• 5 MHz to 18 GHz
• Phase noise and AM noise measurements
• Low system noise floor

The HP 11729B, combined with an HP 8662A synthesized signal generator and a baseband spectrum analyzer, form a complete broadband measurement system for phase noise and AM noise testing of microwave oscillators, 5 MHz to 18 GHz. With one versatile measurement system, direct AM noise measurements and two methods of phase noise measurements can be made, at offsets from the carrier of < 1 Hz to 10 MHz. These three operating modes allow a wide variety of sources, from low noise stabilized sources to free-running sources with high drift to be measured. The HP 11729B may be ordered with either full frequency coverage, or in a number of band configurations to better match the application.

Built-In Low Noise Reference

The HP 11729B/8662A combination includes the critical low noise microwave reference signal (which determines the system noise floor). The wide frequency range and low system noise floor of the HP 11729B/8662A enable a signal system to be used on a broad range of sources. Typical system noise for a 10 GHz source is less then -123 dBc/Hz at a 10 kHz offset, allowing characterization of most high-performance sources.

Two Phase Noise Measurement Modes

A choice of two phase noise measurement methods optimizes the measurement to the type of oscillator being measured. The phase detector method is ideal for synthesizers or stable free-running sources. The HP 11729B/8662A simplifies the phase detector method by providing all the necessary circuitry, including the low noise microwave reference source, the loop VCO, and a variable bandwidth phase-lock-loop.

The frequency discriminator method is best suited for sources with high level, low-rate phase noise such as free-running sources. The HP 11729B/8662A implements a convenient frequency discriminator (delay line/mixer technique), allowing sources to 18 GHz to be tested with a discriminator operating at an IF frequency less than 1.3 GHz. The HP 11729B/8662A contain all necessary hardware, except a simple user-supplied delay element that can be as simple as a length of inexpensive 50-ohm coaxial cable.

Direct AM Noise Measurements

The HP 11729B Option 130 offers convenient, direct AM noise measurements with typical sensitivity of less than -165 dBc/Hz. The HP 8662A provides a convenient calibration signal, and the same baseband analyzer used for phase noise measurements can be used for AM noise measurements.

Fully Programmable For System Integration

The fully HP-IB programmable HP 11729B/8662A is easily configured into manual or automatic carrier noise measurement systems with available spectrum analyzers (such as the HP 8566B, 8568B, 3561A, 3585A, or 3582A). In addition, the HP 11729B/8662A is an integral part of the HP 11740S automatic phase noise measurement system. The choice of analyzer determines the offset frequencies that can be measured. System noise floor is set by the HP 11729B/8662A.