Dear subscribers of the colloquium newsletter,
we are pleased to announce the next date of our Communication Technology
Colloquium:
*Wednesday, June 23, 2021*
*Speaker:* Markus Tilichi
*Tim*e: 11:00 a.m.
*Location*:
https://rwth.zoom.us/j/97904157921?pwd=SWpsbDl0MWhrWjY1ZkZaeFRoYmErZz09
Meeting-ID: 979 0415 7921
Passwort: 481650
*Master-Lecture*: Enhanced Own Voice Perception for Hearables Using
Machine Learning
Modern headphones implement sophisticated signal processing and control
algorithms to improve the user’s hearing and listening experience.
Especially new generation in-ear headphones, so-called hearables,
integrate these technologies, such as active noise control, on a large
scale. A remaining issue with hearables is the sound degradation
introduced through sealing the ear canal. This degradation is called the
Occlusion Effect. It is often described as boomy and hollow perception
of the speaker’s own voice. While Active Noise Cancellation reduces
ambient noise, the Occlusion Effect still persists. In order to improve
the speaker’s own voice perception and alleviate the Occlusion Effect,
it is required to play back some of the voice signal without amplifying
ambient noise.
In this thesis a novel approach for selective hear-through based on deep
neural networks is investigated. Integrated into a feed-forward ANC
topology the proposed neural network utilizes ambient and in-ear
microphone signals for an estimation of the speaker’s own voice. Speech
samples for both microphone signals were simulated through augmentation
of the DARPA TIMIT speech corpus. This included virtually occluding the
samples for one channel and adding real-world noise samples to the
other. The proposed network was found to reduce ambient noise from the
test dataset to a barely audible extent. Metrics for quality and
intelligibility suggest superior denoising performance in comparison
with one channel network benchmarks. Despite the relatively small
training dataset, the network may also regularize well when trained with
measurement data.
All interested parties are cordially invited, registration is not required.
General information about the colloquium, as well as a current time
scale of the Communication Technology Colloquium can be found at:
https://www.iks.rwth-aachen.de/atktuelles/kolloquium
--
Irina Ronkartz
Institute of Communication Systems (IKS)
RWTH Aachen University
Muffeter Weg 3a, 52074 Aachen, Germany
+49 241 80 26958 (phone)
ronkartz(a)iks.rwth-aachen.de
http://www.iks.rwth-aachen.de/
Dear subscribers of the colloquium newsletter,
we are pleased to announce the next date of our Communication Technology
Colloquium:
*Monday, June 21, 2021*
*Speaker:* Henning Niendieck
*Time:* 2:00 p.m.
*Location*:
https://rwth.zoom.us/j/97904157921?pwd=SWpsbDl0MWhrWjY1ZkZaeFRoYmErZz09
Meeting-ID: 979 0415 7921
Passwort: 481650
*Master-Lecture*: Optimized Design of an Acoustic Front-End for Active
Noise Cancelling Headphones
Headphones with active noise cancelling (ANC) capability become more and
more common in everyday life. The acoustic front-end, consisting of the
headphone enclosure, a speaker and at least two microphones, is a
crucial part of the ANC system. It significantly influences the
achievable degree of noise cancelling. The optimization of the acoustic
front-end is therefore a key factor for a high ANC performance. Being
able to completely predict the influence of every element of the
acoustic front-end is a desirable goal.
This work comprises an investigation of the different components of the
acoustic front-end. It includes the characterization of a set of
microphones to evaluate the influence on the ANC performance. A
development of a model of the electro-acoustic system of a headphone
enclosure with an integrated dynamic speaker allows the simulation of
relevant transfer paths. Every individual element of the enclosure is
modeled, so that the effect of every parameter on the transfer paths can
be investigated. This provides a great advantage over investigations on
the basis of measurements. A comparison of the boundary element method
and lumped element method shows their suitability for acoustic modeling.
The inability of the used implementation of the boundary element method
to directly model viscothermal losses exhibits limitations, as these
losses play an important role in the acoustic front-end. A 3D print of
the prototype allowed the verification of the acoustic model with
measurements. The different enclosure design parameters with regard to
ANC performance were studied on the bases of both, simulations and
measurement. An improvement of the prototype could be achieved by
damping resonances. This reduces group delay in the path between the
speaker and the inner microphone, which is an important limiting factor
for ANC. The group delay of the inner microphone was found to be
significant for low frequencies. The investigations deliver valuable
knowledge about the influence of the different parameters of the
acoustic front-end on the important factors for ANC. An acoustic model
was obtained that allows the prediction of various transfer paths and an
easy fine tuning of the elements of the acoustic front-end.
All interested parties are cordially invited, registration is not required.
General information about the colloquium, as well as a current time
scale of the Communication Technology Colloquium can be found at:
https://www.iks.rwth-aachen.de/aktuelles/kolloquium
--
Irina Ronkartz
Institute of Communication Systems (IKS)
RWTH Aachen University
Muffeter Weg 3a, 52074 Aachen, Germany
+49 241 80 26958 (phone)
ronkartz(a)iks.rwth-aachen.de
http://www.iks.rwth-aachen.de/
Dear subscribers of the colloquium newsletter,
we are pleased to announce the next date of our Communication Technology
Colloquium:
*Thursday, June 17, 2021*
*Speaker*: Daniel Gotzens
*Time*: 11:00 a.m.
*Location*:
https://rwth.zoom.us/j/97904157921?pwd=SWpsbDl0MWhrWjY1ZkZaeFRoYmErZz09
Meeting-ID: 979 0415 7921
Passwort: 481650
*Bachelor Lecture*: Real-Time Own Voice Estimation for Hearables
Utilizing Multiple Microphone Signals
Hearable devices employ several microphones to be used in
telecommunication applications as well as for active noice cancellation.
It is proposed that the signals generated by these microphones can be
combined into an accurate and low-interference estimate of the user's
own voice in real time by using digital beamforming algorithms, namely
the so-called delay-and-sum and minimum variance distortionless response
beamformers, especially in conjunction with additional filtering in the
shape of a bandpass or a Wiener filter.
To test this, several input samples are recorded on a hearable device
and then processed with said algorithms. It is found that it is indeed
possible to generate such a signal using the proposed algorithms,
improving the signal to noise ratio by several decibels while
maintaining a low distortion of the speech signal.
All interested parties are cordially invited, registration is not required.
General information about the colloquium as well as a current time scale
of the Communication Technology Colloquium can be found at:
https://www.iks.rwth-aachen.de/aktuelles/kolloquium
--
Irina Ronkartz
Institute of Communication Systems (IKS)
RWTH Aachen University
Muffeter Weg 3a, 52074 Aachen, Germany
+49 241 80 26958 (phone)
ronkartz(a)iks.rwth-aachen.de
http://www.iks.rwth-aachen.de/