Voltage Controlled Oscillator (VCO): An oscillator whose output frequency is directly determined by a voltage applied at the tuning port.

Resonator: Abracon designs utilize one of three various design topologies to achieve optimum VCO performance: LC (inductor-capacitor), microstrip, or CRO (coaxial resonator. The type of resonating structure utilized is typically based on operating frequency, bandwidth, phase noise, and size constraints of the VCO.

Frequency Bandwidth: The total frequency a VCO will cover given the tuning voltage range.

Tuning Sensitivity: the slope or rate the frequency changes per tuning voltage change expressed in MHz/V.

Phase Noise: the ratio of the 1 Hz bandwidth single side band noise measured between the carrier frequencies power and an offset frequency. Value reported in dBc/Hz. See figure 1.

Power Output: the total output energy from the oscillator measured into a 50 ohm load. The signal strength value is given as decibels relative to one milliwatt or dBm.

Harmonics: the component frequency of a signal that are integer multiples of the fundamental frequency. It is expressed in dBc or harmonic strength in relationship to the fundamental. See figure 2.

Sub-Harmonics: spurious non-integer signals generated from the fundamental frequency expressed in dBc.

Pushing: a frequency output change caused by a change in the supply voltage while keeping a constant tuning voltage. Value expressed in MHz/V.

Pulling : a frequency shift due to a change in the output load. Specified as load return loss of 12 dB and all phases.

Phase Lock Loop (PLL): a feedback loop which maintains a locked condition between the VCO and a reference signal. See figure 3.

Phase Detector: compares the frequency and phase of two signals and generates a current that is a function of the difference between the signals.