[44net] OT: FCC Invites Public Comment on Petition Affecting 10-10.5 GHz Band

Sorry for the OT, but this does effect us all in the US. The FCC has invited public comment on a Petition for Rule Making (RM-11715) that would make a significant portion of the 10.0 to 10.5 GHz band available for wireless broadband services. The Petition by Mimosa Networks Inc proposes a band plan for 10.0 to 10.5 GHz that, it says, would protect frequencies most often used by radio amateurs. The petition hinges on FCC adoption of rule changes that would put the 10 GHz band under Subpart Z of the Commission’s Part 90 rules. Subpart Z currently sets out regulations governing wireless licensing, technical standards, and operational standards in the 3650 to 3700 MHz band. I've made my comments on this, and would invite other hams to do so. I feel I'm uniquely qualified to see this from both side as I owned a WISP before. http://mimosa.co/support-our-petition.html is the link mimosa networks has on how to comment. I'd encourage you to comment on this, as it will negatively affect the amateur radio allocation on the most popular microwave band. Feel free to steal from my comments below: Comments on RM-11715 Petition for Rulemaking from Mimosa Networks regarding the 10.0 to 10.5 GHz band. I am uniquely qualified to comment on this petition as both a licensed Amateur Radio operator (callsign KB9MCI), and former owner of a Wireless Internet Service Provider, Illiana Internet LLC from 2000-2006. Currently I work as Consulting Engineer in the Cellular and Service Provider space. I have built and operated many amateur radio microwave stations in the 3CM (10 GHz) band. Wireless Internet Service Providers (WISPs) present themselves as a group providing Internet to the rural and underserved communities of the USA. To an extent this is true, however their services are not a substitute for fiber and wire line carriers. WISP’s are typically a small business, lacking the capital and skilled engineers needed for day-to-day operation of a multi-site wireless network. There is little incentive to design with good RF engineering practices, as most WISP’s lack the ability to hire competent RF engineers, and supply them with the tools they would need (Spectrum analyzer, test equipment, etc.). This lack of RF engineering knowledge leads to inevitable interference between competing operators, and other users of the ISM and UNI bands. As interference goes up, power and antenna size invariable increases (even exceeding the EIRP FCC rules) to maintain service to their customers. This cannot be allowed to happen in a band shared with weak signal users such as the Amateur Radio Service. I am in favor of more spectrum for WISP’s and ideally this would be sub 7 GHz, however if it must be shared spectrum, it needs to be shared with users that can tolerate a higher noise floor. Weak signal services such as amateur radio or GPS satellite should not share with such use. Spectrum should be aligned with international users as well in my opinion; a 10GHz band use under the Mimosa proposal would be incompatible with this. The requirements in the 10.0 to 10.5 GHz band as proposed allow a non-restricted contention based protocol. This should not be permitted in any case. The amateur radio use of this band is based on such contention-based protocols (i.e. listening before transmitting). This will encourage WISP users of this band to run hotter systems to “talk” over competing systems not unlike what has happened in the ISM and UNI bands. This need for a restricted contention-based protocol must be retained in any case. DFS is proposed to avoid co-channel operation with only radar systems. This excludes the amateur use of these bands. Further threshold is -64 dBm, which is well above level amateur systems operate at. Amateur use of the 10 GHz band is not “strong signal” fixed operations as point-to-point microwave use is. Rather, Amateur use is characterized by weak signals and “pushing the envelope” of RF path link budget. Amateurs may employ CW (A1A), SSB (J3E), FM (F3E) and other emissions at these frequencies. DFS needs to be a requirement for not only radar systems, but amateur systems as well. Even with DFS as a requirement the proliferation of cheap non-carrier grade WISP equipment from foreign vendors has the potential to be “unlocked” with DFS and even the proposed protected bands at 10.350-10.370 and 10.450-10.500 GHz being illegally used by untrained operators. Further, most equipment can be “hacked” to use such restricted channels. This last point is not to be dismissed, as there have been numerous actions by the FCC of 5.4 GHz interference from WISP’s to TDWR RADAR. (http://www.fcc.gov/encyclopedia/weather-radar-interference-enforcement) Others commenting in favor of this NPRM have been the recipient of Notices of Liability and Fines for repeated violations of the requirements to operate legally in the 5.4 GHz band (ex. EB-09-SJ-0014 – Aeronet Wireless Broadband, San Juan, PR). What assurance can these operators give the commission and the amateur radio community that they will not do this again? If this NPRM is implemented and such interference effects amateur stations it would be almost impossible for the commission to enforce, as amateur stations are not fixed or as critical as TDWR RADAR stations are. This would be an incompatible use. In 10 GHz amateur operation using narrow bandwidth useful signals may be below the -174 dBm/hz common minimum discernible signal noise floor, especially in amateur satellite service, or in Earth Moon Earth (EME) where signals are reflected off the moon. Further for DFS to work, these narrow band signals would need to be detected by a receiver with a 20 MHz receive bandwidth. In these wide band commodity receivers an amateur radio signal at -130 dBm would not be detected even in the absence of signal. As DFS is not required to act on a signal less than -64 dBm most amateur radio communication use would not trigger it. Even more so in the amateur satellite service from 10.450-10.500 GHz, severe interference would be caused by normal operations by the WISP radios raising the effective noise floor. An amateur satellite receiver has a wide band pre-amplifier, such strong signals even 20 MHz removed from the intended signal would require expensive and high signal loss pre-selective filters. Would Mimosa networks intend to pay for these filters for every amateur radio receiver? What of current satellite receivers in orbit that cannot be retrofitted? The proposed strong signal use adjacent to the Amateur Satellite service at 10.450-10.500 GHz by channel 21 is without technical precedent. A receiver on a satellite would hear every strong broadband transmitter in its footprint as it passes over the US. This interference would cause amateur radio operators far removed from the transmitter to be unable to communicate through satellites they had previously been able to communicate through. I would refer to the LightSquared Petition to the FCC for use of ancillary terrestrial component equipment in its spectrum and the impact on GPS receivers. Based on these facts I would ask the Commission to deny the Mimosa petition. 73's -- Bryan Fields 727-409-1194 - Voice 727-214-2508 - Fax http://bryanfields.net