State of International UWB Regulations in ITU - IEEE Presentation

1. Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [State of International UWB Regulations in ITU] Date Submitted: [15 September, 2004] Source: [J. Foerster] Company [Intel] Address [JF3-212, 2111 NE 25th Ave., Hillsboro, OR, 97124] Voice:[503-264-6859], FAX: [503-264-3483], E-Mail:[jeffrey.r.foerster@intel.com] Re: [Informational] Abstract: [This presentation gives an update of the current ITU-R TG1/8 recommendations for UWB compatibility with various wireless services.] Purpose: [For discussion by IEEE 802.15 TG3a.] Notice: This document has been prepared to assist the IEEE P802.15. 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 P802.15. J. Foerser, Intel

2. State of International UWB Regulations in ITU Jeff Foerster Intel CorporationSeptember 16, 2004 J. Foerser, Intel

3. Purpose of this presentation • Provide the IEEE 802.15.3a body with some insight into the current state of the current ITU TG1/8 recommendations • Bring awareness to UWB community about challenging state of current recommendations • Build upon nice summary of regulatory result presented in doc. IEEE 802.15-04/340r0 (authors T. Ikegami, T. Yasui, R. Kohno) • Discuss possible areas the UWB industry could contribute to improve current recommendations • Contribute technical analysis addressing some of the coexistence scenarios in the current recommendations • Possible assumptions to revisit: UWB device activity factors, usage scenarios, path loss models • Describe benefits of UWB technology to companies and individual country regulators participating in TG1/8 • Attend TG1/8 meetings and/or individual country delegation meetings showing industry support for enabling worldwide spectrum harmonization for UWB • Solicit feedback from task group to determine how best the IEEE can help support international harmonization of regulations which could have significant impact on 802.15.3a and .4a J. Foerser, Intel

4. General Problem Statement • UWB as a generic underlay technology has the potential of causing harmful interference • First, must admit there could be a problem in some coexistence scenarios • Simple example  UWB device 1 meter from a generic narrowband receiver • Given above criteria and usage model (1 meter separation), allowed Tx power could be significantly lower than FCC Part 15 limits J. Foerser, Intel

5. General Problem Statement • On positive side  only a few wireless services would be anticipated to meet this particular usage scenario (i.e., cell phones, indoor WiMax systems, RLANs, Bluetooth) • Note that indoor WiMax systems can operate at 3.4-3.6 GHz where this usage scenario may be relevant • Implications of simple example • UWB emissions limits must be evaluated on a per service basis and not treated as a simple underlay technology, but rather a secondary or tertiary user of the shared spectrum • Note that current ITU recommendations based upon protection criteria of current services, typically taking the form of an I/N ratio, contributed by individual ITU-R WP • I/N < -6 dB common, I/N < -20 dB used for some fixed services • Challenges to generalizing interference analysis • Interference analysis dictated by underlying assumptions about interference criteria, usage models, device activity models, channel models, and other system parameters • Some of these parameters require projecting future use, which is inherently difficult and subjective • Simple example certainly has its limitations and does not address: • Single UWB devices near systems with high gain antennas • Aggregation of interference from multiple UWB emitters (office and home environments) J. Foerser, Intel

6. Some Tentative ITU Recommendations *Based upon 1 foot separation (1 meter separation limits would be ~10 dB higher) • Based upon dithered, average power results (not peak) at 10 meters. • I/N < -20 dB (criteria). • Conclusions stated local restrictions could ensure sufficient protection distances (600 m) to allow -41 dBm/MHz Tx power. J. Foerser, Intel

7. Some Tentative ITU Recommendations *Based upon 30m separation distance from single outdoor UWB device. *Based upon 1 dB degradation to SNR (criteria still in discussion). Other service not shown here: Mobile Services (Land, Maritime, Aeronautical, Amateur, Amateur Satellite), Mobile Satellite (MSS, RNSS), Broadcasting Services, other Science Services (EESS, Meteorological Radar) * Additional information can be found in doc. IEEE 802.15-04/340r0 (authors T. Ikegami, T. Yasui, R. Kohno). J. Foerser, Intel

8. Comparison of FCC mask to current ITU Recommendations • Clearly, current ITU recommendations would make UWB unusable for high-rate communications systems (not all services accounted for below) Propose ETSI ‘sloped mask’ RLAN Fixed Services Cellular J. Foerser, Intel RAS

