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wimax systems interfering with c-band satellite terminals

• Telecom nerd filter (again): Documented instances of 802.16-2004 or 802.16e-2005 WiMax installations interfering with C-band satellite systems? 3.40 GHz to 6.425 GHz frequency range. Several months ago I came across a blog post from a VSAT service provider in Indonesia. Unfortunately I can't seem to find it again, but he was concerned the possibility of fixed WiMax (802.16) installations interfering with C-band satellite systems. C-band VSATs receive in the 3.40 GHz to 4.20 GHz range, and transmit from 5.80 to 6.425 GHz. This overlaps with the spectrum used by some fixed WiMax setups, particularly first and second generation Motorola Canopy systems that are being deployed in many developing countries. Does anyone know of a documented instance of a WiMax system partially or totally interfering with the operation of a C-band VSAT or earth station? How close was the offending WiMax setup to the VSAT dish? Was it a point-to-point LAN/MAN bridge link, or a sectorised city covering WiMax base station installed on a hilltop? Any information on the satellite terminal that was interfered with (size of dish, electronics and modem used by dish, configuration) would also be useful.

• Answer:

  It's not just WiMax that causes C-band systems problems, and in that, http://www.comsearch.com/telecom/satellite_eng.jsp#interference_analysis, in U.S. installations. And unlicensed WiMax has to back down, period. Here are several white papers from a U.S. communications engineering firm that describe such actual interference situations, and how they rode in on white stallions wearing light gray 10 gallon hats: http://www.comsearch.com/corporate/case_study_request/index.jsp?page=Analogue-to-Digital%20Earth%20Station%20Conversion&url=%7Ctelecom%7Csatellite_eng.jsp#atod.