ORFS Reference Power Different? - RF Cafe Forums

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lucious
 Post subject: ORFS Reference Power Different?
Posted: Fri Aug 08, 2008 5:10 am 
 
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Joined: Tue Apr 22, 2008 8:24 am
Posts: 1
Hi Guys,

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.

According to 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,
10log [ (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.

Please let me know if you need further details.

Thanks in advance!


BR
Lucious




Posted  11/12/2012