implemented in 0.25-μm CMOS, occupies less than 1 mm². A wireless operation range of more than 18 meters is indicated by anechoic chamber testing.