REC75 – 447 – MOD RECOMMENDATION 75 (REV.WRC-15) Study of the boundary between the out-of-band and spurious domains of primary radars using magnetrons The World Radiocommunication Conference (Geneva, 2015), considering a) that the principal objective of Appendix 3 is to specify the maximum permitted level of unwanted emissions in the spurious domain; b) that the out-of-band and spurious domains of an emission are defined in Article 1; c) that Recommendation ITU-R SM.1541 specifies the boundary between the out-of-band and spurious domains for primary radars, and that the boundary is related to the emission mask based on the −40 dB bandwidth; d) that Appendix 3 refers to Recommendation ITU-R SM.1541; e) that Recommendation ITU-R M.1177 describes the techniques for measurement of unwanted emissions of radars, recognizing that there is a possibility that calculated values for the −40 dB bandwidth related to unwanted emissions of primary radars using magnetrons underestimate the actual bandwidth, recommends that ITU-R study calculation methods for the −40 dB bandwidth necessary for the determination of the boundary between the spurious and out-of-band domains of primary radars using magnetrons, invites administrations to participate actively in the above studies by submitting contributions to ITU-R.