At&T Wireless Services, Inc. v. F.C.C.

• Decision Date: 04 May 2004
• Docket Number: No. 03-1043.,03-1043.
• Parties: AT&T WIRELESS SERVICES, INC., et al., Petitioners, v. FEDERAL COMMUNICATIONS COMMISSION and United States of America, Respondents. AirCell, Inc., Intervenor.
• Court: U.S. Court of Appeals — District of Columbia Circuit

365 F.3d 1095

AT&T WIRELESS SERVICES, INC., et al., Petitioners, v. FEDERAL COMMUNICATIONS COMMISSION and United States of America, Respondents AirCell, Inc., Intervenor.

No. 03-1043.

United States Court of Appeals, District of Columbia Circuit.

Argued March 15, 2004.

Decided May 4, 2004.

On Petition for Review of an Order of the Federal Communications Commission.

L. Andrew Tollin argued the cause for petitioners. With him on the briefs were Michael Deuel Sullivan, Douglas I. Brandon, Carol L. Tacker, and John T. Scott III.

Roberta L. Cook, Counsel, Federal Communications Commission, argued the cause for respondents. With her on the brief were Robert H. Pate III, Assistant Attorney General, Robert B. Nicholson and Robert J. Wiggers, Attorneys, John A. Rogovin, General Counsel, Federal Communications Commission, and Daniel M. Armstrong, Associate General Counsel.

Michele C. Farquhar, Jonathan S. Franklin, and Lorane F. Hebert were on the brief for intervenor.

Before: SENTELLE, ROGERS and GARLAND, Circuit Judges.

Opinion for the Court filed by Circuit Judge ROGERS.

ROGERS, Circuit Judge:

In AT&T Wireless Services v. FCC, 270 F.3d 959 (D.C.Cir.2001) ("AirCell I"), the court denied all challenges except one to an order of the Federal Communications Commission granting AirCell, Inc., a waiver to operate an aircraft-based analog cellular telephone system. The court remanded to the Commission for an explanation of its conclusion that AirCell's system was unlikely to harmfully interfere with the rights of ground-based cellular telephone providers, specifically so that the Commission could explain its choice of a particular threshold signal strength above which AirCell would begin to cause such interference. In petitioning for review of the Commission's more detailed explanation in Aircell, Inc., 18 F.C.C.R.1926 (2003) ("Remand Order"), AT&T Wireless Services, Inc., Cingular Wireless LLC, and CellCo Partnership contend that the Commission's explanation on remand deviates from the reasoning in the initial order in Aircell, Inc., 15 F.C.C.R. 9622 (2000) ("Initial Order"), and, in any event, is unreasonable. We hold that the petitioners misinterpret the Commission's initial order and the breadth of the remand in Aircell I, that they have waived several of their challenges to the Remand Order by failing to seek rehearing by the Commission of its explanation on remand, and that their unwaived challenges are unpersuasive. Accordingly, we deny the petition.

I.

The background to the Commission's decision to grant to AirCell, Inc. a waiver of the rules barring the use of analog cellular telephones in aircraft, see 47 C.F.R. § 22.925 (2004), is set forth in AirCell I, 270 F.3d at 961-63. A central dispute in the initial AirCell proceeding before the Commission was how to predict whether, and if so how significantly, AirCell would disrupt the networks of existing cellular telephone providers, such as the petitioners. Because the petitioners' licenses entitle them to protection from harmful interference within their geographic service areas, see 270 F.3d at 963-64; 47 C.F.R.§ 22.911(d) (2004), any waiver allowing AirCell to operate depends upon a finding that such operation will not cause harmful interference to licenseholders. The record contains data from several test flights, in which receivers on the ground measured the strength of AirCell's signal while an aircraft, placing a call from an AirCell telephone, flew overhead. The providers and AirCell, based on this data, advocated different conclusions about the likelihood of harmful interference from AirCell's operation.

The tests were conducted in rural areas, where such harmful interference is most likely because there is less background electromagnetic noise that a cellular call needs to overcome. This permits cellular calls in rural areas to be of acceptable quality even with a relatively weak signal, but those weak signals are then more susceptible to interference than calls in suburban or urban areas, which are required to transmit at a higher strength. For the one day of test flights the Commission considered representative of how AirCell would operate in practice, July 10, 1997, AirTouch Communications submitted an analysis by Dr. William C. Y. Lee, who concluded that AirCell's calls would cause harmful interference 30% of the time they were placed while flying over a ground-based call using the same channel. He based this prediction on the premise that harmful interference to a ground call on the same frequency would occur whenever AirCell's signal strength exceeded a threshold of 124 decibels below one milliwatt, i.e. -124 dBm. The Commission rejected Dr. Lee's -124 dBm threshold as "too conservative," stated that an interference threshold of 117 decibels below one milliwatt, i.e. -117 dBm, was "more realistic for typical analog systems," and that "based on [] review of the evidence, it appears [] that use of the latter threshold would have led to a finding that AirCell would cause a significant level of harmful interference 0% of the time." Initial Order, 15 F.C.C.R. at 9631 n. 67. On that basis, the Commission affirmed the grant of the waiver to Aircell by the Bureau of Wireless Telecommunications.

