Signature based sensing algorithms January 2007 Signature based sensing algorithms IEEE P802.22 Wireless RANs Date: 2007-01-11 Authors: Notice: This document has been prepared to assist IEEE 802.22. 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 grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s sole discretion to permit others to reproduce in whole or in part the resulting IEEE Standards publication. The contributor also acknowledges and accepts that this contribution may be made public by IEEE 802.22. Patent Policy and Procedures: The contributor is familiar with the IEEE 802 Patent Policy and Procedures http://standards.ieee.org/guides/bylaws/sb-bylaws.pdf including the statement "IEEE standards may include the known use of patent(s), including patent applications, provided the IEEE receives assurance from the patent holder or applicant with respect to patents essential for compliance with both mandatory and optional portions of the standard." Early disclosure to the Working Group of patent information that might be relevant to the standard is essential to reduce the possibility for delays in the development process and increase the likelihood that the draft publication will be approved for publication. Please notify the Chair Carl R. Stevenson as early as possible, in written or electronic form, if patented technology (or technology under patent application) might be incorporated into a draft standard being developed within the IEEE 802.22 Working Group. If you have questions, contact the IEEE Patent Committee Administrator at patcom@iee.org. > Wen Gao, ThomsonWen Gao, Thomson Inc.

Abstract Field-Sync based DTV signal detection and simulation results January 2007 Abstract Field-Sync based DTV signal detection and simulation results Segment-Sync based DTV signal detection and simulation results Simulations utilize the ATSC A/74 DTV signal captures [1] with following parameters DTV channels were sampled at 21.524476 Msample/sec and down converted to a low central IF frequency of 5.38 MHz Wen Gao, ThomsonWen Gao, Thomson Inc.

Signature in ATSC DTV signals January 2007 Signature in ATSC DTV signals Field Sync and Segment sync are two important time domain signatures of ATSC DTV signals Wen Gao, ThomsonWen Gao, Thomson Inc.

Simulation Procedure for Field Sync Detector January 2007 Simulation Procedure for Field Sync Detector Lowpass filter bandwidth: 6MHz AWGN is filtered using the same lowpass filter Correlation detector use a matched filter that matches the field sync pattern: [1 -1 -1 1] + PN511+PN63+zeros(1,63)+PN63 Decision statistics: the maximum magnitude value of the field sync correlator output within a field (24.2ms) Wen Gao, ThomsonWen Gao, Thomson Inc.

January 2007 Simulation results of the field sync detector (Average over 50 data capture ensembles) Wen Gao, ThomsonWen Gao, Thomson Inc.

Simulation Procedure for Segment Sync Detector January 2007 Simulation Procedure for Segment Sync Detector Lowpass filter bandwidth: 6MHz AWGN is filtered using the same lowpass filter Wen Gao, ThomsonWen Gao, Thomson Inc.

Segment Sync Detector structure January 2007 Segment Sync Detector structure Test Statistics is Where L=1664, ND is number of collected sgements, K=8, M=1 or K=4, M=2 Wen Gao, ThomsonWen Gao, Thomson Inc.

Simulation results of the Segment sync detector January 2007 Simulation results of the Segment sync detector The curves are obtained by average results over 12 data captures [2]. PFA = 10 percent, observation time = 31 ms ( ND = 400) -110 -109 -108 -107 -106 -105 -104 -103 -102 10 -2 -1 Received Signal Power (dBm) P MD 4 every other sample autocorrelation 8 consecutive sample autocorrelation Wen Gao, ThomsonWen Gao, Thomson Inc.

Sliced segment sync detector January 2007 Sliced segment sync detector when the observation time is long, timing drift effect will restrict the improvement of the performance comes from longer observation time. In order to alleviate the timing drift effect, we can slice total observation time into multiple slices , and then apply segment sync detector to each slices The total observation time can be discontinuous while each slice contains continuous observation time. Finally we use the average (or summation) of the test statistics of each slice as our overall test statistics. We will call this detector as Sliced Segment Sync Detector (SSSD) Wen Gao, ThomsonWen Gao, Thomson Inc.

Simulation results of Sliced Segment-sync detector (1) January 2007 Simulation results of Sliced Segment-sync detector (1) Use data capture ensemble: WAS_3_27_06022000_REF PFA = 10 percent One slice for 2.156ms, 3.123ms, 4.06ms; two slices for 9.25ms -110 -108 -106 -104 -102 -100 -98 10 -2 -1 Received Signal Power (dBm) P MD 2.156 ms 3.123 ms 4.06 ms 9.25 ms Wen Gao, ThomsonWen Gao, Thomson Inc.

Simulation results of Sliced Segment sync detector (2) January 2007 Simulation results of Sliced Segment sync detector (2) The curves are obtained by average results over 12 data captures [2] PFA = 10 percent Observe 4.06ms or 9.25ms per 10ms frame. Two slices for 9.25ms -115 -114 -113 -112 -111 -110 -109 -108 -107 10 -2 -1 Received Signal Power (dBm) P MD 4.06 ms x 10 frames 9.25 ms x 10 frames Wen Gao, ThomsonWen Gao, Thomson Inc.

January 2007 Conclusions Segment sync detector has low computation complexity with good performance. Segment sync detector can be used for discontinuous observation interval, just like power detector. Both the results of Segment sync detector and field sync detector provide high confidence about the presence of ATSC DTV signals. Field sync and segment sync detector are complementary to energy or eigenvalue-based detector. A combination of both types of detector will provide a good solution for 802.22. Wen Gao, ThomsonWen Gao, Thomson Inc.

January 2007 References Victor Tawil, “DTV Signal Capture Database”, IEEE 802.22-06/0081r0, May, 2006. Steve Shellhammer, Victor Tawil, Gerald Chouinard, Max Muterspaugh, and Monisha Ghosh, “Spectrum Sensing Simulation Model”, IEEE 802.22-06/0028r10, September, 2006. Wen Gao, ThomsonWen Gao, Thomson Inc.