Detection Thresholds of Iterative MIMO Processing


 
  

  




    
  




  

   
  

        
  
   



   
   

   
     
  

      

  
 

 

     
 

 

    
 
  

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M transmit antennas x1

constellation mapper

binary source

code rate R

interleaver

Π

y2

x2

outer encoder

s H

n AWGN

plain convolutional code or parallel concatenated (turbo) code (PCC)

... y LD1 inner MIMO detector

LE1

Π

-1

LA2

outer soft in/out decoder

hard decision

binary sink

LD2,i LD2

N receive antennas

^ x2

interleaver

inner information bits

LA1 &  '

R

deinterleaver

Π

outer coded bits

LE2

 

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       1 Eb/N0 = 3dB

Gray mapping 4x4, QPSK 0.8

mutual information at output of detector IE1

mutual information at output of detector IE1

1

5dB Eb/N0 = 4dB 3dB

0.6

2dB

1dB

0.4

0.2

0

Gray mapping QPSK (unless otherwise stated)

0.8

4x8

0.6

4x4

4x2

2x1

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M 2x2, 64QA

4x1

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mutual information at input of detector IA1 &  (

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