9. Comments on current ITU Recommendations • Current recommendations makes UWB unusable for high-rate communications • However, there are a number of technical areas worth revisiting • Most interference criteria based up meeting an I/N limit (interference-to-thermal noise ratio, -6 dB and -20 dB typical, depending on service) • This criteria can be very conservative…in some cases, criteria results in limits well below OOB and unintentional radiation limits for other devices • Activity factors need to reflect realistic expected UWB device operation • Intel and others have submitted modifications to these factors in the ITU and encourage others to support the new data and/or contribute their own data • Usage models need to reflect realistic expected UWB device operation • Time sharing of spectrum in high density environment should be considered (many devices associated with same piconet and time-sharing coordinated by MAC) • Outdoor use expected to be rare (mainly peer-to-peer synchronizing of data)…countries can limit outdoor infrastructure (as is done in US) • In many cases, path loss models based upon free space propagation, which may be unrealistic • Accurate path loss modeling is critical, and should not be chosen lightly • Lots of discussion on path loss models in Annex 2: Methodologies for interference analyses of systems using UWB technology with systems operating under Radiocommunication Services show NLOS path loss with exponent >2 • Some analysis use free space path loss even when indoor-to-outdoor propagation is encountered J. Foerser, Intel

10. Comments on current ITU Recommendations • Other areas worth contributing to in ITU recommendations • Mitigation techniques could be used by both UWB devices and some of the narrowband services • Power control could be implemented by a UWB device to lower potential interference • Countries could limit outdoor use of UWB devices initially • Some services, like RAS and EESS, could increase protection area via localized regulations/laws • Static or dynamic notching techniques could be applied by a UWB device • Why do the current recommendations differ so much from FCC mask? • Current ITU protection criteria is very different from that used by FCC (FCC has stated that comparing interference to thermal noise is not sufficient criteria) • This is a difficult parameter and can be subjective, depending on service • Different services exist in different frequency bands which were not considered by FCC during proceedings • WiMax systems are allocated 3.4-3.6 GHz in much of the world, recent NPRM could allow WiMax systems at 3.6 GHz in the US…this service did not exist during FCC proceedings • Some countries are considering allocation of spectrum in the 3-4 GHz band for future cellular (B3G) systems • Some services in US operating in ‘unlicensed’ spectrum, while same services are given primary use of the same spectrum (RLANs in the 5 GHz bands) • FCC lets market decide in the US how best to deal with potential interference in these bands • Primary and secondary user designation outside of US dictates that sharing must be regulated more explicitly • Based upon current analysis and ITU process, it looks unlikely that FCC mask (or even ETSI mask) will be recommended by the ITU-R TG1/8 • Based upon above discussion, there are good reasons to have a different mask J. Foerser, Intel

11. Fixed Service Analysis Revisited • Recall: Fixed services occupy most of the spectrum in 3.1-8.5 GHz • Obviously, this analysis has implications on most of the ‘in-band’ spectrum currently allocated in the US • A number of scenarios studied • (1) Single indoor UWB device impact on indoor FS terminal at 1 meter separation distance • (2) Single outdoor UWB device impact on outdoor FWA and P-P system • (3) Multiple UWB devices in a multi-story office building near a FWA and P-P system • (4) Multiple UWB devices in a residential area near a FWA and P-P system J. Foerser, Intel

12. Fixed Service Analysis Revisited • Comments on Case (1) Single indoor UWB device impact on indoor FS terminal at 1 meter separation distance • Current recommended PSD: -70 dBm/MHz • Suggest PSD used for frequencies up to ~ 5 GHz • However, main spectrum targeted for indoor FWA equipment (WiMax) would occupy only 3.4-3.6 GHz • Based upon current criteria of I/N < -6 dB, analysis supporting recommendation looks sound • Potential mitigation techniques using adaptive detection and avoidance strategies could enable use of the spectrum on an opportunistic basis and prevent the need for a permanent notch • Comments on Case (2) Single outdoor UWB device impact on outdoor FWA and P-P system • Current recommendation (extrapolation from graphs…not explicit in doc.) • FWA at 3.5 GHz: ~ -53 dBm/MHz • PP at 4 GHz: ~ -60 dBm/MHz (~ -53 dBm/MHz at 7.7 GHz, ~ -50 dBm/MHz at 10.5 GHz) • Based upon current criteria of I/N < -20 dB • Does not take into account limited outdoor UWB device activity J. Foerser, Intel

13. Fixed Service Analysis Revisited • Comments on case (3) • Intel has contributed to text in Annex 3 showing the aggregating interference is significantly lower when considering realistic WPAN association models • Currently, results have not been incorporated in recommendations P-P aggregated interference from WPAN typical deployment in comparison with the “generic hot-spot” potential worst case. ~20-25 dB difference Trial of the revised “Hot Spot” scenario used for the calculation of the aggregate power in this UWB application *Simulations provided by Fabrice Labourasse, Mikhail Lyakh, Oleg Semenov. J. Foerser, Intel

