aaron_do
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Hi everybody,
I have a question about LNA power consumption. Suppose we have a system with say 16 channels, and the maximum input of the system is -20 dBm. At this signal level, the LNA's power consumption is much larger than at small signal. For example instead of 5 mA (-60 dBm) it could be 15 mA (-20 dBm = 31 mV pk into 50 ohm). This is because the bias point of the input transistor has changed.
Most papers I read quote the low end power consumption (5 mA). However, the standard might specify a blocker level much higher than the signal level...for example -30 dBm 802.11.
1) First question: if blocker level = -30 dBm, does that mean every other channel can have -30 dBm, so for 16 channels, total blocker ~ -30 + 12 dB = -18 dBm (approximately since actually there are only 15 blocking channels)
2) Secondly if this is true, won't this drain the power supply since the system must amplify all channels before channel selection.
thanks, Aaron
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