Abstract: Coupling between non-adjacent resonators and wave propagation through the waveguide structure in distributed EM filters are reduced by forming one or more holes in one or more of the resonators (planar or folded) and by passing a conductive structure through each hole normal to the resonator. The conductive structures (vertical vias or horizontal strips) are preferably grounded, either by direct connection or capacitive coupling to one or more ground planes or by creation of a virtual ground. The holes are spaced apart from the edges of the resonator so as to minimize any interference with the current and fields concentrated at the edges of each resonator. These conductive structures narrow the effective cavity width “aeff” for the waveguide as a whole and between non-adjacent resonators without affecting the cavity width “a” between adjacent resonators.

Abstract: Provided is a non-federated multi-function exciter. The non-federated multi-function exciter includes a waveform generator subsystem operable to provide waveforms programmable in time, duration, slope and frequency. A transmission subsystem is coupled to the waveform generator, the transmission subsystem having a first upconverter and a second upconverter coupled to the first upconverter. A communication modulation subsystem is coupled to the second upconverter of the transmission subsystem. A reference clock subsystem coupled to the waveform generator subsystem, the transmit subsystem and the communication modulation subsystem. The non-federated multi-function exciter is operable to generate interleaved radar and communication signals.

Abstract: Coupling between non-adjacent resonators and wave propagation through the waveguide structure in distributed EM filters are reduced by forming one or more holes in one or more of the resonators (planar or folded) and by passing a conductive structure through each hole normal to the resonator. The conductive structures (vertical vias or horizontal strips) are preferably grounded, either by direct connection or capacitive coupling to one or more ground planes or by creation of a virtual ground. The holes are spaced apart from the edges of the resonator so as to minimize any interference with the current and fields concentrated at the edges of each resonator. These conductive structures narrow the effective cavity width “aeff” for the waveguide as a whole and between non-adjacent resonators without affecting the cavity width “a” between adjacent resonators.

Abstract: Provided is a non-federated multi-function exciter. The non-federated multi-function exciter includes a waveform generator subsystem operable to provide waveforms programmable in time, duration, slope and frequency. A transmission subsystem is coupled to the waveform generator, the transmission subsystem having a first upconverter and a second upconverter coupled to the first upconverter. A communication modulation subsystem is coupled to the second upconverter of the transmission subsystem. A reference clock subsystem coupled to the waveform generator subsystem, the transmit subsystem and the communication modulation subsystem. The non-federated multi-function exciter is operable to generate interleaved radar and communication signals.

Abstract: A low noise frequency synthesizer 10 that uses uses frequency dividers 13, 15, at least one of which(divider 15) is incrementable and decrementable in half integer steps, and analog gain compensation in a phase/frequency detector 14 to achieve lower noise, lower spurious levels and faster switching speed than traditional methods of frequency synthesis. The key features of the present invention are its half integer dividers 13, 15 and the ability to adjust the phase detector gain to compensate the loop for varying divide numbers. The synthesizer 10 comprises two dividers 13, 15 that provide two reference frequency signals that are a function of an input signal and an output signal of the synthesizer 10. A voltage controlled oscillator (VCO) 18 provides the output signal (f.sub.O) of the frequency synthesizer 10. A phase/frequency detector 14 compares the reference frequency signals and provides a phase error output signal that drives the VCO 18.