Keysight (Agilent) N4373E

The Keysight N4373E is a Lightwave Component Analyzer (LCA) that characterizes electro-optical components across modulation bandwidths of 43.5 GHz, 50 GHz, and 67 GHz. Operating from 10 MHz to 67 GHz, it delivers traceable S-parameter measurements with absolute frequency response accuracy better than 0.9 dBe at 50 GHz and 1.3 dBe at 67 GHz. The system supports single-mode fiber (1290 nm to 1620 nm at up to 67 GHz) and multimode fiber (850 nm at up to 50 GHz), with external wavelength capability via auxiliary laser input between 1290 nm and 1610 nm. Built on the N52xxB PNA Microwave Network Analyzer platform, it provides noise floors of <-59 dB (W/A) for E/O and <-55 dB (A/W) for O/E measurements at 67 GHz.

– Technical Specifications

• Frequency Range: 10 MHz to 67 GHz
• Modulation Bandwidth Options: 43.5 GHz, 50 GHz, 67 GHz
• Single-mode Fiber: 1290 nm to 1620 nm (up to 67 GHz)
• Multimode Fiber: 850 nm (up to 50 GHz, IEEE 802.3ae-2002 compliant)
• External Laser Input: 1290 nm to 1610 nm
• Transmitter Wavelengths: 850 nm, 1310 nm, 1550 nm
• Absolute Frequency Response Accuracy: <0.9 dBe @ 50 GHz; <1.3 dBe @ 67 GHz
• Relative Uncertainty: ±0.8 dBe @ 50 GHz; ±1.3 dBe @ 65 GHz
• Relative Frequency Response Accuracy: <0.5 dBe @ 50 GHz; <1.3 dBe @ 67 GHz
• E/O Noise Floor: <-59 dB (W/A) @ 67 GHz
• O/E Noise Floor: <-55 dB (A/W) @ 67 GHz

– Key Features

• Turn-key integrated solution for electro-optical S-parameter measurements
• Automated calibration using N4694A electronic calibration kit
• Built-in average power meter for transmitter verification
• User-selectable transmitter output power
• Temperature-stabilized transmitter and receiver
• Common PNA and LCA user interface across N437xx series
• Measures electro-optical transfer function, responsivity, 3 dB cutoff frequency, bandwidth, insertion loss/gain, impedance match, and group delay

– Typical Applications

• 40G/100GbE component development and validation
• 400 Gbps and 1 Tbps transmission systems
• Radio over Fiber (RoF) applications
• Aerospace and defense electro-optical testing

– Compatibility & Integration

The N4373E leverages the N52xxB PNA Microwave Network Analyzer series and maintains interface consistency with the N437xx LCA product line, enabling seamless integration into existing Keysight network analyzer environments.