Attachment reply comments

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REPLY TO COMMENTS submitted by Verizon Wireless

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2001-08-30

This document pretains to SAT-STA-20010724-00064 for Special Temporal Authority on a Satellite Space Stations filing.

IBFS_SATSTA2001072400064_456894

Before The RECE'VED FEDERAL COMMUNICATIONS COMMISSION Washington, D.C. 20584 AUG 3 0 200; rom mumoroe Oretchewuen In the Matter of ) 1B DocketNo.95—91 ) XM Radio, Inc. Request for Special ) File No. SAT—STA—20010712—00063 Temporary Authority ) ) Sirius Satellite Radio, Inc. Request for ) File No:SAT—STA—20010724:00064 Special Temporary Authority j REPLY COMMENTS OF VERIZON WIRELESS SUMMARY Verizon Wireless hereby repliesto comments filed with the Commission in response to applications for Special Temporary Authority ("STA")filed by XM Radio Inc. (XM) and Sirius Satellite Radio Inc.(‘Siius") (the *Applications")." The Applications seek authority to operate high—power (above 2kW EIRP) terrestrial repeaters in the Digital Audio Radio Service ("DARS"). Verizon Wireless is opposed to the grant of the Applications. First,they fail o satisfy the relevant legal standard for an STA. Second, the proposed operations would severely impair Verizon Wireless® planned use of the adjacent Wireless Communications Service ("WCS") band for emerging broadband wireless access (*BWA") services." The Applications for STA should both be denied. ‘ XM Requestfor STA, Fil No. SAT—STA—20010712—00063 (iledJuly 12, 2001) @XM STA"Y;Sirus Requestfor STA,File No. SAT—STA—20010724—00064 (Red July 24, 2001)(‘Srus STA") * Verizon Wireless (biddingas PCSCO Parmership)paid S1.6 million for the A block WCS Hcenses in the Baston (MEON), New York (MEO2), Butalo (MEO3), PhiladeJphi (MBO4), Washington (MEOS), Richmond (MEOG) Pitsburgh (ME12), and Cincimati (ME3) Major Economic Areas

A. The STA Applications Fail To Make The Required Legal Showing, —And Should Be Denied. Congress established the legal standard by which the Commission must evaluate STA applications. Section 309(f) ofthe Communication Act of 1934, as amended ("the Act"), mandates that the Commission find that there are extrordinary circumstances requiring temporary operations in the public interest and that delayin the institution of such temporary operations would seriously prejudice the public interest."". Further, "grant [of] a temporary authorization, [must be} accompanied by a statement ofits reasons therefor...."" Such a finding, to avoid being arbitrary and capricious, must be well reasoned and based on evidence in the record. The Commission codified Section 309(f) in Section 25.120 ofts rules." The rule requires that applicants demonstrate that "circumstances requiring immediate or temporary use of facilitis" exist.® Purther, the application must contain "the full particulars ofthe proposed operation including all facts sufficient t justify the temporary authority sought and the public interest therein.*" The rule clarifies that only "upon a finding that there are extraordinary circumstances requiring temporary operations in the public interest and that delay" *would seriously prejudice the public interest"* will the Commission grant an STA. The rule specifically states thatits finding of extraordinary > arus.ca. 3 300001990 * ul * ancre 5251200 *m ! 1. * ud o g2s.1200)

circumstances cannot be based on "convenience to the applicant, such as marketing msidm\iong of meeting scheduled customer in—service dates."" As the initial comments demonstrate, here is no plausible basis for granting STAs to XM or Sirius.!* Neither comes close to mesting the legal standard. XM and Sirius do not describe the "full particulars" of their proposed terrestrialrepeater operations. While both applicants indicate that they intend to deploy low—power terrestrial repeaters operating below 2kW, neither has provided any information regarding these repeaters."" As AT&T Wireless notes, the Commission‘s rules do not permit the blanket authorization ofany terrestrial repeaters regardless ofpower levels."" Since any STA issued to XM or Sirius will obligate them to operate on a non—interference basis, WCS and other affected Hicensees must know the location and operational characteristics ofall proposed repeater deployments so that they can adequately assess how these repeaters will impact their existing and planned operations. XM and Sirius full o show that there are "extraordinary circumstances" present that would require grant ofthe Applications. In fact,neither Application makes any mention of "extraordinary circumstances".. Instead, the Applications make unsupported statements that grants would be in the "public interest." The current circumstances are anything but extrmordinary, First,as XM and Sirius acknowledge in their Applications, there is a pending rulemaking in which the Commission is considering rules governing *a "* See Comments of Mtricom, In. filein esponse to XM and Sirus STAs (*Mervicom Comments") (Bled Aupust21,2001) at see Comments of AT&T Wireless Services, In., Aled n response to XM and Sirs STAs (CAT&T Comment‘) (Rled August 21,2001) t 2; see Comments ofBellSouth Corportion, filed in responseto XM and Sirus STAs (‘BellSouth Commen") (Rled August 21,2001) at "‘ XM STA atp.2, n 4; Sirs STA atp.3, n. 9.

