July 2005 James Gilb, SiBEAM, Incorporated Slide 1 doc.: IEEE /0400r0 Submission Project: IEEE P Working Group for Wireless Personal Area Networks Submission Title: [Comments on WCA Petition to Change FCC Regulations Governing the Unlicensed 57 – 64 GHz Band] Date Submitted: [July 2005] Source: [James Gilb] Company [SiBEAM, Inc.] Address [39300 Civic Center Drive, Fremont, CA 94538] Voice: [(510) ], [first initial last name at sibeam dot com] Re: [WCA Petition RM Filed with FCC, September 2004; and a presentation by Gregg Levin to IEEE c, dated July 14, 2005] Abstract: [The WCA has proposed a change in the regulations that govern the use of the unlicensed 57 – 64 GHz band; the changes would dramatically increase the power injected into this band, thus increasing interference for low-power WPAN systems. There are good arguments to oppose the WCA proposal, and this presentation advances those arguments.] Purpose: [Contribution to TG3c at July 2005 meeting in San Francisco, California] Notice: This document has been prepared to assist the IEEE P It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P

July 2005 James Gilb, SiBEAM, Incorporated Slide 2 doc.: IEEE /0400r0 Submission Objectives  Comments on WCA petition of September 30, 2004, on 57 – 64 GHz rulemaking  Maintenance of current FCC protections and regulations in 57 – 64 GHz license-exempt band  Seeking cTG support in opposing WCA petition

July 2005 James Gilb, SiBEAM, Incorporated Slide 3 doc.: IEEE /0400r0 Submission Why is there interest in 60 GHz Band?  License – exempt operation in 57 – 64 GHz band  Very high data rates possible  Small form factors  Low – cost systems derived from low – cost electronics  Short – range wireless LAN and wireless data delivery products

July 2005 James Gilb, SiBEAM, Incorporated Slide 4 doc.: IEEE /0400r0 Submission Current 60 GHz rules  License-free operation under Part  Rules designed around wireless LAN usage 10 W EIRP10 W EIRP 500 mW peak power limit – (e)500 mW peak power limit – (e) 3-meter power density limits – (b)(1)3-meter power density limits – (b)(1) 9  W/cm 2 average9  W/cm 2 average 18  W/cm 2 peak18  W/cm 2 peak Transmitter IDs for access point coordination – (i)Transmitter IDs for access point coordination – (i)

July 2005 James Gilb, SiBEAM, Incorporated Slide 5 doc.: IEEE /0400r0 Submission Background of WCA Petition  Insertion of high – power point-to-point transmitters into the 57 – 64 GHz unlicensed band  Properties of proposed transmitters similar to those recently approved for fee-bearing, coordinated service at GHz, 81 – 86 GHz, and licensed service at 92 – 95 GHz (WT Docket No. 02 – 146; RM – 10288; FCC 03 – 248)  Rules for access to these 13 GHz are tailor-made for point-to-point links

July 2005 James Gilb, SiBEAM, Incorporated Slide 6 doc.: IEEE /0400r0 Submission Elements of WCA Petition  Specification of Transmitters using EIRP instead of Power Density  Request for a large increase in EIRP limits for unlicensed 57 – 64 GHz transmitters  Request for exemption for “window – mounted” point-to-point links from call sign requirement

July 2005 James Gilb, SiBEAM, Incorporated Slide 7 doc.: IEEE /0400r0 Submission Change from PD to EIRP 1.For historical reasons, many Radio Regulations written in units of Power Density at 3 meters 2.9  W/cm 2, measured at 3 meters, is equivalent to saying EIRP = 10 W 3.Changing to EIRP would need to be done throughout all parts of Radio Regulations 4.Changing from PD to EIRP need not be done “to ensure compliance with... Section (b)(1)... in the near field.” 5.In fact, Sec states that Part 15 equipment >30 MHz must be measured in the far field.

July 2005 James Gilb, SiBEAM, Incorporated Slide 8 doc.: IEEE /0400r0 Submission Change from PD to EIRP (cont’d.) 7. PD measurements only make sense in the far field (FF). 8. Current regulations specify PD measurements at 3 m. 9. For high-gain systems with FF > 3 m, 9  W/cm 2 at 3 m can be extrapolated to 2.2  W/cm 2 at 6 m, 1  W/cm 2 at 9 m, and so on. 10. Except for the virtue of clarity, there is no good reason to make this change.

July 2005 James Gilb, SiBEAM, Incorporated Slide 9 doc.: IEEE /0400r0 Submission Request for Increase in Power Limits 1.WCA has asked for increase in EIRP limits from 40 dBm (10 W) to “82 dBm less 2 dB for every dB that antenna gain is below 51 dB.” 2.This could result in an increase in antenna gain and transmitter power, up to an EIRP of 63,000 Watts! Antenna Gain EIRP Limit Transmitter Power 30 dBi 40 dBm (10 W) 10 dBm 40 dBi 60 dBm (1000 W) 20 dBm 51 dBi 78 dBm (63,000 W) 27 dBm

July 2005 James Gilb, SiBEAM, Incorporated Slide 10 doc.: IEEE /0400r0 Submission Request for Increase in Power Limits 1.What are the benefits? An increase in range. How much? 2.Estimates are that, for most US cities, range approximately doubles in all cases (see Appendix A) 3.But so does the interference range!

