Active Noise Control in Aircraft Algorithms and Applications

Abstract: The thesis consists of five papers which are divided into three main parts. Parts A and B deal with active noise control in a propeller aircraft application, whereas Part C deals with active noise control in a helicopter application. Part A presents a comparison between single- and multiple-reference controllers, while Part B deals with different multiple-reference, multiple-channel algorithms. Finally, Part C presents a hybrid headset. The five papers comprise: Part A1: Comparison between a Single-- versus a Twin--Reference Controller in Narrowband ANC Applications. Part A2: Performance of a Multiple- versus a Single-Reference MIMO ANC Algorithm based on a Dornier 328 Test Data Set. Part B1: A Novel Multiple--Reference, Multiple--Channel, Normalized Filtered--X LMS Algorithm for Active Control of Propeller-Induced Noise in Aircraft Cabins. Part B2: Evaluation of Multiple--Reference Active Noise Control Algorithms on Dornier 328 Aircraft Data. Part C: A New Active Headset for a Helicopter Application. The test data sets used in the computer evaluations are based on real--life data throughout. The data was recorded in a twin-engine propeller aircraft (Dornier 328) and a Super Puma helicopter during flight.