43results about "Pilot signal control" patented technology

An audio dynamics processor or processing method that uses a reset mechanism or process in order to adapt quickly to content changes in the audio signal. A reset signal may be generated by analyzing the audio signal itself or the reset may be triggered from an external event such as a channel change on a television set or an input selection change on an audio / visual receiver. In the case of an external trigger, one or more indicators of the state of the dynamics processor for a current audio source may be saved and associated with that audio source before switching to a new audio source. Then, if the system switches back to the first audio source, the dynamics processor may be reset to the state previously stored or an approximation thereof.

Methods and apparatus are provided for stabilizing the phase and gain of an amplifier in a power pooling arrangement. A pilot signal combining a reference carrier frequency with a reference sideband frequency is passed through the amplifier via an adjustable phase shifter and an adjustable attenuator in the amplifier input line. A portion of the amplified pilot signal is coupled from the output of the amplifier and mixed with the reference frequency. The remaining audio frequency signal is compared to a reference (input) audio signal to determine phase and gain changes during amplification in the amplifier. Phase and gain control signals are developed from this comparison, and are fed back to the adjustable phase shifter and adjustable attenuator, respectively, in order to compensate an incoming signal for phase and gain variations in the amplifier.

The invention relates to a transmitter (100) for multi-carrier communication. The transmitter (100) comprises a processor (101) for generating a training signal (S), wherein the training signal (S) comprises a first sub-signal (S1) and a second sub-signal (S2). The first sub-signal (S1) and the second sub-signal (S2) are sent continuously in time, and the frequency component of the first sub-signal (S1) is relative to the frequency of the second sub-signal (S2) The components are frequency shifted by a predefined amount. Said transmitter (100) also comprises a communication interface (103) for sending said training signal (S). The invention also relates to a receiver for performing channel distortion correction, in particular automatic gain control (AGC), based on said received training signal (S).

A method may include: receiving information indicative of an amplitude of an audio output signal; receiving information indicative of a predicted voltage of a power supply of a signal path having an audio input for receiving an audio input signal and for generating an audio signal based on the audio input signal audio output of the output signal; predicting whether the audio output signal will exceed an effective supply voltage generated by the power supply based on information representing the amplitude of the audio output signal and information representing a predicted voltage of the power supply; responsive to determining that the audio output signal will exceed the effective supply voltage generated by the power supply The effective supply voltage of the audio input signal or its derivative is attenuated to reduce the amplitude of the audio output signal so that the audio output signal does not exceed the effective supply voltage of the power supply.