With a highly-connected world where fast Internet access is vital, ZTE has pushed the envelope a little further with its pre-5G concept shared at LTE World Summit 2014 in Nice, France.
It has announced that under certain conditions, some 5G technologies can provide a 5G-like user experience on 4G terminals without changing the air interface standards.
“With next-generation 5G technologies being deployed in 2020, there were industry concerns over what technologies will be used in the next six years. To address this, ZTE proposes to apply some of the 5G technology on top of 4G to meet users’ requirements,” said Dr Xiang Jiying, CTO of wireless products at ZTE.
For example, with Massive MIMO the reference codes, such as the CSI-RS (channel state information reference signal) should be modified to support hundreds of antenna ports, and the terminals should also be modified for the feedback of hundreds of PMIs (Pre-coding Matrix Indicator).
However, in TDD (time division duplex) mode, the symmetry of uplink and downlink channels can be used for channel estimation. Although without feedback channels, the accuracy of channel estimation even exceeds thefeedback result. Another example is inter-site interference cancellation in UDNs (user densification network). The interference can be decreased effectively through ZTE’s sophisticated 4G Cloud Radio architecture, i.e dynamic local mesh networks, and the R12 on/off technologies.
In addition, ZTE has invested heavily in the development of 4G vector processing chipsets, which have extensible software architecture and can meet pre-5G requirements by modifying software instruction sets rather than changing hardware.