doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 1 DTV signal stochastic behavior at the edge of the protected contour and resulting probability of detection from various sensing schemes. IEEE P Wireless RANs Date: Authors: Notice: This document has been prepared to assist IEEE 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 Patent Policy and Procedures: The contributor is familiar with the IEEE 802 Patent Policy and Procedures 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 Chairhttp://standards.ieee.org/guides/bylaws/sb-bylaws.pdf Carl R. StevensonCarl 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 Working Group. If you have questions, contact the IEEE Patent Committee Administrator at >

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 2 TV signal availability at edge of contour Required DTV field strength: 41 dBuV/m at 615 MHz ( 20 log F scaling needed to compensate for the antenna effective aperture, 4π/λ 2 ) Probability for DTV: F(50,90) –Location: 50% with standard deviation of 5.5 dB –Time: 90% with standard deviation depending on distance from the transmit station Required DTV field strength: 64 dBuV/m Probability for Analog TV: F(50,50) –Location: 50% with standard deviation of 8.3 dB (VHF) and 9.5 dB (UHF) –Time: 50% with same standard deviation as DTV

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 3 ITU-R P.1546 propagation model Three main propagation variations: –Medium scale: Local ground cover variations due to obstructions in the vicinity of the receiver. Scale is in the order of these obstructions. Propagation results were measured over 500 m to 1 km squares –standard deviation was established with confidence over these squares –probability over adjacent squares should be statistically independent Flat land was assumed Propagation results were averaged over few λ’s to remove the impact of multipath –Small scale: Multipath variations in the order of the wavelength typically following the Rayleigh model –Large scale: Path variations due to changes in geometry of the entire propagation path such as presence of hills, etc. Need to include topographic data (TIREM, CRC-Predict, etc.) Localization of the sensors relative to the terrain will be needed: geolocation

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 4 ITU-R P.1546 propagation model (cont’d) For planning purpose: –Location variability will include a degree of multipath fading (rooftop antenna falling in a multipath null that cannot be optimally positioned) –It will also include some variability over greater distances. Probability for DTV: F(50,90) –Location: 50% with standard deviation of 5.5 dB –Time: 90% with standard deviation depending on distance from the transmit station (variations caused by tropospheric propagation effects (e.g., ducting), leaves in deciduous trees, etc.) (σ time can be found for the given location from the predicted field strength from the difference between F(50,50) and F(50,90)) Probability for NTSC: F(50,50) –Location: 50% with standard deviation of 8.3 dB (VHF) and 9.5 dB (UHF) –Time: 50% with same standard deviation as DTV

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 5 Example at the edge of coverage of a 1 MW, 300 m height DTV station Propagation model = ITU-R P.1546 –Distance of protected contour from the DTV transmitter = 118 km –σ location = 5.5 dB –F(50,90) = 41 dB(μV/m) F(50,50) = 46.7 dB(μV/m) –σ time = (F(50,50)-F(50,90))/Q -1 (90%)= (56-41)/1.28= 4.46 dB Composite propagation –Sum of two log-normal distributions = log-normal (μ 1 +μ 2, σ 1 2 +σ 2 2 ) –DTV signal variability at protected contour = log-normal ( μ = 46.7 dB(μV/m), σ = 7.08 dB)

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 6 Example at the edge of coverage of a 1 MW, 300 m height DTV station Propagation model = FCC Curves –Distance of protected contour from the DTV transmitter = 96.8 km –σ location = 5.5 dB –F(50,90) = 41 dB(μV/m) F(50,50) = 51.4 dB(μV/m) –σ time = (F(50,50)-F(50,90))/Q -1 (90%)= ( )/1.28= 8.12 dB Composite propagation –Sum of two log-normal distributions = log-normal (μ 1 +μ 2, σ 1 2 +σ 2 2 ) –DTV signal variability at protected contour = log-normal ( μ = 51.4 dB(μV/m), σ = 9.8 dB)

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 7 Channel bandwidth variability If channel bandwidth is smaller, there will be more flat fading occurrences due to very small excess delay (1/BW) multipath Sensing will be more difficult due to the additional signal fades Frequency fading within the useful bandwidth is treated elsewhere (captured DTV signals) ITU-R DSB Handbook, "Terrestrial and satellite digital sound broadcasting to vehicular, portable and fixed receivers in the VHF/UHF bands", Geneva, 2002 Channel bandwidth Rural signal standard deviation 6 MHz5.5 dB 200 kHz5.67 dB 80 kHz5.9 dB 10 kHz6.99 dB

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 8 Conversion from field strength to SNR at input of sensing detector

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 9 Sensing technique performance (Thomson DTV segment detector) Sampling= 4.06 ms Pfa= 10 %

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 10 Sensing technique performance (Thomson DTV segment detector) Sampling= 4.06 ms Pfa= 10 % μ= 8.9 dB σ= 7.08 dB

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 11 Sensing technique performance (Thomson DTV segment detector) Sampling= 4.06 ms Pfa= 10 %

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 12 Sensing technique performance (Thomson DTV segment detector) Sampling= 4.06 ms Pfa= 10 % P detection = %

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 13 Sensing technique performance (I2R covariance absolute value detector) Sampling= 4 ms Pfa= 1 %

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 14 Sensing technique performance (I2R covariance absolute value detector) Sampling= 4 ms Pfa= 1 %

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 15 Sensing technique performance (I2R covariance absolute value detector) Sampling= 4 ms Pfa= 1 %

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 16 Sensing technique performance (I2R covariance absolute value detector) Sampling= 4 ms Pfa= 1 % P detection = %

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 17 Sensing techniques performance comparison Note: Pd= % at -116 dBm Pd=98.535% Pd=95.953%

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 18 Sensing techniques performance comparison Pd=98.535% Pd=95.953% Pd=99.482% Pd=99.843%

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 19 Sensing techniques performance comparison

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 20 Sensing techniques performance comparison

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 21 Sensing techniques performance comparison

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 22 Sensing techniques performance comparison

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 23 Collaborative sensing P LFA : Probability of a local false alarm at a CPE P LMD : Probability of a local misdetection at a CPE P GFA : Probability of a global false alarm at the BS P GMD : Probability of global misdetection at the BS L: number of statistically independent CPEs Any local false alarm causes a global false alarm Any local detection causes a global detection (OR)

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 24 Sensing technique performance (I2R covariance absolute value detector) Sampling= 4 ms Pfa= 1 % P detection = %

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 25 Impact of multiple sensors on log-normal curve

doc.: IEEE /0112r0 Submission March 2007 Gerald Chouinard, CRCSlide 26 Collaborative sensing Special consideration With simple OR gating of sensor reports, the Pfa will tend to increased rapidly with the number of sensors Pfa for individual sensors can be controlled by asking for repeated sensing times before reporting (each sensing window is independent statistically since it works against thermal noise) Data fusion at the base station should be based on “majority vote” (e.g., 2 out of 6 sensors) from a small number of well selected statistically independent CPEs (e.g., 6 sensors in the same topographic area located at more than 500 m) to provide a high level of probability of detection while keeping Pfa low.