Electro-Metrics EM-2115, Инструкция по эксплуатации

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ELECTRO-METRICS EM-2115 2.0 OPERATING INSTRUCTIONS
(EM2115S2-10)
measuring strong narrowband signals. It is not recommended for weak narrowband signal meas-
urements.
The assumptions listed in a thru c can also be applied when comparing amplitude meas-
urements made in the medium and widest bandwidths. The only exception is that the possibility
of the wideband measurement being influenced by nearby signals, other broadband signals, or
higher noise levels.
2.4.5 Signal Measurements
The 9 kHz to 1 GHz frequency range contains many signals and noises that have different
characteristics. One way to distinguish amongst these various signals is by the width of the spec-
trum they occupy. Broadband signals with their extensive spectrum cause different effects in a
receptor compared to narrowband signals; thus they often need to be classified separately. MIL-
STD-461 has traditionally required separate measurements of broadband and narrowband signals
and noise, with different limits being applied to each.
NOTE: The procedure for determining if a signal response is
broadband or narrowband in character is given in 2.4.7.
When the frequency spectrum of a detected signal is wider than the bandwidth of the re-
ceiver, the response is classified as being broadband. Broadband measurements are made with
the detector mode set for Peak and the widest bandwidth setting for the frequency range being
used or the bandwidth required by the applicable test standard.
The broadband correction factor, which is bandwidth dependent, is added to the measured
peak signal level to obtain the broadband level in terms of dB(µV/MHz) (dB relative to one mi-
crovolt per MHz).
NOTE: Typical factors are noted in Table 2.1 while actual factors
are given in Appendix D.