In AirCell I, the court remanded on the harmful interference threshold determination, holding that the Commission had failed "to justify adequately its choice of an interference threshold," 270 F.3d at 968, and that it had not shown how it "translate[d] the raw signal data from the July 10, 1997 field test into a finding that AirCell's system `would cause a significant level of harmful interference 0% of the time' in the real world" without conducting a probability study to determine how frequently the event studied, the simultaneous use of the same channel by an AirCell call and a terrestrial call at the same location, would occur. Id. at 968-69. The court noted that the Commission's "explanation for its conclusion in AirCell's favor may be relatively simple and briefly stated," but that because the record contained conflicting explanations of the data, the court was unable to discern "why the Commission considered one interference threshold preferable to another." Id. at 968.

On remand, the Commission reaffirmed its prediction that AirCell would not cause harmful interference with ground-based cellular systems and explained its rejection of Dr. Lee's conclusion to the contrary. See Remand Order, 18 F.C.C.R. 1926. It explained that it had derived the -117 dBm figure by starting from the strength of the weakest ground-based call that could still be considered acceptable quality in a rural area, which the Commission claimed was -100 dBm, and subtracting a 17 dB "buffer," which is the industry standard for the amount by which a cellular call must exceed other signals in order to be effective. It reasoned that the -124 dBm figure used by Dr. Lee had been derived by assuming a -129 dBm environmental noise floor in quiet locations and stipulating that AirCell would cause interference with ground systems once it exceeded the noise floor by 4.76 decibels. The Commission stated that this method was erroneous because it assumed too low a noise floor and failed to justify its premise that interference to ground-based calls would become harmful at 4.76 decibels above the noise floor. The Commission also stated that even if Dr. Lee's conclusions about the relative signal strengths were correct, it would show at most that AirCell's systems could cause interference, but not necessarily harmful interference, because Dr. Lee had wrongly assumed that all interference above his -124 dBm threshold would be harmful. The Commission reasoned that the 17 dBm buffer was "significantly more buffer than is necessary to prevent harmful interference," and that an AirCell signal would not cause harmful interference until it "seriously degrades, obstructs, or repeatedly interrupts" a ground-based call, which, the Commission stated, would not occur until a "very substantial (e.g., 7 dB or more) excess over an [interference threshold]." Id. at 1935-36.

Reviewing the test data from the July 10, 1997 test flights, the Commission on remand showed that AirCell's mean signal strength exceeded the -117 dBm threshold on only on one of the 24 test flights, and then only trivially. See id. at 1936-37. The test data also "do not show AirCell received power sustained at anywhere near the -110 dBm level that would constitute harmful interference." Id. at 1937. On the basis of the fact that AirCell's mean signal strength almost never reached -117 dBm on the test flights, and that its sustained signal strength came nowhere close to -110 dBm, the Commission explained that it was unnecessary to conduct a probability study. The July 10 test flights measured AirCell's signal under the conditions when it was most likely to cause interference (i.e., when an AirCell phone places a call while flying over a ground-based phone using the same channel). Therefore, because AirCell calls would not cause harmful interference even under the worst-case scenario, it was unnecessary to assess the probability of the worst-case scenario occurring. The petitioners did not seek rehearing of the Commission's Remand Order, see 47 U.S.C. § 405(a) (2004), but filed this petition for review pursuant to 47 U.S.C. § 402(a), and a motion for summary reversal and vacatur of the Remand Order and the underlying waiver grant. The court denied summary reversal. See AT&T Wireless, Inc. v. FCC, No. 03-1043, 2003 WL 21767625 (D.C.Cir. July 15, 2003) (per curiam).

II.

The sole question now before the court is whether the Commission's order satisfies the remand in AirCell I. The court is generally the authoritative interpreter of its own remand, see FCC v. Pottsville Broad. Co., 309 U.S. 134, 141, 60 S.Ct. 437, 440, 84 L.Ed. 656 (1940), and in light of its previous opinion, the court owes no deference to the Commission's...