Abstract:
A fiber laser having a thermal controller operatively connected to one or more fiber Bragg gratings is provided. The thermal controller does not impart much or imparts very little mechanical stress or strain to the optical fiber in which the FBGs reside because such forces can alter the FBG performance. Rather, the thermal controller utilizes a thermally conductive semi-solid or non-Newtonian fluid to submerge/suspend a portion of the optical fiber in which FBG resides. Temperature control logic controls whether a thermoelectric heater and cooler should be directed to increase or decrease its temperature. The thermoelectric heater and cooler imparts or removes thermal energy from the FBG to efficiently control its performance without the application of mechanical stress. The fiber laser having a thermal controller generally is able to increase laser output power greater than two times the amount of output power of a similarly fabricated fiber laser free of the thermal controller(s).
Abstract:
Techniques are provided for a switched output digital to analog converter employing an N-path cascode output switch. An example system may include a plurality of cascode transistors coupled in parallel to an output stage of a current mode digital to analog converter (DAC) circuit. The system may also include a plurality of control ports, each of the control ports coupled to a gate of one of the cascode transistors. The system may further include a plurality of output ports, each output port coupled to one of the cascode transistors. The cascode transistors are configured to switch the output stage of the DAC to the output port of the transistor in response to a routing control signal applied to the control port of the transistor. The cascode transistors are High Electron Mobility Transistors (HEMT) fabricated from Gallium Nitride.
Abstract:
A laser range finder (LRF) and an automated method for determining a return laser signal associated with a target thereof are disclosed. In one example embodiment, the LRF includes a laser beam emitter to emit a laser beam towards a target. Further, the LRF includes a receiver circuit to receive multiple return laser signals reflected from objects including the target and to determine an amplitude of each of the multiple return laser signals. Furthermore, the LRF includes a processor coupled to the receiver circuit to compare the amplitude of each of the multiple return laser signals with a range varying threshold that accounts for range and atmospheric losses and to determine one of the multiple return laser signals as being associated with the target based on the comparison.
Abstract:
A scene correlation-based target system and related methods are provided. A reference image depicts a remotely-positioned object having identifiable characteristics, wherein a reference directional vector is established relative to the reference image. A target image of a general vicinity of the remotely-positioned object has an unknown directional vector, the target image having at least a portion of the identifiable characteristics. An inertial measuring unit has a scene correlation system, wherein the scene correlation system matches the portion of the identifiable characteristics of the target image with the identifiable characteristics of the reference image, wherein a slew angle between the reference image and the target image is calculated. A target image directional vector is derived from the calculated slew angle and the reference directional vector.
Abstract:
An apparatus for managing data queues is disclosed. The apparatus includes at least one sensor for collecting data, a data interface for receiving data from the sensor(s) and for placing the collected data in a set of data queues, and a priority sieve for organizing the set of data queues according to data priority of a specific task. The priority sieve includes a scoreboard for identifying queue priority and a system timer for synchronization.
Abstract:
A flash memory process and device for encrypting and storing data in a non-volatile flash memory associated with a host system. The device includes a flash memory, an encryption engine, a key store, a SRAM to interface with the host system, and associated control circuitry. When powered on, the device first determines if a valid encryption key is held in the key store. If a valid key is held in the store, a program flag is set when encrypted data in the flash memory is ready to be decrypted by the engine and Random stored in the SRAM for use by the host system, or when data originating from the host system and stored in the SRAM is ready to be encrypted by the engine and programmed into the flash memory. The device can be embedded in any host system wherein data must be encrypted while at rest in a memory.
Abstract:
A method and apparatus of detecting laser in a laser warning receiver is disclosed. A panoramic lens assembly utilized in cameras is combined with a laser detection focal plane. Incident laser light is refracted in the panoramic lens and made to illuminate a multiplicity of individual sensor elements. By determining the corresponding intensity of the laser light on the sensors, the angle of arrival resolutions superior to the element angular resolutions can be achieved. The combination of a panoramic lens with a laser detection focal plane provides a low cost laser warning for wrap around ground based situational awareness.
Abstract:
A specific emitter identification (SEI) method and apparatus is capable of identifying and tracking objects within a geographical area of interest wherein the system and method has not been preprogrammed to look for particular signals. The system and method receives all of the emitted electromagnetic signals emitted from area of interest. The system and method next performs high order statistical analysis on the received signals and determines which signals emanate from possible targets of interest and which likely emanate from background clutter/noise by comparing the relative degrees of Gaussianness of the signals (for example using entropy measurements). The least Gaussian signals are deemed to likely be signals from potential targets of interest while those which are more Gaussian are deemed to be likely from background clutter or noise.
Abstract:
Techniques are provided for a switched output digital to analog converter employing an N-path cascode output switch. An example system may include a plurality of cascode transistors coupled in parallel to an output stage of a current mode digital to analog converter (DAC) circuit. The system may also include a plurality of control ports, each of the control ports coupled to a gate of one of the cascode transistors. The system may further include a plurality of output ports, each output port coupled to one of the cascode transistors. The cascode transistors are configured to switch the output stage of the DAC to the output port of the transistor in response to a routing control signal applied to the control port of the transistor. The cascode transistors are High Electron Mobility Transistors (HEMT) fabricated from Gallium Nitride.
Abstract:
A method for polishing photonic chips is described. A gauge is placed in a photonic chip adjacent to an edge to be polished. The gauge includes a set of bars of various lengths. The bar lengths can be progressively ordered from shortest to longest or vice versa. The photonic chip is then secured in a chip polishing jig to get ready for polishing. When the photonic chip is being polished, an operator can visually inspect the gauge by looking at the polishing edge to estimate a polishing depth in order to determine a stopping point for polishing. Once the stopping point has been reached, the polishing of the photonic chip can be stopped.