Contact Persons
Gunnar Bark +46730435104
gunnar.bark@ericsson.com
Master Thesis – Massive MIMo in 5G
Background
Ericsson and other mobile network vendors are currently standardizing 5G New Radio in the global standardization body 3GPP. 5G should provide tenfold performance increase in terms of user bit rates, end-to-end delays, system capacity, and energy performance compared to current 4G systems.
In order to achieve these ambituous targets, advanced multi-antenna technology is crucial. In 5G, there will a larger amount of antenna elements in both the base-station and the mobile terminal. This is called Muliple Input and Mulitiple Output (MIMO) technologies. Radio transmission beam-forming with many antennas exists already in 4G.
However, in 5G, we expect a relatively new form of MIMO technology to break through, namely Massive MIMO.
In massive MIMO, the transmitted radio energy is focused to the specific position, where the intended mobile terminal is. This is achieved by adding the received signals from the numeruous base station antennas coherently in the mobile terminal. This results in very good signal-to-noise ratio for the intended mobile, while mobiles at other positions are not interfered. With enough base station antenna elements, one can actually transmit concurrently to multiple mobiles in the same cell, which of course increase system capacity.
Thesis Description
While the single cell performance of Massive MIMO is quite well understood for relatively ideal models, there are radio network algorithms to be further investigated and optimized for more realistic multi-cell scenarios. The purpose of this thesis is to propose and evaluate Radio Resorce Management (RRM) algorithms for Massive MIMO in 5G.
Of specific interest is how to aquire channel state information, crucial for gaining the benefits of Massive MIMO, and how to handle effects of the lack therof. In Massive MIMO, the base station estimates the radio channel by measuring how a known pilot signal, transmitted from the mobile, is transformed by the inherent multi-path propagation of the radio channel. However, if the mobile is out-of-coverage, the pilot does not help the base-station and other methods to do the transmission beam-forming in the base station, or alternatively increase the coverage, needs to be investigated. Another interesting problem is how to allocate the unique pilot signals to each mobile. If time allows, the thesis will also investigate methods to select modulation and coding format, i.e. link adaptation, for the base station transmission with limited pilot reception quality.
Contact Persons
Gunnar Bark +46730435104
gunnar.bark@ericsson.com
Qualifications
This project is aimed at Master of Science students in mathematics/statistics, computer science or electrical engineering. Matlab, C and JAVA are our primary tools for simulation so practical background with these is preferred. Successful candidate has a solid knowledge in radio communication and has average grade above B/4.0.
Extent
This position is for one student. Scope is for 30 university points (Swedish högskolepoäng)
Location
Ericsson AB Mjärdevi, Linköping
Preferred Starting Date
January 2018
