Abstract:
A method for transforming an audio signal and a system employing that method is disclosed. The method proceeds by extracting from the signal components that fall within a stop band, for example, using one or more low-pass filters. Then, a set of one or more harmonics of the extracted components is generated by down-sampling to create an intermediate signal, which is then repeated. Each harmonic is then weighted by controlling its gain by application to it of a respective weighting factor, the factors being determined by the psychoacoustic properties of a system that will reproduce the signal. Then, the weighted harmonics are added to the audio signal (which may have been subject to a delay to ensure synchronisation) to create an output signal.
Abstract:
A method for estimating one or more parameters of a ultra wideband signal and a receiver system for receiving ultra wideband signals is provided. The method for estimating one or more parameters of a signal in an ultra wide band system including estimating the parameter(s) for a first signal element in a received signal then removing this signal element from the signal to obtain a modified signal. The parameter(s) for a number of further signal elements are then estimated and these elements are removed from the modified signal to form a refined signal. The parameter(s) for the first signal element are re-estimated to re-define the first signal element based on the refined signal minus the signal element having the greatest amplitude. The parameter(s) for the signal element having the greatest amplitude are re-estimated to re-define this signal element. The steps are repeated to generate a refined estimate of the parameter(s) for the first signal element. There is also disclosed a receiver for performing the above steps.
Abstract:
A dynamic assignment of the spreading codes of a user in a CDMA system is based on multipath channel conditions of that user. The spreading codes are assigned such that multipath signal energies are coherently integrated at the antenna of the receiver to ensure that the multipath components are summed constructively and therefore that a signal gain is obtained. The method is applicable to any CDMA system which uses spreading codes over a multipath channel. A specific algorithm for selecting the codes based on channel parameters and auto-correlation functions of the spreading codes is proposed.
Abstract:
A method for transforming an audio signal and a system employing that method is disclosed. The method proceeds by extracting from the signal components that fall within a stop band, for example, using one or more low-pass filters. Then, a set of one or more harmonics of the extracted components is generated by down-sampling to create an intermediate signal, which is then repeated. Each harmonic is then weighted by controlling its gain by application to it of a respective weighting factor, the factors being determined by the psychoacoustic properties of a system that will reproduce the signal. Then, the weighted harmonics are added to the audio signal (which may have been subject to a delay to ensure synchronization) to create an output signal.
Abstract:
A method and apparatus are proposed for automatically recognizing observed audio data. An observation vector is created of audio features extracted from the observed audio data and the observed audio data is recognized from the observation vector. The audio features include features are selected from a group of 3 types of features obtained from the observed audio data: (i) ICA features obtained by processing the observed audio data, (ii) first MFCC features obtained by removing a logarithm step from the conventional MFCC process, or (iii) second MFCC features obtained by applying the ICA process to results of a mel scale filter bank.
Abstract:
The present invention proposes a system in which an ultrasonic carrier beam is modulated using an audio input signal. The audio signal is divided into frequency bands, and that frequencies in different ones of these bands are treated differently. Specifically, different modulating schemes are used for different frequency bands. Also, different transducer aperture sizes are used for different frequency signals. Also, a further frequency equalizer is provided within each of the frequency bands. Finally, a relatively smaller amplitude modulating index (or indices) is used for signals in low frequency band(s).
Abstract:
A transducer array comprises a conductive back plate 32, a conductive front plate 33 having openings 62, and a plurality of piezoelectric vibrator elements 31 located in an array between the plates. The vibrator elements 31 are two-layer elements which each include a metal portion 311 and a PZT element 312. These elements 311, 312 are in electrical contact with the respective plates. The vibrator elements 31 are attached to support elements 51 upstanding as part of the back plate 32. The transducer array can be formed as a batch process in which the vibrator elements 31 are formed simultaneously, and then simultaneously attached to the support elements 51.
Abstract:
The present invention proposes a system in which an ultrasonic carrier beam is modulated using an audio input signal. The audio signal is divided into frequency bands, and that frequencies in different ones of these bands are treated differently. Specifically, different modulating schemes are used for different frequency bands. Also, different transducer aperture sizes are used for different frequency signals. Also, a further frequency equalizer is provided within each of the frequency bands. Finally, a relatively smaller amplitude modulating index (or indices) is used for signals in low frequency band(s).
Abstract:
A local positioning system is proposed for wirelessly locating an object using existing features within a static environment, such as walls, as the references for determining the position of the system. An antenna 16 attached to the object transmits RF signals which are reflected by the surroundings. During a training mode, the reflected signals are used to train a neural network 22, 43 to map the position of the object to the characteristics of the reflected signals. During a working mode, the trained neural network is to identify the position of the object based on reflected signals in working mode. Optionally, the reflected signals may be subject to a clustering process before input to the neural network.
Abstract:
An antenna including one or more IC bond bands configured to connect to a signal port on an IC, one or more substrate bond pads, a bond wire antenna (BWA) connected between the one or more IC bond bands and the substrate bond pads, and a resonant cavity adjacent the one or more substrate bond pads.