According to one aspect, an uninterruptible power supply system is provided including an input configured to receive input power, an interface configured to be coupled to a backup power supply and to receive backup power from the backup power supply, an output configured to provide output power derived from at least one of the input power and the backup power to a load, a power converter coupled to the input, a capacitor, and a shoot-through detector coupled to the capacitor. The shoot-through detector is configured to obtain a first voltage value indicative of a first voltage across the capacitor, obtain a second voltage value indicative of a second voltage across the capacitor, compare the first voltage value to the second voltage value, determine, based on the comparison, that the capacitor is experiencing a shoot-through condition, and provide an output signal indicative of the shoot-through condition.

According to one aspect, an uninterruptible power supply system is provided including an input configured to receive input power, an interface configured to be coupled to a backup power supply and to receive backup power from the backup power supply, an output configured to provide output power derived from at least one of the input power and the backup power to a load, a power converter coupled to the input, a capacitor, and a shoot-through detector coupled to the capacitor. The shoot-through detector is configured to obtain a first voltage value indicative of a first voltage across the capacitor, obtain a second voltage value indicative of a second voltage across the capacitor, compare the first voltage value to the second voltage value, determine, based on the comparison, that the capacitor is experiencing a shoot-through condition, and provide an output signal indicative of the shoot-through condition.

A signal analysis circuit for determining whether a supplying-end module of an induction type power supply system receives a modulation signal from a receiving-end module includes a signal receiving circuit, a gain amplifier, a ramp generator, a comparator, a timer and a processor. The signal receiving circuit is configured to obtain a coil signal on a supplying-end coil of the supplying-end module. The gain amplifier is configured to adjust a voltage level of the coil signal to generate an amplification signal. The ramp generator is configured to generate and output a ramp signal. The comparator is configured to compare the amplification signal with the ramp signal to determine a trigger time on which the amplification signal and the ramp signal intersect. The timer is configured to obtain a time data corresponding to the trigger time. The processor is configured to analyze the modulation signal according to the time data.

An electronic envelope detection circuit includes an input signal detecting circuit having at least one MOS transistor configured to receive a radiofrequency input signal and to deliver an internal signal on the basis of the input signal. The biasing point of the at least one transistor is controlled by the input signal and a control signal. A processing circuit that is coupled to the input signal detecting circuit is configured to deliver a low-frequency output signal on the basis of the internal signal and further deliver the control signal on the basis of the output signal. In operation, the value of the control signal decreases when the average power of the input signal increases, and vice versa.

An electronic envelope detection circuit includes an input signal detecting circuit having at least one MOS transistor configured to receive a radiofrequency input signal and to deliver an internal signal on the basis of the input signal. The biasing point of the at least one transistor is controlled by the input signal and a control signal. A processing circuit that is coupled to the input signal detecting circuit is configured to deliver a low-frequency output signal on the basis of the internal signal and further deliver the control signal on the basis of the output signal. In operation, the value of the control signal decreases when the average power of the input signal increases, and vice versa.

A system, method and computer program product for optimizing an antenna pattern for a booster, in which input signals from different operators are transmitted at different carrier frequencies within an operating bandwidth. An input bandwidth of a plurality of input signals are monitored at an input of the booster, the input bandwidth being within the operating bandwidth. One or more peak signal levels of the plurality of input signals within the input bandwidth are detected. Each of the detected one or more peak signal levels of the plurality of input signals at the input of the booster are then adjusted, such that a peak signal level of each of the plurality of input signals are substantially equal.

A system, method and computer program product for optimizing an antenna pattern for a booster, in which input signals from different operators are transmitted at different carrier frequencies within an operating bandwidth. An input bandwidth of a plurality of input signals are monitored at an input of the booster, the input bandwidth being within the operating bandwidth. One or more peak signal levels of the plurality of input signals within the input bandwidth are detected. Each of the detected one or more peak signal levels of the plurality of input signals at the input of the booster are then adjusted, such that a peak signal level of each of the plurality of input signals are substantially equal.

An MPU sequentially selects one from six energization patterns, applies constant voltage rectangular pulses to the three-phase coils for a prescribed sensing energization time, turns on at least the low-side arm of the three-phase half-bridge type inverter circuit so as to reflux an induced current between a switching element and the coils and attenuate the same, measures peak coil current values immediate before completing the sensing energization by an A/D-converter circuit, and stores the peak coil current values as measured data.

An MPU sequentially selects one from six energization patterns, applies constant voltage rectangular pulses to the three-phase coils for a prescribed sensing energization time, turns on at least the low-side arm of the three-phase half-bridge type inverter circuit so as to reflux an induced current between a switching element and the coils and attenuate the same, measures peak coil current values immediate before completing the sensing energization by an A/D-converter circuit, and stores the peak coil current values as measured data.

A method and apparatus to detect breaks in tracks and/or detect the presence of a vehicle, such as a train, in a monitored section of the track or rail. Embodiments of the present invention measure the change in track inductance associated with a track or rail break. Electrical shunts are connected between the rails at spaced-apart intervals (for example a shunt can be placed every mile). At least two different frequencies of alternating current are generated and fed into the segments of rail (for example at or near a mid-point between the shunts). If a rail break occurs, the total inductance of the rail at that segment will change. Using two or more frequencies allows a rail break to be differentiated from environmental rail-to-rail and rail-to-earth leakage.