Hi Leyo -

See coments in

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I am trying to measure the ACP of a multi-carrier basestation transmitter using PXA signal anlyzer.

The carriers are spaced @ 1MHz and there are 6 carriers with GMSk modulation. Power of each carrier is 36.4 dBm.

**I hope you have ample external attenuation applied since the safe input level to the PXA is +30 dBm, and you are inserting +36 dBm!!**
In the ACP setup for carrier configurations, there is a a button called "Measurement Noise BW". What is the siginificance of this BW. Is this the BW in which the acrrier power is measured?.

**After you press: Configure Carriers button, press the green Help key, then press Measurement Noise Bandwidth key. You will now see the description of the key. Indeed this is the BW which the carrier power is measured.**
My carriers BW is 200 KHz(GMSK) . But seeting the measurement noise BW to 200 KHz, the measured power of each carriers is around 1.5 dB less than the expected 36.4 dBm. To get carrier power of 36.4 dBm, the measurement BW should be around 1MHz?

**Yes, the 36.4 dBm carrier power is the total carrier power of all 6 carriers. Each individual carrier power is less, and the 6 carriers “add” to provide the expected 36.4 dBm total carrier power.**
Also is this tied to the measurment method of "Integ BW" and "RRC weighted". Please explain the difference between these methods.

**The Help feature used above does not answer this question. While on the subject of where to find more information, please see the PXA User’s and Programmers Reference at:**
**http://cp.literature.agilent.com/litweb/pdf/N9060-90027.pdf**
**See: http://en.wikipedia.org/wiki/Root-raised-cosine_filter**
Regards -