Abstract: A voltage controlled oscillator including an RF output terminal and a DC control terminal, an active circuit, and a resonant circuit interconnected with the active circuit and including a plurality of series resonators each having an electrically variable capacitance and fixed inductor; the active circuit includes at least one transistor having an operating current density which is approximately 35% or less of the peak fT operating current density and/or the active circuit includes a multi-transistor bank disposed in at least two separate sections, each pair of sections spaced apart to provide improved thermal uniformity among the transistors without substantially increasing parasitic impedance among them for providing an improved lower phase noise output at said RF output terminal.

Abstract: A phase shifter includes a low-pass filter, a high-pass filter, and an all-pass filter coupled in series between an RF input terminal and an RF output terminal of the phase shifter, at least one of the filters being tunable, controlling the phase of an input signal over a wide range of frequencies.

Abstract: An injection locked pulsed oscillator includes a voltage controlled oscillator (VCO) responsive to an injection signal. The injection locked pulsed oscillator includes at least one enable circuit responsive to a first enable signal to enable output pulses from the VCO. The injection locked pulsed oscillator also includes timing circuit responsive to a pulse repetition frequency signal and is configured to provide the injection signal to phase lock the VCO and provide the first enable signal delayed from the injection signal to shape a width of the output pulses from the VCO.

Abstract: This invention features an absorptive tunable bandstop filter with wide tuning range including first and second branches of all-pass filter networks, an input power divider for splitting the input signal and passing approximately half of the input signal power through each said branch of said all-pass filter networks, and an output power divider for recombining the signal power from each said branch of said all-pass filter networks, at least one of said branches of said all-pass filter networks being electrically tunable to provide an approximately 180° phase difference with similar amplitudes of the split said signal power to be recombined at said output power divider for rejecting but substantially absorbing selected frequencies.

Abstract: A phase shifter includes a low-pass filter, a high-pass filter, and an all-pass filter coupled in series between an RF input terminal and an RF output terminal of the phase shifter, at least one of the filters being tunable, controlling the phase of an input signal over a wide range of frequencies.