Abstract: A contactless power transfer system is provided. The contactless power transfer system includes a first power exchanger coil configured to exchange power. The contactless power transfer system also includes a first power converter operatively coupled to the first power exchanger coil and configured to convert a direct current power to an alternating current power at a system frequency. The contactless power transfer system further includes a controller configured to control an operating state of the first power converter to vary an alternating current power provided to the first power exchanger coil at the system frequency.

Abstract: This disclosure provides systems, methods and apparatuses for wireless power transmission and reception. A wireless power transmission apparatus may include a primary coil that transmits power to a corresponding secondary coil in a wireless power reception apparatus. The wireless power transmission apparatus may configure characteristics of the wireless power transmission based on a load setting of a wireless power reception apparatus. The wireless power transmission apparatus may take into account a coupling factor and power transfer characteristics of the wireless power reception apparatus in determining a configuration of the wireless power transmission from the wireless power transmission apparatus to the wireless power reception apparatus. In some implementations, a change in wireless power transmission may occur based on a corresponding change in the load. For example, the change in wireless power transmission and the corresponding change in the load may occur in relation to a synchronization event.

Abstract: This disclosure provides systems, devices, apparatus and methods, including computer programs encoded on storage media, for wireless power transmission. A wireless power transmission apparatus (such as a charging pad) may provide multiple wireless power signals to a wireless power receiving apparatus. The wireless power receiving apparatus may combine wireless power received from multiple secondary coils to provide a combined wireless power signal to a load, such as a battery charger or electronic device. In some implementations, each set of primary coil and secondary coil may utilize low power wireless power signals (such as 15 Watts or less) in accordance with a wireless charging standard. By combining wireless energy from multiple low power wireless power signals, the wireless power receiving apparatus may support higher power requirements of an electronic device. The disclosed designs may minimize electromagnetic interference (EMI) and provide greater efficiency of wireless power transfer.

Abstract: This disclosure provides systems, methods and apparatuses for a new communication technique between a wireless power transmission apparatus and a wireless power reception apparatus. The new communication technique may be more efficient for communication of a feedback parameter or other control information compared to a legacy packet-based digital communication technique. The new communication technique may use a pulse width modulation (PWM) signal as an analog representation of a feedback parameter or other control information. In some implementations, the PWM communication technique in this disclosure can be used for a variety of control or feedback information from the wireless power reception apparatus to the wireless power transmission apparatus. Furthermore, in some implementations, the PWM communication technique may be used for feedforward information from the wireless power transmission apparatus to the wireless power reception apparatus.

Abstract: Disclosed are examples of systems, apparatus, methods and computer-readable storage media for dynamically adjusting thresholds of a compressor. An input audio signal having a number of frequency band components is processed. Time-varying thresholds can be determined. A compressor performs, on each frequency band component, a compression operation having a corresponding time-varying threshold to produce gains. Each gain is applied to a delayed corresponding frequency band component to produce processed band components, which are summed to produce an output signal. In some implementations, a time-varying estimate of a perceived spectrum of the output signal and a time-varying estimate of a distortion spectrum induced by the perceived spectrum estimate are determined, for example, using a distortion audibility model. An audibility measure of the distortion spectrum estimate in the presence of the perceived spectrum estimate can be predicted and used to adjust the time-varying thresholds.

Abstract: Noise discrimination in signals from a plurality of sensors is conducted by enhancing the phase difference in the signals such that off-axis pick-up is suppressed while on-axis pick-up is enhanced. Alternatively, attenuation/expansion are applied to the signals in a phase difference dependent manner, consistent with suppression of off-axis pick-up and on-axis enhancement. Nulls between sensitivity lobes are widened, effectively narrowing the sensitivity lobes and improving directionality and noise discrimination.

Abstract: A method, system, and computer programs for improving the image quality of one or more predicted frames in a video image compression system, where each frame comprises a plurality of pixels. A picture region or macroblock of certain types of frames can be encoded by reference to one or more referenceable frames in some cases, and by reference to two or more referenceable frames in other cases. Such encoding may include interpolation, such as an unequal weighting. The DC value or AC pixel values of a picture region may be interpolated as well, with or without weighting. A code pattern of such frames having a variable number of bidirectional predicted frames can be dynamically determined. Frames can be transmitted from an encoder to a decoder in a delivery order different from a display order. Sharpening and/or softening filters can be applied to a picture region of certain frames during motion vector compensated prediction.

Abstract: A method, system, and computer programs for improving the image quality of one or more predicted frames in a video image compression system, where each frame comprises a plurality of pixels. A picture region or macroblock of certain types of frames can be encoded by reference to one or more referenceable frames in some cases, and by reference to two or more referenceable frames in other cases. Such encoding may include interpolation, such as an unequal weighting. The DC value or AC pixel values of a picture region may be interpolated as well, with or without weighting. A code pattern of such frames having a variable number of bidirectional predicted frames can be dynamically determined. Frames can be transmitted from an encoder to a decoder in a delivery order different from a display order. Sharpening and/or softening filters can be applied to a picture region of certain frames during motion vector compensated prediction.

