314 results about "Range gate" patented technology

Narrow virtual transmit pulses are synthesized by differencing long-duration, staggered pulse repetition interval (PRI) transmit pulses. PRI is staggered at an intermediate frequency IF. Echoes from virtual pulses form IF-modulated interference patterns with a reference wave. Samples of interference patterns are IF-filtered to produce high spatial resolution holographic data. PRI stagger can be very small, e.g., 1-ns, to produce a 1-ns virtual pulse from very long, staggered transmit pulses. Occupied Bandwidth (OBW) can be less than 10 MHz due to long RF pulses needed for holography, while spatial resolution can be very high, corresponding to ultra-wideband (UWB) operation, due to short virtual pulses. X-Y antenna scanning can produce range-gated surface holograms from quadrature data. Multiple range gates can produce stacked-in-range holograms. Motion and vibration can be detected by changes in interference patterns within a range-gated zone.

A system for landing or docking a mobile platform is enabled by a flash LADAR sensor having an adaptive controller with Automatic Gain Control (AGC). Range gating in the LADAR sensor penetrates through diffuse reflectors. The LADAR sensor adapted for landing / approach comprises a system controller, pulsed laser transmitter, transmit optics, receive optics, a focal plane array of detectors, a readout integrated circuit, camera support electronics and image processor, an image analysis and bias calculation processor, and a detector array bias control circuit. The system is capable of developing a complete 3-D scene from a single point of view.

A security system senses intrusions into a shipping container through the opening of doors, cutting an opening, or removing the doors from their hinges. Intrusion information is transmitted to a remote receiver without interrogation, thereby reducing power consumption. Sensing is accomplished by employing a range-gated micro-impulse radar (“RGR”) that generates microwave pulses that bounce around the interior of the container. The RGR includes a range gate that enables measuring reflected signals during the time gate period that is set for the time it takes a pulse to propagate a maximum distance within the container and reflect back. A direct current signal level is produced that represents the average reflected signal level within the container, and a Doppler shift measurement is made that represents motion inside the container. The signals are conveyed to the transmitter for conveyance to the remote receiver.

Methods and systems for neurostimulation and / or neurotelemetry of electrically-excitable biological tissue. Embodiments include implanting single or multiple semiconductor diodes and applying a high frequency electrical volume current. Neurostimulation embodiments include local rectification of the volume current by the diode, which can provide a pulsating electrical waveform capable of locally stimulating neural tissue, hi neurotelemetry embodiments, semiconductor diodes can be placed in contact with excitable tissue and a low level electrical carrier wave can be passed through the tissue and implanted diode whereby low level tissue bioelectric events intermodulate with the carrier wave and encode bioelectrical effects. Remote detection and amplitude demodulation of the volume-conducted carrier wave can allow recovery of the bioelectrical waveform and provide a neurotelemetry function, hi other embodiments, implanted diodes are placed in series with a pressure switch or piezoelectric material which enables their function only with the focal application of an acoustic pressure wave. This enables a selectivity amongst multiple diode channels by acoustic wave focusing or alternately by a process of range-gating of a surface applied electrical current to the arrival time of an acoustic wave at a particular device.

A unit is described that is configured to control detonation of a munition such that the munition is detonated at a desired altitude. The unit includes a radar transmitter, a radar receiver that includes a radar range gate, and a sequencer. The sequencer is configured to receive a detonation altitude and set the range gate based on the received detonation altitude. The unit is also configured to output a detonation signal when radar return pulses received by the receiver aligned with gate delay pulses from the range gate.

A remote sensor and associated data processor, performs concurrent analysis of backscattered signals from a multi-beam acoustic Doppler emitter / receiver positioned against the inside wall of a conveying pipe or channel. Range-gating of the return signals allows independent analysis of discrete volumes of backscattered signal data corresponding to the distribution, concentration and travel velocity of small individual volumes or bins of water and suspended solids. Velocity is derived from the measured Doppler frequency shift for each bin. Relative solids concentration is estimated as a function of the measured intensity of the backscattered signals. The intensity data are calibrated by inputting site-specific environmental information, such as temperature, salinity, acoustical system constant, backscattered signal interpretation ratio between concentration and particle size, and concurrently measured concentration values obtained from physical sample collection and previous laboratory analysis into the analytical computer program. The program uses iterative routines that adjust calibration parameters using data obtained from the previous measurement on an adjacent layer in a continuous self-correcting process. The apparatus and method provide both historical and real-time measurements of distribution, concentration and velocity of suspended solids in a flow of piped or channeled liquid.