Gerhard Bauch, head of the Institute of Communications, has been elevated to the grade of Fellow of the Institute of Electrical and Electronics Engineers (IEEE).
IEEE is the world's largest professional association dedicated to advancing technological innovation and excellence for the benefit of humanity. IEEE and its members inspire a global community through IEEE's highly cited publications, conferences, technology standards, and professional and educational activities.
The IEEE grade of Fellow is one of the most prestigious honors of the IEEE, and is bestowed upon a very limited number of Senior Members who have made outstanding contributions to the electrical and information technologies and sciences for the benefit of humanity and the profession. The number of IEEE Fellows elevated in a year is no more than one-tenth of one percent of the total IEEE voting membership.
IEEE honors Gerhard Bauch’s contributions to iterative processing in multiple-input multiple-output (MIMO) systems.
Wireless digital communications (mobile communications, WLAN etc.) has grown at amazing rates since the 1990s. In particular, the big success of smartphones requires reliable transmission of ever more data volumes at always higher speed. Wireless transmission anyway is a big challenge due to shadowing between transmitter and receiver, reflections of the signal at buildings, vehicles and other objects as well as due to the mobility of the users. Moreover, the transmit power is very low.
Two important ingrediants have significantly contributed to making todays multimedia communication possible at all: Error correcting codes and multiple antenna (MIMO) systems.
Error correcting codes allow to correct transmission bit errors which are unavoidable under the severe conditions of wireless transmission. The development of Turbo codes in 1993 has been a milestone in error correcting codes. They perform close to the theoretical limit while having manageable implementation complexity. Today, Turbo codes are standard in many systems, e.g. in LTE. The name indicates the analogy to a turbo engine: An iterative decoding scheme feeds back the not yet fully exploited information from the decoder output to its input in an intelligent way.
This iterative “Turbo principle” can be extended to a variety of other detection problems in a receiver, in particular to MIMO detection.
It is the idea of MIMO to increase the data rate by transmitting simultaneously in the same frequency band additional data from a second antenna. The transmit power is distributed over the antennas such that the total transmit power is not increased.
Todays systems, e.g. LTE or WLAN, use up to four antennas. In research, we now investigate up to hundreds of very small antennas under the keyword “Massive MIMO.”
Both fields, coding and MIMO, are nice examples showing that already quite sophisticated systems can only be further developed with the help of fundamental theoretical understanding. The relevant theory here is “Information Theory” which was initiated by Claude Elwood Shannon in 1948.
For example, it is all but intuitive that transmitting simultaneously from multiple antennas is a good idea. Intuitively, we would assume that the simultaneously transmitted signals will interfere with each other and no information transmission is possible at all. However, information theory shows that MIMO in combination with coding allows for data rates which are significantly higher than what would be possible with a single transmit antenna.
The application of MIMO as standard transmission mode in todays most advanced mobile communications system LTE and many other systems proofs: Unlike a widely spread opinion, there is no fundamental contradiction between theory as taught at universities and industrial practice. Practice is theoretical.