the use of satellite DARS terrestrial repeaters."" XM and Sitius failto show why that rulemaking is not the proper proceeding to address their use ofterrestrial repeaters and the technical requirements for such use. Their STA requests are an obvious attempt to circumvent the rulemaking. Second, the circumstances XM and Sirius find themselves subject to are of their own making. Specifically, XM states thatit "has been operating repeaters in these markets for several months pursuant to its nationwide experimental license and now seeks to use its repeaters to provide service to consumers.""" Sirius has been operating itsterrestrial repeaters since October 14, 1999 pursuant to an experimental license."" Now, XM and Sirius want to parlaythat experimental authority into commercial use. However,they fail to cite any Commission precedent that would support grants ofthese Applications in light of the factthat they have constructed facilities pursuantto experimental authorizations without regard for the ultimate resolution of the pending rulemaking. The FCC has previously wamed against just such attempts "to establish commercial businesses under the guise of experimental licenses.""* It should not allow XM and Sirius to do so here. As AT&T notes, grant ofthe STAs could have "a more widespread impact on the integrity and enforcement of the Commission‘s rules if it is " AT&T Comments at d * in the Matter ofEstablshment ofRules and Policiesfor the Digizel Audio SeteiteService in te 2310— 2360 MHs Frequency Band, 12 FCC Red 5754S610—5812 (1997) (Report and Order Memorandum Opinionand Order and Further Noticeaf Proposed Rulemaking) (‘DARS Proceeding"). " xn Staal ® Sinus STA ar2. " Amendment ofPart $ ofthe Commission‘s Rulesto Revise the ExperimentalRadio Service Regulations, 11 rco Red. 20130, 20136 (1990)

viewed as a ratification of an abuse of the Commission‘s experimental authorization regime.""" Further, XM makes a conclusory statement that "[gJrant of this STA will serve the public interest by ensuring that the public enjoys the full benefit of DARS at the earliest possible date."" Similarly, Sirius states that a grant *would serve the public interest by allowing Sirius imminently to initiate uniformly high quality commercial satellite DARS programming nationwide.""" As noted above, both the Act and the Commission‘s STA rule state that the Commission must find that "extraordinary circumstances" require temporary operations in the public interest and that delayofthe temporary operations would seriously prejudice the public interest. XM and Sirius "rest their claims of ‘extreordinary circumstances‘ on their desire to market and provide services to customers sooner rather than later.""" However, the Commission‘s rules explicily identify "marketing considerations"as a circumstance that is insufficient to justify an STA.*" Apart from these "marketing considerations,"neither Application provides any additional factual basis upon which the Commission could find that temporary operations pursuant to STAs are in the public interest and furtherthat delay of the STAs would seriously prejudice the public interest. " AT&T Comment at . " xn STAm2. * Sins STA at 1. * BellSouth Commentsat 13. 3 47 CR §2512000). seealsoIn the Matter ofApplications ofCOMSAT Corporation, Order, 13 ECC Red 319 (ntemational Bureau denied anapplication for STA whereapplicant argued that robust consumer demand, oupled withadvers effct ofapplican‘s iabilty to marketservices constituted emergency—like circurstancessatsfied requirement ofdemonstrting"extraordinary cicumstances.") 1 2,7.

XM and Siius bear the burden of demonstrating whya grant ofthe Applications is warranted. However, they have failed to provide the "full particulars" of their proposed repeater networks, failed to demonstrate the "extraordinary circumstances" that would justify an STA, and failed to demonstrate how a delay in the institution ofthese operations would "seriously prejudicethe publi interest." Accordingly, the Commission must deny the Applications for STA. B. The Use OF DARS Terrestrial Repeaters Will Cause Harmful Interference To WCS Operations. There is clear evidence in the record that the proposed deployments of terrestrial repeaters operating in the 2320—2345 MHz DARS band will severely impair the use of the adjacent 2305—2320 MHz and 2345—2360 MHz WCS bands by creating large exclusion zones within which WCS operators will be effectively precluded from providing service."" These exclusion zones are the result of two primary sources of interference — blanketing interference and intermodulation distortion. Blanketing Interference. This type of interference, sometimes referred to as "brute force overload", occurs when a very high power signal in one band overshelms Jower power signals in nearby bands, overloading the front end ofthe radio receivers in those bands. This phenomenon is well recognized, and the harmful effects of blanketing interference that would result rom the use ofhigh power DARS terrestrial repeaters has been clearly demonstrated in the DARS proceeding."" * AT&T Comments, Artichment B; BellSouth Comment, Atachment B. ®: Seegenerall Comments ofBellSouth Corporatio, (Med Feb, 22, 2000), in responseto Supplemental Comments ofXM RadioInc. and Srius Satelite Radio, DARS Proceedin, 1B Docket No95—91; see generaly Ex Pat Preseniation oAT&T Wircless Services, Ic, DARS Proceeding (Red Feb. 20, 2001).

The objections raised in the comments to the Applications should, therefore, come as no surpriseto the applicants or to the Commission. The analyses submitted by various commentators clearly show that the operation of high—power terrestrial repeaters as proposed by XM and Sirius will create large exclusion zones that will effectively preclude the provision of WCS."" In fact, the analysis submitted by BellSouth concludes that the effects of blanketing interference are significant even when DARS terrestrial repeaters are limited to 2 KW power levels."" Intermodulation Distortion. XM and Sitius intend to use spectrum in the 2324,25—2328.25 MHz and 2336.75—2340.75 MHz bands to deploy terrestrial repenters."" The frequency spacing between these two bands is such that the 3" order intermodulation products of the two repeater signals will land directly in the WCS band.2" This produces intermodulation distortion at the WCS receiver that would result in exclusion zones that are potentially much greater than those resulting from blanketing interference."" As a result, WCS operations will be restrcted in any market where both XM and Sitius deploy terrestrialrepeaters."". BellSouth notes that "the potential for intermodulation distortion from nearby DARS repeaters is tremendous" and that "this condition would apply to any DARS repeaters, whether they are high power or micro—repeaters [less than 2 kW}."@° * AT&T Comments, Atachment B; BellSouth Comments, Atachment B. * BellSouth Comments, Atachment A,4. * See Agreement Benveen the Government ofh Unied States ofAmerica and the Government ofthe United Mexican States Concerning the Use ofthe 2310—2360 Mz Band, (uly 24, 2000), t Appendix 1. "" See Comments of BeamiReach Networks,In., filed in response to XM and Sirius STAs (‘BeamReach Comment") (iled August21, 2001), at 5; BelSouth Commens, Artachment C,at10. " ReamReach Commentsat9 " Mas * BellSouth Comments, Atachment C t 9.

