
76-1
76.1 Introduction
Radio location is concerned with the use of radio waves for position sensing and locating objects. For
this purpose, the radio signals can be used in an active or passive mode. In the passive mode, the charac-
teristics
of th
e
ra
dio
sig
nals
re
ceived
by a pa
rticular
ob
ject
sit
uated
in th
e
e
ld
ar
e
us
ed
to de
termine
th
e
lo
cation
. I
n
t
he
a
ctive
c
ase,
t
he
si
gnals
g
enerated
b
y
a
n
o
bject
y
ield
t
he
i
nformation
a
bout
i
ts
l
ocation
.
e
re
a
re
n
umerous
r
adio
l
ocation
m
ethods
e
mployed,
b
eing
•
Ba
ckscattered
p
roperties
w
aves,
f
or
e
xample,
r
adio-frequency
i
dentication
(
RFID),
o
r
r
adar
•
Re
ceived
si
gnal
s
trength
(
RSSI)
•
Ti
me
o
f
a
rriva ...