Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)

1. Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [On the UWB coexistence and collocation with mobile devices] Date Submitted: [14 May, 2003] Source: [Pekka Ranta] Company [Nokia] Address [Itämerenkatu 11-13, Helsinki, Fin-00180,Finland] Voice:[+358504836467], FAX: [+358718036467], E-Mail:[pekka.a.ranta@nokia.com] Re: [If this is a proposed revision, cite the original document.] Abstract: [Current FCC spectrum mask does not guarantee UWB devices to be colocated in mobile devices. In addition external UWB devices may cause serious loss in cellular capacity if not separated by several meters. The presentation enlightens these problems showing a few example calculations. The material presented here is also contributed to ITU WP8F Doc 8F/864-E by Nokia] Purpose: [That the coexistence and colocation issues with mobile devices are also paid attention in the UWB air interface selection process.] 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. Pekka Ranta, Nokia

2. Outline • Drivers for UWB and mobile coexistence • Implications of FCC spectrum mask • Reduced cellular capacity • Safety distance • Conclusion Pekka Ranta, Nokia

3. External UWB radio • FCC mask requires safety distance of several meters for mobile devices UWB RADIO Pekka Ranta, Nokia

4. Internal UWB radio Close proximity networking • Integration of • mobile phones, camcorders, cameras, remote displays • high capacity memories for downloads e.g. movies, newspapers, etc drives high data rates in mobile devices Movies UWB Newspapers Pekka Ranta, Nokia

5. -40 -45 -50 Allowed emission [dBm/MHz] -55 -60 -65 -70 -75 3 4 -80 10 10 Frequency [MHz] UWB Emission Limits UWB tolerable and allowed (FCC) emissions WLAN IMT-2000 PCS -41.3 dBm/MHz - 40 - 45 -51.3 dBm/MHz Outdoor - 50 Indoor - 55 Allowed emission [dBm/MHz] - 60 - 65 - 70 - 75 1 GHz 10 GHz Pekka Ranta, Nokia

6. Power budget comparison • WCDMA sensitivity -with thermal noise - 100.2 dBm -with 1 dB addon interference - 99.2 dBm • UWB interference -at WCDMA band -45.5 dBm -Interference margin -10 dB =>0.4dB loss WCDMA sensi • Required isolation -63.7 dBm Pekka Ranta, Nokia

7. Loss in cellular capacity • by UWB interference Pekka Ranta, Nokia

8. Safety distance 1/2 Isotropic antennas assumed with G=0dB UWB interference power 6dB below WCDMA sensitivity => 1dB add in WCDMA sensitivity Pekka Ranta, Nokia

9. Safety distance 2/2 Pekka Ranta, Nokia

10. How to achieve better isolation? • Distance separation 1m => 40 dB • Antenna orthogonality 10 dB • Sharper spectral shaping X dB • Lower transmit power X dB Colocation with mobiles requires sharp spectral shaping of UWB TX signal Pekka Ranta, Nokia

11. Conclusions • UWB PHY should be designed clearly better spectral properties than FCC mask allows to enable • harmonius coexistence mobile devices • colocation of UWB radio in mobile devices Pekka Ranta, Nokia