Abstract: A signal processing methodology and circuit for supplying bias power and duty cycle information across an isolation barrier, wherein, at an input side of the isolation barrier at least one input signal carrying input duty cycle information, together with DC bias power, is received and encoded on a constant repetition rate, constant duty cycle carrier waveform. Encoding is carried out by an encoder implemented to encode the carrier waveform with a marker, such as a waveform discontinuity, at a timing corresponding to the input duty cycle information, and wherein the presence of the marker leaves the average value of the carrier waveform unaffected. At the output side of the isolation barrier, the duty cycle information may be received by a decoder, the input duty cycle information detected to reconstruct the at least one input signal, and optionally DC bias power extracted from the carrier waveform.

Abstract: Magnetic Vector Steering (MVS) and Half-Cycle Amplitude Modulation (HCAM) are novel techniques which enhance the powering and control of multiple arbitrarily oriented implant devices. Together, these techniques enable arbitrarily oriented implants to receive power and command, programming, and control information in an efficient manner that preserves battery life and transmission time while reducing overall implant device bulk. By steering the aggregate magnetic field from a near-orthogonal set of AC-energized coils, selected implants can be powered or communicated with at desired times. Communication with individual implants can also be enhanced through half-cycle amplitude modulation —a technique that allows bit rates up to twice the energizing frequency. Unlike prior art systems, power and data transfer can be realized over the same frequency channel.

Abstract: Magnetic Vector Steering (MVS) and Half-Cycle Amplitude Modulation (HCAM) are novel techniques which enhance the powering and control of multiple arbitrarily oriented implant devices. Together, these techniques enable arbitrarily oriented implants to receive power and command, programming, and control information in an efficient manner that preserves battery life and transmission time while reducing overall implant device bulk. By steering the aggregate magnetic field from a near-orthogonal set of AC-energized coils, selected implants can be powered or communicated with at desired times. Communication with individual implants can also be enhanced through half-cycle amplitude modulation—a technique that allows bit rates up to twice the energizing frequency. Unlike prior art systems, power and data transfer can be realized over the same frequency channel.

Abstract: Magnetic Vector Steering (MVS) and Half-Cycle Amplitude Modulation (HCAM) are novel techniques which enhance the powering and control of multiple arbitrarily oriented implant devices. Together, these techniques enable arbitrarily oriented implants to receive power and command, programming, and control information in an efficient manner that preserves battery life and transmission time while reducing overall implant device bulk. By steering the aggregate magnetic field from a near-orthogonal set of AC-energized coils, selected implants can be powered or communicated with at desired times. Communication with individual implants can also be enhanced through half-cycle amplitude modulation--a technique that allows bit rates up to twice the energizing frequency. Unlike prior art systems, power and data transfer can be realized over the same frequency channel.

Abstract: Impedance of an energized electrical line which carries electrical current at a predetermined line frequency is nondistruptively measured at frequencies which are above and below the predetermined line frequency. A measurement current is generated at a measurement frequency between, for example, 10 Hz and 30 kHz for a 60 Hz line. The current generator is coupled to the energized electrical line by an isolating circuit which blocks only the predetermined line frequency and frequencies which differ from the predetermined line frequency by substantially less than the predetermined line frequency. For example, a notch filter may be used. A current sensor measures the line current in the energized line at the measurement frequency. A voltage sensor measures the line voltage in the energized electrical line at the measurement frequency. An analyzer determines impedance of the energized line at the measurement frequency. The measurement is repeated over a wide range of frequencies above and below the line frequency.

Abstract: The present invention relates to a method and apparatus for controlling the speed of an electronically commutated motor. Such motors typically include a rotor, a stator coil, and an electronic commutator for controlling electrical power flow from an electrical power source of predetermined frequency to the stator coil.

Abstract: An inductive coupled power system has a transmission circuit with a dual primary comprising two conductor loops. First segments of the loops extend through an area served by the system adjacent each other and second segments of the loops extend through the area one on either side of the adjacent first segments. A small loop configuration minimizes the stray magnetic field. A secondary pickup assembly has a U-shaped core with two legs which embrace the first segments of the two loops and a core element adjacent the first loop segments is positioned between the ends of the legs. Each of the power circuits of a plurality of loads includes a shunt regulator.

Abstract: A tuning structure for a klystron oscillator is provided by a set of holes extending part way through cavity walls of the klystron. The holes provide weakened portions in the cavity walls which permit an inward depression of the walls at the sites of the weakened portions for adjustment of the central frequency of an oscillation band. Thereby, deformable tuning diaphragms, which are employed for altering the oscillation frequency within the oscillation band, need not be deformed for an oscillation at the center of the desired band. Variations in frequency can thereby be accomplished without metal fatigue, such fatigue having occurred when the diaphragm has been utilized for setting the central frequency of the oscillation band.