Abstract: A Time Domain Return measurement system for measuring liquid level, linear movement or other measurements which includes a first and second electrode, the second electrode spaced from the first electrode to define a gap, and an electronics assembly connected to the first and second electrodes equipped with a generator for transmitting an electromagnetic signal for propagation along the electrodes. The signal generator has a first analog timing circuit for actuating a slow-rising function of voltage versus time, a second analog timing circuit associated with the first analog timing circuit for actuating a fast-rising function of voltage versus time, and a receive circuit electrically connected to the electrodes, the receive circuit being activated for receiving return echo data associated with the electromagnetic signal transmitted when the fast-rising function is equal or greater than the slow-rising function to determine the position of the second medium with respect to the electrodes.

Abstract: A time domain reflectometer (TDR) transducer (10) for determining a level (24) of liquid (16) in a container (12) includes a first electrode (34) and a second electrode portion (36) with a measuring volume (114) therebetween for receiving material (16) to be measured. The second electrode portion (36) has a shielded electrode section (36A) isolated from the first electrode (34) and an unshielded electrode section (36B), such that an energy pulse propagates along the shielded electrode section (36A) without signal loss, and boomerangs along a second opposite direction across the first conductive electrode portion (34), the measuring volume (114) and the unshielded electrode section (36B) where partial reflection of the pulse occurs at least at the interface (24) of the material (16) to create a return echo that travels in reverse direction, boomeranging back through the shielded electrode section (36A) for analysis by an electronic assembly (32).

Abstract: A Time Domain Return measurement system for measuring liquid level, linear movement or other measurements which includes a first and second electrode, the second electrode spaced from the first electrode to define a gap, and an electronics assembly connected to the first and second electrodes equipped with a generator for transmitting an electromagnetic signal for propagation along the electrodes. The signal generator has a first analog timing circuit for actuating a slow-rising function of voltage versus time, a second analog timing circuit associated with the first analog timing circuit for actuating a fast-rising function of voltage versus time, and a receive circuit electrically connected to the electrodes, the receive circuit being activated for receiving return echo data associated with the electromagnetic signal transmitted when the fast-rising function is equal or greater than the slow-rising function to determine the position of the second medium with respect to the electrodes.

Abstract: A Time Domain Return measurement system for measuring liquid level, linear movement or other measurements which includes a first and second electrode, the second electrode spaced from the first electrode to define a gap, and an electronics assembly connected to the first and second electrodes equipped with a generator for transmitting an electromagnetic signal for propagation along the electrodes. The signal generator has a first analog timing circuit for actuating a slow-rising function of voltage versus time, a second analog timing circuit associated with the first analog timing circuit for actuating a fast-rising function of voltage versus time, and a receive circuit electrically connected to the electrodes, the receive circuit being activated for receiving return echo data associated with the electromagnetic signal transmitted when the fast-rising function is equal or greater than the slow-rising function to determine the position of the second medium with respect to the electrodes.

Abstract: A Time Domain Return measurement system for measuring liquid level, linear movement or other measurements which includes a first and second electrode, the second electrode spaced from the first electrode to define a gap, and an electronics assembly connected to the first and second electrodes equipped with a generator for transmitting an electromagnetic signal for propagation along the electrodes. The signal generator has a first analog timing circuit for actuating a slow-rising function of voltage versus time, a second analog timing circuit associated with the first analog timing circuit for actuating a fast-rising function of voltage versus time, and a receive circuit electrically connected to the electrodes, the receive circuit being activated for receiving return echo data associated with the electromagnetic signal transmitted when the fast-rising function is equal or greater than the slow-rising function to determine the position of the second medium with respect to the electrodes.

Abstract: A time domain reflectometer (TDR) transducer (10) for determining a level (24) of liquid (16) in a container (12) includes a first electrode (34) and a second electrode portion (36) with a measuring volume (114) therebetween for receiving material (16) to be measured. The second electrode portion (36) has a shielded electrode section (36A) isolated from the first electrode (34) and an unshielded electrode section (36B), such that an energy pulse propagates along the shielded electrode section (36A) without signal loss, and boomerangs along a second opposite direction across the first conductive electrode portion (34), the measuring volume (114) and the unshielded electrode section (36B) where partial reflection of the pulse occurs at least at the interface (24) of the material (16) to create a return echo that travels in reverse direction, boomeranging back through the shielded electrode section (36A) for analysis by an electronic assembly (32).

Abstract: A transducer for determining the level of liquid within a container includes a mounting head for connection to the container; a senor tube extending from the mounting head; a substrate located in the sensor tube; at least one sensor positioned on the substrate for sensing a level of liquid within the container; and a float constrained to move along the sensor tube. The float has an actuator for changing an electrical state of the sensor to thereby indicate liquid level. At least one damping section having at least one damping beam integrally formed with the substrate is normally in contact with a surface associated with the sensor tube and is movable toward and away from the substrate to dampen forces acting on the transducer and thus on the at least one sensor. An electronic assembly with integral damping sections is also described.

Abstract: This invention teaches a way to multiplex and de-multiplex unipolar signals using spread spectrum methods. While bipolar spread spectrum signal multiplexing may be used in may applications, for example for systems using radio signals, when using unipolar signals there is a loss of orthogonally which makes the standard algorithms unworkable. This invention teaches a method to recover orthogonally and make spread spectrum multiplexing useful for unipolar signals. One example is in the measurement of optical absorbance along multiple paths simultaneously using light signals, as for functional near infrared spectroscopy (fNIRS).

Abstract: This invention teaches a way to multiplex and de-multiplex unipolar signals using spread spectrum methods. While bipolar spread spectrum signal multiplexing may be used in may applications, for example for systems using radio signals, when using unipolar signals there is a loss of orthogonally which makes the standard algorithms unworkable. This invention teaches a method to recover orthogonally and make spread spectrum multiplexing useful for unipolar signals. One example is in the measurement of optical absorbance along multiple paths simultaneously using light signals, as for functional near infrared spectroscopy (fNIRS).