VIA May 6, 2005

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VIA E-MAIL May 6, 2005 dgse-uwb@ic.gc.ca Mr. R. W.

of Wireless Systems Using Ultra-wideband Technology Dear Sir, The North American Broadcasters Association (NABA) is an association of North American Broadcasters in Canada, Mexico, and the United

1 VIA May 6, 2005 Mr. R. W. McCaughern Director General Spectrum Engineering Branch Industry Canada 300 Slater Street Ottawa, Ontario K1A 0C8 Canada Re: Gazette Notice Number SMSE Consultation Paper on the Introduction of Wireless Systems Using Ultra-wideband Technology Dear Sir, The North American Broadcasters Association (NABA) is an association of North American Broadcasters in Canada, Mexico, and the United States, and the NABA Technical Committee (NABA-TC) is its standing technical body. NABA is thus in a position to present the technical viewpoints of the most authoritative association of professional North American Broadcasters in television and sound programme production, post production, and distribution for terrestrial, satellite, and cable broadcasting. NABA is a Sector Member of ITU-R and a long-time participant in ITU-R Study Groups, Working Parties, Task Groups, Rapporteur Groups, etc. NABA numbers among its members Chairmen, Vice-Chairmen and members of the above groups. NABA also participates widely in the ITU work on radio, television and multimedia services and has a strong interest in studies including communications systems and distribution links. Full Members: CBC/Radio-Canada CBS Broadcasting Inc. Corporation for Public Broadcasting (CPB)/ National Public Radio (NPR)/Public Broadcasting System (PBS) DirecTV, Inc. Fox Broadcasting Company Grupo Televisa S.A. NBC Universal Time Warner Inc. TV Azteca S.A. de C.V. Associate Members: Bell ExpressVu Canadian Association of Broadcasters (CAB) Microsoft Corporation National Association of Broadcasters (NAB) Sirius Satellite Radio

2 INTRODUCTION: In this context, NABA has been studying the Ultra Wide Band (UWB) developments and participating in the work of TG 1/8 for some years. NABA continues to express serious concerns regarding the emission levels for UWB devices operating or emitting in the frequency bands allocated to the broadcasting services at VHF, UHF, and SHF. In short, NABA is concerned with the potential unregulated use of indoor, mobile, and hand-held UWB systems that can cause interference to all licensed broadcast systems. Moreover, since these portable, hand-held UWB devices will cross all borders and will be purchased internationally and delivered directly or by mail to consumers in many parts of the World, it is critical that international coordination ensures that appropriate noninterfering UWB power levels are respected worldwide. Thus, NABA s interest in the UWB issues of compatibility for Ultra-Wide Devices operating within the VHF, UHF, and SHF bands allocated to broadcasting services is apparent, and NABA welcomes the opportunity to contribute to the work of Industry Canada in establishing a regulatory structure that will ensure that the new UWB technologies and services will be compatible with the existing licensed radiocommunications services that are so vital to the North American public. THE ISSUES: The introduction of ultra-wideband (UWB) technologies offers new opportunities for short-range communications that will benefit many applications. It is likely that the introduction of UWB devices will bring about mass usage in various environments where licensed radiocommunication services in the VHF, UHF, and SHF bands are already deployed and are in operation. These existing services include radio and television broadcasting as well as broadcast auxiliary services such as wireless microphones, cameras, and site communications. These auxiliary services are frequently used during major events of interest to the general population including public crises, newsgathering and sports. In addition, mobile public safety radiocommunications utilize both the VHF and UHF bands. Broadcast services provide a range of communication services to both the commercial and governmental sectors. In the commercial sector, broadcast services provide communication to large areas and populations and are a vehicle for the rapid dissemination of information to the public. Such information includes communication of news and instructions to the public before, during and after emergency situations. In the government sector, the bands are critical for disaster planning and recovery and help to minimize further loss to human life and property. These bands provide critical communication between various national and local governmental agencies, including law enforcement, air traffic and control services, forestry services, and border patrol. 2