14. Fixed Service Analysis Revisited • Comments on case (4) Multiple UWB devices in a residential area near a FWA and P-P system • Assumptions • Interference criteria: I/N < -20 dB • Path loss model: Free space • 33% assumed LOS (included outdoor devices + indoor through window propagation) • 100% and 21% peak activity factors (for each device) • Discussion includes potentially adding a 5 dB safeguard margin • I/N < -20 dB is already very conservative • 5 dB safeguard margin does not seem necessary on top of conservative I/N < -20 dB J. Foerser, Intel

15. Fixed Service Analysis Revisited • Comments on case (4): Impact of channel model and activity factor • Note: Using free space propagation, interference  ∞ as size area  ∞ (clearly not realistic) Evaluation of interference to 4GHz P-P FS receiver with different propagation models for 10000 indoor devs/km2, 5% activity factor ~35 dB difference Interference model for high density urban environment Rx int. level meeting I/N=-20dB *Analysis and simulations not yet submitted to TG1/8… planned contribution for November meeting. *Simulations provided by Fabrice Labourasse, Mikhail Lyakh, Oleg Semenov. J. Foerser, Intel

16. Take-aways • Current ITU-R TG1/8 recommendations would make UWB unusable for high-rate communications • There are a number of technical areas which merit revisiting in the analysis • Activity factors • Usage models • Path loss models • Balancing the aggregation of a number of conservative assumptions • Balancing OOB emissions requirements for other services compared to in-band recommendations for UWB • There may be other areas worth revisiting which are specific to a particular service (expected minimum separation distance, antenna responses, etc.) • Some services may require emissions below FCC mask • Indoor WiMax systems in 3.4-3.6 GHz ! • RAS ? • RLAN in 5 GHz bands ? • Many other services in ITU-R TG1/8 recommendation show a need for emissions below FCC mask…results after revisiting analysis based upon revisiting above areas are TBD J. Foerser, Intel

17. Working Documents and Timelines • Current open working documents in the ITU-R TG1/8 • Compatibility Report • Compatibility Recommendation • Characteristics Recommendation • Methodology Recommendation • Regulatory Framework Recommendation • ITU-R TG1/8 meetings ITU-R Recommendations Individual Country Proceedings / Authorizations Current date to finalize Recommendations (2 Interim Meetings) 9/29- 10/5 5/18- 5/27 11/4 – 11/10 2004 2005 2006 2007 2008 J. Foerser, Intel

18. Implications and Call to Action • Many countries are looking to the ITU-R TG1/8 to providing recommendations for specific country regulations • It currently looks unlikely the FCC mask will be recommended, and for valid reasons • ITU-R TG1/8 recommendations will have significant impact on the IEEE 802.15.3a standard, if we want this standard to meet international requirements • We need to change the perception of UWB technology as a generic overlay technology • UWB technology should be considered as a secondary or tertiary user of the available spectrum which is capable of re-using spectrum in a very localized area using a low transmit power spectral density (PSD) • The low PSD enables the sharing and reuse of spectrum with services not expected to be in close proximity as long as the aggregation of multiple devices in realistic deployments does not cause harm • UWB technology is not just ‘below the noise floor’ of every device • Some services which are expected to operate in very close proximity can cause harmful interference • Aggregation of interference needs careful study, using realistic assumptions, to ensure all services are protected • The UWB industry needs to work with users of the shared spectrum to come up with a mutually agreed upon sharing plan • We will not succeed in creating a harmonized, useful set of regulations without engaging with and working with users of the spectrum we would like to share J. Foerser, Intel

19. Implications and Call to Action • Companies wishing to see UWB viable outside the US must engage with both local regulatory bodies and ITU-R task groups and working parties • Both regulators and other companies (especially one’s who may not have direct interest in UWB) must understand why UWB is necessary to support some applications • The only way to achieve very high peak throughputs (future Gbps) at low cost and low power consumption at short range is to have available spectrum which is >= desired peak throughput • Other technologies can achieve high throughputs, but not at the cost and complexity potentially achievable by UWB based systems • Greater UWB industry support is needed to show the high level of interest and desire for this technology • What can the IEEE do to help improve the current state of the ITU-R TG1/8 recommendations? • What can your company do to help improve the current state of the ITU-R TG1/8 recommendations? J. Foerser, Intel