Abstract: An oscillator assembly which, in one embodiment, is an ovenized crystal oscillator assembly including an enclosure defined by a base and a lid which is seated on the base. The components of the oscillator assembly are supported by the base and located under the lid. The base and the lid together define an interior oven and are both preferably made of an insulative thermoplastic material to maximize the heat retention and oven performance of the oscillator assembly. In one embodiment, the lid and the base incorporate a clip for securing the lid to the base.

Abstract: An imaging system for generating a three dimensional image of tissue of a patient is provided. The imaging system comprises of a transmitter, receiver, antenna system and a display element to form a synthetic aperture radar system that displays a three dimensional view of the tissue. The SAR system has been configured to operate in the near field as opposed to current equipment which can only perform satisfactorily in the far field. A calibration technique has been utilized that allows the system to perform as well as other systems that operate using far field techniques but allows for a much simpler, cost effective system.

Abstract: An oscillator assembly includes a substrate having a top surface, a bottom surface, and a plurality of side surfaces. At least one of the side surfaces has at least one castellation which is covered with conductive material and includes a lower end spaced from the bottom surface of the substrate. The space is defined by an elongate groove in the side surface which is devoid of conductive material and extends between the lower end of the castellation and the bottom surface of the substrate to eliminate the risk of a short circuit with any of the connection pads on a customer's motherboard. The oscillator assembly further incorporates an oscillator circuit in which a current limiting resistor is located in series between the power supply and the heater control circuit.

Abstract: An oscillator assembly including an oscillator seated on a pad of thermally conductive material formed on the surface of a printed circuit board and covered by a lid defining an oven for the oscillator. In one embodiment, a plurality of heaters are located on different sides of the oscillator and at least partially seated on the pad for evenly transferring heat to the pad and the oscillator. In one embodiment, the oscillator is a temperature compensated crystal oscillator and an integrated amplifier controller circuit on the printed circuit board integrates at least one operational amplifier for controlling the heater(s) and one or more transistors for providing heat to the oven. A canopy seated on the pad and covering the oscillator can be used for transferring heat more evenly to the oscillator. A cavity in the bottom of the printed circuit board defines an insulative air pocket.

Abstract: An oscillator assembly which, in one embodiment, is an ovenized crystal oscillator assembly including an enclosure defined by a base and a lid which is seated on the base. The components of the oscillator assembly are supported by the base and located under the lid. The base and the lid together define an interior oven and are both preferably made of an insulative thermoplastic material to maximize the heat retention and oven performance of the oscillator assembly. In one embodiment, the lid and the base incorporate a clip for securing the lid to the base.

Abstract: An oscillator having improved frequency stability which includes an oscillator circuit and an SC-cut resonator connected with the oscillator circuit. The SC-cut resonator has a first turning point. A temperature compensation circuit is connected with the oscillator circuit. The temperature compensation circuit is adapted to adjust a reference frequency generated by the oscillator circuit according to a frequency response associated with a second turning point of an AT-cut resonator.

Abstract: An oscillator assembly includes a substrate having a top surface, a bottom surface, and a plurality of side surfaces. At least one of the side surfaces has at least one castellation which is covered with conductive material and includes a lower end spaced from the bottom surface of the substrate. The space is defined by an elongate groove in the side surface which is devoid of conductive material and extends between the lower end of the castellation and the bottom surface of the substrate to eliminate the risk of a short circuit with any of the connection pads on a customers motherboard. The oscillator assembly further incorporates an oscillator circuit in which a current limiting resistor is located in series between the power supply and the heater control circuit.

Abstract: An oscillator includes an oscillator circuit and a resonator that produces an output frequency. A temperature compensation circuit is coupled to the oscillator circuit. The temperature compensation circuit stabilizes the output frequency in response to changes in temperature. At least one temperature sensor and a temperature sensor signal modification circuit are coupled to the temperature compensation circuit. The temperature sensor signal modification circuit receives a temperature signal from the temperature sensor and generates a modified temperature sensor signal that is transmitted to the temperature compensation circuit.

