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.
The DSS team looks back on a very interesting and also very successful year. We would like to thank all who have contributed to that: our students that did or do their Bachelor or Master theses with us, our Hiwis, all cooperation and project partners, all people who helped in educational or adminsitrative manner and of course all those that are not mentioned before. Last but not least: very special thanks to all the PhD students that "tranform" a group of very clever and nice people to a really great team ("vom Besten das Besondere").
We hope that all of you will have a nice Christmas celebration, that you will enjoy the few days that are usually free of work and that you have also a good start into the new year. Let's see what 2018 will bring to us.
On November 24th, one of our DSS team members, Owe Wisch, took part in the "Jugend forscht Perspektivforum" at the CAU. Thirty young students from the "Jugend forscht" project came to Kiel and participated in three different workshops focusing on career paths in maritime climate protection. Owe Wisch from our chair lead one of the workshops and presented his research topics, beamforming techniques and his career decisions so far to the students aged between 16 and 20 years.
We hope that we were able to show the students interesting career paths, share our knowledge about digital signal processing and its applications and hopefully some of them will consider studying electrical engineering, maybe even here in Kiel. We believe that exchange of ideas with the next generation of students, who are interested in science, is very important to the university and our chair and we would like to thank "Jugend forscht" for this opportunity.
Last Thuesday (21.11.2017) we put our first DSS boat for the first time into water. Even if it is not yet christened (to be done soon), we will call it "MISSy". This is an acronym standing for MIMO-SONAR System (thanks to Alexej for creating that name).
MISSy was able to carry three of us and until now we don't have an engine, meaning that we drive it as a bike with muscle force. However, everything was o.k. with MISSy. Now, we will extend it in several ways over the winter time. Our next steps will be an extension for our trailer, as well as artifical SONAR targets, communication and localisation possibilities.
We would like to thank our colleaques from the WTD 71 / FWG for finding an appropriate boat for our purposes and also for their "helping hands".
Recently, Owe Wisch finished his master thesis on speech recognition for swimming googles. The idea was to recognize commands such as "play", "stop", or "pause" while wearing an MP3 Player within the water.
In order to achieve that goal, Owe Wisch added several microphone within and on the outside of typical swimming googles. He used a GMM-based recognizer to map the "bubbling speech" onto several commands. The playback of was done via so-called bone conduction speakers that were also mounted on the side of the googles.
Special thanks to Jonas Wilinski who created the video that you can find below.
This fall Jens Reermann left the team after finishing his defense (see last news entry). At the same time - meaning in October/November - three new people entered our team.
Rasool Al-mafrachi was the first one. He came over from Bagdad / Irak with his family (his wife and his son) in October. Rasool will work on in-car communcation - supporting our speech and audio "division". Afterwards Christin Bald and Owe Wisch joined our team at the beginning of November. Christin will continue the work of Jens (medical signal processing with emphasis on magnetoelectric sensor systems). Owe is our third "underwater guy" - he will focus on communication aspects in SONAR systems.
We are very happy that these three clever, smart, intelligent, ... but also very kind - and that's the important thing - guys joined our group. Welcome to the DSS team.
On Friday, 21st of June, Jens Reermann defended his research on signals processing for magnetoelectric sensor systems very successfully. After 90 minutes of talk and question time he finished his PhD with distinction. Congratulations, Jens, from the entire DSS team.
Jens worked for about three and a half years - as part of the collaborative research center (SFB) 1261 - on all kinds of signal enhancement schemes for the new types of magnetoelectic sensors that are built by the material science researchers here in Kiel and used by our medical colleagues in the universtiy clinicum in Kiel. Jens implemented a real-time system for noise cancellation as well as a digitally contrlled analogue carrier suppression scheme (in cooperation with HF group) - to mention just a few a his contributions.
On June 30st, Chirstin Bald and Thorben Kaak were honored with prices form the Faculty of Engineering. Christin Bald finished as the best bachelor student this year in the study program "Electrical Engineering, Information Technology and Business Management" and Thorben Kaak did the same but in terms of his master studies in the study program "Electrical Engineering".
Of course, the DSS team congratulates both of them to the price and to their excellent performance during the study periods.