Agilent Technologies N4373A User Manual page 113

Specifications and Regulatory Information
N O TE
N O TE
N O TE
112
• dBo: specifically the ratio of optical powers ('o' for
'optical').
• dBe: specifically the ratio of electrical powers ('e' for
'electrical').
• dBm: an electrical or optical power level related to 1 mW.
Differences of powers in dBm are written as "dBo" for optical powers or
"dBe" for electrical powers.
• dB : the square of the
A/W
efficiency") R related to A/W,
calculated as
which equals
Differences of responsivities in dB
Because such a difference is measured as differences of
electrical (RF) powers on the Network Analyzer, it may be
also written as "dBe" (with the same numerical value).
• dB is defined correspondingly to dB
W/A
For O/E and E/O converters with linear relation between optical power
and electrical current, values in dBo correspond to half the values in dBe.
This is because the optical power is proportional to the electrical current I
and the electrical power is proportional to the square of I.
Electrical noise floor (of LCA electrical in) The average electrical
power displayed by the NWA when no signal is applied to
LCA electrical in, expressed in dBm. No signal means:
• for O/E: the LCA electrical in port is terminated with 50
Ohm load.
• for E/O: the LCA electrical out is terminated with 50 Ohm
load, LCA optical in is darkened.
• for O/O: the LCA optical in is darkened.
Agilent N4373A Lightwave Component Analyzer, First Edition
Responsivity (or "conversion
2
R
-------------- -
10log
⁄
10
A W
R
-------------- -
20log
⁄
10
A W
are written as "dB".
A/W
A/W
Introduction
.