Erik Westerberg

Photonics for radio access networks

In this work we analyse radio access networks (RAN) deployments from the capacity and cost points of view. We find that in order to support the new radio (NR) with system bandwidth of 800MHz and reduce the number of fibre connections between NR and baseband units (BBU) one can use dense wavelength division multiplexing (DWDM), pulse amplitude modulation (PAM4) or multicore fibre. We also find that spectrum and site are the most costly factors in a wide-area RAN deployment and we propose optical solutions to cope with this cost: a) advanced antenna solutions to improve uplink and downlink and downlink performance (throughput and coverage) by means of optical beamforming with silicon photonics phase shifters, or microstructural optical fibres; b) reducing footprint by means of silicon photonics; c) increasing capacity per site exploiting ultra dense WDM transceivers, PAM4 transceivers, multicore fibre.