July 2005 James Gilb, SiBEAM, Incorporated Slide 11 doc.: IEEE /0400r0 Submission Appendix A: Sample Range Calculations for Outdoor Links 3 City Range with 10 W EIRP Range with 1000 W EIRP 1 San Diego 400 m 915 m New York City 308 m 645 m New Orleans 260 m 522 m Interference Range (all cities) m 2200 m 1.Taking rainfall data into consideration. Assumed receiver sensitivity of -90 dBm, consistent with a 5 dB NF and 1.25 GHz bandwidth, Rx antenna gain of 32 dBi, 20 dB SNR requirement, and 5 nines availability. 2.Interference range calculated for dry air, assuming that a competing signal 20 dB below the Rx sensitivity could cause interference. 3.Reference: FCC filing, dated November 29, 2004 by Rory Van Tuyl.

July 2005 James Gilb, SiBEAM, Incorporated Slide 12 doc.: IEEE /0400r0 Submission Interference Potential for Indoor Links Antenna Gain (G A ) Proposed EIRP Limit (P T ) Assumed Loss for Reflections 1 (L R ) Equivalent Path Loss 2 (PL) Equivalent Distance Ratio 3 (L eq ) 30 dBi 40 dBm 0 dB 0 (10 meters) 40 dBi 60 dBm 10 dB 9.6 dB 3 (30 meters) 50 dBi 80 dBm 10 dB 27 dB 21 (210 meters) 5 1.Assume interior losses from reflections of 10 dB, except for case of G A = 30 dBi. 2.Equivalent Path Loss = PL = P T – 40 dBm – L R 3.Equivalent Distance Ratio L eq = distance interfering high-power transmitter must be from WPAN Rx to effect same power as intended WPAN Tx 4.For all cases, assume WPAN transmits at limit of 40 dBm EIRP. Oxygen absorption included at 15 dbm/km 5. Point-to-point link must be > 200 meters away to interfere with only the same signal power as the intended WPAN transmitter! << < 10 meters (typ.) L eq Interfering high-power Tx Intended Tx (40 dBm EIRP) Rx WPAN System

July 2005 James Gilb, SiBEAM, Incorporated Slide 13 doc.: IEEE /0400r0 Submission Interference Potential for Indoor Links (cont’d.) EIRP (interfering Tx) Path Loss (PL) Equivalent Distance from Interfering Radiator (R)* 40 dBm 122 dB 547 m 60 dBm 130 dB ~1.3 km 80 dBm 135 dB ~2.3 km Assumptions: 1 GHz of signal bandwidth Noise figure of receiver = 8 dB Antenna gain of receive = 15 dBi Comparison of interfering high-power signal with thermal channel noise R = (PL) -1/2 /4  * * Distance interfering radiator must be away from intended receiver to effect noise equivalent to thermal channel noise Oxygen absorption included at 15 dB/km.

July 2005 James Gilb, SiBEAM, Incorporated Slide 14 doc.: IEEE /0400r0 Submission 1.The nearby 71 – 76 GHz band actually offers greater range (lack of oxygen absorption). 2.This band also allows operation with EIRP up to 55 W 3.Therefore, we recommend that The Commission make no changes to the existing EIRP for the 57 – 64 GHz band. Request for Increase in Power Limits

July 2005 James Gilb, SiBEAM, Incorporated Slide 15 doc.: IEEE /0400r0 Submission Request for Exemption to Call Sign Requirement  The WCA argues in favor of “window links” with high EIRP.  There is great potential for interference on both the receiving side as well as the transmitting side.  Window glass can reflect significant amounts of incident radiated power (see Appendix B).  Conservatively, an outgoing beam could scatter back into a room a signal only 10 dB weaker than the transmitted beam.  The combination of ultra-high power and lack of call sign sets the stage for high indoor interference.  We recommend continuation of moderate power levels and a publicly-declared call sign.

July 2005 James Gilb, SiBEAM, Incorporated Slide 16 doc.: IEEE /0400r0 Submission Appendix B: Window Reflections 1. ＜ January. 200 ４ > Doc. ： IEEE / mmwi,   Representative measurements of reflections off normal glass 1 Complex Permittivity 2  These values are reasonably uniform over various kinds of glass 2. ＜ March. 200 ４ > Doc. ： IEEE /0094r0-mmwi Akira Akeyama, NTT-AT

July 2005 James Gilb, SiBEAM, Incorporated Slide 17 doc.: IEEE /0400r0 Submission Reflectivity with and without Window Shades Ref: Sato, et. al., “Measurements of Reflection and Transmission Characteristics of Interior Structures of Office Building in the 60-GHz Band,” IEEE Trans. on Antennas and Propagations, Vol. 45, No. 12, Dec. 1997, pp –  Conclusion: ~10% reflectivity is a good (and optimistic!) approximation under a variety of conditions

July 2005 James Gilb, SiBEAM, Incorporated Slide 18 doc.: IEEE /0400r0 Submission 1. 1.Market for an IEEE standard-based consumer product (WPAN) will be considerably larger than that for outdoor point-to-point equipment. Efforts by IEEE to develop a standard attest to this market potential WCA objections to limited link distances at 60 GHz can be addressed with the FCC’s opening of the 70 GHz and 80 GHz bands Hence, WCA should consider moving to these bands to capitalize on more than 10 GHz of aggregated bandwidth and longer link distances than at 60 GHz WCA claims that the proposed rule change will not cause significant potential for interference are problematic On the contrary: at the power levels requested, links mounted indoors would exhibit significant interference, both by direct transmission and by reflected radiation from windows. Elements of Letter* in Circulation * IEEE P /0308r0

July 2005 James Gilb, SiBEAM, Incorporated Slide 19 doc.: IEEE /0400r0 Submission Request for Support of P /0308r0  We request an endorsement of this letter and that it be sent to the FCC.  Thank you!