Advantest R3131 9 kHz to 3 GHz Spectrum Analyzer

The Advantest R3131 is a spectrum analyzer that performs precise signal analysis across 9 kHz to 3 GHz, making it essential for component testing, wireless communications development, and electromagnetic interference (EMI) assessment. The instrument delivers phase noise performance of ≤ −100 dBc/Hz at 20 kHz offset and resolution bandwidth settings from 1 kHz to 1 MHz with bandwidth accuracy of ±20%. Frequency reading accuracy follows ± (Frequency reading × Frequency reference accuracy + Span × Span accuracy + 0.15 × Resolution bandwidth + 1 kHz), while frequency span accuracy is ≤ ±3%.

The marker counter provides 1 Hz to 1 kHz resolution with accuracy of ± (Marker frequency × Frequency reference accuracy + 1 LSD) for S/N ≥ 25 dB and SPAN ≤ 200 MHz.

Technical Specifications

Amplitude measurement ranges from +20 dBm to average noise level. Maximum safe input is +20 dBm with 20 dB internal attenuation (R3131) or +30 dBm with 30 dB attenuation (R3131A). The calibration signal operates at 30 MHz, −20 dBm ±0.3 dB. Video bandwidth spans 10 Hz to 1 MHz with sweep times from 50 ms to 500 s. Selectivity (60 dB:3 dB ratio) is ≤ 15:1. Frequency stability delivers residual FM of ≤ 100 Hzp-p/100 ms in zero span mode. Frequency reference accuracy is ±2 ppm/year with ±5 ppm tolerance across the operating temperature range. The optional tracking generator covers 100 kHz to 3.0 GHz with output levels from 0 dBm to −59.9 dBm in 0.1 dB steps. Output level accuracy is ≤ ±0.5 dB at 30 MHz and −10 dBm (20°C to 30°C).

Key Features

• AM/FM demodulator with burst signal analysis and trigger synchronization


• Automatic pass/fail limit testing


• Auto tune and power measurement functions with counter capability


• GPIB (IEEE-488) interface for remote control and data transfer


• Serial interface via D-SUB 9-pin and printer interface (D-SUB 25-pin, ESC/P and PCL compatible)


• 3.5-inch floppy disk drive (1.4 Mbyte, MS-DOS format) for data logging


• External trigger input via BNC jack (10 kΩ nominal, DC coupling)


• Reference input: 50 Ω BNC jack (10 MHz REF)


• Phone output via mini monophonic jack (8 Ω)

Typical Applications

• Component and subsystem characterization


• Wireless communications system development and validation


• EMI/RFI assessment per CISPR 16 standard


• Burst signal and modulation analysis

Compatibility & Integration Power supply accepts 100/200 VAC with auto switching (100–120 V or 220–240 V, 50/60 Hz). Power consumption is 200 VA maximum at 100 VAC. Operating conditions are 0°C to +50°C at 85% humidity. Dimensions are 424 mm (W) × 177 mm (H) × 300 mm (D); weight is 12 kg or less.