RF Test Equipment Series: Signal Generators
An RF Signal Generator is another keystone piece of RF test and measurement equipment, alongside spectrum analyzers and network analyzers. The purpose of signal generators is to create RF signals at varying power levels, frequencies, and in the case of vector signal generators, with various phase and waveform characteristics. RF signal generators are used in the testing of a wide range of RF components, devices, assemblies, and systems. The figures of merit for a signal generator are typically the power output range, frequency range, modulation capability, control interface, bandwidth, and signal sweep dynamics.
As the latest vector signal generators can also include packages that enable waveform compliance testing for standardized modulation and wired and wireless communications technology, they are also used in the testing of communications and radio equipment. These types of signal generators are often used to test communications with such devices as well as stand-ins to test the performance and behavior of the accessories and devices connected to the communications and radio devices. As such, these types of signal generators are built much like modern radio equipment, though typically with much higher frequency, greater bandwidth, and capable modulation circuitry that is now generally software defined.
Though less modern, analog signal generators are still in use that employ phase locked loop techniques to improve signal quality of tones. Modern signal generators use more complex and capable frequency synthesizer that are generally digital or software controlled. With these more updated models, phase locked loops, or even direct digital synthesizer (DDS), methods are used to generate and control the output signals. There are also signal generators that are capable of generating specialized pulsed signals for certain applications, such as radar, jamming, anti-jamming, and other Electronic Warfare (EW) and scientific applications.
Like with other of the keystone RF test equipment types, signal generators are configured as bench-top, rackmount, PC-driven via USB/Ethernet, touch-screen portable, and even as PXI card slots for modular test equipment platforms. And like other precision RF test equipment, coaxial and waveguide interconnect is generally needed to connect the test instrument to the DUTs. This accessories include coaxial cables, adapters, probes, attenuators, couplers, and etc.
Useful Signal Generator Accessories and Equipment