Abstract: A chirped radio frequency signal is transmitted across an area of a potential threat. A reflected radio frequency return signal from an open barrel of a weapon at a location within the area of the potential threat is received at an incident angle through an aperture. An antenna at a position in an antenna array detects the reflected radio frequency return signal received at the incident angle through the aperture. The position of the antenna within the antenna array corresponds to a direction from which the reflected radio frequency return signal originates.

Abstract: A high pass filter includes: an input-impedance-matching taper transition metal layer having an IMT input end and an IMT output end, the IMT input end having an IMT input end width, the IMT output end having an IMT output end width that is wider than the IMT input end width; a substrate integrated waveguide having a SIW input end and a SIW output end; and an output-impedance-matching taper transition metal layer having an OMT input end and an OMT output end, the OMT input end having an OMT input end width, the OMT output end having an OMT output end width that is wider than the OMT input end width. The substrate integrated waveguide is arranged such that the IMT output end is electrically connected to the SIW input end and such that the OMT input end is electrically connected to the SIW output end.

Abstract: A device includes an enclosure cover; a chip carrier attachable to and removable from the enclosure cover; and a ridge gap waveguide (RGW) cover. The chip carrier includes at least two cavities disposed on one surface and located on opposite sides, and each cavity has a slot extending to an opposite surface of the chip carrier. The RGW cover includes a plurality of ridges and a plurality of pillars disposed on one surface. The enclosure cover and the RGW cover are configured to connect to each other with the chip carrier located therebetween, and the opposite surface of the chip carrier faces the one surface of the RGW cover when the enclosure cover and the RGW cover are connected.

Abstract: A device includes an enclosure cover having a groove portion disposed on one surface, a chip carrier attachable to and removable from the enclosure cover in the groove portion, the chip carrier including at least two cavities disposed on one surface and located on opposite sides, each cavity has a slot extending to an opposite surface of the chip carrier. Also included is a ridge gap waveguide (RGW) cover with a plurality of pillars disposed on one surface, and a plurality of ridges are also disposed on the one surface. Each ridge includes a branching junction such that each ridge branches to at least two ridge portions. The enclosure cover and the RGW cover are configured to connect to each other with the chip carrier located therebetween, and the opposite surface of the chip carrier faces the one surface of the RGW cover.

Abstract: A chirped radio frequency signal is transmitted across an area of a potential threat. A reflected radio frequency return signal from an open barrel of a weapon at a location within the area of the potential threat is received at an incident angle through an aperture. An antenna at a position in an antenna array detects the reflected radio frequency return signal received at the incident angle through the aperture. The position of the antenna within the antenna array corresponds to a direction from which the reflected radio frequency return signal originates.

Abstract: A tunable notch filter comprising a transmission line, a tunable bandstop filter and a tunable bandpass filter. The transmission line has an input port, an output port and a length electrically connecting the input port to the output port and receiving an RF signal at the input port. The tunable bandstop filter comprises a first direct current voltage source, a first coupling line and a first tunable capacitor. The first direct current voltage source provides a first adjustable voltage to the first tunable capacitor. The first tunable capacitor adjusts its capacitance based on the first adjustable voltage. The tunable bandpass filter comprises a second direct current voltage source, a second coupling line and a second tunable capacitor. The second direct current voltage source provides a second adjustable voltage to second tunable capacitor. The second tunable capacitor adjusts its capacitance based on the second adjustable voltage.

Abstract: A tunable notch filter comprising a transmission line, a tunable bandstop filter and a tunable bandpass filter. The transmission line has an input port, an output port and a length electrically connecting the input port to the output port and receiving an RF signal at the input port. The tunable bandstop filter comprises a first direct current voltage source, a first coupling line and a first tunable capacitor. The first direct current voltage source provides a first adjustable voltage to the first tunable capacitor. The first tunable capacitor adjusts its capacitance based on the first adjustable voltage. The tunable bandpass filter comprises a second direct current voltage source, a second coupling line and a second tunable capacitor. The second direct current voltage source provides a second adjustable voltage to second tunable capacitor. The second tunable capacitor adjusts its capacitance based on the second adjustable voltage.

Abstract: A system includes an RF input coupled to a plurality of channel filters through an inductive manifold. Each of the channel filters is configured as a series resonator and has a frequency of greater than about 1 GHz. The frequency of the channel filters decreases as their distance from the RF input increases. Components of each of the channel filters, which may include a series inductor, series capacitor, and shunt capacitor, are configured using high-Q transmission lines. A tunable notch filter, such as an absorptive tunable band-stop filter, may be included within the channel filters. The system may be used for protection of wideband receivers.

Abstract: A bandstop filter includes a coupled line bandstop filter, a capacitor and a resistor. The coupled line bandstop filter includes a transmission line element and a shaped transmission line element. The shaped transmission line element includes a coupled line element disposed so as to electromagnetically couple with the transmission line element, and a second line element disposed so as not to be parallel with the transmission line element. The capacitor is electrically connected to the coupled line element. A portion of the received oscillating signal includes a bandstop frequency. Physical attributes of the coupled line bandstop filter, the capacitor and the resistor are such that the portion of the received oscillating signal including the bandstop frequency is attenuated.

