Abstract:
An electronic device has two oscillators, for example a first highly accurate crystal oscillator and a second less accurate low power oscillator. In a normal mode of operation, time is counted based on an output from the crystal oscillator, but in a low power mode of operation, time is counted based on an output from the less accurate oscillator. During the low power mode of operation, a calibration process is performed repeatedly. During a first calibration time period the second oscillator is calibrated against the first oscillator to obtain a first calibration result, and a recalibration is performed during a second calibration time period to obtain a second calibration result. A correction factor is determined from the first and second calibration results, and the correction factor is applied when subsequently counting time based on the output from the second oscillator.
Abstract:
One aspect of the invention is a homodyne coherent receiver, suitable for high speed phase shift keying (PSK), the receiver comprising a receiver for receiving an incoming signal having a carrier-less modulation format, a signal conditioning sub-system that generates a carrier component from the incoming signal, and an optical injection phase locked loop (OIPLL) that phase locks the generated carrier component of the incoming signal. Embodiments of the invention may enable DSP free detection of optical PSK signals, which may be required in next generation fiber transmission systems and in optical constellation analyzer systems. In addition, embodiments of the invention may provide improved receiver sensitivity performance comparing to prior art systems using direct detection schemes. Also, embodiments of the invention may be advantageous in terms of cost and energy efficiency.
Abstract:
A post-distortion method for cascading amplifier stages in a two-stage microwave power amplifier and a dynamic biasing method using back-end processing for correcting nonlinearity in the power amplifier output. A first or driver stage biased in a near-A region with low distortion is cascaded with a second or power stage biased in a near-C region with high efficiency. The amplitude and phase responses of the two stages compensate another to yield a more linear overall gain for the overall power amplifier. The dynamic biasing scheme modulates the source to drain voltages of the transistors used in the amplifier stages based on the harmonics in amplifier output in order to minimize the harmonics and correct non-linearity in the output.
Abstract:
An optical transmitter is of the reflective modulation type and has a means of generating reflection, a mixer for mixing a data stream and a sub-carrier, and an optical modulator for modulating an optical carrier with the output from the mixer in order to avoid optical beat-interference noise arising from, for example, Rayleigh backscattering. The modulator is in one embodiment of the interferometric type such as a Mach-Zehnder Modulator (MZM) operated to suppress the optical carrier at the transmitter output in order to reduce optical beat interference noise. The modulator preferably implements CSS-AMPSK modulation, which suppresses optical beat noise and achieves strong dispersion tolerance, enabling, for example, 10 Gb/s data transmission over 100 km distance without dispersion compensation. The transmitter may have a duobinary encoder, which encodes the data prior to mixing with the sub-carrier.
Abstract:
A computing device comprising a plurality of devices and a plurality of visual indicators is disclosed. Each of the plurality of visual indicators is interconnected with a power source and is associated with a different one of the plurality of devices. None of the plurality of visual indicators comprises a capacitor.
Abstract:
A post-distortion method for cascading amplifier stages in a two-stage microwave power amplifier and a dynamic biasing method using back-end processing for correcting nonlinearity in the power amplifier output. A first or driver stage biased in a near-A region with low distortion is cascaded with a second or power stage biased in a near-C region with high efficiency. The amplitude and phase responses of the two stages compensate another to yield a more linear overall gain for the overall power amplifier. The dynamic biasing scheme modulates the source to drain voltages of the transistors used in the amplifier stages based on the harmonics in amplifier output in order to minimize the harmonics and correct non-linearity in the output.
Abstract:
A method to store, retrieve, and search information is disclosed. The method encodes information comprising a plurality of datasets in a holographic data storage medium to form an encoded holographic data storage medium, and encodes that same information to one or more of a plurality of non-holographic data storage media. The method then selects a dataset comprising a portion of the information, where that dataset is written to a dataset storage address on the non-holographic data storage medium, and illuminates the encoded holographic data storage medium with a dataset beam comprising that dataset to produce a dataset reference beam, such that the dataset reference beam strikes the optical detector at one or more dataset reference beam coordinates. The method then associates the dataset with the one or more dataset reference beam coordinates and with the dataset storage address.
Abstract:
A compact amplifier output bias circuit is used as a broadband harmonic termination. The bias circuit is adapted as a harmonic termination circuit to produce an effective low impedance or act as a load at the signal harmonic frequencies while having the capability of supplying DC power to the amplifier stage, optionally, if needed. A pi network is coupled to an active device output and provides a low impedance at frequency bands above a frequency band of operation while allowing DC bias to be appliable to the active device output.
Abstract:
An exercise device having a bar with a first handle, a grip exerciser having a second handle connected to the bar via a resistance member proximate the first handle and moveable between a first position and a second position by a hand of a user; and an auxiliary device connected to the bar selected from a light assembly, a sound generator, an electrified defensive unit, a pressurized defensive unit, and combinations of the same.