Which Siglent RF signal generator do you need? IQ & modulation compared

Modulation capability is what really separates RF signal generators — especially for testing receivers and digital links that use IQ modulation. Siglent's SSG families cover the whole range from clean analog carriers to full internal vector generation; the differences below decide which one your test bench needs.

The three capability tiers

• Analog generators (SSG3000X, SSG5000A): precision CW carriers with AM/FM/PM and pulse modulation — ideal for LO substitution, blocking tests and level calibration. No IQ.
• External-IQ models (SSG3000X-IQE): add wideband external I+Q inputs (to ~200 MHz bandwidth) — you supply the baseband from an arbitrary generator such as an SDG6000X or SDG7000A running SigIQPro.
• Vector generators (SSG5000X-V, SSG6000A series): internal IQ modulator and baseband — generate digitally modulated signals (QAM, OFDM, standard-based) directly from the front panel or SigIQPro, no external baseband hardware.

How to choose

• Receiver sensitivity or link testing with digital modulation → vector model
• You already own a dual-channel SDG with IQ option → the -IQE route is the budget path to IQ
• Pure carriers, EMC immunity work, LO duty → an analog SSG does it at the best price
• Check the frequency ceiling last: SSG3000X to 3.2 GHz, SSG5000X to 6 GHz, SSG5000A to 20 GHz, SSG6000A to 40 GHz