Features
• 24 dB Gain
• 5 dB Noise Figure
• Probe-Power Bias Connection
• Compact Size
Benchtop/General Purpose Use
Used alone on the bench, the Agilent 87405B
Preamplifier can be added to any application in which
additional gain and low noise are required. The compact and inexpensive 11899A probe power supply is a
suitable source of DC bias in remote applications.
The Agilent 87405B preamplifier brings reliable gain
and low noise figure to measurement systems to
improve overall system performance and reduce systematic errors. With its compact size and convenient
probe-power bias connection, the 87405B is ideal for
use as the front end preamplifier for a variety of
Agilent instruments such as the 8590E Series of
portable spectrum analyzers. The 87405B is the recommended preamplifier for use with the 8594E Noise
Figure Measurement Solution. The rugged design
along with its insertable configuration of connectors
makes the 87405B ideal for test port applications.
Agilent 87405B
Preamplifier 10 MHz to 4 GHz
Data Sheet
2
Improve Noise Figure Measurements
Add a preamplifier to noise figure measurement systems
to significantly lower system noise figure. The noise figure of the system is dominated by the noise figure of the
preamplifier
.
F
new
= F pa + F
sys
- 1
G
pa
Where F and G are noise figure and preamplifier gain,
both in linear terms
.
NF
sys
= 10 log (F
sys
) in dB
For systems having a single preamplifier, where the gain
of the preamplifier is greater than or equal to the spectrum analyzer noise figure, the system noise figure
approximately equals the noise figure of the pre-
amplifier.
Increase Sensitivity and Speed
Adding preamplifiers to measurement systems can
improve sensitivity for measuring low-level signals. Boost
the sensitivity of your Agilent spectrum analyzer 15 to
25 dB by using the 87405B Preamplifier. Alternatively,
better sensitivity can be traded for measurement speed.
Spurious tests often require narrow resolution bandwidths to reduce the noise floor of the analyzer, allowing
low-level signal detection. An analyzer with low noise
figure allows you to use a wider resolution bandwidth,
yet achieve the same sensitivity. Sweeptimes can
improve one hundred times for each decade increase in
bandwidth. The 87405B Preamplifier has gain and noise
figure characteristics that optimize dynamic range and
sensitivity.
Gain(dB)
28
0.01
1.0
2.0
3.0 4.0 5.0
6.0
Frequency(GHz)
Specification Typical
Output Power(dBm) @ 1 dB compression(dB)
12
11
10
9
8
7
6
5
4
3
2
0.01 0.5
Noise Figure(dB)
6
5
4
3
2
Specification Typical
Specification Typical
1.5
2
2.5
Frequency(GHz)
3.5 4 4.5
3
5
1
5.5
6
1
0
0.01
1.5
1
2.5
2
Frequency(GHz)
3.5
3
4.5
4
5.5
5
6
Loading...