Institut für Hochfrequenztechnik und Elektronik (IHE)

Reconfigurable Antennas for Automotive MIMO

Target of this long term research project is the development of concepts for compact reconfigurable MIMO antenna systems for mobile applications. In this particular case antennas, taking into account the channel information and the environment, should automatically adjusts the optimal radiation characteristics. The optimal directivity pattern are established a priori based on the channel simulation and measurement results. Due to the use of reconfigurable techniques and MIMO technology the outage capacity can be decreased and at the same time the channel capacity can be increased. The interaction of the reconfigurable antennas with the environment can be described by the time-variant, as well as the frequency- and direction-selective characterization of the transmission channels. Based on these information the parameters and methods can be derived to on the one hand establish the performance of the system (for example, the MIMO capacity) and on the other hand compare and optimize different systems in the same environments. Typical mobile applications that are to be addressed are vehicle antennas or antennas for mobile phones.

One of the projects on this topic realized by IHE was KoAMo project. It was cooperation between IMST GmbH and CAU Kiel and KIT, and was supported by German Federal Ministry of Education and Research (BMBF). The task of IHE in this project was examination of system concepts for reconfigurable MIMO antenna systems. It was done based on extensive radio channel simulation. The particular challenge of this task was the large number of degrees of freedom (the number and arrangement of these antennas, application scenarios, frequencies and directional characteristics).

Aerial view of the test route with the channel capacity of a 2×2 MIMO system calculated from measured data
MIMO antenna prototype
Fabricated prototype of a pattern reconfigurable MIMO antenna for automotive applications.
CDF plot measured
CDF plot of the channel capacity calculated from measured data for the reconfigurable multiple antenna system and the two monopoles.

Publications


Design Method for Capacity Enhancement of Pattern-Reconfigurable MIMO Vehicular Antennas [in press].
Kowalewski, J.; Eisenbeis, J.; Tingulstad, M.; Kollar, Z.; Zwick, T.
2019. IEEE antennas and wireless propagation letters, 1. doi:10.1109/lawp.2019.2943205
A low-profile pattern reconfigurable antenna system for automotive MIMO applications.
Kowalewski, J.; Atuegwu, J.; Mayer, J.; Mahler, T.; Zwick, T.
2018. Progress in electromagnetics research, 161, 41–55. doi:10.2528/PIER18010914
Channel Measurement Based Antenna Synthesis for Mobile Automotive MIMO Communication Systems.
Mahler, T.; Kowalewski, J.; Nuß, B.; Richt, C.; Mayer, J.; Zwick, T.
2016. Progress in electromagnetics research / B, 72 (1), 1–16. doi:10.2528/PIERB16081502