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EETE NOV 2014

The sounds of silence in the car By Christoph Hammerschmidt Infotainment system vendor Harman has succeeded in applying noise cancellation technology, hitherto known mostly from headphones to the interior of cars: the company’s Road Noise Cancellation (RNC) noise management solution, jointly developed with British sports cars legend Lotus Engineering, minimises noise generated by the contact of the tires with the road surface. RNC, currently on its way to market introduction, will not only ensure a more comfortable while more quiet driving experience. The technology also has a strong economic aspect: It enables carmakers to use lighter weight materials and improve fuel economy without compromising vehicle noise levels. In pursuing ways to lessen the environmental impact of vehicles and raise fuel efficiency, car designers are reducing vehicle weight, often by using less noisedampening insulation in the car’s interior. The use of lighter materials, however, increases perceptible road noise inside the vehicle, which then penetrates the interior (and passenger ears) and also compromises the audio experience of the on-board infotainment system. Traditional NVH (Noise, Vibration, and Harshness) methods have difficulties mitigating these issues satisfactorily, and these technologies also tend to add weight, which cancels out the fuel economy effect of using lighter materials. With the latest Harman solution, drivers and passengers can soon look forward to a quieter ride. The Harman HALOsonic noise management suite comprises a Road Noise Cancellation solution (RNC) which detects and neutralizes unwanted road noise, and thereby creates opportunities to improve vehicle weight and handling without impacting interior noise levels. Being the first solution of its kind in the industry, RNC is based on the principle of using “anti-noise” to counteract road noise. To implement RNC, the chassis of the vehicle is fitted with accelerometers which enable the system to measure correlation of vibration coming from the road and the resulting noise inside the cabin. Subsequently, Harman’s algorithm in the controller creates inverse sound waves through the car’s audio system loudspeakers to cancel out the noise caused by the roadinduced vibration. It is also able to cope with the broadband nature of road noise, with its wide range of frequencies. The solution at hand can reduce the peaks of the noise across the target frequency range, creating a quieter experience within the vehicle cabin. HALOsonic consists of a suite of noise management technologies to improve noise levels and to enhance and contour sound inside and outside the vehicle. In addition to RNC, HALOsonic comprises Engine Order Cancelation (EOC) and internal as well as external Electronic Sound Synthesis. External ESS (eESS) generates sound primarily for hybrids and electric vehicles, creating the authentic sounds which drivers and pedestrians are familiar with from combustion engines, thereby increasing safety both for drivers and other road users. Internal ESS (iESS) serves to generate unique sound signatures for vehicles to contour and accentuate the engine sound. PUBLISHER André Rousselot +32 27400053 andre.rousselot@eetimes.be Editor-in-Chief Julien Happich +33 169819476 julien.happich@eetimes.be EDITORS Christoph Hammerschmidt +49 8944450209 chammerschmidt@gmx.net Peter Clarke +44 776 786 55 93 peter.clarke@eetimes.be Paul Buckley +44 1962866460 paul@activewords.co.uk Jean-Pierre Joosting +44 7800548133 jean-pierre.joosting@eetimes.be Circulation & Finance Luc Desimpel luc.desimpel@eetimes.be Advertising Production & Reprints Lydia Gijsegom lydia.gijsegom@eetimes.be Art Manager Jean-Paul Speliers Accounting Ricardo Pinto Ferreira Regional Advertising Representatives Contact information at: http://www.electronics-eetimes.com/en/ about/sales-contacts.html ELECTRONIC ENGINEERING TIMES EUROPE is published 11 times in 2014 by European Busines Pres SA 7 Avenue Reine Astrid, 1310 La Hulpe, Belgium Tel: +32-2-740 00 50 Fax: +32-2-740 00 59 email: info@eetimes.be. www.electronics-eetimes.com VAT Registration: BE 461.357.437. Company Number: 0461357437 RPM: Nivelles. Volume 16, Issue 10 EE Times P 304128 It is is free to qualified engineers and managers involved in engineering decisions – see: http://www.electronics-eetimes.com/subscribe © 2014 E.B.P. SA All rights reserved. P 304128 european business press 50 Electronic Engineering Times Europe November 2014 www.electronics-eetimes.com


EETE NOV 2014
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