Abstract: A system includes a first low noise amplifier, a second low noise amplifier, a local oscillator, a signal splitter, a first mixer, a second mixer, an analog to digital converter, a digital channelizer and beam-former and a phase error correcting component. The phase error correcting component is configured to generate a first phase error correction coefficient and a second phase error correction coefficient. The digital channelizer and beam-former includes a polyphase filter and a time division multiplexer. The time division multiplexer is configured to output a beam-formed received signal based on a first modified filtered signal and the second modified filtered signal.

Abstract: A system includes an RF input coupled to a plurality of channel filters through an inductive manifold. Each of the channel filters is configured as a series resonator and has a frequency of greater than about 1 GHz. The frequency of the channel filters decreases as their distance from the RF input increases. Components of each of the channel filters, which may include a series inductor, series capacitor, and shunt capacitor, are configured using high-Q transmission lines. A tunable notch filter, such as an absorptive tunable band-stop filter, may be included within the channel filters. The system may be used for protection of wideband receivers.

Abstract: A bandstop filter is provided that includes an input port, a series bandpass resonator, a first capacitor, a bandstop resonator, a second capacitor and an output port. The combination of the first capacitor, the bandstop resonator and the second capacitor comprises a bandstop impedance magnitude and a bandstop impedance phase. The bandpass resonator impedance magnitude is substantially equal to the bandstop impedance magnitude. The bandpass resonator impedance phase is substantially 180° out of phase with the bandstop impedance phase. The series bandpass resonator, the first capacitor, the bandstop resonator and the second capacitor operate as a band stop for a predetermined frequency within the frequency band.

Abstract: A coaxial to waveguide transition includes a first rigid portion comprising an inverted hollow cone, a second rigid portion comprising a hollow tube, and a third rigid portion comprising a hollow cone. The first rigid portion has a first end and a second end, and tapers inward at a first angle from its first end towards its second end. The second rigid portion has a first end and a second end, with the first end being partially disposed within the second end of the first rigid portion. The third rigid portion has a first end and a second end, with the first end of the third rigid portion being partially disposed within the second end of the second rigid portion. The third rigid portion tapers outward at a second angle from its first end towards its second end, where the second angle is less than the first angle.

Abstract: A bandstop filter includes a coupled line bandstop filter, a capacitor and a resistor. The coupled line bandstop filter includes a transmission line element and a shaped transmission line element. The shaped transmission line element includes a coupled line element disposed so as to electromagnetically couple with the transmission line element, and a second line element disposed so as not to be parallel with the transmission line element. The capacitor is electrically connected to the coupled line element. A portion of the received oscillating signal includes a bandstop frequency. Physical attributes of the coupled line bandstop filter, the capacitor and the resistor are such that the portion of the received oscillating signal including the bandstop frequency is attenuated.

Abstract: A system is provided for combining multiple solid-state amplifiers using a radial combiner/divider. The system includes a coaxial input port, a coaxial output port, a first plurality of N waveguides radially disposed around a first transition, a second plurality of N waveguides radially disposed around a second transition, and a plurality of N amplifiers. A first end of each of the first plurality of waveguides is operatively connected to the coaxial input port via the first transition. A first end of each of the second plurality of waveguides is operatively connected to the coaxial output port via the second transition. A first port of each of the plurality of amplifiers is connected to a second end of one of the first plurality of waveguides and a second port of each of the plurality of amplifiers is connected to a second end of one of the second plurality of waveguides.

Abstract: A coaxial to waveguide transition includes a first rigid portion comprising an inverted hollow cone, a second rigid portion comprising a hollow tube, and a third rigid portion comprising a hollow cone. The first rigid portion has a first end and a second end, and tapers inward at a first angle from its first end towards its second end. The second rigid portion has a first end and a second end, with the first end being partially disposed within the second end of the first rigid portion. The third rigid portion has a first end and a second end, with the first end of the third rigid portion being partially disposed within the second end of the second rigid portion. The third rigid portion tapers outward at a second angle from its first end towards its second end, where the second angle is less than the first angle.

Abstract: A system is provided for combining multiple solid-state amplifiers using a radial combiner/divider. The system includes a coaxial input port, a coaxial output port, a first plurality of N waveguides radially disposed around a first transition, a second plurality of N waveguides radially disposed around a second transition, and a plurality of N amplifiers. A first end of each of the first plurality of waveguides is operatively connected to the coaxial input port via the first transition. A first end of each of the second plurality of waveguides is operatively connected to the coaxial output port via the second transition. A first port of each of the plurality of amplifiers is connected to a second end of one of the first plurality of waveguides and a second port of each of the plurality of amplifiers is connected to a second end of one of the second plurality of waveguides.