1 8 0 0 M S T R E E T , N W S U I T E 8 0 0 N W A S H I N G T O N , D C 2 0 0 3 6 T E L 2 0 2 . 7 8 3 . 4 1 4 1 F A X 2 0 2 . 7 8 3 . 5 8 5 1 W W W . W B K L A W . C O M S E A N T. C O N W A Y 2 0 2 . 3 8 3 . 3 4 1 2 S C O N W A Y @ W B K L A W . C O M October 1, 2020 VIA ECFS Marlene H. Dortch, Secretary Federal Communications Commission 445 12 th St. SW, Room TW-B204 Washington, DC 20554 Re: Notice of Ex Parte : Use of the 5.850-5.925 GHz Band, ET Docket No. 19- 138 Dear Ms. Dortch: On September 29, 2020, representatives of the 5G Automotive Association (“5GAA”) spoke by telephone with Ron Repasi, Ira Keltz, Monisha Ghosh, Paul Murray, Jamison Prime, Michael Ha, Jamie Coleman, Brian Butler, Howard Griboff, Syed Hasan, Patrick Forster, and Rodney Small, all of the Commission’s Office of Engineering and Technology, regarding the record in the above-referenced proceeding. The following representatives of 5GAA member companies participated in the call: • Ford Motor Company : John Kwant, Ivan Vukovic, Nick Baracos, Syed Ahmad, Gurunath Vemulakonda • General Motors : Krishnan Hariharan , Reagan Payne, Scott Geisler • Fiat Chrysler Automobiles : Andres Castrillon, Sushanta Das • Audi of America : Brad Stertz • Daimler North America : Jess Nigro • Qualcomm : Dean Brenner, John Kuzin, Tevfik Yucek • Nokia : Jeffrey Marks • Ericsson : Mark Racek 5GAA was also represented by its Chief Technology Officer Maxime Flament, Zociana Stambolliu of its Secretariat’s office, and Mark Settle and the undersigned, both of Wilkinson Barker Knauer, LLP.
Marlene H. Dortch October 1, 2020 Page 2 The 5GAA members explained that 5GAA has proposed two distinct paths for modernizing the Commission’s rules to unleash direct Cellular Vehicle-To-Everything (“C-V2X Direct”) communications and thereby deliver critical safety benefits to American consumers and travelers. 1 Under the greatly preferred first option, the Commission would adopt its proposal to allocate the upper portion of the 5.9 GHz band for Basic C-V2X Direct services and also reallocate the lower portion of the 5.9 GHz band for Advanced C-V2X Direct services. 2 Under the second option, which assumes the Commission reallocates the lower 45 MHz portion of the 5.9 GHz band for unlicensed operations, the Commission would (1) allocate the upper 30 MHz of the 5.9 GHz band for C-V2X Direct, (2) impose modest safeguards on unlicensed use of the lower 45 MHz portion of the band to prevent harmful interference by unfettered unlicensed operations to C-V2X Direct, and (3) identify 40 MHz of dedicated, mid-band spectrum elsewhere for Advanced C-V2X Direct. 3 Should the Commission choose to reallocate the lower portion of the band for unlicensed operations, the 5GAA representatives stressed the critical importance of adopting rules that protect C-V2X Direct from harmful interference. To that end, engineering teams from Ford and General Motors co-presented the results of recent, real-world interference testing assessing the harmful impact of unwanted unlicensed emissions on C-V2X Direct safety services. This testing effort—which involved vehicles equipped with C-V2X equipment—was conducted by an automotive consortium (the “C-V2X Consortium”) comprised of Ford, General Motors, Hyundai, Nissan, and Qualcomm over the 1 Cellular Vehicle-to-Everything (“C-V2X”) leverages 4G and 5G technologies to support two complementary communications modes: C-V2X Direct (called PC5 in Third Generation Partnership Project (“3GPP”) specifications) and C-V2X network (called Uu in the 3GPP specifications) communications. C-V2X Direct mode enables (1) vehicle-to-vehicle communications, which are used to communicate safety information between nearby vehicles to improve traffic flow and prevent collisions; (2) vehicle-to-roadside infrastructure communications ( e.g. , traffic signals, variable message signs, etc.), which are used to communicate safety and traffic information, prevent accidents associated with roadway conditions, and improve traffic efficiency; and (3) vehicle-to-pedestrian communications, which are expected to be used to communicate safety information between vehicles and other road users, such as pedestrians, bicyclists, scooter riders, etc., to prevent accidents. To augment these direct communications, C-V2X’s network mode capabilities allow vehicles to communicate less time-sensitive information using cellular networks. 2 See Comments of 5GAA, ET Docket No. 19-138, at 22-45 (filed Mar. 9, 2020). 3 See id.; see also Reply Comments of 5GAA, ET Docket No. 19-138, at 12, 17-21 (filed Apr. 27, 2020).
