Lecture "Adaptive Filters"

Basic Information

Lecturers:   Gerhard Schmidt (lecture) and Tobias Hübschen (exercise)
Room:   F-SR III
Language:   English
Target group:   Students in electrical engineering and computer engineering
Prerequisites:   Basics in system theory

Students attending this lecture should learn the basics of adaptive filters. To achieve this, necessary algorithms will be derived and applied to problems arising in speech and audio processing. The algorithms comprise Wiener filtering, linear prediction, and adaptive schemes such as the NLMS algorithm, affine projection, and the RLS algorithm. For applications from speech and audio processing we use noise and reverberation reduction, echo cancellation, and beamforming.

Topic overview:

  • Introduction and application examples
  • Signal properties and cost functions
  • Wiener filter and principle of orthogonality
  • Linear prediction
  • RLS algorithm
  • LMS algorithm and its normalized version
  • Affine projection algorithm
  • Control of adaptive filters
  • Efficient processing structures
  • Applications of linear prediction



The exam dates have been set. There are a total of five dates available from July until September. Also remember to sign up for a talk as this is a prerequisite to sit the exam.



Lecture Slides

The slides of the lecture can be found here.



  Extension for the lecture "Wiener Filter"
(derivation of the error surface)


Matlab Demos

  Matlab demo (GUI based) for adaptive system identification
  Matlab demo (GUI based) for adaptive noise suppression
  Matlab demo (GUI based) for linear prediction
  Matlab demo (GUI based) for the NLMS algorithms
  Matlab demo (GUI based) for prediction-based filter design



The first exercise will be on 04.05.2018 at 8.15 h in F-SR III. Please prepare by reviewing the topics Wiener Filter and Linear Prediction.

The second exercise will be on 01.06.2018 at 8.15 h in F-SR III. Please prepare by reviewing the topics Algorithms and Control.

At the end of the semester, each student will give a talk about a certain topic as a prerequisite to sit the exam. The aim is both to give you the chance to work on an adaptive filter-related topic that interests you, and to improve your presentational skills. The talks should take ten minutes, plus 2.5 minutes of discussion and 2.5 minutes of feedback.

Please contact This email address is being protected from spambots. You need JavaScript enabled to view it. with your topic suggestion. Below you can find the current schedule of the talks.

Date   Room   Time   Topic   Presenter(s)
22.06.2018   F-SR III   08:20 h   Active Noise Control in Headphones   Fynn Kamrath
22.06.2018   F-SR III   08:35 h   Adaptive Filters in Hearing Aids   Sreejith Gopakumar
22.06.2018   F-SR III   08:50 h   Adaptation of Neural Networks   Erman Kalpakçı
22.06.2018   F-SR III   09:05 h   Nonlinear Echo Cancellation   Claudius Karnstädt
22.06.2018   F-SR III   09:30 h   ROSE-Filter for Radar Tracking   Fabian Heuer, Simon Helling
22.06.2018   F-SR III   09:55 h   Filtered-X LMS Algorithm   Tobias Seide
22.06.2018   F-SR III   10:10 h   Adaptive Filters in Retinal Implants   Patricia Piepjohn
22.06.2018   F-SR III   10:25 h   Adaptive Beamforming   Joscha Schaumburg, Karl Heger
29.06.2018   F-SR III   08:20 h   Noise Cancellation in ECG Signals using Adaptive Filters   Malte Wrobel
29.06.2018   F-SR III   08:35 h   Nonlinear Equalization   Nico Simoski
29.06.2018   F-SR III   08:50 h   Adaptive Image Filters to Suppress Noise   Ali Hadidi, Ayman Soukieh
29.06.2018   F-SR III   09:15 h   MPEG Audio Coding   Anton Lösch
29.06.2018   F-SR III   09:40 h   Phased Locked Loop using Adaptive Filters   Gyde Carstens, Tim Benedikt Kupke
29.06.2018   F-SR III   10:05 h   Adaptive Filters in Military Applications   Christian Olsiewski
29.06.2018   F-SR III   10:20 h   GSM Source Coding   Max Timmermann
29.06.2018   F-SR III   10:35 h   Signal Prediction   Gerrit Oldenburger, Egzon Miftaraj




Below is the list of students with their exam dates. If you do not have a date for the exam yet please register in the online booking system. You can find the booking system here.

Date   Time   Students (matriculation numbers)   Assessor
20.02.2019   09:30 h   1133   Tobias Hübschen


Website News

30.11.2018: New student project on driver distraction added.

01.10.2018: Dissertation of Philipp Bulling added.

14.08.2018: New section about our SONAR "sisters" added.

18.07.2018: New section about our Parkinson voice training game added.

07.07.2018: New lecture Fundamentals of Acoustics by Jan Abshagen added.

Recent Publications


J. Reermann, E. Elzenheimer and G. Schmidt: Real-time Biomagnetic Signal Processing for Uncooled Magnetometers in Cardiology, IEEE Sensors Journal, January, 2019 (early access, doi:  10.1109/JSEN.2019.2893236)


Prof. Dr.-Ing. Gerhard Schmidt

E-Mail: gus@tf.uni-kiel.de

Christian-Albrechts-Universität zu Kiel
Faculty of Engineering
Institute for Electrical Engineering and Information Engineering
Digital Signal Processing and System Theory

Kaiserstr. 2
24143 Kiel, Germany

Recent News

Saturday Morning Physics 2018

The DSS team was invited to participate in the last of the "Saturday Morning Physics" (SMP) events in 2018. On December 8th, a Saturday of course, Thorben Kaak, Gerhard Schmidt, and Owe Wisch gave a talk on underwater signal processing. Pupils from all around Schleswig-Holstein were quite interested, especially in the basics of SONAR systems.