Spectral coexistence of candidate waveforms and DME in air-to-ground communications: Analysis via hardware software co-design on Zynq SoC

Abstract

Recently, L-band (960–1164 MHz) digital aeronautical communication system (LDACS) has been introduced to meet spectrum requirements of exponentially increasing air-traffic. Compared to its predecessor, LDACS offers wider bandwidth and adopts multi-carrier waveform approach enabling multiple transceivers to coexist with legacy signals in L-band, thereby providing wide variety of services ranging from data to multimedia. This paper offers detailed performance and complexity analysis of various candidate waveforms for LDACS on Zynq System on Chip (ZSoC) platform, consisting of programmable logic (PL) such as FPGA and processing system (PS) such as ARM. The first contribution is the implementation OFDM based LDACS transceiver on ZSoC. Various configurations of the architecture are realized by dividing it into two sections, one for PL and other for PS. We demonstrate the flexibility offered by such co-design approach to decide which part of the transceiver to implement on PL and which on PS to meet the given area, delay and power constraints. The second contribution of this paper is to replace OFDM with windowed and filtered versions of OFDM. Detailed experimental results demonstrate the trade-off between these waveforms with respect to parameters such as out-of-band attenuation, area, delay and power requirements.