RFID range improvement technology

This current offering came to us from an acquisition of a sponge counting system for the hospital Operating Room which relied on an RFID reader that identified tagged surgical sponges through the human body and still meet the FCC restrictions for power levels to interrogate a tag. This novel feature of an RFID reader may improve the read range by 10-25%. 

Patent family includes granted US matters: US 9,041,479 (attached), US 9,425,741 and US 9,614,478


The technology relates generally to signal processing and more particularly to switchmode RF power amplifiers. The patent describes systems and methods for providing an amplitude modulation signal to a switchmode amplifier. A DC to DC switch may be configured to receive a DC input voltage at one level and to provide a DC output voltage at a different level at high efficiency. A low dropout regulator (LDO) may be configured to provide the amplitude modulation signal according to a modulation control signal received by the low dropout regulator, the low dropout regulator being powered by the DC output voltage. A control circuit may be connected to the DC to DC switch and the low dropout regulator, where the control circuit is configured to establish a nominal operating power level for the power amplifier via the amplitude modulation signal and to maintain a minimum voltage difference between the DC output voltage and LDO output. A modulator control circuit may be configured to provide the modulation control signal to the low dropout regulator, the modulation control signal including transitions from a high amplitude to a low amplitude back to a high amplitude, where the modulator control circuit provides the transition from the high amplitude to the low amplitude at a configurable first slope, and the modulator control circuit provides the transition from the low amplitude to the high amplitude at a configurable second slope.