Interference Analysis. Verizon Wireless has conducted ts own assessment of the potential for blanketing interference and intermodulation distortion that would result from the operation ofDARS terrestrial repeaters. This analysis, included in the attached Appendix, was performed in conjunction with BeamReach Networks, Inc. — a company that has developed spectrally efficient Adaptive Mutibeam OFDM wireless technology for the provision of BWA services in the WCS band."" The analysis clearly demonstrates that the deployment ofhigh—power DARS terrestrial repeaters, as proposed by XM and Sirius, would result in significant harmful interference to WCS operations. Using the Atlanta market as an example, the analysis concludes that 29.6% ofthe market would be exeluded due to blanketing interference and 51.7% ofthe market would be excluded due to intermodulation distortion. The size of these exclusion zones would effectively preclude the offering of WCS in Atlanta. The analysis also demonstrates conclusively that the deployment of DARS terrestrial repeaters at power levels in excess of 2 KW is likely to create similarly large exclusion zones in other areas, and thus, preclude the offering of WCS in any market in which such repeaters are deployed. Moreover, the analysis demonstrates that the number ofterrestrialrepeaters deployed will impact the size of the exclusion zone even if the power levels of such repeaters are limited to 2 kW. For example, Case 2 in Table 1—1 illustrates how the exclusion zone resulting from intermodulation distortion would increase from 2.2% to 33.7% if the spacing between 2kW terrestrial repeaters were decreased from 8 km to 4 km. Based on this analysis, it can be concluded that the * Verizon Wirless is consideringthe deployment of BearReach equipment i ts WCS markets, and has planned a technicalra for thefist quantr of2002

potential for DARS terrestrial repeaters to cause harmful interference to WCS operations is affected by both the power levels of the repeaters and the number of repeaters deployed in each market. BeamReach has examined the technical feasibility and incremental costs associated with the use ofhigh—Q filters in the BWA receiver front—end to attenuate DARS emissions. Its analysis concludes that the cost ofincorporating such fiters into the CPE would be uneconomical. Moreover,it would be "insufficient to allow unlimited deployment of high—power repeaters and would therefore require considerable coordination efforts between WCS licensees and DARS operators.""" C The Commission Must Impose Limits On The Deployment Of DARS Terrestrial Repenters. Verizon Wireless and other WCS licensees purchased their licenses with the intent ofproviding service to the public. Bringing a newwireless service to the public requires muliple stages of development including network design, testing, and construction. Each stage of development requires a substantial investment of ime and financialresources. A key consideration in the decision to make any investments in WCS (or any other wireless service)is the certainty that the licensee will be protected from harmfulinterference. The Applications, if granted, will cause harmful interference to existing and future WCS operations and effectively preclude the offering ofbroadband wireless services in the WCS band."" "" DARS Terrestrial Repeater Analysi, discussed infro, Appendi, t 5 ee also Ex Pare Communications ofBeamiReach Networks,Inc., DARS Proceeding (Rled May 30, 2001) at3—6. ®.See Oppositonto STA Request of WorldCom, Ic. filed n responseto XM and Siris STAs (*WorldCom Oppositon‘) (Rled August 21, 2001) at2; AT&T Commens at 7.

10 ‘The Commission can avoid this undesirable outcome by establishing appropriate Hinie for the deplopment ofDARS tevestie! repesters in the pending rulemaking proceeding. The Commission routinely has adopted rules to limit the potential for harmful interference from one service to another."" It should do so here. We urge the Commission to adopt rules that would limit the power levels of all DARS terrestrial repeaters to 400 W/MHz (for a maximum of 2kW over a 5 MHz bandwidth). However, we do not agree with other WCS licensees that XM and Sitius should be permitted to deploy "as many terrestrial DARS repeaters operating at power levels up to 400 W/MHz as are necessry"."" As our analysis indicates, the deployment of a large number of2kW repeaters will also resultin significant blanketing interference. Thus, we also recommend the adoption offeld strength contours that would minimize the potential for large signal blockage caused by DARS repeaters. A practical imit would be —45dBm, in a resolution bandwidth of 1 MHz, for no more than 2% of the population at a reference height of25 feet in each coverage area The Commission should also adopt rules that require XM and Sirius to coordinate their terrestrial repeater deployments with each other to ensure that the overlapping field strength contours do not result in excessive intermodulation distortion, and thus, create large exclusion zones for WCS. We recommend the coordination offeld strength contours at 50 dBmy—80 dBm (or viceversa), 60 dBm—60 dBm, and —40dBmy—100 dBm (or viceversa) at a reference height of25 feet. * See 47 CFR. §§22.393, 73.73,318, and 73.685(d). Seealso Amendnent ofPor 73 ofthe Conmmission‘s Ruls o More Effctmely Resolve Broadcast Blonketing Intarference, 11 FCC Red. 4750 (1996)(rending NPRM). * mellSouth Comment at 32