Marlene H. Dortch October 1, 2020 Page 3 course of eight months in Farmington Hills, Michigan. The C-V2X Consortium’s published test presentation was presented at the meeting and is attached hereto. 4 The C-V2X Consortium evaluated interference to C-V2X Direct safety services caused by in-vehicle unlicensed operations in the lower 45 MHz. Specifically, the testing measured C- V2X Direct performance in the presence of an in-vehicle unlicensed access point operating under the Wi-Fi Alliance’s proposed outdoor out-of-band emissions mask for the lower 45 MHz. 5 These results were then compared to C-V2X Direct baseline performance in which no such in- vehicle unlicensed operations occurred. The C-V2X Consortium took these measurements in three common obstructed view traffic scenarios. 6 The C-V2X Consortium’s testing confirms that in-vehicle U-NII-4 unlicensed operations significantly degrade C-V2X Direct performance. For example, C-V2X Direct’s effective range was reduced by more than 50% in many instances when subject to harmful unwanted unlicensed emissions. In fact, in one non-line-of-sight intersection scenario involving vehicle-to-vehicle safety messages, effective range fell by more than 90%. 7 The following chart summarizes the C-V2X Consortium’s testing results with roof- mounted C-V2X Direct antenna: 8 4 See Cellular V2X Device-to-Device Communications Consortium, Assessment of Wi-Fi Interference to C-V2X Communications Based on Proposed FCC 5.9 NPRM, Sept. 28, 2020, https://pronto-core-cdn.prontomarketing.com/2/wp-content/uploads/sites/2896/2020/09/CAMP- CV2X-WiFi-Interference-Testing-Results-v6.11.3.pdf (“C-V2X Consortium Report”). 5 See Comments of the Wi-Fi Alliance, ET Docket 19-138, at 8 (filed Mar. 9, 2020) (“ For an outdoor device, all emissions at or above 5.925 GHz sh[ould] not exceed an EIRP of −27 dBm/MHz increasing linearly to -5 dBm/MHz at 5.895 GHz.”). 6 As 5GAA previously has described, one of C-V2X Direct’s key benefits is its ability to identify hidden hazards and changing conditions beyond a driver’s line of sight. 7 See C-V2X Consortium Report at 25-26 (showing that C-V2X Direct communications on Channel 180 between a receiving vehicle and an approaching/transmitting vehicle fell from a baseline effective range of 420 meters to 40 meters when unwanted emissions from in-vehicle U- NII-4 operations were introduced). 8 Id. at 26.
Marlene H. Dortch October 1, 2020 Page 4 The C-V2X Consortium also tested configurations using side-mirror C-V2X antennas operating in Channel 183. Those results are summarized in the below chart: 9 Unwanted unlicensed emissions meaningfully impact traveler safety. A reduction in C- V2X Direct’s range affects the traveling speeds at which this technology can support safety applications. For instance, the Electronic Emergency Brake Light (“Brake Light”) application provides warnings of a hard braking event ahead, which are particularly useful if a driver’s view is obstructed by other vehicles or bad weather conditions. In one scenario, baseline C-V2X Direct safety communications could support Brake Light warnings at relative speeds up to 68 mph. 10 Yet, when hindered by unwanted emissions from in-vehicle U-NII-4 operations, C-V2X Direct could support Brake Light warnings at a relative speed of only 45 mph. 11 Because 9 Id. at 30. 10 See id. at 19. 11 See id .
Marlene H. Dortch October 1, 2020 Page 5 relative speeds often exceed 45 mph, in-vehicle U-NII-4 access points would significantly reduce the instances in which American travelers benefit from Brake Light warnings. The 5GAA representatives also addressed a number of other issues recently raised in the docket and relevant to the C-V2X Consortium’s testing: Packet Error Rates (“PER”) . The 5GAA representatives explained that PER is a widely used indicator of the potential for harmful interference. To that end, the 5GAA representatives noted the steep and unpredictable spike in PER that occurs at certain distances when C-V2X Direct is subjected to unwanted unlicensed emissions from in-vehicle U-NII-4 operations. Unlicensed Duty Cycle Levels. Ford’s engineers explained that the C-V2X Consortium employed a lower unlicensed duty cycle than that observed in Ford’s earlier real-world measurements. Specifically, while Ford previously measured a 75% duty cycle in peer-to-peer direct file transfer tests, the C-V2X Consortium’s testing employed a more conservative Wi-Fi duty cycle of 60%. 12 Because nearly any particular unlicensed device could be operating at high duty cycle levels, stakeholders must account for such high levels when assessing interference. Pursuant to the Commission’s rules, this notice is being filed in the above-referenced docket for inclusion in the public record. Please contact me should you have any questions. Sincerely, /s/ Sean T. Conway Sean T. Conway Counsel to the 5G Automotive Association cc: Meeting participants Attachment 12 See id. at 12.
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