Abstract: An imaging system for generating a three dimensional image of tissue of a patient is provided. The imaging system comprises of a transmitter, receiver, antenna system and a display element to form a synthetic aperture radar system that displays a three dimensional view of the tissue. The SAR system has been configured to operate in the near field as opposed to current equipment which can only perform satisfactorily in the far field. A calibration technique has been utilized that allows the system to perform as well as other systems that operate using far field techniques but allows for a much simpler, cost effective system.

Abstract: An oscillator assembly including an oscillator seated on a pad of thermally conductive material formed on the surface of a printed circuit board and covered by a lid defining an oven for the oscillator. In one embodiment, a plurality of heaters are located on different sides of the oscillator and at least partially seated on the pad for evenly transferring heat to the pad and the oscillator. In one embodiment, the oscillator is a temperature compensated crystal oscillator and an integrated amplifier controller circuit on the printed circuit board integrates at least one operational amplifier for controlling the heater(s) and one or more transistors for providing heat to the oven. A canopy seated on the pad and covering the oscillator can be used for transferring heat more evenly to the oscillator. A cavity in the bottom of the printed circuit board defines an insulative air pocket.

Abstract: An oscillator having improved frequency stability which includes an oscillator circuit and an SC-cut resonator connected with the oscillator circuit. The SC-cut resonator has a first turning point. A temperature compensation circuit is connected with the oscillator circuit. The temperature compensation circuit is adapted to adjust a reference frequency generated by the oscillator circuit according to a frequency response associated with a second turning point of an AT-cut resonator.

Abstract: An oscillator having improved frequency stability which includes an oscillator circuit and an SC-cut resonator connected with the oscillator circuit. The SC-cut resonator has a first turning point. A temperature compensation circuit is connected with the oscillator circuit. The temperature compensation circuit is adapted to adjust a reference frequency generated by the oscillator circuit according to a frequency response associated with a second turning point of an AT-cut resonator.

Abstract: An oscillator assembly includes an oscillator circuit that is configured to generate a frequency signal. A temperature compensation circuit is in communication with the oscillator circuit and adapted to adjust the frequency signal in response to changes in temperature. The oscillator and temperature compensation circuits are located within an oven. A heater and a temperature sensor in communication with the heater are also both located in the oven. The temperature sensor is adapted to directly control the heater in response to changes in temperature. In one embodiment, the oscillator components are mounted to a ball grid array substrate which, in turn, is mounted on a printed circuit board. In this embodiment, a resonator overlies the ball grid array substrate and a lid covers and defines an oven and enclosure for the resonator and the ball grid array substrate. The oscillator and temperature compensation circuit are defined on the ball grid array substrate.

Abstract: An oscillator having improved frequency stability which includes an oscillator circuit and an SC-cut resonator connected with the oscillator circuit. The SC-cut resonator has a first turning point. A temperature compensation circuit is connected with the oscillator circuit. The temperature compensation circuit is adapted to adjust a reference frequency generated by the oscillator circuit according to a frequency response associated with a second turning point of an AT-cut resonator.

Abstract: An improved temperature compensated quartz oscillator, which includes a package for mounting compensating circuitry over a cavity instead of on a planar layer, reduces the chip failure rate by preventing undesired contact of the compensation circuitry with the material forming the layer upon which the circuitry is mounted.

Abstract: An improved temperature compensated quartz oscillator, which includes a package for mounting compensating circuitry over a cavity instead of on a planar layer, reduces the chip failure rate by preventing undesired contact of the compensation circuitry with the material forming the layer upon which the circuitry is mounted.

Abstract: This invention discloses a DME which employes an improved technique for validating received replies. The technique employed reduces lock-on time by analyzing all of the range data received within a set time period following the transmission of an interrogation pulse pair rather than just one range figure for each interrogation cycle. The DME also provides improved accuracy and reliability by varying the width of the range gate used in analyzing the received range data in accordance with the time difference between the two interrogation cycles from which range data is being compared with system status, i.e., whether the system is in the locked position or not.