Keysight (Agilent) N9321C Basic Spectrum Analyzer (BSA)

The Keysight (Agilent) N9321C Basic Spectrum Analyzer is a cost-effective RF measurement instrument covering 9 kHz to 4 GHz, engineered for education, manufacturing, field service, and general laboratory RF analysis. It delivers essential spectrum measurement capabilities with typical displayed average noise level of -152 dBm at 1 GHz and amplitude accuracy of ±0.3 dB, making it suitable for wireless communication diagnostics, EMI troubleshooting, and RF design verification.

Technical Specifications

• Frequency Range: 9 kHz to 4 GHz


• Frequency Span: 0 Hz to 4 GHz with 1 Hz resolution


• Frequency Span Resolution: 1 Hz


• Frequency Readout Accuracy: ± (frequency indication × frequency reference uncertainty + 1% × span + 20% × resolution bandwidth + marker resolution + 1 Hz)


• Frequency Reference Aging Rate: ±1 × 10⁻⁷/Year (with optional PFR)


• Frequency Reference Temperature Stability: ±1.5 × 10⁻⁸ from 20 °C to 30 °C (with optional PFR)


• Displayed Average Noise Level: -152 dBm typical at 1 GHz


• DANL Noise Floor: -162 dBm/Hz at 1 GHz


• Absolute Amplitude Accuracy: ±0.3 dB typical; ±0.6 dB overall


• Third-Order Intercept (TOI): +15 dBm at 1 GHz


• Phase Noise: -90 dBc/Hz at 1 GHz (10 kHz offset)


• Resolution Bandwidth: 10 Hz to 3 MHz with RBW/Span ratio ≥ 0.02


• Attenuator Step: 1 dB


• Minimum Sweep Time: 2 ms (non-zero span)


• Analysis Bandwidth (Maximum): 1 MHz

Key Features

• Spectrum analyzer mode as standard configuration


• Optional tracking generator for transmission and scalar network measurements


• Optional reflection measurement capability and Distance-to-Fault analysis


• AM/FM modulation analysis with optional Modulation Analysis Module (AMA)


• ASK/FSK digital modulation decoding (Option DMA)


• Channel power, occupied bandwidth (OBW), and adjacent channel power (ACPR) measurements


• Spectrum emission mask (SEM) analysis


• Spectrum monitoring for interference detection


• Power meter mode integration with Keysight U2000 Series and U2020 X-Series USB sensors


• Optional Precision Frequency Reference (PFR) for ±0.1 ppm annual aging

Typical Applications Wireless communication system design and validation, RF component testing, EMI/RFI diagnostics, transmitter verification, cable and connector assessment, signal integrity analysis, educational RF laboratories.

Compatibility & Integration Supports Keysight U2000 Series and U2020 X-Series USB power sensors for extended measurement capability.