Abstract:
There is provided an exemplary tire pressure monitoring (TPM) system that can use a half-duplex wireless link to communicate between one or more wheel-mounted sensor units and a vehicle-mounted transceiver unit. The half-duplex wireless link enables the sensor units to report sensor readings to the transceiver unit, and it enables the transceiver unit to make configuration changes to the sensor units for improved communication. Some examples of wireless settings that can be modified include modulation settings, data encoding/decoding settings, error correction settings, and transmission power settings.
Abstract:
The radiation properties and wave guiding properties of frequency selective surfaces are used in conjunction with closely spaced antenna elements to fabricate antenna structures having adjustable radiation characteristics. The direction, magnitude, and polarization of radiation patterns for such antenna structures can be adjusted by varying the texture or patterning of layers of conducting material forming the frequency selective surfaces. The invention enables the fabrication of low profile antenna structures that can easily be conformed or integrated into complex surfaces without sacrificing antenna performance.
Abstract:
To facilitate GPS hardware selection and evaluate performance of vehicle integrated GPS hardware, including various types of GPS antennas and receivers, within different vehicle operating environments, embodiments of the invention are used to provide a simulator which does not require physical GPS hardware to simulate GPS system performance. Preferably, the simulator randomly generates one or more GPS system link budget variables, within predetermined performance bounds, in order to predict GPS system performance in a specific vehicle operating environment for a given antenna radiation pattern and/or GPS receiver. The simulator employs a Monte Carlo technique to evaluate the GPS system performance based on generated pools of link budget variables.
Abstract:
A collision avoidance system for reducing false alerts by estimating the elevation of a target, includes short and long range single-dimensional scanning radar sensors having differing ranges and beam angles of inclination, and a digital fusion processor, and preferably includes a locator device, an inclinometer, and a memory storage device cooperatively configured to further perform trend analysis, and target tracking.
Abstract:
The radiation properties and wave guiding properties of frequency selective surfaces are used in conjunction with closely spaced antenna elements to fabricate antenna structures having adjustable radiation characteristics. The direction, magnitude, and polarization of radiation patterns for such antenna structures can be adjusted by varying the texture or patterning of layers of conducting material forming the frequency selective surfaces. The invention enables the fabrication of low profile antenna structures that can easily be conformed or integrated into complex surfaces without sacrificing antenna performance.
Abstract:
The present invention provides an apparatus for and method of determining the nature of the wireless environment which is in use and dynamically selecting appropriate frequency channels for data transmissions which are more likely to accommodate sustained data transmission at high speeds.
Abstract:
The RF/microwave switch/modulator uses an optically controlled diode 20. The reactance of the diode may be varied by varying the illumination intensity. In this fashion, the photodiode in conjunction with an external circuit can switch or modulate a microwave signal by varying the reactance of the diode using a laser light source or the like. The bias voltage may be varied to electronically tune the diode so that the microwave frequency of operation can be electronically controlled.
Abstract:
A long-range optical fiber communication link overcoming certain constraints on signal transmission range imposed by fiber-induced loss is disclosed herein. A first embodiment of the communication link (10) of the present invention includes an optical fiber (16) having a first and a second end wherein the attenuation of optical energy passing therethrough at wavelengths included within a transmission window is substantially minimized. The inventive link (10) further includes a first arrangement (22) and (36) for launching a first optical carrier of a first wavelength onto the first end of the fiber (16). Provision is made within the launching arrangement (22) and (36) for impressing a first modulating signal spanning a first frequency spectrum upon the first carrier. The first embodiment also includes a second arrangement (26) and (37) for launching a second optical carrier of a second wavelength onto the second end of the fiber, wherein the second wavelength is included within the transmission window. The second launching arrangement (26) and (37) is further disposed to impress upon the second carrier a second modulating signal spanning a second frequency spectrum segregated from the first spectrum. A first receiver (64) of a first bandwidth encompassing the first frequency spectrum is coupled to the second end of the fiber (16). The first receiver (64) is operative to extract the first modulating signal from the first optical carrier. A second receiver (58) having a second bandwidth encompassing the second frequency spectrum is coupled to the first end of the fiber (16).
Abstract:
A low cost radar system that employs monopulse beamforming to detect objects in the road-way both in elevation and azimuth. In one non-limiting embodiment, a beamforming receiver architecture includes a first beamforming device and a plurality of antennas coupled to the first beamforming device, and a second beamforming device and a plurality of antennas coupled to the second beamforming device. The first and second beamforming devices are oriented 90° relative to each other so that the receive beams provided by the first beamforming device detect objects in azimuth and the receive beams provided by the second beamforming device detect objects in elevation. A first switch is provided to selectively couple the sum pattern signal from the first and second beamforming devices to one output line, and a second switch is provided to selectively couple the difference pattern signals from the first and second beamforming devices to another output line.
Abstract:
Apparatus for a micro-electro-mechanical switch that provides single pole, double throw switching action. The switch has two input lines and two output lines. The switch has a seesaw cantilever arm with contacts at each end that electrically connect the input lines with the output lines. The cantilever arm is latched into position by frictional forces between structures on the cantilever arm and structures on the substrate in which the cantilever arm is disposed. The state of the switch is changed by applying an electrostatic force at one end of the cantilever arm to overcome the mechanical force holding the other end of the cantilever arm in place.