An Efficient Data-aided Synchronization in L-DACS1 for Aeronautical Communications

TL;DR

This paper introduces a computationally efficient synchronization method for L-DACS1 aeronautical communication systems, improving accuracy and robustness in challenging channel conditions with large interference and Doppler shifts.

Contribution

It presents a novel synchronization technique that enhances symbol timing and frequency offset estimation specifically for L-DACS1 systems in aeronautical channels.

Findings

Accurate symbol timing offset estimation achieved

Effective fractional carrier frequency offset estimation demonstrated

Robust synchronization performance under large Doppler shifts

Abstract

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.