Abstract: A high frequency data network access system leverages commodity WiFi chipsets and specifically multi spatial stream (e.g., 802.11 ac) chipsets in combination with phased array antenna systems at the aggregation nodes. Examples can be very spectrally efficient with both polarization and frequency diversity.

Abstract: The present disclosure includes multi-level switching regulator circuits and methods with finite state machine control. In one embodiment, a circuit comprises a switching regulator and a finite state machine. The switching regulator comprises high side and low side switches, and at least one capacitor. A finite state machine receiving a switching signal and a duty cycle signal to generate switch control signals to the switches. The switches are turned on and off under control of the finite state machine in response to transitions of the switching signal and the duty cycle signal. The switching signal may be generated from an envelope tracking signal, and the switching regulator may be part of an envelope tracking system.

Abstract: A modulator which has a first terminal to receive a carrier signal, a second terminal to receive a first control signal to control a frequency band of the carrier signal and a third terminal to receive a second control signal to control a modulation depth of the carrier signal.

Abstract: According to one embodiment, a digital amplitude modulator includes a power supply unit, a measurement unit, a calculation unit, and a power controller. The power supply unit supplies a power supply voltage to a plurality of power amplifiers. The measurement unit measures the output power and reflection coefficient of a synthesizer. The calculation unit calculates loss power occurring in each power amplifier in an ON state, and reflected power consumed by each power amplifier in the ON state. The power controller controls all the power amplifiers to be in an OFF state, and performs a normal operation, and controls the input voltage of the power supply unit or ON/OFF of the plurality of power amplifiers.

Abstract: An irrigation control device having a modulator that modulates data onto an alternating power signal by distorting amplitude of a first leading portion of selected cycles of the alternating power signal, and permit effectively a full amplitude of the alternating power signal on a following portion of the selected cycles, wherein the first leading portion and the following portion are either both on a high side of a cycle or both on a low side of a cycle of the alternating power signal. The irrigation control device further includes an interface configured to couple the modulator to a multi-wire interface coupled to a plurality of irrigation devices to permit the alternating power signal to be applied to the multi-wire interface.

Abstract: A reference voltage adjustment unit (212) calculates gain from a DA converter (121) to an offset calculating unit (123) by detecting the output of the offset calculating unit (123), adjusts the reference voltage (V3) from a reference voltage generation unit (211) so that the value becomes a predetermined value, and feeds the post-adjustment reference voltage (V4) to the DA converter (121) and offset calculating unit (123). Due to this, the gain from the DA converter (121) to the offset calculating unit (123) can be corrected. Fluctuation in the lower limit level of the output of a differential-to-single conversion unit (124) can be minimized as a result, so, the addition of unnecessary offset to the amplitude data at the amplifier unit (140) can be minimized. Thus, deterioration in modulation characteristics when the amplitude control unit (210) takes a differential circuit configuration can be minimized.

Abstract: An amplitude modulated pulse transmitter designed to operate across a multi MHz range of modulation frequencies. A wire wound rare earth magnet is to be utilized instead of the typical modulation transformer. Additionally, a plurality of electrolytic capacitors are also employed in the transmitter.

Abstract: A communication system using a length shift keying (LSK) modulation method provides a transmitter having a carrier signal generator for generating carrier signals, and a modulator for modulating lengths of the carrier signals from the carrier signal generator according to combinations of data bits, and a receiver having an integrator for calculating an energy value by integrating the carrier signal that corresponds to a data bit combination, and a data judgment unit for judging the data bit combination by comparing the energy value with a predetermined threshold value. Power is maintained without changing the bandwidth of a communication signal when the communication signal is modulated.

Abstract: A power management device providing a power amplifier with power supply voltage is provided. The power management unit includes a parallel-hybrid amplitude modulator apparatus having a linear part configured to track frequency components of an input signal above a determined threshold frequency and a switching part arranged in parallel with the linear part and configured to track frequency components of the input signal below the determined threshold frequency. Additionally, the power management unit includes a current sensing and controlling part configured to determine the level of a direct current component at an output of the linear part and control the switching part to produce an output signal compensating for the direct current component at the output of the linear part to decrease the absolute level of the direct current at the output of the linear part.

Abstract: The operating method is based on the simultaneous application of FM and AM. In this process, the fundamental frequency of the AM is derived from at least one, preferably the second, longitudinal mode. In continuous operation of the lamp, the color temperature is set for a prescribed power by setting the AM degree controllably.

Abstract: A quadra-polar modulator that is simple to implement and also provides good noise performance. The quadra-polar modulator includes four amplitude modulators and a combiner. Each amplitude modulator modulates a respective carrier signal with a respective input signal to provide a respective output signal. The combiner then combines the four output signals from the four amplitude modulators to provide a modulated signal. Each amplitude modulator may be implemented with a switching amplifier, such as a supply modulated class E amplifier. Two input signals are obtained by summing separately an inphase (I) modulating signal and an inverted I modulating signal with an offset value. The other two input signals are obtained by summing separately a quadrature (Q) modulating signal and an inverted Q modulating signal with the offset value. The offset value can be selected based on the expected magnitude of the modulating signals. The four carrier signals are in quadrature to each other.

Abstract: An ASK modulator including a switching diode connected in series to a carrier signal transmitting path, a first resistor connected between one end of the switching diode and a digital signal input end and a second resistor connected between one end of the switching diode and the reference voltage point. The digital signal to be applied to the digital signal input end is divided by the first and second resistors and the switching diode is turned ON and OFF to generate the ASK modulated signal with the logical level of the divided digital signal. In this case, the switching level of the switching diode rises substantially to prevent that the switching diode turns ON by the ringing phenomenon.

Abstract: A band limited Amplitude Shift Keyed (ASK) modulator employing linear modulation and an efficient Class C power amplifier. Band-limited operation is provided by filtering a digital baseband input signal prior to modulation. Closed loop feedback is employed around the amplifier to assure linear modulation over a wide modulation range which preserves the frequency characteristics of the baseband signal on the modulation envelope. Further filtering is accomplished by exploiting the closed loop system response, incorporating it in the filter characteristic as an added filter pole.

Abstract: A time-division multiplex signal transmission system includes a transmitter having a power amplifier with a control input to which is supplied a control voltage (U.sub.c). The power of the amplifier high-frequency output signal (RF.sub.out) is detected by a detector which produces a detector voltage representing the sum of a detector quiescent voltage (U.sub.o) and an actual detected signal voltage (U.sub.ist). The control voltage (U.sub.c) is generated from the difference between the detector voltage (U.sub.o +U.sub.ist) and a nominal voltage (U.sub.soll) which is superimposed on the detector quiescent voltage (U.sub.o). The nominal voltage (U.sub.soll) determines the waveform of the power of the output signal (RF.sub.out).

Abstract: A gain control circuit for a radio transmitter, such as the radio transmitter portion of a radiotelephone operative to transmit a .pi./4 DQPSK-modulated signal in discrete bursts. The signal portion of the signal transmitted during each discrete burst forms a slot and at least one of the slots includes a pre-determined data sequence portion. The peak power level of the portion of the slot comprising the pre-determined data sequence portion, once amplified by amplifier circuitry of the radiotelephone, is compared with a stored value representative of the peak power level of a corresponding portion of a slot amplified to be of a desired signal level. Responsive to such comparison, the amplification level of the amplifier circuitry is altered.