Keysight (Agilent) N5500A Phase Noise Test Set

The Keysight (Agilent) N5500A Phase Noise Test Set is a specialized instrument for characterizing phase noise in RF and microwave components. It operates as a core module within the E5505A Phase Noise Measurement System, delivering phase noise measurements across carrier frequencies from 50 kHz to 1.6 GHz in standard configuration, with optional extensions to 26.5 GHz. The instrument measures offset frequencies from 0.01 Hz to 100 MHz (or 0.01 Hz to 2 MHz without a swept analyzer), providing the sensitivity and frequency resolution required for both development and production testing.

Technical Specifications

• Standard: 50 kHz to 1.6 GHz


• With Option 201 or Option 001: Extended to 26.5 GHz Offset Frequency Range:


• 0.01 Hz to 100 MHz (with optional signal/spectrum analyzers)


• 0.01 Hz to 2 MHz (without swept analyzer) Signal Input Power Levels:


• SIGNAL Input (Standard): 0 to +23 dBm


• REF INPUT (Standard): +15 to +23 dBm


• μW SIGNAL Input (Option 201): 0 to +5 dBm; REF INPUT +7 to +10 dBm


• Input Power (Option 001): 0 to 30 dBm NOISE Input:


• Frequency Range: 0.01 Hz to 100 MHz


• Input Impedance: 50 ohms


• Maximum Amplitude: 1 Volt peak Output Filters:


• Low-pass filters: 100 MHz, 20 MHz, 2 MHz, 200 kHz, 20 kHz


• Decade-spaced filters (high-pass and low-pass): 1 Hz to 100 kHz

Key Features

• Dual measurement paths: internal phase detectors for standard RF signals or external NOISE input for millimeter-wave, AM noise, and baseband measurements


• Multiple analyzer outputs: FFT analyzer outputs (<100 kHz), spectrum analyzer outputs (<100 MHz), and RF analyzer for signals to 26.5 GHz


• Time-domain and frequency-domain observation via MONITOR and TUNE VOLTAGE outputs


• Selectable low-pass and high-pass filter configurations for bandwidth control

Typical Applications

• Phase noise characterization of oscillators, amplifiers, and frequency sources


• Millimeter-wave measurements with external mixers


• AM noise evaluation with external detectors


• VCO tuning and closed-loop phase-locked measurements

Compatibility & Integration Integrates with baseband analyzers and dedicated software via GPIB remote control. Accepts signal inputs from external noise sources and detectors, enabling flexible measurement architectures.