Verifying dynamic spectrum sharing for 5G NR

This is where DSS comes into play. It introduces smart algorithms and combines several other features that allow the simultaneous coexistence between 4G LTE and 5G NR users in a single mobile network, while using the same frequency band.

In the LTE network, multicast broadcast single frequency network (MBSFN) is activated to allow 5G NR the transmission of synchronisation signal blocks (SSB) and tracking reference signals (TRS). Depending on the amount of LTE and 5G NR users in a specific cell, DSS helps balance the LTE or 5G NR scheduling of mobile devices based on the actual traffic load. That allows the transmission of 5G data in standard LTE subframes, while specific rate-matching techniques are applied that avoid e.g. the always-present LTE cell-specific reference signals (CRS). 

The combination of these features, functions and complex algorithms requires extensive testing of mobile devices. DSS will complement the 5G NR signalling tester feature coverage of Rohde & Schwarz by using the R&S CMX500 5G NR signalling tester together with the company’s tried-and-tested, industry-leading LTE testing solutions, based on the R&S CMW500 mobile radio tester. This will help expedite the smooth integration of the 5G NR technology into existing LTE networks for the worldwide ecosystem, from chipset suppliers, modem and smartphone manufacturers to mobile network operators. 

In close cooperation between the R&D teams of both Rohde & Schwarz and MediaTek, correct implementation of DSS algorithms on LTE and 5G NR has been tested extensively between the R&S CMX500 radio communication tester and MediaTek’s new 5G chipset Dimensity 1000. This verification will enable MediaTek to roll out their chipsets into markets where 5G NR technology is being used within existing LTE band allocations.