Scientific Papers about NU-Tech

Find listed here all the scientific papers dealing with NU-Tech.

Let us know if you have used NU-Tech in your research to show your scientific results, for example.

Development of Multipoint Mixed-Phase Equalization System for Multiple Environments
Conference: AES 134th Convention, May 2013 - Rome, Italy
Abstract: The development of a mixed-phase equalizer is still an open problem in the field of room response equalization. In this context, a multipoint mixed-phased impulse response equalization system is presented taking into consideration a magnitude equalization procedure based on a time-frequency segmentation of the impulse responses and a phase equalization technique based on the group delay analysis. Furthermore, an automatic software tool for the measurement of the environment impulse responses and for the design of a suitable equalizer is presented. Taking advantage of this tool, several tests have been performed considering objective and subjective analysis applied in a real environment and comparing the obtained results with different approaches.

Investigation into electric vehicles exterior noise generation
Conference: AES 133rd Convention, October 2012 - San Francisco, USA
Abstract: Electric vehicles have been receiving increasing interest in the last years for the well-known benefit that can be derived. However, electric cars do not produce noise as does an internal combustion engine vehicle, thus leading to safety issues for pedestrians and cyclists. Therefore, it is necessary to create an external warning sound for electric cars maintaining users sound quality expectation. In this context several sounds generated with different techniques are here proposed, taking into consideration some aspects of real engine characteristics. Furthermore, a subjective investigation is performed in order to define users preferences in the wide range of possible synthetic sounds.

Multipoint Equalization for Car Audio Systems
Conference: AES 48th Conference on Automotive Audio, September 2012 - Munich, Germany
Abstract: In this paper a novel approach for automotive sound system enhancement based on multipoint equalization is presented. Beginning from well known techniques applied to room equalization issues, a frequency domain algorithm that combines fractional octave smoothing of measured impulse responses (IRs) in multiple locations is developed. The IRs are calculated using well positioned microphones inside a car taking into account the properties of the environment. Several results are presented considering different methods to combine the IRs and confirming the validity of the approach in comparison with single point equalization.

Optimized implementation of an innovative digital audio equalizer
Conference: AES 133rd Convention, October 2012 - San Francisco, USA
Abstract: Digital audio equalization is one of the most common operations in the acoustic field, but its performance depends on computational complexity and filter design techniques. Starting from a previous FIR implementation based on multirate systems and filterbanks theory, an optimized digital audio equalizer is derived. The proposed approach employs all-pass IIR filters to improve the filterbanks structure developed to avoid ripple between adjacent bands. The effectiveness of the optimized implementation is shown comparing it with the FIR approach. The solution presented here has several advantages increasing the equalization performance in terms of low computational complexity, low delay, and uniform frequency response.

Real-Time Implementation of Wave Field Synthesis on NU-Tech Framework Using CUDA Technology
Conference: 128th AES Convention, May 2010 - London, UK
Abstract: In this paper we present a novel implementation of a Wave Field Synthesis application based on emerging NVIDIA Compute Unified Device Architecture (CUDA) technology using NU-Tech Framework. CUDA technology unlocks the processing power of the Graphics Processing Units (GPUs) that are characterized by a highly parallel architecture. A wide range of complex algorithms are being re-written in order to benefit from this new approach. Wave Filed Synthesis is a quite new spatial audio rendering technique highly demanding in terms of computational power. We present here results and comparisons between a NU-Tech Plug-In (NUTS) implementing real-time WFS using CUDA libraries and the same algorithm implemented using Intel Integrated Primitives (IPP) Library.

The hArtesCarlab: hardware implementation and algorithm development
Conference: 36th AES International Conference - Sound in Motion, June 2-4, 2009 Dearborn, Michigan, USA
Abstract: In the last decade Car Infotainment Systems (CIS) have been gaining great attention by the scientific and industrial community: in this context, within the Euro- pean hArtes Project, an advanced CIS (ACIS) has been designed. The system offers several functionali- ties employing professional audio equipment and PCs able to manage different I/O audio channels and to provide a large computing capability for complex audio algorithms. The overall architecture is based on NU-Tech platform that manages the whole system from professional equipment to audio streaming and processing. The system has been therefore devised as a real audio laboratory (hArtes CarLab) for audio algorithm exploration and validation, providing a remote access to all the system functionalities. In this paper starting from the hardware description, a com- plete set of algorithms to enhance audio reproduction, hands-free communication, and interactivity through speaker and speech recognition features is discussed in relation to the NU-Tech framework.

