The feasibility study for the essential RF components and sub-systems for an FR2-1 multi-band system were carried out and found that:

• Multi-band implementations with percentage BW of up to 19.5% are feasible.
• Multi-band implementations with greater percentage BW's may be feasible in the future.

Within these percentage BWs some design blocks such as the PA, and RF front end components are capable of true multi-band performance, other blocks and specifically the phase shifters used for beam forming the different bands need to be applied to separate band specific solutions. There are currently no proposed solutions to enable a wide band beam former to steer beams for different bands in different directions. Antennas and antenna arrays are limited to certain maximum percentage BW's however MB solutions using multiple antenna arrays have been investigated and solutions within the agreed percentage BW's above have been identified. Other considerations, i.e. on a need of DPD and complications of digital and analogue designs for a wideband / multiband BS are also analysed. Considering the wide range of FR2-1 operating bands and potential combinations FR2-1 operating bands have been considered within frequency groups with limited percentage BW's as shown in Table 5.1-1 and feasibility analysed within these groups. However, whilst practical limits exist which may limit multi-band solutions to be within these groups no restrictions need to be used in the technical specification and as such frequency groups do not need to be defined with the updates of the technical specifications. On the other hand, as highlighted in clause 6.2 study of solutions across frequency groups may be further studied and the use of additional multi-band requirements may be considered in the future for percentage BW's greater than 19.5%. For updating the technical specifications, FR2-1 multi-band requirements are to be added to the existing NR TS 38.104 and TS 38.141-2 technical specifications, using the same approach as FR1 multi-band as described in clause 6. The existing MB RIB definition as well as the explanations on BS capable of supporting operation in multiple operating bands with different implementations at the RIB in TS 38.104 for FR1 can also apply to FR2-1.