1. doc.: IEEE 802.15-10-0489-00-wng0 Submission September, 2010 Shoichi Kitazawa, ATRSlide 1 Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [A Proposal Toward Better Use of Spectrum Resources in future WPAN ] Date Submitted: [9 July, 2010] Source: [Shoichi Kitazawa, Kazuto Yano, Satoshi Tsukamoto, Tomohiro Miyasaka, Makoto Taromaru* and Masazumi Ueba] Company [ATR, * Currently with Fukuoka University] Address [2-2-2, Hikaridai Seika, Kyoto, 619-0288, JAPAN] Voice:[+81 774951511], FAX: [+81 774951508], E-Mail:[kitazawa@atr.jp] Abstract:[In this presentation, We measured how spectrum is utilized in a situation where several radio systems are operated autonomously with high traffic loads. And we introduce concept of an access mechanism for future WPAN.] Purpose:[Introduces the concept of an access mechanism for future WPAN.] 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.

2. doc.: IEEE 802.15-10-0489-00-wng0 Submission September, 2010 Shoichi Kitazawa, ATRSlide 2 A Proposal Toward Better Use of Spectrum Resources in Future WPAN Shoichi Kitazawa Kazuto Yano Satoshi Tsukamoto Tomohiro Miyasaka Makoto Taromaru* Masazumi Ueba (ATR, * Currently with Fukuoka University) {kitazawa, kzyano, tsukamoto, miyasaka, ueba}@atr.jp

3. doc.: IEEE 802.15-10-0489-00-wng0 Submission September, 2010 Shoichi Kitazawa, ATRSlide 3 Introduction/Background ISM band is getting more and more crowded. Expanding use of this band by various systems such as Bluetooth, ZigBee, and other systems as well as WLAN. Recent movement of "smart" system will boost this tendency. High traffic-load situation may be caused frequently in future, which degrades the efficiency of the overall communications due to inter-system interference among co-existing wireless systems. In addition, wireless devices will be more widely used in future even in system/machine control applications that request very high reliability.

4. doc.: IEEE 802.15-10-0489-00-wng0 Submission September, 2010 Shoichi Kitazawa, ATRSlide 4 We present here Demonstration to visualize how current different systems in the 2.4GHz band behave in a congested (high traffic-load) situation. Co-existence of WLAN and Bluetooth (BT) as a typical example Trying to utilize spectrum resources as much as possible A proposal to start discussions of advanced technologies to enhance the efficiency of 2.4GHz communication and reliability. The use of DSA, the dynamic spectrum sensing technology

5. doc.: IEEE 802.15-10-0489-00-wng0 Submission September, 2010 Shoichi Kitazawa, ATRSlide 5 Demonstration of high-traffic situation with WLAN and BT We measured how spectrum is utilized in a situation where several radio systems are operated autonomously with high traffic loads. –Four pairs of WLAN(11b) operated with ch. 1, 5, 9, and 13 –One pair of Bluetooth –Execute long file transfer with FTP.

6. doc.: IEEE 802.15-10-0489-00-wng0 Submission September, 2010 Shoichi Kitazawa, ATRSlide 6 Setup Configuration Measurement system is setup in anechoic chamber (22.5m x 14.5m x 12m). Scenario –Case1: All WLAN Link are same TX power –Case2: On of WLAN link is low TX power Photo of measurement system Allocation of equipment

7. doc.: IEEE 802.15-10-0489-00-wng0 Submission September, 2010 Shoichi Kitazawa, ATRSlide 7 Measurement results (Case1) Optimum situation is assumed. Each AP transmits same power. WLAN and BT shearing spectrum resources Still remain unused spectrum ch1ch5ch9ch13 ch1ch5ch9ch13 each dot indicating BT After 1 min.

8. doc.: IEEE 802.15-10-0489-00-wng0 Submission September, 2010 Shoichi Kitazawa, ATRSlide 8 Measurement results (Case2) Rather realistic situation is assumed. –Transmission power of AP at ch. 13 reduced 10dB. Bluetooth takes position of WLANs channel and thus makes rather wide whitespace. – It makes many residual and useless radio resources and degrades spectral efficiency ch1ch5ch9ch13 ch1ch5ch9ch13 WLAN stopped After 2 min.

9. doc.: IEEE 802.15-10-0489-00-wng0 Submission September, 2010 Shoichi Kitazawa, ATRSlide 9 Short summary As is demonstrated, each system tries to utilizes its assigned spectrum resources in 2.4GHz band, however it resultantly makes resources unused and uselessly left more than expected under high traffic-load situations. In order to enhance the efficiency of spectrum use and reliability of communication, we feel the necessity of new technology for future WPAN.

10. doc.: IEEE 802.15-10-0489-00-wng0 Submission September, 2010 Shoichi Kitazawa, ATRSlide 10 DSA, the dynamic spectrum access DSA has been introduced into IEEE 802.22 and IEEE 802.11 TGaf. We has been also studying DSA and detailed MAC protocols suitable for WPAN, based on our concerns as shown in the demonstration.

11. doc.: IEEE 802.15-10-0489-00-wng0 Submission September, 2010 Shoichi Kitazawa, ATRSlide 11 Schematic diagram of DSA Realize Spectrally Efficient Use & Sharing of Radio Resources using Dynamic Spectrum Access/Assignment. DSA will be promising access mechanism for future WPAN.

12. doc.: IEEE 802.15-10-0489-00-wng0 Submission September, 2010 Shoichi Kitazawa, ATRSlide 12 In near future we may face with high traffic-load situation in 2.4GHz band. In preparation to this, we wish to propose here to kick the discussions of better use of spectrum resources shared by different systems in their own manners. As a promising technology we presented here the use of DSA for WPAN. Acknowledgment This work is supported by the Ministry of Internal Affairs and Communications under a grant Research and development on radio resource control technologies among multiple radio systems on same frequency band. Proposal and Conclusions