11 concrusion Verizon Wireless urges the Commission to prompily deny the Applications because they failto satisfy the relevant legal standard for an STA and would effectively preclude the offering ofbroadband wireless services in the WCS band.. We also urge the Commission to quickly conclude its DARS Proceeding by adopting the power limits and other requirements described herein. Respectfully submitted, VERIZON WIRELESS ay_ 4e&—\ $@Kz John T. Scott, 1 Vice President and Deputy General Counsel — Regulatory Law Donald C. Brittingham Michael P. Samsock Verizon Wireless 1300 I Street, N.W., Suite 400W Washington, DC 20008 (202) 589—3740 Dated: August 30, 2001

cxnom DARS Terrestrial Repester Analysie Page1 Append DARS Terrestrial Repeater Analysis This report documents two independent analyses of blocking and intermodulation distortion (IMD) overload due to the proposed operation ofterrestrial repeaters in the 2.3 GHz Digital Audio Radio Service (DARS) band. The first is a generic analysis ofa typical urban/suburban coverage area. Within the coverage area, broadband wireless access (BWA) systems, deployed in the Wireless Communications Service (WCS) band, attempt to operate in the presence ofhigh power (greater than 2 kW at 5 MHz) terrestrial DARS repeaters. A significant number of houscholds were excluded from coverage due to blocking and IMD overload. In the second analysis,trepeater networks proposed by XM and Sirius in the city of Atlanta were analyzed using a terrain—based propagation tool. Once again, a significant number of houscholds were excluded from coverage due to blocking and IMD overioad. Generic Analysis of Blocking and IMD Overload of BWA Systems Due to DARS Terrestrial Repeater Operation This section analyzes potentialblocking and IMD overload to fixed, BWA systems operating in the same geographical region as terrestril repeaters proposed by XM and Sirius. This analysis assumes generic parameters emulating those of the XM and Sitius repeaters. The parameters of the BeamReach BWA customer premise equipment (CPE) were used for the victim receiver parameters. Two cellularized networks were analyzed, one with XM repeaters and the other with Sirius repeaters. Each has the following characteristics: * Each system uses a cellularized layout ofradius R using hexagonalcells. * The area of each cell is 2.6R accounting for the hexagonal area ofthe cell. * The radius is settable, with a nominal radius of 8 km emulating the Boston and Atlanta repeater layouts. 4 km cells were also analyzed. * Each system uses an average transmitter height of 60 m emulating the Boston deployment, and 120 m emulating the Atlanta deployment. * No additional transmitter height due toterrain was used, though this may be warranted. * Repeater EIRP was settable, and was evaluated at 2kW, 10 kW, and 20 kW. * XM Requesfor ST4, File No. SAT—STA—20010712—00063 (Rled July 12, 2001) (XM STA"; Sirus Requestfor STA, File No. SAT—STA2001—0724—00064 (Rled July 24, 2001) "Sirls STAY).

cesom DARS Terrestiat Repeat Anatysis Vage2 * The antenna pattems of the repeaters were omni—directional * The XM and Sirius repeaters were spacing R km apart. The cell centers of one network were coincident with the cell vertices (hexagonal grid) ofthe other network. * CPE were uniformly distributed within each cell * On average, each CPE is in close proximity to two repeaters per repeater cell, the XM repeater and the Sitius repeater. Each contributes to blocking, and each jointly contributes to IMD (additional repeater power from more distance repeaters is also significant). The following propagation model was used: * Propagation Model, Hata with COST 231 extension, suburban model * CPE antenna height 6 m, the reference height + BTS antenna height 30 m * Repeater antenna height 60 m emulating the Boston deployment, and 120 m emulating the Atlanta deployment + Log normal shadowing parameter, 8 dB standard deviation. Note that Ricean or Rayleigh fading was ignored. The impact ofthis type of fading is to increase slightly the exclusion zone margin, due to the composite Rayleigh/lognormal distribution for the mean receiver power levels. * 90% confidence exclusion zone" The following receiver characteristics were used for the CPE: * Pre—sclection filtering, 55 MHz passband, passes the A, B and CD bands simultancously. * TDD operation * 1.25 MHz processing and IF bandwidth * 5 dB noise figure The following 3" order non—linearity model was used for the CPE: + 2P4 + P; — 21P3 = Acceptable IMD Noise Floor (IMDys) + Po, P;are the power levels due to repeaters 0 and 1 respectively. * IMDiylevel set for an increase in the operational noise floor by 1 dB. * A 90% confidenceleveis typially used in mobile communications. n broadband fixed wirelss, confidence exclusion zones may exceed 95%, which would increasethsize ofhe exclusion zones.

