Advantest U3841 – Cross Domain Analyzer

The Advantest U3841 Cross Domain Analyzer integrates spectrum analysis, network analysis, and oscilloscope functionality into a single instrument for detailed signal characterization across frequency and time domains. Operating from 9 kHz to 3 GHz with maximum analysis bandwidth of 40 MHz, it delivers simultaneous IQ pair sampling at rates from 500 Hz to 65 MHz depending on capture bandwidth selection. The U3841 measures signals from displayed average noise level to +30 dBm with level accuracy of ±1.0 dB (9 kHz to 3 GHz) and ±0.8 dB (10 MHz to 3 GHz).

It accommodates ±50 VDC maximum input and features a pre-amplifier extending sensitivity from -138 dBm + 3f(GHz) dB across 10 MHz to 3 GHz.

Technical Specifications

• Operating range: 9 kHz to 3 GHz (U3841)


• Pre-amplifier range: 10 MHz to 3 GHz


• Maximum analysis bandwidth: 40 MHz


• Capture bandwidth: 100 Hz to 30 MHz (1–3 steps), extendable to 40 MHz


• Resolution bandwidth (Frequency Sweep): 100 Hz to 3 MHz (1–3 steps)


• Resolution bandwidth (FFT): 1 Hz to 400 kHz (CBW/100)


• Video bandwidth: 10 Hz to 3 MHz (1–3 steps) Sampling & Time Resolution


• Sampling rate: 500 Hz (CBW 100 Hz) to 65 MHz (CBW 40 MHz)


• Time resolution: 15.4 ns (CBW 40 MHz) to 2 ms (CBW 100 Hz) Amplitude Characteristics


• Measurement range: Displayed average noise level to +30 dBm


• Input attenuator: 0 to 50 dB (10 dB steps)


• DC input maximum: ±50 VDC


• Maximum safe input: +30 dBm (pre-amp OFF, attenuator ≥10 dB); +13 dBm (pre-amp ON, attenuator 0 dB)


• 1 dB gain compression: >-5 dBm (pre-amp OFF, f ≥20 MHz); >-25 dBm (pre-amp ON, f ≥20 MHz)


• Third-order intermodulation: 10 MHz, 2-signal separation >200 kHz)


• Residual response: 10 MHz, pre-amp OFF)


• DANL (f ≥10 MHz): Pre-amp OFF: -123 dBm + 2f(GHz) dB (f <2.5 GHz) or -123 dBm + 2.5f(GHz) dB (f ≥2.5 GHz); Pre-amp ON: -138 dBm + 3f(GHz) dB


• Amplitude accuracy: ±1.0 dB (9 kHz to 3 GHz); ±0.8 dB (10 MHz to 3 GHz)


• Inter-channel balance: ±2.0 dB (amplitude); ±15° (phase)


• RF input VSWR: <1.5:1 Sweep & Detection


• Sweep time (Spectrum): 20 ms to 1000 s


• Sweep time (Zero Span): 50 µs to 1000 s


• Detection modes: Normal, Positive peak, Negative peak, Sample, RMS, Average Electrical


• AC input: 100–120 VAC or 220–240 VAC, 50/60 Hz (automatic switching)


• Power consumption: 150 VA or less

Key Features

• Integrated spectrum, network, and time-domain analysis


• Dual-channel IQ data capture with calibration signal output


• Selectable pre-amplifier for extended dynamic range


• Attenuator control in 10 dB steps


• N-type RF connectors


• USB 1.1 interface

Typical Applications Component and system characterization, EMI/RFI measurement, signal integrity analysis, and wideband RF signal evaluation.

Compatibility & Integration USB 1.1 connectivity enables integration with external measurement systems and data acquisition workflows.