Abstract: A method and system for estimation of inertial sensor errors is provided. The method includes receiving first inertial output data from a master inertial measurement unit (IMU) mounted on a host platform, with the first inertial output data comprising a change in velocity (delta V) and a change in angle (delta theta), and receiving second inertial output data from a remote IMU mounted on the host platform at a predetermined fixed distance from the master IMU, with the second inertial output data comprising a delta V and a delta theta. The first inertial output data is compared with the second inertial output data to determine a difference between the delta V of the first inertial output data and the delta V of the second inertial output data, and to determine a difference between the delta theta of the first inertial output data and the delta theta of the second inertial output data. The determined differences are applied to estimate inertial sensor errors in the remote IMU.

Abstract: An improved MEMS device and method of making. Channels are formed in a first substrate around a plurality of MEMS device areas previously formed on the first substrate. Then, a plurality of seal rings are applied around the plurality of MEMS device areas and over at least a portion of the formed channels. A second substrate is attached to the first substrate, then the seal ring surrounded MEMS device areas are separated from each other. The channels include first and second cross-sectional areas. The first cross-sectional area is sized to keep saw debris particles from entering the MEMS device area.

Abstract: A method and system for reducing the overall noise floor in a wireless communication system, subsystem or network are disclosed, which reduces the output gain levels of specific uplink antenna transmitters during non-signal time periods (e.g., rest mode) when no communication signals are being conveyed between the mobile unit(s) and base station involved. The output gain level of each such uplink antenna's transmitter is decreased by a predetermined amount, which reduces the noise contribution of that uplink antenna, but also maintains the gain at a high enough level so that a signal can still pass from a mobile unit to the base station via that link, for example, during a call initiation attempt.

Abstract: A Micro-Electro-Mechanical Systems (MEMS) inertial sensor systems and methods are operable to determine linear acceleration and rotation. An exemplary embodiment applies a first linear acceleration rebalancing force via a first electrode pair to a first proof mass, applies a second linear acceleration rebalancing force via a second electrode pair to a second proof mass, applies a first Coriolis rebalancing force via a third electrode pair to the first proof mass, applies a second Coriolis rebalancing force via a fourth electrode pair to the second proof mass, determines a linear acceleration corresponding to the applied first and second linear acceleration rebalancing forces, and determines a rotation corresponding to the applied first and second Coriolis rebalancing forces.

Abstract: A fiber optic gyroscope includes a light source, a coupler coupled to the light source, a photodetector coupled to the coupler, an integrated optic circuit (IOC) coupled to the coupler by a first element, and a sensing loop coupled to the IOC by second and third elements. At least one of the first, second and third elements includes a polarizing element.

Abstract: A method and system for obstacle mapping for navigation of an autonomous vehicle is disclosed. The method comprises providing an autonomous vehicle with an image capturing device, and focusing the image capturing device at a predetermined number of different specified distances to capture an image at each of the specified distances. The method further comprises identifying which regions in the captured images are in focus, and assigning a corresponding lens-focus distance to each of the regions that are in focus. A composite image is formed from the captured images, with each of the regions labeled with the corresponding lens-focus distance. A three-dimensional obstacle map is then produced from the composite image. The three-dimensional obstacle map has an x, y, z coordinate system, with x being proportional to pixel horizontal position, y being proportional to pixel vertical position, and z being the lens-focus distance.

Abstract: An inertial navigation system which includes a first control system and a second control system is described. The first control system is configured to estimate a vertical velocity based in part on received vertical acceleration data. The second control system is configured to receive the estimated vertical velocity from the first control system and determine a compensated vertical velocity utilizing the estimated vertical velocity and airspeed.

Abstract: An architecture is provided for coupling wireless local area network (WLAN) signals between an internetworking device and a remotely located access point using a transport network. The access point is coupled to the transport network for communicating with the internetworking device. The access point includes a wireless local area network (WLAN) access point and an access point remote converter. The WLAN access point receives wireless local area network signals from wireless computing equipment and converts such signals to local area network compatible signals. The access point remote converter receives the local area network compatible signals from the WLAN access point and converts the signals to transport modulated format signals suitable for transmission over the transport network. The transport network also provides a power signal to power at least some components of the access point.

Abstract: Methods and systems for reducing a leakage component of a received-signal are disclosed. A transmit antenna of a radar system transmits a transmit-signal including a transmit component. A receive antenna of the radar system receives a received-signal including a leakage component and a target component. The received-signal corresponds to the transmit-signal. An overlap determination is made to determine whether the target component overlaps the leakage component and/or is received during a time when the leakage component is expected to be received. If overlap exists, a reduction leakage component (e.g., a previously determined reduction leakage component) is subtracted from the received-signal so as to produce a modified received-signal, the modified received-signal including the target component and substantially excluding the leakage component.

Abstract: This invention provides a system and method for autonomously tracking a moving target from unmanned aerial vehicles (UAVs) with a variety of airframe and sensor payload capabilities so that the target remains within the vehicle's sensor field of view regardless of the specific target motion patterns. The invention uses information about target location, UAV platform type and states, sensor payload capability, and ratio of target-to-UAV speeds to select from a suite of sub-algorithms, each of which generates desired platform positions (in form of waypoints) and/or sensor orientation commands to keep the target in view.

