The HSM18001B RF synthesizer module is a broadband signal source (10 MHz to 20 GHz, 0.001 Hz minimum step size) providing excellent spectral purity from sub-VHF through Ku-Band. Typical phase noise at 18 GHz is -106 dBc/Hz at 10 kHz offset. The HSM18001B has an adjustable output power dynamic range covering -20 to +20 dBm in 0.01 dB steps as well as an integrated pulse modulation function with rise and fall times as fast as 10 ns. While performance is crucial for many applications, reliability is extremely valuable if not critical for most. This compact, CW source has a field proven mean time between failures (MTBF) of greater than 240,000 hours, making it optimal for both commercial and defense applications.
The proprietary, non-PLL architecture of the HSM series RF synthesizer modules creates a phase coherent relationship between multiple channels (synthesizers) when synchronized to a common reference signal. Each HSM18001B module hosts an internal 100 MHz precision oven-controlled crystal oscillator (OCXO), which can be phase locked to an external 10 MHz reference signal or superseded by an external 100 MHz reference signal. Phase coherency is unique for this class of signal generator because each channel can be independently tuned for frequency, amplitude and phase offset while maintaining a phase coherent relationship.
Popular automatic test equipment (ATE) applications benefit from phase coherency, including intermodulation distortion and load-pull testing. Precision timing provided through phase coherent signals is advantageous for many other applications, from particle accelerator timing to SATCOM. The most apparent use of phase coherent signals in the defense market is for radar system local oscillators (LO).
The HSM18001B offers phase coherency coupled with compact size, high reliability, fast switching and excellent phase noise performance. Holzworth also offers the HSM12001B RF synthesizer module covering 10 MHz to 12.5 GHz (sub-VHF through X-Band), offering the same performance and features as the HSM18001B for applications not exceeding X-Band at a lower price point.