News from 2018
On Wednesday the 20th of June, several highschool students of the first senior classes of the Isarnwohld School Gettorf visited the DSS department. Therefore, Prof. Schmidt gave a talk about possible professions for electrical engineers (especially with focus on signal processing) at the Isarnwohld School two days before. So the highschool students could think about the addressed topics and are prepared for the applications shown on Wednesday. At the event on Wednesday first some students of the electrical engineering department talked about the experiences they made during studies and afterwards the doctoral candidates showed some of their work and some demos. We are pretty happy that the Isarnwohld School visited us today and we hoped that the highschool students and the teachers had also some fun visiting us! Special thanks to their very committed teacher, Jan Heidrich.
Prof. Anja Leue from the psychology department of our university organized a lecture series on the topic "language and society". Also the DSS group participated in that event and we presented some of our results on speech in disturbed environments. The lecture took place on Thursday, 5th of May, in one of the lecture rooms in the Audimax building. After the talk, a nice, interesting (and for our field) long discussion took place. Here is the contents of the DSS talk:
Nowadays technical systems allow for voice communication even in very disturbed environments. Examples are communication masks for firefighters, swim googles for under water speech communication or speech communication within cars. In the latter example, the speech of dialog partners is impaired by several factors. Depending on the driving speed, a moderate or even high level of background noise superposes to the speech signals generated by the passengers or by loudspeakers that emit the signals from communication partners connected via mobile phones. Due to the seat adjustment (position and orientation) the front passengers do not speak into the direction of the rear passengers and face-to-face communication among the passengers is not as easy as in a “normal” communication.
If so-called ICC systems (ICC abbreviates in-car communication) are used, the passengers are recorded using microphones. After appropriate signal processing (mainly noise, echo, and feedback reduction) the enhanced signals of the talkers are played back via loudspeakers close to the ears of the listening passengers. At first glance such systems face the same problems as hands-free or speech dialog systems but due to the closed electro-acoustic loop that they have to operate in special problems arise, e.g. correlation of the local signals with the loudspeaker signals that lead to problems when performing system identification with adaptive filters. Furthermore, the enhancement usually leads to a better signal-to-noise ratio at the ears of the listeners. However, the more the signal-to-noise ratio is improved for the listening passengers the more the speaking passengers are aware of or even disturbed by their own voices due to echo perception.
In this talk, I will try to mention most of the challenges that one faces when building enhancement systems for speech in disturbed environments. The solution to these challenges is usually a “cocktail” of individual processing units where the ingredients are low-delay filterbanks, adaptive structures for system identification, spectral suppression rules, decorrelation schemes, and adaptive mixing approaches. In most cases a compromise between the needs of the talking and the listening passengers has to be found which makes this application a very interesting challenge.
If one combines pure ICC systems with other speech and audio systems in a car such as hand-free, anti-noise, or music playback systems the complexity of the resulting system increases. However, the system components mentioned before can be combined such that they can overcome some of the problems, which is again an interesting challenge.
Let me finally mention that even after decades of great and continuous improvement in speech and audio signal processing the communication of people in highly disturbed environments could still be improved. Thus, speech signal enhancement remains “a rocky road” – to say it with the words of one of the early German speech processing researches.
Also in the week of DAGA but between the 21st to the 23rd March the Biosignals Workshop took place in the protestant monastery of St. Augustine in Erfurt. The topic was innovative processing of bioelectric and biomagnetic signals and was organized by the technical VDE committees „Biosignals“ and „Magnetic Methods in Medicine“. The DSS group (Christin and Eric) participated with two contributions in cooperation with the Physikalisch-Technische Bundesanstalt at the workshop. We would like to thank the committees and the organization team for the great workshop!
On 19th to 22nd March the 44th DAGA conference was held in Munich, Germany with about 1500 participants. The DSS group also participated with 9 contributions and the attendance at the conference.
On the occasion of 150 years TUM it was a double conference together with the GAMM Conference of the Society of Applied Math and Mechanic.
Topics like machine learning for speech diagnostics, evaluation of speech communication systems, detection and tracking for SONAR systems, underwater acoustics, anti-noise systems for firefighter helmets, speech perception using an ICC system, head-orientation estimation in motor vehicles and deep learning for bandwidth extension were presented and discussed.
We would like to thank the organizing teams for a great conference.
The 62th German Society for Clinical Neurophysiology and Functional Imaging (DGKN) conference was held in Berlin with about 1778 participants on 15th to 17nd March. Eric (DSS group) and Franziska Weitkamp (Department of Neurology, UKSH) also participated with one Poster and the attendance at the conference. We presented a new electrical approach to optimize the diagnostic specificity. We presented multichannel electric nerve conduction studies in combination with ultrasound, which resulted in a finer grained functional-spatial characterization of the nerve. We would like to thank Prof. Schulte-Mattler (Dept. of Neurology, University of Regensburg) for a great discussion regarding our CRC-Project and for all further support.
Beside the DGKN conference it was a very nice and enjoyable time with all other PhDs of the Department of Neurology. Special thanks to PD Dr. Helmut Laufs (Department of Neurology, UKSH) for organization of the complete trip.
Since January this year we have two new PhD students in the team: Elke Warmerdam and Finn Spitz.
Elke is from Amsterdam and she works in the neurology department in the university hospital in the group of Prof. Maetzler. Her research topic is movement analysis of patients with neurologic disorders. Elke cooperates with us in signal processing related aspects of her research. Elke plays volleyball and goes everywhere by bike.
Finn is working on speech analysis and therapy improvement for Parkinson patients. In his research hearing aid devices are of specific importance. Finn is a motorbike rider (Kawasaki ER6F) and does karate since about 10 yeas.