Rohde & Schwarz URV5-Z4 - Page 50

3.8
Test
Setup
for
leasurenent
of
Reflection
Coefficient
The
URVS
and
the
VSWR
Bridge
ZRBZ,
Mod;
52,
can
be
combined
to
form
an
accurate
and
low-priced
test
setup
for
measurement
of
re-
flection
coefficients
in
the
frequency
range
10
MHz
to
2
GHz
(Fig.
3-6).
Due
to
the
high
directivity
of
the
VSWR
bridge
(>
46
dB),
the
measurement
error
for
low
reflection
coefficients
is
only
t(0.5%
+
10%
of
rdg).
The
test
setup
is
therefore
suitable
for
checking
the
reflection
coefficient
of
URVS
probes
from
ap-
proximately 500 MHz and above. The output power' of the sweep
generator
may
be
between
O
and
+26
dBm.
In the test setup according to Fig. 3-6 the URVS measures the
ratio
of
reflected
and
incident
power
and
reads
out
the
result
as
reflection
coefficient
or
return
loss.
The
reflected
power
is
de-
termined
by
means
of
the
power
sensor
in
the
main
measurement
channel
(B
in
Fig.
3-6),
the
incident
power
by
means
of
the
1oo-v
insertion
unit
in
the
second
channel.
Since
even
with
total
re-
flection
only
part
of
the
input
power
will
be
transmitted
to
the
bridge
output,
the
transmission
loss
must
also
be
considered
in
the
measurement.
The
transmission
loss
is
13
dB
and
almost
inde-
pendent
of
frequency.
The
transmission
loss
is
entered
as
attenu-
ation
correction
value
+13
dB
for
the
main
measurement
channel
(section
2.3.5.3).
In
both
channels
the
selected
unit
is
v.
In
the
relative
readout
mode
X/REF
the
reflection
coefficient
is
directly
indicated
(1%
I
0.01),
in
the
A63
mode
the
return
loss
(in
dB).
It
is
not
recommended
to
determine
the
transmission
loss
by
means
of
a
short
circuit
or
open
circuit,
since
with
reflec-
tion
coefficients
>
30%
the
VSWR
at
the
bridge
input
and,
hence,
the
measurement
error
strongly
increases.
URVS
settings
tabularized:
Channel B 'Channel A
Autorange
on
on
Unit
V
V
Measurement
speed
F2
I
F2
Attenuation
correction
+13
dB
------
Relative readout AEXT
X/REF (AdB)
.394.ao1o.02
3.30
3-2
3.8
Test Setup for .easutenent of Reflection
Coeffieient
The URVS ad to
form an
T-'Q"
flection coefficients in frequency 10 to 2 GHz
(Fig. 3-6). Due to
bridge
(>
46
dB) ,
the measurement error for low reflectíon coefficients is
only ±(0.5% + 10% of rdg) . The t,est Setup is therefore suitable
for checking the reflection coefficient of URV5 probes fror ap-
proximately 500 MI-lz and above. The Output power of the sweep
generator may be between 0 and
+26
dBm.
The vswa Bridge ZRB2, Mod. 52, Can be
combined
accurate and low~priced test Setup for measurement of
the
_ range MHz
the high directivity of the VSWR
In The test Setup according to Fig. 3-6 the URV5 measures the
ratio of reflected and incident power and reads out the result as
reflection coefficient er return loss. The reflected power is de-
termined by ne ans of the power Sensor in the main measurement
Channel (B in Fig. 3-6),
Insertion Unit in the Second Channel. Since even Voith total re-
flection only part of the Input power will be transmitted to the
also be considered in
13 dB and almosen inde-
is entered as attenu-
main measurement Channel
Selected Unit is v. In
reflection coefficient is
AdB mode the return loss
to determine the transmission loss
› since Voith reflec-
30% the VSWR at the bridge Input and, hence,
bridge Output, the
transmission loss must
the
measurement. The transmission loss is
pendent of frequency. The
transmission loss
ation correction Value +13 dB for the
(section 2.3.5.3). In both Channels the
the relative readout mode X/REF the
directly indicated (t% = 0.01), in the
(in dB). It is not recommended
by ne ans of a Short circuit er open circuit,
tion coefficients >
the measurement error strongly increases.
the incident power by ne ans of the 100-V
URV5 settings tabularized:
Autor arge
Unit
Measurement Speed
Attenuation correction
Relative readout
Channel B
on
v
F2
+13
dB
AEXT
X/REF
(AdB)
ııllllllllllli
'Channel A
on
v
F2
-ı-----
394.8010.02
3.30
E-2