Abstract:
The present invention relates to a method of performing measurements by means of an audio system comprising passive loudspeakers, whereby said measurements are performed by using at least one of said loudspeakers for producing sound and at least one of said loudspeakers for measuring said sound. The present invention further relates to an audio system comprising N passive loudspeakers, wherein said audio system further comprises an output stage where each output acts as a combined output channel and a measurement input.
Abstract:
The invention relates to a hardware implemented filtering method comprising the steps of establishing a representation DIS of the derivative of at least a part of a timequantized input signal IS, and establishing at least one sample of a time- and amplitude-quantized output signal OS by performing filtering on the basis of at least a part of a filter representation IFC1, IFC2, IFC3 and said representation DIS of the derivative of at least a part of said input signal IS.The invention further relates to a hardware implemented decimation method for decimating a time-quantized input signal IS comprising the steps of - dividing said time-quantized input signal IS into intervals, for each of said intervals establishing a sample of a time- and amplitude-quantized output signal OS according to the above mentioned filtering method.The invention further relates to a fast filtering means FFM implementing the abovementioned methods.
Abstract:
The invention relates to an amplifier comprising amplification means (AM) comprising an input and an output, said amplification means (AM) comprising a switching output stage delivering at least one output signal (OUS) via said output, said amplification means being fed by power supply means (PSM) said amplifier further comprising compensation means (CM) providing a compensation signal (CS) derived from the power supply voltage (PSV) of the power supply means (PSM), said compensation signal (CS) comprising a substantially inverse representation of said power supply voltage (PSV) and said compensation signal (CS) being fed to said amplification means (AM). According to the invention, an effective error compensation of the output switching stage may in practice be implemented by establishment of a compensation, which on a run-time basis is based on the voltage of the power supply currently applied in the output switching stage.
Abstract:
The invention relates to a method of establishing a PWM-modulated output signal representation (OS), providing a stream of parallelly determined intersection representations (PIR) on the basis of a stream of parallel reference signal representation (PRSR) and an input signal (IS), establishing a serial PWM output signal representation (OS) by transforming said stream of parallelly determined intersection representations (PIR) into a stream of serial intersection representations (SIR) by means of a relative time shift of at least one of said parallelly determined intersections (PIR). According to an embodiment of the invention, an advantageous way of providing intersection estimates has been obtained, as each or at least a number of intersection estimates between a reference signal and an input signal may be established partially while taking only the individual partial reference functions into consideration.
Abstract:
The invention relates to pulse width modulator system (PWMS) comprising a modulator system input (MI), a modulator output (MO), an amplitude distribution filter (ADF), and a pulse width modulator (PMOD), wherein said amplitude distribution filter (ADF) establishes an intermediate output signal (OS) by modifying the level of the amplitude distribution of an input signal (IS) within at least one predetermined amplitude range of said input signal (IS), said input signal (IS) being received form said modulator system input (MI), and wherein said pulse width modulator (PMOD) provides a modulator output signal (MOS) on said modulator output (MO) on the basis of said intermediate output signal (OS).
Abstract:
The invention relates to at least one self-oscillating loop (SOL) comprising at least one forward path (FP), at least one feedback path (FBP) wherein said at least one forward path (FP) comprises amplitude quantizing means (AQM) combined with time quantizing means (TQM) and outputting at least one time and amplitude quantized signal (OS). According to the invention, a high-speed high-resolution A/D converter may be obtained.
Abstract:
The invention relates to a method of estimating an intersection between at least two continuous signal representations (SR1, SR2) in a pulse width modulator, at least one of said continuous signal representations (SR1, SR2) being non-linear, said method comprising the step of providing an intersection estimate (CPE) between said at least two continuous signal representations on the basis of at least one iteration comprising at least one iterative call of a function describing said continuous signal representations (SR1, SR2) being non-linear and whereby said estimating of intersections are performed in a pulse width modulation modulator. According to an embodiment of the invention, a simple iterative call of the established continuous signal representation, e.g. an interpolation polynomial, will provide the desired intersection. It should be noted that the established estimate might be provided without any complicated root solving and avoiding division and even square root.
Abstract:
The invention relates to a high-mode self-oscillating pulse modulator. According to the invention, a complete rethinking of preconditions for oscillation and modulation in an oscillating modulator as all conventional thinking of how to apply oscillation in a modulator has been set aside. Thus, according to the invention, high-mode oscillation refers to an oscillation at a higher mode than the first mode, which is conventionally regarded as the one and only applicable mode in an oscillating modulator.
Abstract:
The invention relates to an amplifier comprising amplification means (AM) comprising an input and an output, said amplification means (AM) comprising a switching output stage delivering at least one output signal (OUS) via said output, said amplifications means being fed by power supply means (PSM) said amplifier further comprising compensation means (CM) providing a compensation signal (CS) derived from the power supply voltage (PSV) of the power supply means (PSM), said compensation signal (CS) comprising a substantially inverse representation of said power supply voltage (PSV) and said compensation signal (CS) being fed to said amplification means (AM).
Abstract:
The invention relates to a self-oscillating circuit comprising comparator means (CM) comprising at least one input means (IM) and at least one output means (OM), at least one of said at least one output means (OM) is coupled to at least one of said at least one input means (IM) via at least one filtering means (FM), said at least one filtering means (FM) at least partly comprising demodulation means (DM), wherein said filtering means (FM) is of at least fifth order.