Standalone and Non-Standalone Beam Management for 3GPP NR at mmWaves

The next generation of cellular networks will exploit mmWave frequencies to dramatically increase the network capacity. Communication at such high frequencies, however, requires directionality to compensate the increased propagation loss. Users and base stations need to align their beams during both initial access and data transmissions to ensure that the maximum gain is reached. The accuracy of beam selection, and the delay in updating the beam pair or performing initial access, impact the end-to-end performance and the quality of service. In this article we review the beam management procedures included in the 3GPP NR specifications and propose possible enhancements, based on both standalone and non-standalone architectures, to improve network control operations. We also provide a performance comparison among different schemes, along with design insights on the most important parameters related to beam management frameworks.