Handbook of Propagation Effects for Vehicular and ... - Courses

Table of Contents
10 Optical Methods for Assessing Fade Margins ____________________________ 10-1
10.1 Background ______________________________________________________ 10-1
10.2 General Methodology ______________________________________________ 10-2
10.3 Skyline Statistics of Austin and San Antonio, Texas _____________________ 10-3
10.4 Clear, Shadowed and Blocked Propagation States ______________________ 10-5
10.5 Urban Three-State Fade Model (UTSFM) _____________________________ 10-8
10.6 Estimation of Urban Fading for the Globalstar Constellation _____________ 10-9
10.6.1 Cumulative Fade Distributions for Urban Areas In Tokyo, London, and Singapore___ 10-10
10.7 Statistics of Potentially Visible Satellites in Various States_______________ 10-11
10.8 Satellite Diversity ________________________________________________ 10-13
10.8.1 Single and Joint Fade Distributions________________________________________ 10-13
10.8.2 Diversity Gain Versus Probability for Tokyo, London, and Singapore_____________ 10-16
10.9 Summary Comments and Recommendations__________________________ 10-17
10.10 References ______________________________________________________ 10-18
Table of Figures
Figure 10-1: Example of fisheye lens image in Austin, Texas.............................................................. 10-2
Figure 10-2: Skyline derived from image shown in Figure 10-1........................................................... 10-3
Figure 10-3: Skyline elevation angle histogram for San Antonio, Texas............................................... 10-4
Figure 10-4: The left set of curves denotes measured and modeled fade distributions in Japan (urban
regions) at 32° elevation and f = 1.5 GHz. The right-hand curves represent the fade
differences between the measured and modeled distributions at different percentages. ................. 10-7
Figure 10-5: Cumulative fade distributions at 1.5 GHz for a family of elevation angles for urban
Japan. Curves were derived using the UTSFM described in text. Indicated elevation angles
are centered within ± 2° intervals............................................................................................... 10-9
Figure 10-6: Cumulative fade distribution for Globalstar satellite constellation associated with
“highest” satellite diversity scenario. The path state vector components for London, Tokyo,
and Singapore are given in Table 10-5. ..................................................................................... 10-11
Figure 10-7: The joint probability for state mixtures of two, three, and four potentially visible
satellites assuming the Globalstar constellation for observations made in Tokyo........................ 10-12
Figure 10-8: The joint probability of state mixtures of two, three, and four potentially visible
satellites assuming the Globalstar constellation for observations made in London...................... 10-12
Figure 10-9: The joint probability of state mixtures for two, three, and four potentially visible
satellites assuming the Globalstar constellation for observations made in Singapore. ................. 10-13
10-i