Rec. ITU-R RA.1237 … PROTECTION OF THE RADIO ASTRONOMY SERVICE FROM UNWANTED EMISSIONS RESULTING FROM APPLICATIONS OF ...
ANNEX 1 … Interference to radio astronomy from unwanted (spurious and out-of-band) emissions
1 Introduction
2 Spurious and out-of-band emissions from digital modulation
3 Interference levels for radio astronomy
4 Interference from satellites
5 Unwanted emissions from satellites of particular concern to radio astronomy
    5.1 Direct sequence spread spectrum
    5.2 Phase modulation of digital signals
6 Spurious and out-of-band emissions from terrestrial transmitters