Abstract: A magnetic resonance detection (MRD) system for and methods of detecting and classifying multiple chemical substances is disclosed. In one example, the presently disclosed MRD system is a nuclear quadrupole resonance (NQR) detection system that provides multi-frequency operation for substantially full coverage of the explosive NQR spectrum using a broadband transmit/receive (T/R) switch (or duplexer) and a single multi-frequency radio frequency (RF) transducer. More particularly, the MRD system provides a frequency-agile system that can operate over a wide band of frequencies or wavelengths. Further, a method of detecting and classifying various chemical substances is provided that includes pulse sequencing with “frequency hopping,” phase cycling for reducing or substantially eliminating background noise, and/or a process of mitigating amplitude modulation (AM) radio interference.

Abstract: A signal processing system includes a random decision forests-based bulk filter. The signal processing system further includes one or more sensors (e.g., radar systems, satellite systems) that interface with the signal processing system via a radio frequency (RF), electro-optical (EO) or infrared (IR) exchange process, a computationally inexpensive object detector, a computationally inexpensive state estimator, then the random decision forests-based bulk filter, a computationally expensive object tracker, a computationally expensive object discriminator, and a report. Further, the random decision forests-based bulk filter features a filter training optimization process.

Abstract: An example firearm with a short overall length and improved storage compactness comprises a forward takedown subassembly comprising a barrel, a trigger control mechanism configured to provide an electrical trigger control signal, and a signal transmitter electrically coupled to the trigger control mechanism, and further comprises a rearward takedown subassembly separable from the forward takedown subassembly and comprising a stock, a receiver comprising an electrically controlled firing mechanism, and a signal receiver electrically coupled to the firing mechanism. A takedown mechanism has first and second portions fixedly coupled to the forward takedown subassembly and the rearward takedown subassembly, respectively, and is configured to repeatably couple the forward takedown subassembly to the rearward takedown subassembly.

Abstract: A spatial modulator for RF beams (microwave (uW), millimeter wave (MMW), and sub-millimeter wave (sub-MMW)) using dynamically-writable highly-reflective regions, with sub-wavelength diffractive pattern spatial definition that is finer than the wavelength of the incident RF beam.

Abstract: An apparatus and method of recoil mitigation for a gun mounted on a lightweight platform is disclosed.

Abstract: A photonic implementation of the modulated wideband converter (MWC) is described. The highly scalable compressive sensing receiver architecture uses photonic components for analog front-end compression and downconversion, allowing scalable data conversion over an extremely wide instantaneous surveillance bandwidth, limited only by the peak anticipated signal occupancy and application-dependent size, weight, and power constraints.

Abstract: A method and apparatus for firing a plurality of disrupter loads in arbitrary order at the discretion of the user is disclosed. The loads may be of the same or different types. Both liquid and solid projectiles may be fired. Further, the disrupter may be operated by a user at safe standoff distance from a robotic mount with the aid of control, targeting, ranging and recoil systems.

Abstract: A photonic implementation of the modulated wideband converter (MWC) is described. The highly scalable compressive sensing receiver architecture uses photonic components for analog front-end compression and downconversion, allowing scalable data conversion over an extremely wide instantaneous surveillance bandwidth, limited only by the peak anticipated signal occupancy and application-dependent size, weight, and power constraints.

Abstract: Methods and apparatus for detecting the presence of electronic communications devices, such as cellular phones, are disclosed. In an exemplary method, a complex radio frequency stimulus is transmitted into a target area, and nonlinear reflection signals received from the target area are processed to obtain a response measurement. The response measurement is compared to a pre-determined filter response profile to detect the presence of a radio device having a corresponding filter response characteristic. In some embodiments, the pre-determined filter response profile comprises a pre-determined band-edge profile, so that comparing the response measurement to a pre-determined filter response profile comprises comparing the response measurement to the pre-determined band-edge profile to detect the presence of a radio device having a corresponding band-edge characteristic.