The NG user plane interface (NG-U) is defined between the NG-RAN node and the UPF. The transport network layer is built on IP transport and GTP-U is used on top of UDP/IP to carry the user plane PDUs between the NG-RAN node and the UPF.

NG-U provides non-guaranteed delivery of user plane PDUs between the NG-RAN node and the UPF.

gNB-CU-Control Plane (gNB-CU-CP): a logical node hosting the RRC and the control plane part of the PDCP protocol of the gNB-CU for an en-gNB or a gNB. The gNB-CU-CP terminates the E1 interface connected with the gNB-CU-UP and the F1-C interface connected with the gNB-DU.

The different sublayers used in  Radio Protocol Architecture are: Medium Access Control (MAC), Radio Link Control (RLC), Packet Data Convergence Protocol (PDCP) and Service Data Adaptation Protocol (SDAP), Radio Resource Control (RRC) and Non-Access Stratum (NAS). Where:

-The physical layer offers to the MAC sublayer transport channels;

gNB Central Unit (gNB-CU): a logical node hosting RRC, SDAP and PDCP protocols of the gNB or RRC and PDCP protocols of the en-gNB that controls the operation of one or more gNB-DUs. The gNB-CU terminates the F1 interface connected with the gNB-DU. 

The gNB and ng-eNB host the following functions:

-Functions for Radio Resource Management: Radio Bearer Control, Radio Admission Control, Connection Mobility Control, Dynamic allocation of resources to UEs in both uplink and downlink (scheduling);

MATLAB has introduced its 5G Toolbox, which provides standards compliant waveforms and reference examples for modeling, simulation, and verification of the physical layer of 3GPP 5G New Radio (NR) communications systems. 5G Toolbox can be used  to design algorithms and predict end-to-end link performance of systems that conform to the 5G Release 15 standard.

As the need and dependency on wireless network is increasing, a stronger and faster network is required to cater to the demands of millions. The 5G networks are the next generation of mobile internet connectivity, offering faster speeds and more reliable connections on smartphones and other devices than ever before.

In the blog, the readers will comprehend the elementary aspects of Small cell in 5G communication mechanism, in a way it is enhanced 4G-LTE. The article will be significant to the scholars, learners, researcher and City RF Planner who are aware with 4G, 3G or 2G also be worthwhile for those who are innovative to this technology.