  L-band Digital Aeronautical Communication System type-1 (L-DACS1) is an
emerging standard that aims at enhancing air traffic management (ATM) by
transitioning the traditional analog aeronautical communication systems to the
superior and highly efficient digital domain. L-DACS1 employs modern and
efficient orthogonal frequency division multiplexing (OFDM) modulation
technique to achieve more efficient and higher data rate in comparison to the
existing aeronautical communication systems. However, the performance of OFDM
systems is very sensitive to synchronization errors. L-DACS1 transmission is in
the L-band aeronautical channels that suffer from large interference and large
Doppler shifts, which makes the synchronization for L-DACS more challenging.
This paper proposes a novel computationally efficient synchronization method
for L-DACS1 systems that offers robust performance. Through simulation, the
proposed method is shown to provide accurate symbol timing offset (STO)
estimation as well as fractional carrier frequency offset (CFO) estimation in a
range of aeronautical channels. In particular, it can yield excellent
synchronization performance in the face of a large carrier frequency offset.
