Reydel,
Whilst not excluding the chances of jamming from a surface ship - I have witnessed Mutual Interference from shore installations whilst embarked. This was greated with wails of 'They're jamming us they know we're coming!' but was in all probability simply two systems competing for the same bit of the EM spectrum.
This happened all the time with airborne radars - in the Sea Harrier the other pair on CAP, or a Sea Harrier in the Red Air role almost always led to significant MI.