Abstract: A transponder-based beacon transmitter system in an unmanned aerial vehicle is provided. The transponder-based beacon transmitter system comprises a global positioning system interface communicatively coupled to receive position information indicative of a current location of the unmanned aerial vehicle, a message formatter communicatively coupled to the global positioning system interface, and a transponder-based beacon transmitter. The message formatter formats vehicle identification of the unmanned aerial vehicle and the position information indicative of the current location of the unmanned aerial vehicle into an automatic dependent surveillance broadcast mode-select squitter message. The message formatter operates in one of a military mode, a National Airspace System mode, and a combined military/National Airspace System mode. The transponder-based beacon transmitter transmits the automatic dependent surveillance broadcast mode-select squitter messages from the unmanned aerial vehicle.

Abstract: System and methods for providing a recoverable real time multi-tasking computer system are disclosed. In one embodiment, a system comprises a real time computing environment, wherein the real time computing environment is adapted to execute one or more applications and wherein each application is time and space partitioned. The system further comprises a fault detection system adapted to detect one or more faults affecting the real time computing environment and a fault recovery system, wherein upon the detection of a fault the fault recovery system is adapted to restore a backup set of state variables.

Abstract: A physic package for an atomic clock comprising: a block made of optical glass, a glass ceramic material or another suitable material that includes a plurality of faces on its exterior and a plurality of angled borings that serve as a vacuum chamber cavity, light paths and measurement bores; mirrors fixedly attached using a vacuum tight seal to the exterior of the block at certain locations where two light paths intersect; optically clear windows fixedly attached using a vacuum tight seal to the block's exterior over openings of the measurement bores and at one location where two light paths intersect; and fill tubes fixedly attached using a vacuum tight seal to the exterior of the block over the ends of the vacuum chamber cavity. This physics package design makes possible atomic clocks having reduced size and power consumption and capable of maintaining an ultra-high vacuum without active pumping.

Abstract: A wireless distribution system includes a number of remote units distributed in a coverage area to receive wireless signals and to provide the signals through the distribution system to input ports of a node where the signals are combined, a number of input power monitors operatively connected to one or more of the input ports to determine power levels of signals received at the input ports, variable gain controllers to control signals received at some or all of the input ports, a node to combine a plurality of signals from the plurality of input ports, and a controller to provide control signals to control one or more of the variable gain controllers.

Abstract: In one aspect of the invention, text data recorded on a CD conforming to the CD-TEXT format is displayed using a minimum amount of memory. Storage capacity to be used per data item is calculated by dividing the available storage capacity by the number of text data items to be displayed on a display section, and the text data is read from the CD and is stored in a memory by limiting the storage capacity per data item to the thus calculated storage capacity. Priority may be given to a specific data item for which full data is acquired, and the remaining capacity may be equally divided among the other data items. In another aspect of the invention, text data recorded in a plurality of different languages on a CD conforming to the CD-TEXT format is acquired in as many languages as possible by using a minimum amount of memory.

Abstract: A method for determining an end of a first period in which signals are communicated in a first direction is provided. The method comprises sampling a signal for a period of time up to at least as long as the longest expected length of the first period to obtain a sampled signal. The sampled signal is integrated to obtain an integrated power curve. A reference line is subtracted from the integrated power curve to obtain a rotated power curve. A peak in the rotated power curve is selected as an end of the first period.

Abstract: An apparatus and method for sensing hazardous materials utilizes first and second optical fibers and a recirculator coupled to a substrate. The first optical fiber is coupled to the substrate and has first and second opposing ends and a first substance embedded therein. The first substance is reactive to a first hazardous material type. The second optical fiber is coupled to the substrate and has first and second opposing ends and a second substance embedded therein. The second substance is reactive to a second hazardous material type. The at least one recirculator is coupled to the substrate and configured such that when light propagates from one of the ends of at least one of the first and second optical fibers, at least some of the light is directed by the at least one recirculator into the opposing end of the respective optical fiber.

Abstract: A computer-implemented method is provided to facilitate creation of linked inter-related models in a database. The method comprises obtaining a search text and match criteria from a user, and determining whether a prequery exists. If not, a list of all destination items is obtained. If yes, a determination is made whether the prequery is enabled. If not, a list of all destination items is obtained. If enabled, a list of all destination items limited by the prequery is obtained. A determination is then made whether all match criteria is selected. If yes, all items in the destination list are returned to the user. If not, a word list is generated by parsing all words from the search text. All valid synonyms are added for each word in the word list. The items in the destination list are reduced to items that match at least one word in the word list. A determination is made whether one or more additional filters exist. If not, a reduced list filtered by the match criteria is returned to the user.

Abstract: Systems and methods for orthogonal frequency division multiplexing are provided. In one embodiment, a multi-carrier modem comprising: a receiver configured to de-modulate symbols from at least one of a plurality of spectrally overlapping carrier signals; a transmitter configured to modulate symbols onto at least one of a plurality of the spectrally overlapping carrier signals; a processor coupled to the transmitter, wherein the processor outputs data for transmission by the transmitter, wherein the processor applies an inverse Fourier transform to the data transmitted by the transmitter; and a controller programmed to instruct the transmitter to transmit a coarse timing adjustment followed by at least one secondary timing adjustment, wherein the secondary timing adjustment is a fine tuning adjustment with respect to the coarse timing adjustment.

Abstract: A method of determining ranges for algorithmic variables for a processor that uses fixed point arithmetic is provided. The method comprises expressing overflow requirements of processor instructions as inequalities. The method also expresses precision requirements and expressiveness requirements as inequalities and merit functions. A global constraint and optimizer tool is used to find ranges for algorithmic variables based on the inequalities and the merit functions. The use of constraint equation solving and optimization finds optimal algorithmic ranges that provide overflow-free arithmetic as well as optimal expressiveness and precision.