Amplifier Selection Tips

Amplifier Selection Tips

30/20S1G18B

  1. In general EMC amplifiers are based on various technologies and functionality, such as: Solid State, TWTA, CW, Pulse, and their class of operation - Class A and AB.
  2. Class A solid state amplifiers are generally the best choice for EMC RI and CI testing. They are the most reliable, durable and rugged compared to other amplifier classes, or types.
  3. Amplifiers offering 100% rated power with-out foldback are a good choice. Typical EMC testing exposes amps to significant VSWR and reflected power.
  4. Also look for an amp that operates without damage or oscillation with any magnitude and phase of source and load impedance.
  5. Amps with good linearity and low harmonic distortion, result in clean, reproducible and measurable signals. Again, Class A amplifiers outperform other types.
  6. Modulation (AM, FM, PM) is required by most RI and CI test standards. Ask the amp manufacturer how well modulation is reproduced and under what conditions.
  7. If planning to use a multiple tones/signals or complex waveforms to speed up testing and better represent real-world threats, a broadband amplifier is most appropriate, versus a multiband amplifier so that all tones are amplified simultaneously.
  8. Determine the amp’s required power based on losses; cable, gain (antenna), and number of tones, if used with a multi-tone generator.
  9. Rated Output Power is a manufacturer defined specification. Beware of typical, average and maximum power level descriptions. These can be misleading.
  10. Power Output @P1dB: An important rating for applications with strict linearity requirements (IEC/R&D).

Originally published at INCompliancemag.com.