Antenna and packaging for 5G Multiple-Input and Multiple-Output (MIMO) Systems

Master Thesis:
Antenna and packaging for 5G Multiple-Input and Multiple-Output (MIMO) Systems

The ever increasing demand on high data rate wireless communication leads to the evolution from the 4G to 5G system in mobile networks. The MIMO or Massive MIMO are believed to be capable candidates for the architecture of the 5G mobile networks, in which quite a few of issues are involved like the channel modeling, circuit design, antenna design, system integration and packaging. The design of antenna as well as the interface between antenna and circuit is influential on the system’s performance. This thesis focuses on three aspects within the 5G MIMO:

(1)    Antenna design. Antennas with a functional frequency at 30 GHz with specified bandwidth, radiation patterns and gain shall be designed, fabricated and tested under the considerations for satisfactory performance, easy integration with the circuits and low cost.

(2)    Integration between the antenna and the circuit. The loss and bandwidth of the interface between the antenna and the circuit is usually a determining factor for the whole link budget and system’s bandwidth. Traditional interconnections of wire-bonding and flip-chip shall be studied within this thesis to provide an optimum solution. 

(3)    System packaging. Package shall be designed to protect the highly-integrated system from environmental interference. When designing the package, consideration shall be taken upon the problem of Electromagnetic Compatibility (EMC) and heat radiating. The EMC within the system might have influence on the antenna’s performance, while the heating would cause physical tension in the junction between the antenna and circuit. As a result, design of the system package is usually conducted under a macroscopic view.    

Objectives: The candidate will investigate such a layer stack with respect to materials, thermal expansion coefficients, manufacturability, and modeling. Models will be created, taking into account both thermal heat conduction, as well as electromagnetic effects, to guarantee the final stack will function as expected. Furthermore a layer-stack will be constructed, measured at mm-wave frequencies and compared to the created models.    

Fig. 1. Illustrates a potential layer stack for complete wafer-level packaging for mm-wave integrated circuits and antennas, containing substrate layers with active devices, for example silicon, but also interconnecting layers as well as antennas. Note that proper care has to be taken to remove the dissipated heat from the active devices towards a heatsink. Also note that many interactions between the different layers may take place, which need to be taken into account in the design of the complete stack.

Contact for more information: Christian Fager,

Published: Fri 19 Dec 2014.