Signal Hound’s new 50 MHz to 6 GHz vector signal generator (VSG), the VSG60A, offers the performance and agility of a “serious” VSG at a fraction of the cost. A low phase noise, agile local oscillator with 200 µs switching time enables frequency hopping spread spectrum testing. Using digital oversampling, a dual, 14-bit digital-to-analog converter runs at 2x or 3x the I/Q symbol rate to provide a flat, clean baseband: typically, ±0.25 dB for 20 MHz and ±0.5 dB for 40 MHz. The VSG’s output power ranges from +10 to −55 dBm.

The VSG60A has 40 MHz streaming modulation bandwidth and pre-programmed modulation types, including Wi-Fi, QAM, PSK, CW, pulse and multi-tone. With a 1 GHz carrier, 1 MSPS, 16-QAM, 0.35 alpha raised cosine signal, the error vector magnitude is typically 0.3 percent, and the typical phase noise is −114 dBc/Hz at 1 kHz offset and −135 dBc/Hz at 1 MHz offset.

An internal, digitally-adjustable, voltage-controlled, temperature-compensated crystal oscillator ensures frequency errors are minimized over temperature. Alternatively, an external 10 MHz input may be used to achieve 0 ppm frequency error. Stability over temperature is ±0.28 ppm, and typical aging is less than 1 ppm/year. A trigger output is available to synchronize the VSG60A with other test equipment.

Signal Hound provides a custom API to continuously stream I/Q data to the VSG60A at an arbitrary sample rate up to 51.2 MSPS. The software can also load a CSV format binary short integer or binary floating point I/Q file. Corrections are applied automatically as the data is streamed to the instrument.

Priced at $2,445, the VSG is an excellent value, rivaling the performance of more expensive instruments.

Signal Hound
Battle Ground, Wash.