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D. Throughout Its Quarter-Century History, Qualcomm Has Pioneered

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D. Throughout Its Quarter-Century History, Qualcomm Has Pioneered D. Throughout Its Quarter-Century History, Qualcomm Has Pioneered The Development OfMany Innovative Wireless Services, Technologies, And Applications, Including The Current Air-Ground Communications System For more than a quarter century, Qualcomm has pioneered the development ofmany innovative wireless technologies. As the FCC knows, the company invented the Code Division Multiple Access ("CDMA") -based cellular communications technology, which is used in the U.S. and many other countries around the world for terrestrial wireless voice and broadband communications and countless mobile broadband products and services. The current Aircell air- ground system that operates in the 850 MHz band was designed by Qualcomm and uses the company's CDMA technology. Qualcomm also has developed Orthogonal Frequency Division Multiple Access ("OFDMA") -based cellular technologies (e.g., LTE) that power the next- generation terrestrial mobile broadband networks operated by wireless carriers throughout the U.S. and around the world. Qualcomm is continuously innovating in the wireless space. Qualcomm has invested more than $16.0 billion in R&D ofwireless technologies since the company's founding in 1985. In fiscal 2010 alone, Qualcomm spent $2.55 billion, or 23% ofits revenues, on R&D ofa wide range ofadvanced wireless technologies. These enormous expenditures have enabled Qualcomm to invent many ofthe technologies fueling the exponential growth in mobile broadband usage. And, through its Technology Licensing ("QTL") business unit, Qualcomm broadly licenses its technology to more than 180 handset and infrastructure manufacturers worldwide that make network equipment, handsets and other consumer devices, and develop mobile services and applications for cellular networks based on 3G and 4G technologies. Qualcomm's chip division, Qualcomm CDMA Technologies ("QCT"), is the world's largest provider ofwireless chipset technology that is used in cell phones and consumer electronics devices. QCT's chipsets support all the major terrestrial mobile frequency bands, the -22- full gamut ofstandardized, globally harmonized 3G and 4G wide area mobile broadband and cellular technologies, GPS-based and GLONASS-based location tools, Bluetooth, Wi-Fi, and many operating systems, such as Android, Windows Mobile, Symbian, and Qualcomm's own Brew Mobile Platform. Furthermore, as noted above, Qualcomm currently operates its OmniTRACS service, a mobile satellite service within the band proposed herein for the Next-Gen AG system. For more than two decades, the highly successful OmniTRACS mobile communications and information service has allowed commercial trucking and construction companies to proactively manage their equipment fleets to improve productivity and security.47 As such, Qualcomm is fully cognizant ofthe interference protection needs ofGSO satellite operations (like OmniTRACS) and has meticulously designed the innovative Next-Gen AG communications service to fully protect GSO satellite operations, and avoid causing harmful interference to radio astronomy and TDRSS operations. The last thing Qualcomm would seek to do is to introduce a new communications service that introduces any risk ofinterference to existing GSO operations, especially Qualcomm's own OmniTRACS service. -23- CONCLUSION Qualcomm respectfully requests that the FCC seek comments on the attached Petition for Rulemaking and thereafter move promptly to issue a Notice ofProposed Rulemaking to adopt the proposed rules and create a Next-Generation Air-Ground communications service at 14.0 to 14.5 GHz. Qualcomm looks forward to working with the Commission and all interested stakeholders to enable multi-gigabit-per-second air-ground broadband communications technology to support the exploding population ofmobile broadband devices and applications well into the future. Respectfully submitted, QUALCOMM INCORPORATED Dean R. Brenner Vice President, Government Affairs John W. Kuzin Senior Director, Regulatory 1730 Pennsylvania Avenue, NW Suite 850 Washington, DC 20006 (202) 263-0020 Attorneysfor QUALCOMMIncorporated Dated: July 7, 201] -24- Appendix A Interference Protection Analysis A-I 1. Next-Gen AG System Description The proposed Next-Gen AG system provides coverage to aircraft flying above the Continental United States ("CONUS") using about 150 Ground Stations ("GSs") located on the earth's surface. The proposed system would operate in the Ku band, at 14.0 to 14.5 GHz, and use a Time Division Duplex ("TDD") communications mode with an OFDMA-based air interface to support high-speed data connections between the GSs and in-flight aircraft. The GSs would use beams that are narrow in azimuth (2° wide) and advanced antennas that operate with an isoflux pattern in elevation. The isoflux antenna pattern in elevation means that the GS antenna gain decreases in direct proportion to its distance from the aircraft; that is, as the aircraft flies closer to a GS and the antenna elevation angle needed