The Advantest U3851 is a cross-domain analyzer that integrates network analysis, spectrum analysis, and impedance analysis within a single instrument spanning 9 kHz to 8 GHz. It performs simultaneous two-channel measurement and analysis across time, amplitude, phase, and frequency domains—a capability enabling direct signal comparison and characterization of components and circuits. The instrument features industry-first two-channel phase synchronization for vector signal analysis, making it suited for R&D and manufacturing environments in telecommunications and broadcasting.
Technical Specifications
Frequency Coverage: 9 kHz to 8 GHz
Time-Domain Analysis
• Maximum analysis bandwidth: 40 MHz
• Time resolution: 15.4 ns (at 40 MHz CBW) to 2 ms (at 100 Hz CBW)
• Supports Frequency vs. Time, Power vs. Time, and Phase vs. Time analysis
• Wide-band time-domain analysis available
Capture Bandwidth: 100 Hz to 30 MHz (1-3 steps); extends to 40 MHz
Sampling Rate: 500 Hz (at 100 Hz CBW) to 65 MHz (at 40 MHz CBW) for I/Q pair data per sample
Inter-Channel Balance (at 1 GHz, CBW 100 kHz/ms, −30 dBm input)
• Amplitude: ±2.0 dB
• Phase: ±15 deg
RF Input (L-input)
• Connector: N-type female, 50 Ω nominal impedance
• VSWR: <1.7:1 (10 MHz to 3.0 GHz); 3.0 GHz)
• Maximum safe input: +30 dBm (Pre-Amp OFF, ≥10 dB attenuator); +13 dBm (Pre-Amp ON, 0 dB attenuator)
• DC rating: ±15 VDC max
RF Input (H-input)
• Maximum safe input: +10 dBm (0 dB attenuator)
• DC rating: ±25 VDC max
Calibration Signal Output
• N-type female connector, 50 Ω impedance
• 20 MHz reference frequency
– Key Features
• Two-channel phase-synchronized vector signal analysis
• Vector math operations (composition and decomposition via X function)
• High-purity spectrum analysis option for enhanced phase noise measurement
• FFT analysis capability
• Built-in pre-amplifier for high sensitivity and antenna loss compensation
– Typical Applications
Component and circuit characterization; phase noise measurements; multi-channel signal correlation in telecommunications and broadcast systems; time-domain and frequency-domain signal decomposition.
– Compatibility & Integration
Standard 50 Ω RF interface. Dual N-type connectors support independent measurement channels with synchronized timing and phase reference.
