Coexistence of NR-U operators in multichannel scenarios: Fair cooperation or endless struggle for channel resources

Abstract

The New Radio Unlicensed (NR-U) technology opens the unlicensed spectrum for 5G cellular systems and employs multichannel operation to use the full potential of unlicensed bands. However, the intensive deployment of NR-U systems entails the coexistence issue of cellular operators. The paper studies the coexistence of two NR-U operators with distinct sets of used channels and multichannel methods. It is assumed that an operator has already deployed its NR-U base stations in the U-NII-3 frequency range, and a new operator intends to deploy a new NR-U network in the same range. It is shown that if the new operator solely maximizes its throughput, the performance of the old operator degrades significantly. Such behavior provokes the old operator to change its multichannel method and/or set of channels, thus leading to endless configuration adjustments by both operators. Therefore, the paper formulates several recommendations that provide a fair deployment with high throughput for both operators.