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Power conversion from CW to GSM, GPS modulated ??

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Wilson_yu_chen

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Hi Professional,

I remember that Phase noise which often refer to CW carrier for GSM TXVCO
can be used to calculate GSM modulated power for certain offset to (desired channel) frequency. It means that if I want to get TXVCO PN requirement by the clue of modulation spectrum of GSM @ 400KHz offset, which is -60dBc, then,
PN (dBc/Hz) = -60-10log(30KHz)-factor(GSM power spreading)
= -60-44.7-8=-112.7dBc/Hz.
Factor=1 if CW, no modulation.
PS: ORFS modulation spectrum @ 400KHz is 30KHz RBW based measurement.

So How is that factor applied to GPS, Bluetooth, DVB-H... different type of modulation application ? Any table I can refer from website or ..??

Thanks !!!
Happy New Year.
 

RiffMaster

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You said that Spreading Factor for GSM is 8.
May I know from where is coming that number?
 

Wilson_yu_chen

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Mmmm..

I think this's a approximation number or ratio of integration power
of CW and GMSK modulation.
But I have not done this yet

Regards,
 

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