1. doc.: IEEE 802.11-09/1210r1 Submission Nov 2009 Tuncer Baykas, NICT.Slide 1 Energy Detection vs Common Mode Signaling Detection for Coexistence Authors:

2. doc.: IEEE 802.11-09/1210r1 Submission Nov 2009 Tuncer Baykas, NICT.Slide 2 Abstract This presentation compares energy detection with Common Mode Signaling detection in 802.15.3c and 802.11ad systems and shows necessity of “Signal detection” such as “Common Mode Signaling” for co- existence of 60 GHz systems.

3. doc.: IEEE 802.11-09/1210r1 Submission Nov 2009 Tuncer Baykas, NICT.Slide 3 802.15.3c Coexistence 802.15.3c has following rules to promote coexistence among devices using different PHYs as specified in the IEEE Std 802.15.3.c-2009: All PNCs shall send a CMS beacon/sync frame in every superframe All PNCs shall be able to receive the CMS beacon/sync frame. All SC DEVs shall be able to send and receive signal in CMS –Any new PNC seeking to start a piconet, shall initially perform channel scan. Upon receiving CMS beacon/sync frame from an already-active PNC, this new PNC will be aware of its existence and shall avoid interfering signal transmission” What if PNCs rely on Energy detection before creating their piconets. Detection only

4. doc.: IEEE 802.11-09/1210r1 Submission Nov 2009 Tuncer Baykas, NICT.Slide 4 Simulation Setup and Results are from parameters used in 09/0559r0 Matlab (ray tracing) Room configuration –Dimension (LxWxH) 6m x 12m x 3m –5 specular reflectors/piconet random location 2dB reflection loss PNC –Number of antennas = 1 patch antenna element (random orientation) –Transmission power = 10 dBm –Noise Figure=8 dB –Implementation loss=2 dB 6m PNC1PNC2 d m 12m 1m 3m Radiation pattern of a single patch antenna (peak gain ~ 3dBi) reflector Patch antenna

5. doc.: IEEE 802.11-09/1210r1 Submission Nov 2009 Tuncer Baykas, NICT.Slide 5 CMS Detection versus Energy Detection CMS Detection Probability 95% for 5m CMS preamble detection requires -83 dBm received signal power. In 802.11 systems, energy detection requires 20 dB more received energy level than that of carrier sense, therefore -63dBm is required. Energy Detection Proabability 5% for 5m Results: 5m distance case Energy detection probability is only 5% While CMS detection probability is 95%

6. doc.: IEEE 802.11-09/1210r1 Submission Nov 2009 Tuncer Baykas, NICT.Slide 6 Office Cubicle Environment Cubicle configuration –Dimension (LxWxH): 2.5m x 1.8m x 3m –5 specular reflectors/piconet (random location, 2dB reflection loss) –Partition wall: 3dB penetration loss 1.8m PNC1PNC2 d m 2.5 m.5m.9m Office partition Penetration loss ~3dB CMS Detection rate 95% for 4m Energy Detection Rate 5% for 4m Results: 4m distance case Energy detection probability is only 5% While CMS detection probability is 95%

7. doc.: IEEE 802.11-09/1210r1 Submission Nov 2009 Tuncer Baykas, NICT.Slide 7 If systems from different PHYs will try to rely on only energy detection, the probability of detection is very limited such as 1/20 of “signal detection”. This means CMS detection is necessary especially for video streaming. What is needed to detect a CMS beacon/sync frame preamble? 1)Same channelization with 802.15.3c-2009 2)A matched filter to detect preamble sequences. Easy to accomplish, it will protect 802.11 system from 802.15.3c interference, if APs have this capability. Advantages of CMS detection

8. doc.: IEEE 802.11-09/1210r1 Submission Nov 2009 Tuncer Baykas, NICT.Slide 8 If 802.11ad systems send CMS frames perodically, they will prevent 802.15.3c systems from starting piconets on the same channel. What is needed to send a CMS syncframe? 1)Same channelization as defined in IEEE Std 802.15.3c- 2009 2)Creating a predetermined sequence with Pi/2 BPSK modulation at 1760 Msymbols/s as defined in IEEE Std 802.15.3c-2009 Advantages of CMS transmission for 802.11ad

9. doc.: IEEE 802.11-09/1210r1 Submission Nov 2009 Tuncer Baykas, NICT.Slide 9 Conclusions Compared with energy detection, detecting CMS signals gives 802.11ad systems more protection against interference from 802.15.3c piconets. This is especially important for uncompressed video streaming applications, which are vulnerable to interference. By sending a CMS beacon, 802.11ad systems can create a protective zone. As long as 802.11ad systems utilize the same channelization and same symbol timing with 802.15.3c, additional complexity of sending and detecting CMS is minimal.

10. doc.: IEEE 802.11-09/1210r1 Submission Evaluation Methodology Update Add section to evaluation methodology to measure proposals ability to detect preambles of: –IEEE Std 802.15.3c-2009 (primary) –ECMA-387 –WirelessHD Add section to evaluation methodology to measure ability of other 60 GHz systems to detect proposed preamble: –IEEE Std 802.15.3c-2009 (primary) –ECMA-387 –WirelessHD Nov 2009 Tuncer Baykas, NICT.Slide 10