Hi
who knows any guid or application note describe step by step how to design microwave power amplifier ,i have cripps books but it is not as clear as it should be
Hi
who knows any guid or application note describe step by step how to design microwave power amplifier ,i have cripps books but it is not as clear as it should be
Hi
who knows any guid or application note describe step by step how to design microwave power amplifier ,i have cripps books but it is not as clear as it should be
hi eladg!
i want to design a microwave pulse PA that outputs 110W operating on 2.3GHz ,and i want to use PH2226(macom's transistor)..can u give me some application notes.
Hi
who knows any guid or application note describe step by step how to design microwave power amplifier ,i have cripps books but it is not as clear as it should be
hi eladg!
i want to design a microwave pulse PA that outputs 110W operating on 2.3GHz ,and i want to use PH2226(macom's transistor)..can u give me some application notes.
hi
can we use s parameters to design power amplifier matching
the sparameters which i have are measured at large signal not at small signal as it is at 8v 250 mA but many books say that we can not use s parameters to do the matching
any comments are welcome
When you use s-parameters for matching, you are assuming the transistor is running in the small signal linear conditions. With power amplifiers, the operating point of the device shifts over the RF cycle which makes the s-parameters not very useful. What you should do is a load pull analysis. Plots these contours for gain/IP3/Pout on a Smith chart. Then you can select the match for the desired gain/IP3/Pout.
When you use s-parameters for matching, you are assuming the transistor is running in the small signal linear conditions. With power amplifiers, the operating point of the device shifts over the RF cycle which makes the s-parameters not very useful. What you should do is a load pull analysis. Plots these contours for gain/IP3/Pout on a Smith chart. Then you can select the match for the desired gain/IP3/Pout.
hi toonafishy:
can u give me somes details abt the analysis、simulation and measurement of load-pull ?
by the way , give me some info. about high power transistors vender
thax alt!!!!
When you use s-parameters for matching, you are assuming the transistor is running in the small signal linear conditions. With power amplifiers, the operating point of the device shifts over the RF cycle which makes the s-parameters not very useful. What you should do is a load pull analysis. Plots these contours for gain/IP3/Pout on a Smith chart. Then you can select the match for the desired gain/IP3/Pout.
hi toonafishy:
can u give me somes details abt the analysis、simulation and measurement of load-pull ?
by the way , give me some info. about high power transistors vender
thax alt!!!!
to make load pull u need tuner, and it is not easy to do.
u can use s parameter, get the linear model (for one bais point) and then change the output res to 80-75% of his value and then u can use the new s-parameter to match it.
about the gain u know the p1dB from the datasheet
You can use small signal S-parameter provided to match for gain and check its stability under small signal operation. To design power amplifier, you definitely need tuner to find out the optimum load impedance either by passive load pull or active load pull. You need 2 tuners if you implement Passive load pull. Source Pull for power gain and load for high output power. For accurate device characterization, you should try active load pull. Bear in mind, active load pull need complete load pull system, which is very expensive.
Besides load pull experiement to achieve high output power and PAE, you should also consider the layout, heatsink and DC biasing circuit. Consider using thermally and electrically conductive epoxy if you design High frequency Power Amplfier (10W at X/KU band). It helps a lot as I faced this problem before.