Keysight (Agilent) U9391M Comb Generator, 10 MHz to 110 GHz

The Keysight U9391M Comb Generator is a precision phase reference standard operating from 10 MHz to 110 GHz, engineered for frequency metrology and calibration of microwave and millimeter-wave components and systems. It delivers NIST-referenced phase calibration for non-linear measurements in conjunction with the Keysight PNA-X nonlinear vector network analyzer, offering excellent phase and amplitude flatness across its output range. The instrument accepts input signals from 10 MHz to 6 GHz and provides user-selectable frequency divider ratios of 1, 2, 4, 8, 16, 32, 64, or 128, with a minimum tone spacing of 10 MHz.

Its architecture exhibits low sensitivity to input power and fundamental frequency variations, enabling single-condition calibration to extend across a wide range of input powers and operating frequencies. Embedded calibration data is stored onboard and retrieved via USB interface for rapid access.

Technical Specifications

• Output Frequency Range: 10 MHz to 110 GHz


• Input Frequency Range: 10 MHz to 6 GHz


• Frequency Divider Ratios: 1, 2, 4, 8, 16, 32, 64, 128 (user-selectable)


• Minimum Tone Spacing: 10 MHz


• Phase Reference: NIST-referenced calibration with precision phase and amplitude flatness


• Operating Temperature: 0 to 40 °C


• Storage Temperature: −40 to 70 °C


• Power: USB 3.0 connection (control, data, and power delivery)

Key Features

• Low input power and frequency sensitivity for broad calibration applicability


• Rugged connectors with high repeatability across multiple connects and disconnects


• USB 3.0 plug-and-play integration with PNA-X NVNA systems


• Fast embedded calibration data retrieval via USB interface


• Extended operating life design

Typical Applications

• Frequency metrology


• Calibration of microwave and millimeter-wave components and systems


• Non-linear device characterization and phase calibration

Compatibility & Integration The U9391M is specifically designed for the Keysight PNA-X nonlinear vector network analyzer. Optimal performance requires compatible PNA-X firmware revisions. The instrument is compatible with broadband mmWave (M4) solutions but not with banded configurations.