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chris2312 New Member Offline Posts: 6	sensitivity of lna Nov 04^th, 2011, 5:02am Hello, I want to calculate or simulate the power of the minimum detectable signal of a LNA, but I have no idea how to get it. I have data of simulated noise figures of the lna, but I think that I only can calculate it with assumption of a special SNR of the signal or could I calculate/simulate it otherwise ? Thanks for response.
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loose-electron Senior Fellow Offline Best Design Tool = Capable Designers Posts: 1638 San Diego California	Re: sensitivity of lna Reply #1 - Nov 5^th, 2011, 12:53pm minimum detectable? At what channel BW, SNR, or what BER? A little more info on what you are looking for please.
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chris2312 New Member Offline Posts: 6	Re: sensitivity of lna Reply #2 - Nov 8^th, 2011, 6:43am Yes the minimum detectable signal, which could be handled with the LNA. I have a dualband-LNA at 5.8 GHz and 2.4 GHz and it reaches a NF of 3.4 dB and 3 dB. What do you need ? The channel BW ist 150 MHz and 100 MHz repectively. About the SNR that was also a question. Do I have to assume a special SNR to calculate it ? Thanks.
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raja.cedt Senior Fellow Offline Posts: 1516 Germany	Re: sensitivity of lna Reply #3 - Nov 8^th, 2011, 8:02am hello, SNR depends on the BER you are intersted at the o/p and BER specified by the standard Thanks, raj.
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loose-electron Senior Fellow Offline Best Design Tool = Capable Designers Posts: 1638 San Diego California	Re: sensitivity of lna Reply #4 - Nov 8^th, 2011, 11:01am Minimum detectable sounds more like a marketing term - need the defined SNR - BER to define this.
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wave Senior Member Offline Posts: 117 Silicon Valley	Re: sensitivity of lna Reply #5 - Nov 8^th, 2011, 1:27pm MDS is common in some types of systems. �Closely related to SNR. http://en.wikipedia.org/wiki/Minimum_detectable_signal
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aaron_do

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Re: sensitivity of lna
Reply #6 - Nov 13^th, 2011, 5:23pm

Hi,

by minimum detectable signal, you probably mean the sensitivity. But that depends on the rest of your system. As far as I know, NF is usually enough for an LNA only. Of course if you want to specify sensitivity as limited by interference, you also need IIPn.

If you really want to know the sensitivity due to the LNA alone, its just the noise floor plus the NF plus the required SNR to meet BER specifications.

regards,
Aaron

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loose-electron Senior Fellow Offline Best Design Tool = Capable Designers Posts: 1638 San Diego California	Re: sensitivity of lna Reply #7 - Nov 14^th, 2011, 10:00am Yes the SNR and BER question - but no response to whats needed...
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