I'm evaluating TX performance of AD9361.
Then, I found a problem.
When configuring AD9361 as TX frequency = 1000MHz and ATT = 89.75dB (max),
signal level of the 4th harmonics (HD4) becomes larger than fundamental signal (1000MHz, CW).
CW (1000MHz) : -80.4dBm
HD4(4000MHz) : -75.9dBm
Does anyone advise me the reason of this behavior?