3 Accordingly, the need for protection of broadcasting services and mobile radiocommunications from any unacceptable levels of interference that may result from the operation of UWB devices should be recognized. Broadcast and mobile radio services are expected to operate to the limits of their sensitivity and without an established link margin. The situation is exacerbated further by the need for indoor reception in urban areas where UWB devices would be more prevalent and in closer proximity to broadcast receivers. Indoor broadcast receivers operate at their threshold such that any degradation will impact the availability of radiocommunications in the VHF and UHF bands. Techniques to minimize the interference impact of broadcast and radiocommunication services must be incorporated in UWB devices. Ultra-wideband devices, by their very nature, have emissions that intentionally extend across numerous frequency bands. The UWB emissions appear as an elevated noise floor within these bands. As the Satellite Industry Association comments point out the use of harmful interference as the benchmark for setting power limitations on UWB devices is not acceptable. In many cases, the allocation of broadcast services is based upon thermal noise-limited receive threshold. Since it will be difficult for UWB devices to avoid frequency bands allocated to broadcast and public safety services it is essential that the UWB power within these bands be limited. Specifically, NABA recommends that the UWB power spectral density in the broadcast channels be set below the design criteria used to establish broadcast channel allocations at the limits of coverage. POWER LIMITATION OF UWB DEVICES: Digital Television NABA is concerned regarding the emission levels promulgated by the United States Federal Communications Commission (FCC) for UWB devices operating or emitting in the frequency bands and (Low VHF), (High VHF), and (UHF), which are allocated for Broadcast s (BS) and, in particular, digital television (DTV). We are concerned with the potential unregulated use of indoor communication and hand-held UWB systems, which will cause interference to DTV at the specified FCC Part 15 emission limits 1. Table 1 illustrates that the UWB field strength emission limits are significantly higher (5 to 10.5 db) than the minimum DTV field strength required by the Canadian DTV Considerations and Allocation Principles 2,3. 1 U.S. Code of Federal Regulations, 47CFR15.209, Radiated emission limits, general requirements. 2 Digital Television Considerations and Allotment Principles, Joint Technical Committee on Advanced Broadcasting (JTCAB), Report AHG_ADD003K, May 26, Application Procedures and Rules for Digital Television (DTV) Undertakings, Industry Canada, Broadcasting Procedures and Rules, Part 7, Issue 2, July

4 Table 1 - Comparison of UWB emission limits in the TV Bands with the minimum required DTV field strength used for the final Canadian DTV allotment planning in dbµv/m. Low VHF High VHF UHF Part 15 UWB field strength emission limits Minimum required DTV field strength NABA is particularly concerned for indoor DTV reception in urban environments where UWB communication devices will most likely be deployed. Unlike analog television that will degrade gracefully, DTV reception is characterized by the cliff effect. As the noise from UWB devices increases, DTV will experience a sudden and catastrophic loss of reception. DTV receivers are expected to operate at near the thermal noise limit especially for indoor and fringe environments. The Advanced Television Systems Committee in its Receiver Performance Guidelines 4 expects a DTV receiver to operate at a signal level of 91 dbm/. Consequently, an UWB device must restrict its emissions below this limit throughout the DTV bands. Satellite Digital Audio Radio s NABA expresses its concern regarding the emission levels promulgated by the FCC for UWB devices operating or emitting in the frequency bands , and , which are allocated for Satellite Digital Audio Radio s (SDARS) operations. In particular, we are concerned with the potential unregulated use of indoor communication and hand-held UWB systems which cause interference to SDARS systems at the specified FCC out-of-band emission levels of 51.3 dbm/ and 61.3 dbm/ respectively with 3 meters separation. Our analyses, based on average power density emission and a single UWB device in response to the FCC specifications, clearly indicate that SDARS receiving systems signal to total noise power requirements will experience significant interference from the unregulated use of the fore mentioned UWB systems at the existing FCC emission limits. It is our belief that SDARS systems, which currently have several million receivers operating globally, will be severely compromised by the interference emissions of UWB devices especially communications and hand-held peer-to-peer systems. NABA recommends that the emission limits in Table 2 be adopted for UWB devices in order to ensure compatible operation between UWB devices and satellite broadcasting service in the bands , and ATSC Recommended Practice: Receiver Performance Guidelines, Advanced Television Systems Committee, Document A/74, 18 June

