The critical importance of accurate channel modelling for the success of mmWave 5G

The move of cellular communications from existing frequencies predominantly below 3 GHz up to the lower end of the mmWave bands around 28 GHz and higher, is set to change everything about how we design, test and operate such systems. The successful launch of a new radio (NR) access system is critically dependent on a correct understanding of the quasi-optical propagation behaviour of narrow beamwidth mmWave signals. The development of accurate channel models will correctly inform the NR specifications and equipment design, then finally the test requirements. However there is not yet consensus across these four domains on key parameters such as the number of usable beams, their angular width and their dynamics in terms of spatial consistency, power, time dispersion and frequency dependency. This paper explains the need to make coordinated progress across the industry to ensure a timely and technically successful deployment of mmWave 5G.