cenom DARS Terrestrial Repester Anatysis Page3 + MDy=—113.9 dBm The following large signal—blocking model was used for the CPE: * Blocking signal level=—31 dBm conducted for COFDM signals with 10 dB peak to averageratio (filtered COFDM running at —3 dB backo!) * NFloormcawlevel set for an increase in the operational noise floor by 1 dB * NFloOmeawg =—13.9 dBm The following antena characteristies were used for the CPE: * 18 dBi gain * Vertical polarization * 36 degree beamwidth, sidelobe to sidelobe level + —13 dB sidelobe level,—10 dB sidelobe level after installation w/ coupling and local multipath. + Antennas arbitrarly pointed with respect to the repeaters, uniformly distributed in azimuth. + Pointed with 0 degrees up tilat the serving base station. Exclusion zones were computed for each repeater for the following repeater induced impairments: * Large signal blocking * Spurious Emission meeting 75 dB + 10log(P) emission mask * IMD blocking Results for Blocking and IMD Limiting Five analytic cases were computed, each determining an exclusion zone centered on each repeater due to blocking or IMD limiting*. The percentage of CPE excluded could then be computed. Table 1—1 summarizes the results. Four columns are shown in Table 1—1. The antenna coupling mechanism is listed in the second column. The third and fourth columns tabulate the percentage of CPE excluded by either blocking or IMD limiting. In these columns, separate numbers are given for ither sidelobe coupling or mainbeam * A more rigorous anlysisfo IMD limiting would require usof th probsbilty densit function of the 3" ordenon—linearity outputterm, 274 + P,—2IP..This wouldlead to larger exclusion zones than the ones preseted withth simpliied approach used in this paper

oxsom DARS Terrestriat Repester Anabyis Paged coupling. For the IMD limiting case, mainbeam coupling means that the stronger signal couples via the mainbeam and the weaker signal couples through the sidelobes. The 90%/10% blended results are shown in the rows designated "Mainbeamn/SL + Sidelobes" and is indicative of the expected level of exclusion for a broadly deployed BWA system. Table 1—1 Subscribers Excluded Due to Terrestrial Repeater Operation Antenna Coupling [remmmed | | REW, R=S km, Hir—60m _| Mainbeam/SL= Sidelobes $8% $2% Hepe=6m | Sidelobes Ont 29% 1.7% | Mainbeam/SL Only 11.7% 72% I 2KW, R=4 km, Htr60m Mainbeam/SL Sidelobes 152% paak Hepe=6m Sidelobes Only 17% 152% Mainbeam/SL Only |46.8% 100% 1 20kW, R=8 km, Hir=60m Mainbeam/BL + Sidelobes_| 152% Ba6t Hepe=6m Sidelobes Only |11.7% 152% Mainbeam/SL Onl |467% 100% | T0kW, R—§ km, Hr—120m MainbeamL x Sideiobes_| 195% Fos% Hepe= 6 m Sidelobes Ont 149% 26.0% | [ Mainbeam/SL Only 64.9% 100% 1 7 EW, R=4 km, Htr—60m MainbeamSL=t Sideiobes_| B4% eA 2x more BWA base stations Sidelobes Only 34% 2.1% Hbts=45 m Hepe=3 m Mainbeam/SL Only 13.5% £9% Case 1 is characterized by a maximum effective isotropic radiated power (EIRP) of2kW with a moderately high antenna height o60 meters. In this case, an acceptable level of blocking and IMD limiting is achieved. In Case 2, the cell radius is reduced to 4km and the blocking percentage increases to over 15% and IMD limiting jumps to almost 34% of the subscriber base. In Case 3, the transmitter power is increased to 20 KWwith the cell radius retumed to Skm. This case results in approximately the same performance. The blocking level increases to over 15% and the IMD limiting exceeds 33%. Case 4 reduces the EIRP to 10 kW and increases the transmitter height to 120 meters. This case approximates the proposed Atlanta deployment. The outage percentages increase further as shown. Cases 2,3, and 4 present unaceeptable business cases for the operator.

ceron1 DARS Terrestrial Repeater Analysis Pages Case 5 attempts to reduce the influence ofterrestrial repeater overload by reducing the CPE antenna height from 6 m to 3 m. This reduces the exclusion zones around the repeaters t the expense of doubling the number of BWA base stations and requiring that the BTS antenna heights be increased from 30 m to 45 m. Results for the Base Station The BeamReach base station incorporates very high Q cavity flters. These filters effectively attenuate terrestril repeater energy such that the exclusion zones are modest and limited by the emission levels of repeaters and not by blocking or IMD mechanisms. Base stations co—located with repeaters still need a minimum separation distance defined below. Note that the cost of eavity filters precludes their use in the CPE. Results for Emissions The emission levels proposed by XM and Sirius of 75 dB + 10log(P) generate an exclusion zone of 230 meters provided that the emissions can be treated as a uniform broadband energy in the WCS band. If the WCS 80 dB + 10log(P) rule were employed, the exclusion zone would be reduced to 130 meters. Additional CPE Filtering Costs to Attenuate DARS Emission We have examined the technical feasibility and incremental costs associated with high—Q filters in an attemptto attenuate DARS emissions. High performance BWA CPE, such as that from BeamReach, typically use a bandpass filter ahead of the Low Noise Amplifier (LNA) in the receive path. A subsequent SAW filter (after the LNA) is used to reduce unswanted in—band signals,such as adjacent WCS or DARS satellite or terrestrial repeater signals. Signal energy within the DARS band is not attenuated by the bandpass filter but is attenuated by the SAW fiters. The characteristies of such a low cost bandpass filter are shown below in Figure 1—1. This device represents a cost to the service provider of approximately $30 in high volumes. This receiver filtering design is based on the assumption that DARS Licensees may deploy terrestrial repeaters operating at a peak EIRP of up to 400 W/MHz, evenly distributed across the band (for a total of 2 kW per 5 MHz). This is the same emission limit to which the WCS licensees themselves are subject. The design also assumes that the out of band emissions generated by DARS terrestrial repeaters shall be limited to at least 75 + 10 log (p) dB (where p is the EIRP in watts) less than the trancmitter EIRP.

