Terabit Optical Feeder Links for DVB Satellite Systems: Real-time End-to-End Communication System Design & Field Test Results

This paper presents the design and field test results of a real-time communication system for the transport of DVB signals over optical feeder links (OFLs). The design relies on 1. multiplexing and massive parallel processing to get to Tbps datarates, 2. error correction in combination with DDR-based interleaving to mitigate the effects of turbulence-induced fading, 3. careful selection of coding rate and interleave depths to minimize latency and 4. ensuring that the OFL-induced degradations on the end-to-end performance are negligible such that the usual suspects – the RF user downlink and the RF amplifier – remain the limiting factors. To verify the system performance, a ground-to-ground test has been conducted over 9.8 km. During the field tests we experienced strong turbulence-induced fading causing about 20 dB of fading penalty (at 1% outage probability). However, as we show in the paper, by properly choosing the coding, coding rate and interleaving depth we can achieve 10 dB in coding and diversity gain (at a BER of 1E-6). With the proposed real-time system, we demonstrate the transmission of DVB signals, in particular 16APSK 9/10 using a 28 Gbps/wavelength OFL with wavelength division multiplexing (WDM). With the presented results, we aim to pave the way to actual OFLs fueling the next generation of very high throughput satellites and constellations.