Confused bu balanced amplifier output power when one amplifier is bad

hello all,

I simulated balanced amplifier and found the total output power decreased 6dB when one amplifier is bad, but, some aiticles say that it's 3dB not 6dB will decreased.


I use two 3dB hybrid couplers, two same amplifiers and one outputs 30dBm,the total output power of the 2nd hybrid coupler is 33dBm. It's right. BUT, when i set one amplifier's gain to -100dB and the total output power is 27dBm which means 6dB decreased.

Thanks.

That's right. I don't know what's your problem.
3dB degraded in power is compared to single PA output,
6db degraded in power is compared to dual PA output.

Yeah,I got the result that"3dB degraded in power is compared to single PA output,
6db degraded in power is compared to dual PA output.
"