Unmodulated carrier and modulated carrier for the center frequency point

[zcmm]

Hi, for carrier and modulation carrier signal is confusing.

1. What is the difference between their center frequency point for same frequency? Or modulated carrier will change center frequency? if it is,why?

2. What is the difference between tx power?? Or modulated carrier will change tx power? if it is,why?

PCA1004 Dk SMA connect with the attenuator( attenuation value is -14dbm),then i use constant carrier and PRBS9,the tx power is as follow: why tx power is weak? constant carrier picture:

PRBS9 picture:

i use SMS connector,the result as follow:

[zcmm]

it is HP8594E

[Jørn]

What output power have you configured the chip for?

[zcmm]

i never do not configured the output power,the default value is 0dbm

[Jørn]

Are the your cables and connectors specified for 50 Ohm? You should be getting around 0dBm, possibly a little bit lower but not much. It might be a good idea for you to ensure the spectrum analyzer is operating as it should by measuring a source with known output power. That way you can either exclude your measurement setup as a source of error, or find any fault that may lie with it.