K
ρ
(τ)
ρ(t)
x(t) = ±a
t
k
t
k
θ
p(θ) = η exp(−ηθ), θ ≥ 0,
η
ψ(τ) = a
2
exp(−2η|τ|).
x(t) = ±a
t
n
= nT
0
+ η, n = 1, 2, 3, . . . T
0
= const η
[0, T
0
] p
q
ψ(τ) = a
2
n −
|τ|
T
0
(p − q)
n−1
+ a
2
|τ|
T
0
−(n − 1)
(p − q)
n
,
(n −1)T
0
≤ |τ| < T
0
.
p = q = 1/2
3
R
2
0
2
[1 + K
ρ
(τ)] K
A
(τ)
A(t) = R
0
[1 + ρ(t)]