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

Summary of Recommendations 12-19
12.10.1 Urban Three-State Fade Model
The photogrammetric method employs the Urban Three-State Model (UTSFM), where
the probability density function f ν (PDF) for the signal envelope has the following form
fν ( ν, α ) = C( α ) f Rice( ν) + S( α ) f Loo( ν) + B( α) fLoo(
ν)
, (12-28)
where C( α ), S( α ), B(
α ) are probabilities of clear, shadowed, and blocked states and are
dependent on the elevation angle α . The Ricean density distribution is given by
2 [ − K(
v + 1)
] I ( 2Kv)
f Rice(
v)
= 2Kvexp
o . (12-29)
Loo’s density function is given by
f Loo
( 20log(
v)
− m)
( v)
= 8.
686
2
π
∞
Kv 1 ⎡
exp⎢−
σ ∫ v 0 ⎣
2
2σ
2
2 2 ⎤
− K(
v + z ) ⎥
⎦ , (12-30)
× I ( 2Kvz)dz
0
where v is the received voltage relative to the clear path voltage, K is the ratio of the
direct power received to the multipath power, Io ( v)
is the modified Bessel function with
argument v , m is the mean of log v , and σ is the standard deviation of log v . The
parameters K , m,
σ are tabulated in Table 12-6 for urban Japan at 1.5 GHz and
C( α ), S( α ), B(
α ) are listed in Table 12-7 as a function of elevation angle (averaged over
a 360° azimuth).
Table 12-6: Fade parameters of the Urban Three-State Fade Model.
Fade State PDF Type Parameter Urban 3-State
C Rice K 5.9
S Loo
B Loo
K
m
σ
K
m
σ
20
10
2
501
100
5.4