Abstract: Systems and methods for obtaining telemetry environmental readings from within an electromagnetic-absorbing material are disclosed herein. The system may include a self-contained power source powering a switch-mode amplifier to drive a multi-turn coil to be driven with a low-frequency carrier.

Abstract: A sensor location method includes placing an environmental sensor within an electromagnetic-absorbing material. The sensor is configured to sense a condition of the material and output sensor data representing the condition. The method includes providing a modulator configured to encode the sensor data onto a carrier at a carrier frequency. The method includes providing an amplifier, including a switch and a load network, in communication with a multi-turn coil. The switch can transition between on and off states. The network is coupled to the switch and the first multi-turn coil and includes a terminal that receives a voltage. The network is tunable to form a resonant circuit at the carrier frequency. The method includes generating a beacon signal whose amplitude is adjustable. The method includes receiving the beacon by a receiver outside of the material, measuring the received beacon amplitude, and determining the sensor location based upon the measured amplitude.

Abstract: In an embodiment, a circuit includes a resonant portion, a plurality of switches, a first impedance, an amplifier, and a demodulator. The resonant portion includes a single RF coil and is configured for transmission/reception at about the same frequency. The switches include first, second, and third switches. The first switch includes an input in communication with a power source and an output in communication with ground. The second switch includes an input between the power source and the first switch and an output in communication with a resonant portion input. The third switch includes an input in communication with a resonant portion output and an output in communication with ground. The first impedance is between the resonant portion output and the third switch input. The amplifier includes an input between the first impedance and the third switch input. The demodulator includes an input in communication with the amplifier output.

Abstract: In an embodiment, a circuit includes a resonant portion, a plurality of switches, a first impedance, an amplifier, and a demodulator. The resonant portion includes a single RF coil and is configured for transmission/reception at about the same frequency. The switches include first, second, and third switches. The first switch includes an input in communication with a power source and an output in communication with ground. The second switch includes an input between the power source and the first switch and an output in communication with a resonant portion input. The third switch includes an input in communication with a resonant portion output and an output in communication with ground. The first impedance is between the resonant portion output and the third switch input. The amplifier includes an input between the first impedance and the third switch input. The demodulator includes an input in communication with the amplifier output.

Abstract: Systems and methods for obtaining telemetry environmental readings from within an electromagnetic-absorbing material are disclosed herein. The system may include a self-contained power source powering a switch-mode amplifier to drive a multi-turn coil to be driven with a low-frequency carrier.

Abstract: Systems and methods for obtaining telemetry environmental readings from within an electromagnetic-absorbing material are disclosed herein. The system may include a self-contained power source powering a switch-mode amplifier to drive a multi-turn coil to be driven with a low-frequency carrier.

Abstract: Systems and methods for obtaining telemetry environmental readings from within an electromagnetic-absorbing material are disclosed herein. The system may include a self-contained power source powering a switch-mode amplifier to drive a multi-turn coil to be driven with a low-frequency carrier.

Abstract: An improved bridge circuitry is presented for improved soil sensor measurements. The improved bridge circuitry may include blocking capacitors, the ability to apply bias voltage, and the substitution of AC meters with DC meters and other improvements.

Abstract: An improved bridge circuitry is presented for improved soil sensor measurements. The improved bridge circuitry may include blocking capacitors, the ability to apply bias voltage, and the substitution of AC meters with DC meters and other improvements.