The Advantest U3872 Cross Domain Analyzer integrates spectrum analysis, network analysis, and time-domain analysis across 9 kHz to 43 GHz in a single instrument. Dual-channel RF inputs enable simultaneous, synchronized measurement across time, amplitude, phase, and frequency domains for direct signal comparison. The unit captures I/Q waveforms with trigger and phase synchronization, supporting capture bandwidths from 100 Hz to 40 MHz and sampling rates up to 65 MHz. Time-domain capabilities include power-versus-time, frequency-versus-time, and phase-versus-time analysis with maximum 40 MHz analysis bandwidth. FFT analysis operates from 100 Hz to 40 MHz with accuracy better than ±1%. Spectrum analysis achieves -85 dBc/Hz purity at 10 kHz offset over spans ≤200 kHz. Inter-channel amplitude balance is ±2.0 dB and phase balance is ±15 degrees at 1 GHz under standard conditions. Optional tracking generators extend capabilities: OPT.76 covers 100 kHz to 3 GHz with ±300 Hz accuracy and -5 to -60 dBm output; OPT.77 spans 100 kHz to 6 GHz with -5 to -30 dBm output. Both options deliver ≤-80 dBm TG leakage at 0 dB input attenuation. A high-stability frequency reference (OPT.20) provides aging stability of ±2 × 10⁻⁸/day and temperature stability of ±5 × 10⁻⁸ across 0–40°C. EMC filtering option (OPT.28) includes 6 dB bandwidths at 200 Hz and 9 kHz.
Technical Specifications
• Frequency Range: 9 kHz to 43 GHz
• Capture Bandwidth: 100 Hz to 30 MHz (1–3 steps), 40 MHz
• Sampling Rate: 500 Hz to 65 MHz (varies with capture bandwidth)
• Time Resolution: 15.4 ns to 2 ms (capture bandwidth dependent)
• Waveform Recording Time: 120 ms to 1000 s (capture bandwidth dependent)
• Spectrum Purity: -85 dBc/Hz (10 kHz offset, span ≤200 kHz)
• FFT Accuracy: <±1% (100 Hz to 40 MHz)
• Inter-Channel Amplitude Balance: ±2.0 dB (1 GHz, after calibration)
• Inter-Channel Phase Balance: ±15 degrees (1 GHz, after calibration)
– Key Features
• I/Q waveform capture with trigger and phase synchronization
• Simultaneous power, frequency, and phase time-domain analysis
• Dual-channel RF input for comparative measurements
• Resolution bandwidth from 5 kHz to full frequency sweep
• Optional tracking generator to 3 GHz or 6 GHz
• High-stability reference source with ±2 × 10⁻⁸/day aging
– Tracking Generator Options
• OPT.76 (to 3 GHz): 100 kHz–3 GHz, ±300 Hz accuracy, -5 to -60 dBm output
• OPT.77 (to 6 GHz): 100 kHz–6 GHz, -5 to -30 dBm output
– Typical Applications
Wireless communications testing, aerospace and defense signal characterization, network analysis, and research and development requiring cross-domain signal validation.


















