Mobile operator EE teamed up with Qualcomm and Huawei to demonstrate 400Mbps 4G data speeds at Wembley Stadium in London yesterday, ahead of the upcoming launch of what will be its fastest mobile network to date. According to TechWeek Europe, the firms showcased so-called ‘LTE Category 9’ mobile broadband speeds at the event, in which EE also confirmed its intention to extend its ‘4G+’ network – which already offers peak download speeds of 150Mbps – to the iconic football stadium by the end of this month. EE is trialling 400Mbps data speeds by combining three LTE carrier bands: 20MHz of 1800MHz spectrum, 20MHz in the 2600MHz band (which are already aggregated to offer its commercial 4G+ service) plus a further 15MHz of 2600MHz spectrum. The cellco, which has six million mobile subscribers in the UK, launched its 4G+ network in parts of London last October, offering a theoretical maximum download speed of up to 300Mbps. By 2017 it aims to have expanded coverage to the country’s 20 busiest cities via a GBP1.5 billion (USD2.32 billion) three-year investment.