Clean Audio for TV broadcast: An Object-Based Approach for Hearing-Impaired Viewers - April 2015
Audibility of a CD-Standard A/DA/A Loop Inserted into High-Resolution Audio Playback - September 2007
Sound Board: Food for Thought, Aesthetics in Orchestra Recording - April 2015
Virtual Microphones: Optimum Real-Time Demodulation of Phase Modulated Ultrasound
The project “Virtual Microphones” aims to replace conventional audio microphones by a system consisting of ultrasonic sensors. The fundamental physical principle utilized is that ultrasonic waves are phase-modulated when superimposed by audio waves. Due to the physical relationships the phase changes of the ultrasonic carrier are very small. The precise demodulation of the audio signal was in the focus of the investigation among other measures, like providing a very stable carrier frequency or the focusing of the ultrasound beam on the receivers. Several methods of demodulation for phase-modulated signals are compared. The comparatively low resulting signal-to-noise ratio after the demodulation required further signal processing in form of noise reduction to be investigated and its performance accessed.
Click to purchase paper or login as an AES member. If your company or school subscribes to the E-Library then switch to the institutional version. If you are not an AES member and would like to subscribe to the E-Library then Join the AES!
This paper costs $20 for non-members and is free for AES members and E-Library subscribers.
The Engineering Briefs at this Convention were selected on the basis of a submitted synopsis, ensuring that they are of interest to AES members, and are not overly commercial. These briefs have been reproduced from the authors' advance manuscripts, without editing, corrections, or consideration by the Review Board. The AES takes no responsibility for their contents. Paper copies are not available, but any member can freely access these briefs. Members are encouraged to provide comments that enhance their usefulness.