escomt DARS Terrestrial Repeater Analysis Pageo 1 tecentae revien isnn ms1 ies tremarems anaess on rmans in x Geinas io interrens‘ Innormowe feroencermeme en se miine Sam Figure 1—1; BeamReach CPE — Current Bandpass Fiter (Verical Markers intiare WCS sub—bands . B, C and D) As a result of XM and Sirius proposals to use high power terrestrial repeaters, BeamReach has investigated the feasibility and costs of additional front—end filtering for the CPE. Figure 1—2 below shows the frequency response of a 6—section pseudo—elliptic notch filter that could be added tothe receiver front—end circuitry. Using pricing from our filters vendors, this filter would increase the price of the CPE unit by $50 in high volumes (in excess of25% of the long term price objective). Ifthi filer were added, an increase in power amplifier cost would be necessary to overcome the additional filter loss and stll maintain the necessary system performance. This would add an additional $20 to the price of the CPE in high volume. This additional filter would partially attenuate the DARS interference, protecting the LNAffront—end from some ofthe harmfal compression that would otherwise be caused. However, this design would stll be insufficient to allow unlimited deployment of high power terrestrial repeaters and would therefore require considerable coordination efforts between WCS licensees and DARS operators. Moreover, the filter shown in Figure 1—2

c€ou1 DARS TerrestrialRepeaterAnalysis Page? severely attennates the C/D block. A higher order, higher costfilter would be necessary for these blocks. In summary, the incremental CPE cost o 70 for A and B block operators, which is 35% ofthe long term CPE price objective, is economically not feasible in this very price sensitive consumer application.. Incremental costs are even higher for C/D block operators. Fnsiaes fscerse t Secion ooo norc on ow o Intontom on as B s B e 3e s Te Fnowey tow) Figure 1—2; Simulated 6—section Band—refect Filter (Vertical Markers indicate WCS sub—bands A, B, C and D) Blocking and IMD Overioad Analysis in the Greater Atlanta Region This section analyzes potential blocking and IMD overload to fixed, BWA systems operating in the same geographical region as terrestrial repeaters proposed by XM and Sirius. XM and Sirius data was available for the Greater Atlanta region for this analysis. The parameters ofthe BeamReach BWA system were used for victim receivers. Two overlapping terrestral repeater networks were analyzed in the greater Atlanta region, one with XM repeaters and the other with Sirius repeaters. The coverage area of each network was determined using CommStudy, a terrain based propagation modeling tool. For each network, the proper location, EIRP, antenna pattemn, antenna pointing

c%001 DARS Terrestrial Repeater Analysls Page$ angle and anterna height were input according to Tables 2—1 and 2—2. This data was derived from the XM and Sirius STAs. The following methodology was used: CommStudy was used to evaluate field strength over the coverage area for the two networks. Field strength maps were computed in dBu for each network independently. Population overlay maps were used to assign the population into 12 field strength bins from 50 dBu to 105 dBu in 5 dB increments The number of users affected by large signal blocking was then determined for CPE that couple to the repeater through the sidelobe region of the antenna. In addition, the number ofusers blocked in the mainbeam region was also determined. The total number ofaffected users was determined by blending sidelobe and mainbeam blocked users in the ratio of 90% to 10%. This corresponds to the ratio of the CPE antenna sidelobe region to mainbeam region. The Longley Rice propagation model was used, using 50% confidence levels for all parameters. The reference height of CPE was used to determine field strength level. 5 dB was added to the Longley Rice field strength bins to produce the data for 90% confidence exclusion zones. In addition, the number of users affected by IMD signal limiting was then determined for CPE that couple to the repeater through the sidelobe region of the antenna. In addition, the number of users blocked in the mainbeam region was also determined. The total number of affected users was determined by blending sidelobe and mainbeam blocked users in h ratio of 90% to 10%.

cenom DARS TerrestrialRepeater Analysis Page Table 2—1. XM Repeater Data, Greater Atlanta Area 90 deg. 160 deg. 3444 120 deg. 180 de; 2486 90 deg. 180 deg. 12926 120 deg. 270 deg. 2396 360 deg. 0 deg 7204 120 deg. 135 deg. 3606 120 deg. 60 deg 2014 | 120 deg. 45 de 2634 120 deg. 300 deg. 3444 120 deg. 10 deg 2416 360 deg. 270 deg. 3444 6e Table 2—2. Sirius Repeater Date, Greater Atlanta Area Al Ts 180 deg. 0 deg Ad. To 180 deg. 180 deg: Ad.2 120 deg. 270 def Ad. 3a 090 deg. 30 de Ad. 3 090 deg. 150 deg. Ad. 4e 090 deg. 45 deg Ad. t 090 deg. 180 deg. Ad. Se 180 deg. 0 deg. Ad. 5 180 deg. 180 deg. Results Field strength maps for the XM and Sirius repeater networks are shown in Figure 2—1 and Figure 2—2 respectively.. We note that the coverage area is over 4572 square miles with a population of 1.17 million people, each having a signal strength of over 85 dBu. 31% of these have signal strengths ofover 95 dBu. The CommStudy propagation tool automatically computes the number of users within field strength bins shown in Figures 2—1 and 2—2. The population density map is shown in Figure 2—3 for reference.