Implementing a Car Infotainment System using NU-Tech Framework
Conference: 2009 IEEE International Conference on Networking, Sensing and Control - Okayama City, Japan, March 26-29, 2009
Abstract: NU-Tech framework is a powerful Digital Signal Processing tool for algorithms developing. Its main advantage is to give the user a set of high level functions which make easier and faster the development of an application from scratch. As an example an advanced Car Infotainment System platform, composed by several physical systems and able to manage different computational demanding applications, based on a Client-Server architecture is here presented.

Demonstrating hArtes project approach through an Advanced Car Information System
Conference: The First Annual International Symposium on Vehicular Computing Systems - 22nd - 24th July 2008 - Dublin, Ireland
Abstract: The need for an Advanced Car Information System has been recently emerging, able to handle issues left open by CIS systems already on the market, and to overcome their limitations. In the hArtes framework an innovative approach is proposed, based on a general purpose Operating System with support for human interface and advanced Remote Application Control (RAC) following a client-server paradigm, and (sub)systems implementing specific demanding functions. In this context, an auxiliary system, whose interfacing software is derived from Nu-Tech DSP platform, is able to run computational-demanding applications using specialized hardware and software, offering remote control through the RAC model. The proposed architecture shows several advantages, such as increased flexibility, ease of integration with personal devices, software and hardware (individually replaceable modules) upgradability.

NU-Tech: the entry tool of the hArtes toolchain for algorithms design
Conference: 124th AES Convention 2008 May 17-20 Amsterdam, The Netherlands
Abstract: The aim of the hArtes project is to facilitate and automate the rapid design and development of heteroge- neous embedded systems, targeting a combination of a general purpose embedded processor, digital signal processing and reconfigurable hardware. In this paper, we present the NU-Tech platform, the main entry tool from the hArtes toolchain, which has the role of assisting the designers in tuning and possibly improve the input algorithm at the highest level of abstraction. A brief description of the project itself will be given and its vocation to audio highlighted through a case study application.

Sub-band adaptive crosstalk cancellation: a novel approach for immersive audio
Conference: 124th AES Convention 2008 May 17-20 Amsterdam, The Netherlands
Abstract: In the field of immersive audio, crosstalk canceller is required when a virtual sound is rendered over two loudspeakers. In the last decade several adaptive algorithms have been proposed: nowadays the least square (LMS) algorithm seems to be the best compromise between simplicity and robustness although its convergence is weak for colored inputs. In this work a new approach to crosstalk cancellation based on a sub-band adaptive algorithm will be derived. The effectiveness of this algorithm, considering colored input, will be presented in terms of matrix inversion quality and fast convergence rate comparing it with the conventional LMS algorithm.

Real time implementation of an innovative digital audio equalizer
Conference: 123th AES Convention, New York, NY, USA, 2007 October 5-8
Abstract: Fixed frequency response audio equalization has well-known problems due to algorithms computational complexity and to the filters design techniques. This paper describes the design and the real time implementation of a M-band linear phase digital audio equalizer. Beginning from multirate systems and filter banks, an innovative uniform and non uniform bands audio equalizer is derived. The idea of this work arises from different approaches employed in filter banks to avoid aliasing in the case of adaptive filtering in each band. The effectiveness of the real time implementation is shown comparing it with an equalizer based on frequency domain technique. The solution presented here has several advantages in terms of low computational complexity, low delay and uniform frequency response avoiding ripple between adjacent bands.

Linear Phase Mixed FIR/IIR Crossover Networks: Design and Real-Time Implementation
Conference: 123th AES Convention, New York, NY, USA, 2007 October 5-8
Abstract: Crossover networks are crucial components of audio reproduction systems and therefore they have received great attention in literature. In this paper, the design and implementation of a digital crossover will be presented. A mixed FIR/IIR solution has been explored in order to exploit the respective strengths of FIR and IIR realizations, aiming at designing a low delay, low complexity, easily extendible, approximately linear phase crossover network. A software real-time implementation for the Nu-Tech platform of the proposed system will be shown. Practical tests have been carried out to evaluate the performance of the proposed approach.

NU-Tech: implementing DSP Algorithms in a plug-in based software platform for Real Time Audio applications
Conference: 118th AES Convention, Barcelona, Spain, 2005 May 28-31
Abstract: This work presents a novel software platform called NU-Tech to implement real-time DSP algorithms in multi-channel scenarios. Running on a common PC, the overall framework is based on a plug-in architecture, allowing the user to connect specific blocks, operating as DSP algorithms, within the available graphical design environment. These blocks, namely NUTs’ (NU-Tech Satellites), have to be previously written in C++. A strict control over latency times is insured by a proper interface to the hardware layer of the PC sound card. It turns out that NU-Tech is well suited for development, real-time debugging and fine tuning of DSP algorithms. As further application, it fulfils the role of DSP operating core of new stand-alone programs preventing the user to develop them from scratch. Some examples are provided to show the effectiveness of the idea.

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