Debate continues to rage about the 5G air interface – will the new generation of mobile networks require an entirely new air interface, or several; or will it rely on evolutions of current OFDM technologies; or be primarily an umbrella framework tying different options together seamlessly and flexibly according to use case? The choices, and the companies supporting them, will become clearer as the standards process gets into gear, but it is a brave company which tries to propose such a fundamental element of 5G, if it is not one of the inner circle of giants. That is what start-up Cohere is aiming to do, however, and is likely to find itself up against Qualcomm (the most public about its…