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RF Amplifier not amplifying signal

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LandLack

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Hi, I don't understand something about the amplifiers I'm using during my simulations with ADS; my circuit has a square signal which has been previously upconverted to 410MHz. I need to amplify this signal from -20 dbm to near 0dbm, so I use an amplifier. After the simulation, with "Harmonic Balance" (power amplitude-frequency) I see that the signal has really been amplified by about 18 dB (to -2.1dBm), but when I see the "Transient" result it is displayed that the amplitude of the voltage hasn't changed (it seems to have been decreased from 31mV to 27mV). Shouldn't power be (V^2)/R? Why can't I see a voltage amplification of (about) 10 if the power has been amplified by (about) 100 times?

Since the harmonic balance seems to confirm the datasheet values, I don't think that something in my schematic was wrong. I'm giving you the graphs obtained in an attached image.amplimm.png AmplImm.png
 

jiripolivka

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An upconverted "square" signal will create a spectrum with two side bands. One should be rejected by a filter. Your "simulation" makes no sense at 410 MHz.
 

LandLack

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An upconverted "square" signal will create a spectrum with two side bands. One should be rejected by a filter. Your "simulation" makes no sense at 410 MHz.[/QUOTE


This is a "Harmonic Balance" simulation, and does not show the entire frequency spectrum, but only an impulse with the power amplitude value on the carrier frequency; Agilent ADS doesn't give you the possibility to see the signal the usual way we are used to, probably because it requires too much computation. Here is the image of the schematic with the simulation tools: **broken link removed** .
The bias tee is needed to remove the DC signal from the output (and some other purposes), and doesn't interfere with frequencies higher than 50MHz (I have tried working without, but still had the same results. The 50ohm load replaces the next component.
While the frequency view may be misunderstood since it's unorthodox view, I can assure you that it's very dependable when you hame many tones; the transient view is the same as usual.
Here is a hint about Harmonic Balance: https://en.wikipedia.org/wiki/Harmonic_balance ;
 
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LandLack

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**broken link removed**
Sorry I had some difficulties in uploading the image
 

wdwxn

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Like transistor, it,s the current that been amplified . not voltage.
 

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