Since we already know pmin for 15db snr at the output

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Unformatted text preview: PI ,Total 3 Pmin where Pmin is the minimum input signal power for a specified output SNR. Since we already know Pmin for 15dB SNR at the output, we just need to plug it in the above formula. Then DR 2 3 5.5 ( 105.5) 66.67 ( dB ) [12-7 Solution] The dynamic range of the receiver before the addition of the attenuator is: (i) DRbef ore = [ (i) PI PI 2 23 = [3 . M DS k (Ts + Te )Bn S N Ro,min (i) When the attenuator is added the input intercept changes to PI L and the effective input temperature of the system increases from Te to To (L − 1) + Te L so the new dynamic range is: (i) DRw/atten = [ 2 PI L3 . k (Ts + To (L 1) + Te L)Bn S N Ro,min In order for the new dynamic range to be larger than the old dynamic range, the following inequality must hold: L 1 > Ts + To (L − 1) + Te L Ts + Te Rearrange the inequality to find: Ts > To . Thus, if the source (antenna) temperature is greater than To , then adding the attenuator will increase the system dynamic range. 1 [12-9 Solution] Since gain compression ca...
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This homework help was uploaded on 03/13/2014 for the course ECE 453 taught by Professor Staff during the Spring '08 term at University of Illinois, Urbana Champaign.

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