I am working with ADF4159-ADF5901-ADF5904 chips to perform FMCW radar application. I have observed that when I use 100us up and down chirp with 250 MHz sweep bandwidth, I am observing that the output power of ADF5901 is stable during 1.4 ms. What I mean by this is that ADF5901 transmits chirps (7*200us) with stable output power and after that time output power is changing almost 0.5to1dB. This issue continues periodically with a period of 1.4 ms.
I wonder what the reason for that will be
1. Is there a periodic calibration in ADF5901 after initialization?
2. Is there a way to keep output power stable from chirp to chirp?
3. Is there a limit for output power stability?
4. Do you have any suggestions for us to fix the issue?