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PNA-X pulsed measurement using receiver leveling

Question asked by nsm on Nov 22, 2012

I am using a PNA-X GHz unit for testing pulsed amplifiers. The frequency band is 3.1 to 3.5 GHz.The pulse width is 100us and the PRF is 1ms. The input drive level to the amplifier is 10dBm. The amplifier is connected to the PNA-X through some switch matrices as we are doing automated measurments.Taking into account the losses of the switch matrices,the power level that I need to set is around 14dBm. Since the PNA-X cannot deliver this power at the frequency band, I am using a booster amplifier, 83018A connected between the src aout and cplr in on the PNA-X. I have the following.questions. 

1. Currently ,i am using the open loop method to level the power. But as per app note 1408-21, using the open loop method, there might be a power jump at the band crossing of 3.2GHz and it is recommended to use the receiver leveling. I do see a power jump at 3.2GHz and it appears randomly and calibrating the analyzer seems to solve the problem. But again this is very random.
2. To solve the above problem, it is recommended that, the analyzer be calibrated in cw mode and then turn on receiver leveling and then apply the pulse settings. For the pulsed mode, do we need to turn off the ALC? 
3. I need to synchronise the measurement to an external pulse, I am trigerring the pulse generators inside the PNA-X using the external pulse sync in. For the pulse width that i am using for measurement, which is the best mode for pulsed measurment? Is it the wideband or the narrow band mode?
4. How do I arrive the delay settings for the pulse generators?
5. Since, I am using a booster amplifier do I need to calibrate the system in the pulsed mode? if so, then how do I apply receiver leveling?