Analog Devices,inc.

Analog Devices Global

Eamon Nash

Christopher Eugene Hay

Robert J McMorrow

Peadar Antony Forbes

Mingming Zhao

Carlos Calvo

Claire Masterson

Dale Wilson

Ovidiu Vasile Balaj

A pair of programmable state machines may be included in a transmitter integrated circuit of a scanner (e.g. a body scanner) to control the sub-circuits of the transmitter integrated circuit. The first programmable state machine may be used to control the signal processor of the transmitter that facilitates generation of a signal to be transmitted at a target, such as a user to be scanned. The second programmable state machine may be used to control the transmitter's selection of a transmission channel for transmitting the signal in which provides the signal to be transmitted to an antenna. Further, the receiver integrated circuit of the scanner may include a similar pair of programmable state machines for controlling the receive signal processor and receiver of the receiver integrated circuit. The inclusion of the state machines can reduce both the scan time and the circuit complexity of the scanner.

State-machine based body scanner imaging system

Apparatus and methods are disclosed related to radio frequency (RF) power detection. One such apparatus includes a directional coupler, an RF switch, and an RF power detector. The RF switch can selectively change coupling between the directional coupler and the RF power detector. This can enable accurate power detection based on a ratio of power levels, without factory calibration or laser trimming.

Apparatus and method for detecting radio frequency power

Aspects of this disclosure relate to protecting a circuit, such as an amplifier, from transient overdrive events and/or average overdrive events. In one embodiment, an indication of average power, such as root mean squared (RMS) power of a radio frequency (RF) signal, can be compared to a first threshold and an indication of a peak RF power can be compared to a second threshold. When the indication of average power exceeds the first threshold, an average overdrive event can be detected. When the indication of peak power exceeds the second threshold, a peak overdrive event can be detected. If either a transient overdrive event or an average overdrive event is detected, a circuit, such as an amplifier, can be protected.

Power detector with overdrive detection

Described is a closed-loop power detector/controller for wireless systems employing a non-constant amplitude envelope modulation scheme. Any AM component in the feedback signal resulting from non-constant amplitude envelope signals is eliminated via feed-forward cancellation of the envelope signal. Generally, a signal representative of the AM variation in the non-constant amplitude envelope signals prior to amplification is obtained. This AM variation signal is then used to cancel any AM component in the feedback signal resulting from the non-constant envelope to create a power amplifier control signal without any AM variation, only the desired ramp profile.

Edge power detector/controller

An RMS-to-DC converter system is disclosed. The system includes a variable gain amplifier having transfer function ripple that receives an input signal and provides an amplifier output signal, a detector that receives the amplifier output signal and provides a detector output signal, an error amplifier that receives the detector output signal and provides an error amplifier output signal having an AC component, and a feedback circuit coupled to the error amplifier output signal and to the variable gain amplifier for providing a feedback signal to the variable gain amplifier that includes an AC component for reducing transfer function ripple of the RMS-to-DC converter system.

Growing community of inventors

Chicago, IL, United States of America

Eamon Nash