Agilent/Keysight 3709B

The Agilent/Keysight 3709B is a Constellation Analyzer for digital radio demodulator characterization and network traffic analysis. It connects directly to I, Q, and Symbol Clock test points on radio demodulators to measure modulation quality and decode traffic across ATM, Frame Relay, and LAN networks. The instrument provides real-time hardware filtering, IP-level traffic isolation, and detailed post-capture analysis for protocol troubleshooting.

– Technical Specifications

Modulation Analysis
• Supported formats: QPSK, 16-QAM, 64-QAM, 256-QAM, 9-QPR, 25-QPR, 49-QPR, 81-QPR
• Constellation display for visual modulation quality assessment
• I/Q and Symbol Clock test point connections to radio demodulator

Data Filtering & Capture
• Hardware-based pre-capture filtering to maximize buffer allocation
• IP source and destination address filtering
• Event counting (cells, frames) within user-defined filter criteria
• Real-time application-level filtering on ATM and Frame Relay circuits

Traffic Analysis
• LAN traffic isolation on ATM or Frame Relay networks
• Frame Relay traffic isolation on ATM networks
• IP traffic encapsulated in Frame Relay over ATM
• Post-capture display filtering and search functionality

– Key Features

• Constellation display provides immediate visual feedback on demodulation performance
• Real-time hardware filtering enables targeted data collection without buffer waste
• IP-level filtering supports source and destination address-based traffic isolation
• Event counting across multiple frame/cell types within filter windows
• Agilent Advisor software for advanced analysis and troubleshooting workflows

– Typical Applications

• Radio modem demodulator verification and troubleshooting
• ATM/Frame Relay network protocol analysis
• LAN traffic characterization over WAN circuits
• IP traffic encapsulation layer analysis
• Digital modulation quality assessment

– Compatibility & Integration

The 3709B is legacy/obsolete per Keysight’s product line but remains supported. Drivers, firmware, and software are available through Keysight’s support portal.