Random access procedure in Non-Terrestrial 5G Networks

The goal of non-terrestrial networks (NTN) is to complement terrestrial 5G networks by providing enhanced coverage and service continuity for unserved areas of 5G terrestrial networks. One of the pivotal factors in the effective deployment of mobile satellite systems in the 5G network is to maximize the utilization of the current technology in terrestrial systems, to lower the implementation costs. The efficient design and integration of NTN to 5G systems depend on the consideration of some unique features of satellite communication systems, such as large propagation delays and large Doppler frequency shifts. Specifically, geostationary earth orbit (GEO) communication satellites experience large propagation delays, while low earth orbit (LEO) communication satellites are prone to large Doppler frequency shifts due to the fast mobility of LEO satellites and/or user equipment (UE). These factors affect some of the currently used algorithms of the radio access network (RAN) of terrestrial 5G systems. Specifically affected is the random access channel (RACH). This work will focus on the analysis, assessment and improvement of Physical Random Access Channel (PRACH) in (5G) to be adopted for (NTN), the implemented work is comprising of AWGN channel, RACH transmitter, which doesn't have a big challenge as the case of RACH receiver regarding the detection with the satellite impairments. Hence, the work focused on the receiver performance in two different scenarios: Near GEO Sat and LEO Sat.