5G-EmuSat develops a demonstrator platform implementing the physical layer and the necessary parts of the Media Access Control (MAC) layer allowing the detailed analysis of 5G New Radio (NR) for direct transmission and reception via a satellite channel using the open-source Software Defined Radio software OpenAirInterface (OAI) ([1]).

Concept and Methodology

5G-EmuSat develops a demonstrator platform implementing the physical layer and the necessary parts of the MAC layer of 5G New Radio (NR) for direct transmission and reception via a satellite channel using and extending the open-source SDR software OpenAirInterface (OAI).
Previously, the OAI community developed an open-source implementation of the LTE eNB and LTE User Equipment (UE), as well as the LTE Evolved Packet Core (EPC). Currently, parts of the 5G NR gNB and UE components are under development.

The following activities are planned on physical and MAC layers to achieve a working demonstrator platform for 5G NR connectivity over satellite:

• Completing the implementation of all relevant 5G NR channels in OAI: PDSCH, PDCCH, PUSCH, PUCCH, PRACH, SS Block;
• Completing the implementation of the necessary MAC functionalities in OAI: initial timing advance (TA) signaling, TA updates, data connection for a single static user;
• Closely following the 3GPP standardization process especially regarding 5G NR Non-Terrestrial Networks (NTN) and extensions for direct to UE access;
• Implementing the relevant 5G NR NTN direct to UE extensions in OAI, according to the finished 3GPP Study Items on impact areas and solutions for NR over satellites ([2], [3]);
• Functional and performance validation tests of the OAI implementation using a Keysight channel emulator, emulating the satellite propagation channel with long delay;
• Feeding back the code to the OAI repository that has been verified to be NR standard compliant.

Deliverables and Output

• Real time prototype for New Radio adapted to operate over LEO;
• Feedback and contribution to the OpenAirInterface with verified code;
• Technical notes on findings.

Duration and schedule

The duration of the activity is 9 month.

Contracted budget

The activity was contracted with a budget of 59.990.- €.

Contact person

Thomas Schlichter thomas.schlichter(Replace this parenthesis with the @ sign)iis.fraunhofer.de.

References and related activities

[1] OpenAirInterface Software Alliance, www.openairinterface.org

[2] 3GPP TR 38.811 “Study on New Radio (NR) to support non terrestrial networks (Release 15)”, V15.2.0, 2019-09

[3] 3GPP TR 38.821 “Solutions for NR to support non-terrestrial networks (NTN) (Release 16)”, V16.0.0, 2019-12