Monday, October 13 9:00 am 10:30 am
Session O Automotive Audio
O-1 Implementation of a Double StereoDipole System on a DSP BoardExperimental Validation and Subjective Evaluation Inside a Car CockpitChristian Varani, Enrico Armelloni, Angelo Farina, University of Parma, Parma, Italy
Sound reproduction in a car cockpit is a difficult task. Reverberation, reflection, noise, and vibration are some of the issues to consider. In this paper a more advanced technique (spatial equalization) is used, that also controls the phase of the signal and allows the virtual displacements of the sound source, improving stereo imaging and spatial envelopment. This technique may be implemented in real-time by FIR filters, whose coefficients are obtained by inversion of the measured impulse responses. The stereo-dipole is the system that employs this technique. In this work a pair of stereodipoles is used: one for the drivers seat and another one for the front passengers seat. The global system is validated by experimental listening and compare test.
O-2 Development of a Digital Amplifier for Car UseKenichi Taura, Masayuki Tsuji, Mitsubishi Electric Corporation, Kyoto, Japan; Tsuyoshi Nakada, Masayuki Ishida, Mitsubishi Electric Corporation, Hyogo, Japan
We have developed a digital amplifier for car use. The major problems of conventional digital amplifiers are lack of the ability to reject the ripple and noise on the car power line and the EMI (electro-magnetic interference). We have developed a novel feedback system for digital amplifiers to solve the supply voltage ripple problem. By using a prototype with a feedback system, we have confirmed that it gives enough supply voltage ripple rejection for car audio systems. We also confirmed that the feedback system contributes to reducing the EMI by relaxing the requirements of the switching stage operation, while keeping the audio output distortion low.
O-3 Software Radio Receiver for Audio and Video Broadcasting SystemsMaja Sliskovic, Hans-Jürgen Nitzpon, Harman/Becker Automotive Systems, Karlsbad, Germany
As new sound and video broadcasting systems are being deployed, the need for a multistandard multiband receiver increases. The compatibility of the software radio receiver with any defined broadcasting service is guaranteed by its reprogrammability, i.e., by the fact that its functionality is determined by software. In this paper a software implementation of the signal path from the ADC to the audio/video output will be discussed. The possibility of software reuse in different receiver functional blocks and for different broadcasting standards will be investigated.