Recently, during testing, I request
the DUT to transmit the signal at EGSM, CH38 and
PL5. and I measure it using both R&S CMU200
and Agilent 8960. The Reference Power for "Spectrum
due to Switching" is around 33.87dBm, whereas the
Reference Power for "Spectrum due to Modulation"
is around 25.73dBm. So, I was wondering why there
is about 8.14dB different.
my colleague, he mention that this is because of
the definition of the "Spectrum due to Modulation"
which require the average power of the whole channel,
which is average power of the 8 time slots. And
after calculating using the 33.87dBm,
[ (10^33.87/10) / 8 ] = 24.84dBm
the value calculated
is 24.84dBm, but it has around 1dB different from
the measured power.
So I am curious whether
is the method that my colleague thought me is wrong
or is the way of the instruments measure differently.
Please do let me know about why is this happened.
And I’m interested on how these Reference Power
are calculated/measured as well.
let me know if you need further details.
Thanks in advance!