No question, a signal generator is a significant part of any RF/microwave test bench. When purchasing signal generators on a limited budget, teams may face the dilemma of deciding what to buy. This decision can be even more difficult for companies developing radar and wireless network systems, as these applications may require a larger number of signal generators along with the need for modular capability. In the technical brief, “10 Signal Generator Features You’re Probably Paying Too Much For,” Vaunix discusses many aspects of a signal generator so that an informed decision can be made when purchasing one.
The tech brief starts out by explaining that frequency range is the key factor when contemplating a signal generator. However, frequency range can also be one reason why companies overpay for test equipment. Specifically, test teams often purchase one ultra-wideband instrument that operates at frequencies beyond what’s actually needed, so they wind up essentially paying for unnecessary performance. According to the document, a modular, self-programmable solution offers an alternative approach.
The brief then delves into phase noise. The phase-noise performance of a signal generator depends on the oscillator technology and frequency-synthesis circuitry. Furthermore, the tech brief points out that the phase noise of a signal generator is a limiting factor for only some applications, and subsequently states that paying for phase-noise performance only slightly better than what’s needed may dramatically increase the cost of the equipment.
Frequency resolution is mentioned, too, as some applications may require signals to be generated at very precise frequencies. In such cases, an extremely fine frequency resolution is critical. However, according to the document, frequency resolution of a few hundred hertz—or even higher—is adequate for most applications. Cost-effective options are available for use cases in which frequency resolution below 100 Hz isn’t essential.
Other factors mentioned include frequency-switching speed, output-power range, and harmonics, among others. Lastly, the tech brief includes a table that compares many of the signal generators currently on the market.
Vaunix Technology Corp., 7 New Pasture Rd., Newburyport, MA 01950; (978) 662-7839.
