摘要:
A sensitive photon detection system generates an electronic photon sensor signal as a K factor times a number N photons per unit time. The system is configured by combining a separate optical amplifier with a gain factor K1 with a photo detector with a gain factor K2 such that K may be realized as the product of K1 and K2. The values of K1 and K2 are chosen to meet a predetermined K while optimizing a signal quality of the photon sensor signal. The optical amplifier may be preceded by a photon gathering device and/or a light chopping device to further optimize system performance. Further, the photon sensor signal may be further processed analog circuitry or may be digitized and processed using digital signal processing to generate an enhanced photon sensor signal with enhanced signal quality by adding gain and/or bandwidth limiting.
摘要:
An acoustic data collection system that uses an antenna array aboard a powered unmanned and remotely controlled parafoil. The antenna array has multiple microphone elements, whose outputs are combined to provide directionality to the data acquisition.
摘要:
Methods and systems are described for efficiently detecting an object. The system includes at least one electrode for measuring a displacement current. The at least one electrode is coupled to a floating ground configuration provided by an op-amp, where the inverting node of the op-amp is coupled to electrode and the non-inverting node is coupled to a signal generator. The system may include a single capacitance sensor for detecting an object. Systems may include a plurality of capacitance sensors in an array configuration for detecting an object.
摘要:
A method of detecting and treating cancerous or cancer-supporting tissue by applying low-power density electromagnetic signals to the tissue, inducing acoustic signals from a portion of the tissue that exhibits an electrical conductivity gradient, receiving the thus-induced acoustic signals and from them identifying the location of the tissue portion, applying time-reversal to the thus received acoustic signals, accumulating the strength of the time-reversed acoustic signals, and then applying the thus strengthened acoustic signals to the identified tissue portion.
摘要:
Methods and systems for using ground penetrating radar (GPR) to obtain subsurface images. The depression angle, frequency, and polarization can all be adjusted for the soil conditions at hand. In particular, the depression angle is set at the “pseudo-Brewster angle” for improved ground penetration.