A transmission module includes n oscillator modules and a phase command signal generator. Each of the oscillator modules includes a voltage controlled oscillator and an amplification circuit. The voltage controlled oscillators output transmission high-frequency signals having the same frequency and synchronized among the n oscillator modules by synchronous control based on a common reference signal. The amplification circuits each perform power amplification for the transmission high-frequency signal from a corresponding one of the voltage controlled oscillators and output the resultant signal. Phases of the transmission high-frequency signals synchronized among the n oscillator modules and output from the voltage controlled oscillators are separately controlled according to respective n phase command signals from the phase command signal generator.

An amplifier for modulating the amplitude of an RF signal, the amplifier including: a plurality of amplifier circuits, each circuit being connected to a first power source, each circuit including a charge storage device and an output across which a potential difference supplied by the first power source can be applied; a switching arrangement for switching connections between the first power source, the charge storage device, and the output in each amplifier circuit, wherein each circuit includes a first switched configuration in which the charge storage device is charged by the first power source and a second switched configuration in which the charge storage device, once charged, will apply an additional potential difference across the output. The amplifier is configured to vary the amplitude of the RF signal in proportion to the sum of the potential differences applied across the output in each amplifier circuit.

A power combining and outphasing system and related techniques for simultaneously providing both wide-bandwidth linear amplification and high average efficiency is described. Providing linear amplification encompasses the ability to dynamically control an RF output power level over a wide range while still operating over a wide frequency bandwidth. The system and techniques described herein also operate to maintain high efficiency across a wide range of output power levels, such that a high average efficiency can be achieved for highly modulated output waveforms.

Provided herein are apparatus and methods for a multi-stage signal-processing circuit. The signal-processing circuit can include multiple configurable stages that can be cascaded and configured to process an input signal. Control circuitry can be used to select an output of the configurable stages. Serial data can be recovered with good signal integrity using a signal monitor with the configurable stages by virtually placing the signal monitor on a buffered output node.

A peak detector for a power amplifier is provided that includes a threshold voltage detector configured to pulse a detection current in response to an amplified output signal from the amplifier exceeding a peak threshold. A plurality of such peak detectors may be integrated with a corresponding plurality of power amplifiers in a transmitter. Should any peak detector assert an alarm signal or more than a threshold number of alarm signals during a given period, a controller reduces a gain for the plurality of power amplifiers.

An amplifier for modulating the amplitude of an RF signal, the amplifier including: a plurality of amplifier circuits, each circuit being connected to a first power source, each circuit including a charge storage device and an output across which a potential difference supplied by the first power source can be applied; a switching arrangement for switching connections between the first power source, the charge storage device, and the output in each amplifier circuit, wherein each circuit includes a first switched configuration in which the charge storage device is charged by the first power source and a second switched configuration in which the charge storage device, once charged, will apply an additional potential difference across the output. The amplifier is configured to vary the amplitude of the RF signal in proportion to the sum of the potential differences applied across the output in each amplifier circuit.

A power management circuit operable with multiple supply voltages is disclosed. In embodiments disclosed herein, the power management circuit includes a supply voltage circuit(s) capable of simultaneously generating multiple supply voltages at different voltage levels. The power management circuit also includes multiple envelope tracking (ET) voltage circuits each configured to generate a respective one of multiple ET voltages based on the multiple supply voltages. In this regard, each ET voltage circuit can dynamically use different supply voltages from time to time to generate the respective ET voltage. As a result, it is possible to prevent distortion (e.g., amplitude clipping) in any of the ET voltages, especially when large peak-to-average ratio (PAR) is expected in the ET voltages.

An apparatus comprises: a photodetector having a cathode and an anode to generate an output current; and a differential transimpedance amplifier (TIA) having a first amplifier input coupled to a first one of the cathode and the anode through a first AC coupling capacitor and a first feedforward resistor that is connected in parallel with the first AC coupling capacitor between the first one of the cathode and the anode and the first amplifier input, the differential TIA having a second amplifier input coupled to a second one of the cathode and the anode that is not the first one of the anode and the cathode, the differential TIA configured to convert the output current of the photodetector as presented at the first amplifier input and the second amplifier input to a differential output voltage.