IEEE 802.15.4 is a wireless network for low power, low rate and low cost. So, Transmit center frequency tolerance is ±40ppm at 2.4Ghz in the standard.
To be robust against frequency offset, noncoherent detector is used. Estimator that recovers frequency offset (±80ppm at 2.4Ghz) and symbol timing jointly, is proposed.
Digital baseband processor including those noncoherent detector and estimator is designed for IEEE 802.15.4 2.4Ghz PHY layer.
The digital baseband processor shows $\frac{E_b}{N_o}=14dB$ at Packet Error Rate $10^(-2)$
