A year ago we were writing about the “dream team” for LTE-Advanced – three-way carrier aggregation (3CA), 256QAM modulation and TDD or mixed FDD/TDD spectrum. Now the goalposts have already changed dramatically. 3CA is becoming commonplace and operators like AT&T have promised to start deploying 4CA this year, and now Huawei and Vodafone Romania are already talking about 5CA spanning TDD and FDD. The two companies conducted a demonstration of five-carrier aggregation using an “innovative mix of FDD + TDD”. They achieved speeds of 1.35Gbps over LTE, in a test which also harnessed 4×4 MIMO and 256QAM. About a year ago, Telstra of Australia became the first operator to boast a successful trial of five-carrier aggregation, working with Ericsson to…