I am trying to generate an 11 MHz pulsed chirp signal with center frequency of 4 GHz at a power level of +10 dBm. I have an arbitrary waveform generator that can generate the correct chirp signal, but can only supply a power level of -40 dBm. I am determining this using a spectrum analyzer, and measuring the average amplitude of the 11 MHz band. The waveform on the spectrum analyzer is generally flat, with maybe +/- 0.5 dBm variation.
So I added two amplifiers in series (part number ZVA-213-S+). As far as I can tell this should give me a minimum of 40 dB gain, or a typical of 50 dB gain. Unfortunately there is some kind of saturation happening, and I am maxing out at around -16 dBm. I can lower the power level of the arbitrary waveform generator until I see the power level dropping, but once I start increasing the power level, I can't get past -16 dBm even though the waveform generator claims its output power is still got room to increase. The spec sheet of the amp claims that it can provide an output of +33dBm, typically.
I repeated this test using a single tone pulse at the same frequency. With this I could see the expected gain of 50 dB.
I verified everything was fine in terms of providing power to the amplifier. It's the recommended 12 VDC, and the power supply can provide up to 5 amps.
Is there some fundamental difference when applying a chirp signal to an amplifier versus a single tone that would cause this?