just a foot note; As a part of stealth concept they use low probability of intercept (LPI) datalinks on the F-22 and the F-35 series, funy thing is until recently F35 and F 22 could not share data with each other but only with their kind. İt was a huge handicap. They are working on it. Now they can share data with each other via a third plane, in one experiment with an U 2S with communications gateway payload guess it was last year.
But you have a point they can and they are using Link 16 in some cases, when They use link 16 you have higher chances to spot and track the aircraft via those emissions. in Full stealth mode they only use The MADL and IFDL systems which are both designed to be low probability of intercept/low probability of detection (LPI/LPD) systems that enable F-35 and the F-22 to communicate with their kind while still remaining as stealthy as possible
As DARPA puts it Millimeter wave links provide physical security, but pose networking challenges!