AFE7444: Frequency hopping in Tx side and vary LO with 1Hz resolution

No, not quite.  The AFE74xx has a 32-bit NCO.  The exact step size is dependent on the data converter sampling clock.  The min resolution is: Fclk / 2^32.  You can achieve step sizes that are generally close to 1 Hz, but not exactly unless you support a 2^32 Hz clock.  The reasonable 6 GHz clock would yield a step size of about 1.4 Hz.

--RJH