Abstract: A method, system, and computer program for coding video frames in a video compression system. One aspect includes automatically scaling coding mode biases as a function of the number of bits of coding precision in the video compression system, or dynamic range and/or contrast range, or quantization parameter. Another aspect includes selecting coding mode biases as a function of the total number of bits required for macroblock coding, or setting all biases to zero. Another aspect includes selecting one of a plurality of coding modes (1) resulting in no more than a selected number of coded bits, or (2) having at least a selected image quality, or (3) having a combination of number of coded bits and image quality. Another aspect includes selecting, as a preferred coding mode, one of a plurality of coding modes having a selected combination of number of coded bits and image quality based on various AC and DC motion vectors.

Abstract: Noise reduction of a signal such as a video signal is effected by averaging a plurality of relatively delayed replica signals, e.g. with line or field delays therebetween, in a decoding processor, the highly redundant information content of the signal being reinforced by the averaging while random noise undergoes a partial cancellation. In order to overcome the problem of signal changes caused by the decoding processor, the signal is encoded prior to application to the noise-introducing signal channel by a complementary encoding processor in which one or more replica signals are subtractively combined with one or more other replica signals. In both processors a variable combining means is employed to exclude from the combination replica signals which have a non-small difference from the replica signals in the combination, thereby to avoid smearing of the information content (with consequent picture smearing in the case of a video signal) when the signal is changing, e.g. because of movement in a picture.

Abstract: A variable area sound track is scanned laterally to derive width-modulated pulses which can be demodulated to audio. In order to eliminate the effect of noise on the clear area of the track, each pulse is initiated by a black-to-clear transition sensed in the scanning but is not terminated until it is certain that the clear-to-black transition has been reached, e.g. at reference instants of time.

Abstract: A variable area sound track is scanned laterally to derive width-modulated pulses which can be demodulated to audio. In order to eliminate the effect of noise on the clear area of the track, each pulse is initiated by a black-to-clear transition sensed in the scanning but is not terminated until it is certain that the clear-to-black transition has been reached, e.g. at reference instants of time.

Abstract: A network is described which processes two channel stereophonic sound programs for playback through left, right and center sound reproduction channels. Use of the network allows certain advantages of a three channel program to be obtained from the two channel program. The network delays the left and right channels to give precedence to the center channel information but reduces the level of this information to enable the left and right channels to establish a stereo image.

Abstract: In a known variable impedance circuit with the variable impedance established across junctions of transistors connected in two branches between a control current source, for variably forward-biasing the junctions, and an equalizing circuit for equalizing the currents in the branches, the balance of the circuit is upset when an amplifier connected to one branch draws input bias current therefrom. This problem is overcome by a transistor connected to the other branch to draw a matching current from the second branch. Transistors may be connected to both branches to increase the currents in the equalizing circuit and thereby improve the operation thereof when the control current is reduced to a low value for obtaining a high impedance.

Abstract: In a stereophonic reproduction system, especially for a cinema, a center channel signal is derived by combining left and right channel signals. In order to harden the center image, particularly in speech, the left and right channel signals are compared and, when they include significant amounts of correlated information, the relative gain of the center channel is enhanced by boosting the gain of that channel and/or cutting the gain of the left and right channels. The test for correlation of information is preferably restricted to speech frequencies and the enhancement of relative gain may be performed only at middle frequencies.

Abstract: In a signal compressor wherein an amplified and smoothed control signal is employed to control a variable gain or variable impedance device, a switch is provided to connect a positive feedback loop across the control signal amplifier, thereby to place the compressor in an oscillator mode for providing an alignment or calibration signal of stable amplitude.

Abstract: In a floating electrical output circuit according to co-pending application Ser. No. 395,608, now U.S. Pat. No. 3,909,737, issued Sept. 30, 1975, two load terminals are driven from amplifying means having differential current outputs. A differential amplifier connected across the load terminals provides a feedback signal which is compared with the input signal to provide a control signal for the amplifying means.In the present invention the amplifying means are simplified to a single differential current amplifier.

Abstract: The invention concerns a dynamic range compressor type encoder or expander type decoder, in which a main signal component in a main path is boosted or bucked by a further signal component derived from a point in the main path by a further path having the characteristics of so restricting the further signal component that the boosting or bucking action is only appreciable below a low level threshold. In the present invention the further signal component is a difference signal formed between a direct signal derived from a point in the main path and a delayed version of either the same signal or of another signal derived from another point in the main path. At the frequency equal to the reciprocal of the delay, and at harmonics of this frequency, the direct and delayed signals cancel. The compressor or expander action, and hence noise reduction action, takes place only at intervening frequencies.

Abstract: A compressor or expander circuit is constructed by connecting a plurality of impedance networks in series across input terminals, at least one network being frequency selective. Output terminals are connected across one or more of the networks. The frequency selective network varies its parameters in response to the level of components within a restricted frequency band determined by this network so as to narrow the band when the level of such components increases. This includes such components from the restricted band and thereby from the compression or expansion action.

Abstract: The invention concerns a dynamic range compressor type encoder or expander type decoder, in which a main signal component in a main path is boosted or bucked by a further signal component derived from a point in the main path by a further path having the characteristics of so restricting the further signal component that the boosting or bucking action is only appreciable below a low level threshold. In the present invention the further signal component is a difference signal formed between a direct signal derived from a point in the main path and a delayed version of either the same signal or of another signal derived from another point in the main path. At the frequency equal to the reciprocal of the delay, and at harmonics of this frequency, the direct and delayed signals cancel. The compressor or expander action, and hence noise reduction action, takes place only at intervening frequencies.