QuinStar Technology’s QPL series Phase Locked Sources are available over the frequency range of 6 to 150 GHz. They offer excellent performance in terms of phase noise, stability and power output. Sources with either internal crystal reference or with provision for external reference signal may be supplied. Internal references are typically between 5 MHz to 150 MHz. External reference frequency may be determined by the frequency of the phase-locked oscillator and phase noise specifications, or may be a customer-specified reference frequency depending on the application. The phase noise of these phase-locked sources at various offset values is established by a combination of reference oscillator phase noise, loop bandwidth and basic oscillator noise characteristics. Within the loop bandwidth, the phase noise is largely determined by the reference oscillator noise content. Outside the loop bandwidth, the phase noise is established by the oscillator’s free-running noise characteristics. Hence, the noise characteristics of series QPL may be tailored to meet specified requirements.
The architecture and implementation scheme of these phase-locked sources depend on their operating frequency, output power, phase noise requirements and other technical considerations. Sources could involve Dielectric Resonator Oscillators (DRO), Microwave Voltage Controlled Oscillators or Gunn Diode Oscillators and frequency multipliers, and power amplifiers as appropriate. Phase-locking technique that results in optimal performance is selected from among many available options for realizing the phase-lock loop. Lock status indicator or lock alarm is provided to indicate the locked condition of the oscillator. Frequency synthesizers and model with some frequency tuning capability are offered as custom products.
The degree of packaging of series QPL sources is determined by customer requirements. QuinStar can supply these sources with minimal packaging or mounted on a simple base plate to permit easy integration with a subsystem. Alternatively, products can be fully packaged in rugged enclosure for stand-alone use or instrumentation. A choice of power supplies is also offered to suit the application.