System Information Distribution in Massive MIMO Systems

by Simon Sörman

Institution: Linköping University
Year: 2016
Keywords: massive MIMO; MIMO; broadcast; beamforming; system information; Engineering and Technology; Electrical Engineering, Electronic Engineering, Information Engineering; Communication Systems; Teknik och teknologier; Elektroteknik och elektronik; Kommunikationssystem; Communication Systems; Examensarbete i Kommunikationssystem
Posted: 02/05/2017
Record ID: 2077904
Full text PDF: http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-129294


The 5th generation mobile telecommunication system (5G) is currently being specified and developed, with large expectations on throughput and efficiency. While 4G and more specifically LTE might constitute a basis of the design of the network, there are some parts that should be improved. One thing to improve is the static signalling that occurs very frequently in a 4G network, of which system information such as synchronization signals, detection of network frequencies, operators, configurations etc. is a part. It has been shown that the static signalling requires both much energy and time-frequency resources. Since the system information is not intended for a single user it is always broadcast so that any user, and any amount of users can read it when needed. 5G will use a technique called massive MIMO, where the base station is equipped with a large number of antennas which can be used to direct signals in space, called beamforming. This thesis presents a new method for distribution of system information that can utilize the beamforming capabilities of massive MIMO. A simple model together with simulated user channel statistics from urban 4G scenarios are used to show that the new method outperforms the classical method of only broadcasting the information, with respect to time-frequency resources. Especially if there are high requirements on the latency of the system information, the new method results in a large gain.