Decorrelation in Adaptive Feedback Cancellation for Public Address Systems

Public Address systems that include a setup with at least one microphone and speaker can suffer from acoustic feedback. This results in an annoying howling effect which can damage hardware and human hearing. To solve this issue, an adaptive filter that estimates the feedback path and uses this estimate to cancel the feedback can be designed....

Adaptive filtering in adaptive feedback cancellation for PA systems

This report is written as part of the Bachelor Graduation Project in the third year of the Electrical Engineering Bachelor programme at the Delft University of Technology. This report is made by a subgroup that is part of a larger project dedicated to finding a solution to frequency feedback in electroacoustic systems, also known as the Larsen...

Postfiltering in Adaptive Feedback Cancellation for PA Systems

The most promising method for acoustic feedback control in public address systems is adaptive feedback cancellation (AFC). This approach is based on making an estimation of the room impulse response, which is used to subtract an estimate of the feedback from the microphone signal. A postfilter is often used to improve the performance of such an...

On Determining Smartphone Microphone Directivity with Application to Beamforming

An equiangular sampling scheme and accessory measurement set-up for determining the directivity gain pattern of a commercially available smartphone is presented. Determining this directivity gain pattern based on these measuremenents was not possible, because next to the impulse response of the microphone also the impulse response of the...

Indoor Localization using Signals of Opportunity

This thesis proposes an algorithm to solve the issue of indoor localization using a source, reference receiver and mobile receiver placed in a convex room. The goal is determination of the position of the mobile receiver. The proposed algorithm consists of two localization techniques known from scientific literature: Time Difference of Arrival...