canom1 DARS Terrestrial Repeater Analysis Page 10 5ie Say e t Cbc is ms un se un un on se un on wn k wk n mam Figure 2—1.—— Field Strength Map of Siius Repeaters in the Greater Atlanta Region

cesom DARS TerrestrialRepeater Analysis Page 11 Sady h31 Ofi Renc uie o un se ux ue onk se un h uk otk ma ow mam Figure 2—2 Field Strength of XM Repeaters in the Greater Atlanta Region

cenom DARS Terrestrial Repeater Analysi Page 12 w00 f me mx . mm Figure 2:3 Population Density ofthe Greater Atlanta Region

cenom DARS Terrestrial Repeater Analysis Page 13 Using the receiver parameters given in Section 1, the number ofsubscribers excluded from BWA is given in Table 2—3. While 29.6% of potential BWA subscribers are limited by strong signal blocking, IMD effects limit 51.7% of these subscribers. Four columns are shown in Table 2—3. The antenna coupling mechanism is lited in the second column. The third and fourth columns tabulate the population limited byeither blocking mechanisms or IMD limiting.. In these columns, separate numbers are given for either sidelobe coupling or mainbeam coupling. For the IMD limiting case, mainbeam coupling means that the stronger signal couples via the mainbeam and the weaker signal couples through the sidelobes. The 90%/10% blended results are shown in the rows designated "Mainbeam/SL + Sidelobes" and is indicative of the expected level of exclusion for a broadly deployed BWA system. Table 2.3 XM Repeater Data, Greater Atlanta Area eam/SL + Sidelobes Sidelobes Ont 90.058 216427 Mainbeam/SL Ont 7iooss 902,521 Mainbeam/S+ Sidelobes 94409 x Sidelobes Ont 133,208 248.747 Mainbeam/SL Only 7a5,0t0 957550 Toul Population Effecied | MambesmSD > Sidelobss Ees | Total Population > 85 dBu _| 1.169.449 1169449 Population Excluded r £7% Conclusion In summary, BeamReach Networks has undertaken an analysis of the DARS terrestrial repeater deployment proposed by XM Redio for the Atlanta market as part ofis STA application. This analysis concurs with comments previously submitted that DARS repeaters will cause blocking interference in the WCS band and that DARS transmissions mixing within WCS equipment will create 3rd order intermodulation products within the WCS band.* The analysis also shows that when both DARS licensees utlize terrestrial repeaters in the same market,the 3" order intermodulation products resulting from * See Writen Ex Pane Communications ofthe Wirless Communications Association Inteationl,In., (Aled Dec. 15, 2000) n he Mater ofEstalihmentofRules and Policiesfor he Digial Audio Redio ‘Service in the2310—230 MFrequency Band, 1B Docket No. 95—91, Notice ofProposed Rulemaking (‘DARS Proceeding")

cecom DARS Terrestrial Repeater Analysis Page 14 mixing of both DARS frequencies at the WCS receiver have an even greater impact than large signal blocking. This phenomenon will occur within a WCS receiver (such as BeamReach‘s) when the interfering DARS signals exceed — 60 dBm, resulting in exclusion zones much larger than previously noted within this Docket. The close proximity ofthese bands does not allow for economical fitering atthe CPE. As such, granting the DARS licensees‘ proposals to use high power terrestrialrepeaters would render WCS spectrum useless and eliminate the option of using the WCS band for competitive broadband services. This analysis ofthe proposed deployment of terrestrial repeaters in the DARS band concludes that the proposed deployment will severely cripple the use ofthe WCS band for emerging 2—way, fixed broadband services. The proposed terrestrial repeater deployments will have these negative effects on the BWA operators and their equipment suppliers: * A significant number of otherwise eligible customers will be unable to receive broadband services because BWA receivers will suffer either blocking and/or intermodulation distortion caused by high power, in—band signals. * Thus, the cost ofBWA base stations and backhaul equipment will be shared over a smaller number of subscribers increasing the pro—rate cost per subscriber. More extensive filtering will be needed increasing base station cost and the BWA cell radius will be reduced due to added noise. * Using the Atlanta metropolitan region as an example, over 50%ofthe coverage area of1.17 million people would lose BWA services if both XM and Sitius deployed the proposed repeaters. Extending this to other major markets, the entire WCS BWA business is in jeopardy. * While it is technically feasible to add fitering to remove undesirable repeater energy, it is cost prohibitive in the CPE. High cost, high Q filter designs are needed to suppress DARS repeater energy only 13 MHz away. * The unfortunate frequency spacing between XM and Sirius repeaters ensures that 3" order intermodulation products between these two signals, will land directly in the WCS A, B and C/D blocks. * CPE installation will become more time—consuming and costly due to complex antenna alignment procedures that jointly optimize the signal strength ofthe desired signals while trying to achieve acceptable interference/ IMD levels from the proposed repeaters.

cxou DARS Terrestral Repeater Analysis Page 15 Recommendations Specifically, with respect to the terrestrial repeater rules, the Commission should limit emissions to no more than 400 watts/MHz with a maximum of 2,000 watts. We note that even with 2,000—watt ransmission, deployment on high towers and/or deployments with a cell radius less than 8 km will likely result in significant IMD overioad. Accordingly, field strength contours must be coordinated between XM and Sirius. These contours should be ~50 dBm—80 dBm, —60 dBm/—60 dBm, and —40 dBm/— 100 dBm at reference height of the 25 feet to limit the outage experienced by WCS operators. DARS operators may want to consider horizontal polarization for DARS terrestril repeaters. In this case, the above contours could be relaxed by 10 dB accounting for the cross—polarization rejection of vertical CPE anternas. The Commission should limit out—of—band emissions to 80 dB + 10log(P) in concert with the rules that WCS operators must follow with respect to the DARS band. Finally, the Commission should adopt field strength contours which limit large signal blocking caused by terrestrial repeaters. A practical limit would be—45 dBm for no more that 2% of the population at reference height ofthe 25 feet in each coverage area.

