Crystal-Free radios are susceptible to frequency drifts due to temperature and voltage. Compensation for the frequency drift in the 2.4 GHz local oscillator due to voltage variation was demonstrated for a Crystal-Free radio while powered from a solar cell under 200 mW/cm2 of irradiation and a 0805 capacitor. Without compensation the local oscillator frequency would vary by 2.4 MHz while the 802.15.4 packets were transmitted resulting in a loss of 100B of the payload. With frequency drift compensation that oscillator frequency varied less than 300KHz and the full length 125B 802.15.4 packet was received by an off-the-self component radio.
Keywords: Crystal-Free Radio, Frequency Compensation, Local Oscillator, Voltage Variation