the fet gate needs a slightly negative bias voltage on the gate to operate correctly. So they use a bias network to inject DC voltage onto the gate, without adding any RF insertion loss to the RF path. The 10 NH and 100 ohm resistor act as an "open circuit" to the RF signal, and the 1000 pf shunt cap keeps any stray RF from leaking back to the power supply.
The circuit is wrong as drawn, there needs to be a series DC blocking capacitor at the RF input port. Without it, the amp will probably not work. at 2 GHz, a 100 pF series cap should be sufficient.
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the fet gate needs a slightly negative bias voltage on the gate to operate correctly. So they use a bias network to inject DC voltage onto the gate, without adding any RF insertion loss to the RF path. The 10 NH and 100 ohm resistor act as an "open circuit" to the RF signal, and the 1000 pf shunt cap keeps any stray RF from leaking back to the power supply.
The circuit is wrong as-drawn, there needs to be a series DC blocking capacitor at the RF input port (labeled "2.5-3 ghz"). Without it, the amp will probably not work. at 2 GHz, a 100 pF series cap should be sufficient.