— Cel eate of Service 1 hereby certify that on this 30® day of August copies of the foregoing "Reply Comments ofVerizon Wireless" in Applications ofXM Radio, Inc. (SAT—STA—20010712—00063) and Sirius Satellte Radio, Inc. (SAT—STA—20010724—00064) for Special Temporary Authority were sent by first class mail or hand delivery (*)to the following parties: *Ms. Magalie Roman Salas * Mr. Peter Tenhuls, Sr. Legal Advisor Secretary Office of the Chairman Federal Communications Commission Federal Communications Commission 445 12" Street, SW 445 12° Street, SW — Room 8—B201 Washington, DC 20554 Washington, DC 20554 *Mr. Donald Abelson, Chief *Mr. Adam D. Krinsky, Legal Advisor International Bureau Office of Commissioner Tristani Federal Communications Commission Federal Communications Commission 445 12° Street, SW — Room 6—C750 445 12Street, SW — Room 8—B115 Washington, DC 20554 Washington, DC 20554 * Ms. Jennifer Gilsenan * Mr. Bryan Tremont, Sr. Legal Advisor Interational Bureau Office of Commissioner Abemathy Federal Communications Commission Federal Communications Commission 445 12" Street, SW — Room 6—A520 445 12" Street, SW — Room §—A204 Washington, DC 20554 Washington, DC 20554 * Mr. Chris Murphy *Mr. Paul Margic, Legal Advisor International Bureau Office of Commissioner Copps Federal Communications Commission Federal Communications Commission 445 12" Street, SW — Room 6—C437 445 12" Street, SW — Room §—A302 Washington, DC 20554 Washington, DC 20554 * Mr. Ron Repasi *Ms. Monica Shah Dessi International Bureau Office ofCommissioner Martin Federal Communications Commission Federal Communications Commission 445 12" Street, SW — Room 6—A505 445 12" Street, SW Washington, DC 20554 Washington, DC 20554 * Ms. Rosalee Chiara, Deputy Chief * Thomas J. Sugrue, Chief Satellte Policy Branch Wircless Telecommunications Bureau Satelite and Radiocommunication Div. Federal Communications Commission International Bureau 445 12" Street, SW — Room 3—C252 Federal Communications Commission Washington, DC 20554 445 12" Street, SW — Room 6—A521 Washington, DC 20554

* Mr. David Furth, Sr. Legal Advisor Mr. Bruce D. Jacobs Wireless Telecommunications Bureau Shaw Pittman LLP Federal Communications Commission 2300 N Street, NW 445 12° Street, SW, Room 3—C252 Washington, DC 20037—1128 Washington, DC 20554 Counsel for XM Radio, Inc. * Mr. Ron Netro, Sr. Engineer Mr. Carl R. Frank Policy Division Wiley, Rein & Fielding LLP Wireless Telecommunications Bureau 1776 K Street, NW Federal Communications Commission Washington, DC 20006 445 12" Street, SW, Room 3—C163 Counsel for Sirius Satellite Radio, Inc. Washington, DC 20554 Mr. William Wiltshire * Mr. Bruce France, Acting Chief Harris, Wiltshire & Grannis LLP Office of Engineering and Technology 1200 18" Street, NW, 12® Floor Federal Communications Commission Washington, DC 20036 445 12" Street, SW, Room 7—C153 Counsel for AT&T Wireless Washington, DC 20554 Mr. Douglas 1. Brandon *Mr. Julius Knapp, Deputy Chief Vice President — Federal Affairs Office of Engineering and Technology AT&T Wireless Federal Communications Commission 1150 Connectiout Ave, NW, 4" Floor 445 12° Street, SW Washington, DC 20036 Washington, DC 20554 Mr. James G. Harralson *M. Jim Burtle, Chief Mr. Charles P. Featherstun Experimental Licensing Branch BellSouth Corporation Electromagnetic Compatibility Div. BellSouth Wireless Cable, Inc. Office of Engineering and Technology 1155 Peachtree Street, NE, Ste. 1800 Federal Communications Commission Atlanta, GA 30309 445 12"Street, SW, Room 7—A267 Washington, DC 20554 Mr. Paul Sinderbrand Wilkinson, Barker, Knauer & Quinn LLP *Dr. Robert M. Pepper, Chief 2300 N Street Office ofPlans and Policy Washington, DC 20037 Federal Communications Commission Counsel for WCA 445 12" Street, SW, Room 7—C347 Washington, DC 20554 Mr. Mary O‘Connor Assistant Vice President *Ms. Jane Mago Spectrum Counsel & Regulatory Liaison General Counsel WorldCom Broadband Solutions Federal Communications Commission 8521 Leesburg Pike, Room 708E 445 12" Street, SW, Room $—C723 Viems, VA 22182 Washington, DC 20554

Mr. Robert Kappel Vice President Wircless Regulatory Affairs WorldCom, Inc. 1133 19° Street, NW Washington, DC 20036 Mr. Mike Hamea Director Regulatory & Govenmental Affairs Metricom, Inc. 1828 I Street, NW, Ste, 400 Washington, DC 20006 Mr. Rendall Schwantz Director Regulatory and Standards BeamReach Networks, Inc. 755 North Mathilda Avenue Sunnyvale, CA 94085


Document Created: 2005-09-28 15:35:09
Document Modified: 2005-09-28 15:35:09
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