5 Table 2 Recommended UWB emission limits (dbm/) at a 3-meter separation Indoor Handheld Surveillance NABA also recommends that an emission mask for UWB devices be adopted in order to ensure compatible operation between UWB devices and satellite broadcasting service in the bands , and Such an emission mask should be capable of being met by all UWB device emissions so that compliance is guaranteed. Satellite C-band FSS Television and Radio s NABA is also concerned about the current US FCC regulatory power spectral density limit for UWB communications operation in the GHz band used for television and radio contribution and distribution. The potential for harmful aggregate interference depends on the number of UWB devices near a C-band Earth station receiver and on the elevation angle of the receiver. FSS receivers will experience complete reception failure at currently FCC regulated UWB power levels assuming emitter densities currently found in the environment of common wireless-based consumer items. For example, a 5 o C-band receiver elevation angle with an UWB density of 60 UWB devices per-acre, the UWB PSD limit would need to be adjusted from the US level -19 db to dbm/. The PSD limit would then be adjusted to -15, -11, -9, and -8 db for elevation angles 7.5 o, 10 o, 12.5 o, and 15 o, respectively. Moreover, the lower elevation angles are more likely to be encountered in Canadian and Alaska State C-band receivers and therefore they will be more susceptible to harmful aggregate UWB interference. Further, since UWB technology is expected to be implemented in both indoor and mobile hand-held devices, the outdoor use may be as likely, if not more likely, to cause harmful interference than the indoor devices. Even indoor devices have a great potential for causing harmful interference to a C-band Earth station receiver. C-band satellite receivers are often positioned on platforms at or near ground level in close proximity to surrounding high-rise buildings. In these cases, high-density indoor UWB devices operating in such apartment or office buildings, positioned above a satellite receiver only a few degrees off bore-sight can cause total failure of the C-band reception. In short, C- band FSS television and radio services are very likely to encounter frequent and severe interference from UWD devices operating with FCC authorized power levels. Broadcast Auxiliary s In addition to radio and television broadcast services, the broadcast auxiliary services (BAS) such as wireless microphones, cameras, and site communications are critical. These auxiliary services are frequently used during major events of interest to the general 5

6 population including public crises, newsgathering and sports. Table 3 illustrates the frequencies and applications for BAS. NABA recommends that the total interference from UWB devices to systems operating in the BAS frequency bands be limited such that the interference not exceed 1% of the total thermal noise at all times. Table 3 Frequency bands for Broadcast Auxiliary s (BAS) that are potentially susceptible to interference from Ultra Wide-Band devices. /Application Frequency Comments Bands Broadcasting/ Auxiliary Remote pickup (RPU) stations Broadcasting/ Auxiliary Remote pickup (RPU) stations Broadcasting/ Auxiliary ; Remote pickup (RPU) stations Fixed or Mobile/ Broadcasting Auxiliary Aural BAS, Studio to Transmitter Links (STL), Intercity Relay Fixed, Mobile, or Mobile Satellite/Broadcasting ENG Fixed or Mobile/ Broadcasting ENG Fixed or Mobile Primary point-to-point links 12,700-13,250 Primary point-to-point links shared with Cable TV Relay Broadcasting Satellite 17,700-19,700 19,300-19,700 38,600-39,500 Stations (CARS) Primary point-to-point links; Aural BAS, Studio to Transmitter Links (STL), Intercity Relay 6

7 INTERNATIONAL COORDINATION & GLOBAL HARMONIZATION: The transportable nature of UWB devices such as wireless computers, hand held devices, etc. means that millions of units can and will travel across borders, be purchased on the Internet and sent by mail to any country. Thus, appropriate power levels need to be internationally coordinated and globally harmonized. Otherwise a country with high UWB power authorizations can produce, sell, and ship such devices to countries with lower power limits and cause severe interference to licensed radiocommunications services in those countries where the high power levels are not approved. In such cases, after-the-fact interference corrections are virtually impossible to achieve. NABA believes that effective power level and interference criteria must be coordinated internationally and globally harmonized to prevent wide trans-border UWB power differentials to exist. CONCLUSION: UWB power levels must be structured such that they do not result in significant interference to any of the VHF, UHF, and SHF bands. The concept of not causing harmful interference as specified in the Radio Regulations Article 4.4 is not an appropriate target point. NABA notes that the ITU-R Study Group 6 on Broadcasting in its April 2005 Liaison Statement to Study Group 1 and TG 1/8 specified protection from interference to the broadcasting-satellite service (BSS) from emissions of devices without a corresponding frequency allocation in the Radio Regulations that produce fundamental emissions in the BSS Bands as a total interference that should not exceed 1% of the total system noise at all times. Furthermore, Study Group 6 also extended, on a provisional basis, the above criterion to all the remaining broadcasting service frequency bands. Therefore, when the total interference is normally not expressed in terms of total system noise, it should not increase the minimum field strength of more than 1%. Study Group 6 requested that such criterion be properly reflected in all the relevant documents produced by Task Group 1/8. As Industry Canada conducts its critical UWB studies, NABA will be very pleased to aid in the process in any way desired. Respectfully submitted, Carol Darling Executive Director On behalf of the North American Broadcasters Association, Rm. 6C300, 205 Wellington Street West, P.O. Box 500, Station A, Toronto, Ontario, M5V 3G7, Canada 7

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