to service the aircraft increases, the antenna gain ofthe serving GS decreases proportionately while maintaining an adequate Carrier-to-Noise (C/N) ratio. This advanced system design allows the Next-Gen AG system to avoid interference to satellite systems and other incumbent services while providing high-speed, low latency, broadband connectivity to aircraft. As shown below, the Next-Gen AG system will use this and other advanced techniques to provide full protection to the uplinks of Fixed Satellite Service ("FSS") Geo-Synchronous Orbit ("GSO") satellite operations, future Non Geo-Synchronous Orbit ("NGSO") satellite systems, and other incumbent users. NGSO satellite systems are in non-equatorial orbits and could be observed from any direction in the hemisphere above Next-Gen AG GSs (and aircraft). While NGSO satellite operations are not currently in the 14.0 to 14.5 GHz band, they may be authorized for operation in the future, and Qualcomm's system is designed to protect a typical NGSO system as set forth herein. The Next-Gen AG system GSs use phased-array technology to form narrow beams so that several beams can be simultaneously active on the same frequencies without destructive mutual interference via space division re-use. These beams, ofcourse, will be sufficiently spatially separated to leave room for multiple, simultaneously active beams. TDD multiplexing is used to allow GSs to serve several aircraft via adjacent or overlapping beams. Frequency division multiplexing also is used to service aircraft whose GS beams would otherwise have harmful inter-beam interference. In the OFDMA-based air interface, for example, this is achieved by providing each aircraft with a disjoint subset ofthe tones in the full signal band. A-2 Each Next-Gen AG system GS is designed to point its beam away from the GEO-arc and provide substantial roll-offtoward the GEO-arc to avoid any potential interference to the GSO satellites. As shown in Figure A.I, planes will be served by beams that cover an area in azimuth that generally is ± 60° from true north (that is, a 120° angle). Also, each GS will form one or more narrow (2°-wide) beams for communications with aircraft. By pointing away from the GEO-arc (which is directly above the equator ofthe earth) and by using narrow beams that sharply fall off outside the beam coverage region, any potential interference to GSO satellite operations is reduced to negligible levels, as explained in detail below. The isoflux property ofthe GS antenna in elevation also is designed to protect potential future NGSO satellites. As the aircraft approaches a GS, and the elevation angle toward the plane from the GS increases, the transmit power for the GS-to-aircraft forward link ("FL") is reduced according to the diminished path loss, thereby protecting NGSO operations. As explained below, as an aircraft approaches a GS and the elevation angle between the plane and the GS increases above 10° (which occurs at a distance of60 kIn or less from the aircraft to the GS), the system begins the process ofhanding offcommunications to another GS. Another means of protecting NGSO satellites is to have the Next-Gen-AG system use the ephemeris information on the NGSO satellite locations and turn down its FL transmit power for that limited amount oftime that the GS, served aircraft, and NGSO satellite are all in alignment. The aircraft antenna, which transmits RL communications, will be pointing downward from the aircraft (i.e., below the horizon) and thus have a high roll-offat angles toward the GEO-arc. The aircraft transceiver and antenna system is designed to be small, low-cost, and low-weight. In addition, the GS receive antenna will be a very high gain antenna to allow the aircraft to transmit with a very low EIRP. These two factors limit greatly the potential interference to GSO satellite operations. The Next-Gen AG system or systems will operate in 500 MHz ofspectrum currently occupied in large measure by GSO satellite systems. As shown in Figure A.I below, the Next-Gen AG GS service areas are hexagonal regions that cover CONUS with each GS located in the southernmost A-3 corner ofeach hexagon, radiating northward. The GSs will use a "point north" concept, similar in concept to what has been used for terrestrial systems in other bands and found acceptable.48 215 km, GS Row Spacing GS Locations 248 km, GS Spacing [ Figure A.I. Next-Gen AG Ground Stations Configuration From the southernmost corner ofeach GS service area, the angular coverage range is nominally ± 60° from true north, outside ofwhich the aircraft is handed offto another GS. There will be some overlap with neighboring service areas to ensure successful hand-offs between GSs. In the southernmost row ofGSs, aircraft flying at azimuth angles greater than ± 60° from the GS will be served by the nearest GS, but the EIRP ofthe serving beam will be reduced so as to meet the requirement ofnot interfering with the GEO-arc; in this case, the data rate to aircraft very close to the southern border may need to be reduced. However, by allocating greater transmission time to these planes, adequate throughput to the planes can be maintained.
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