5G Fronthaul Backhaul

Fraunhofer HHI is working on synchronized Ethernet based fronthaul and backhaul solutions for 5G. Unlike with 4G LTE, the signals of 5G are generated and detected in a central unit (CU) or in the cloud. This renders it necessary to have the option of transmitting them over several network nodes. Very high synchronization requirements must be met for interference suppression in mobile communications. A recently developed prototype is able to transmit data with up to 2.5 Gbit/s error-free in a synchronized 5G scenario.


  • Ethernet-based fronthaul for 5G
  • Transmission of 5G central unit (CU) data to distributed unit (DU)
  • Clock propagation via Ethernet (deviation at DU < 0.5 ppb)
  • 2.5 Gbit/s real-time data rate for prototype


  • Baseband transceiver for mm-wave transmission
  • Synchronized 5G fronthaul/backhaul link
  • De-multiplexer for multiple 5G carriers