Channel and Coding Implementation » History » Version 11
Version 10 (PASCHOS, Alexandros, 12/15/2015 02:49 AM) → Version 11/17 (Gimenez Silva, Adriana, 12/15/2015 09:22 AM)
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h1. *Channel and Coding Implementation*
h2. *AWGN Channel*
After establishing a basic channel, AWGN was then added as shown on Figure 5.5. The AWGN function has an Eb/No input, which is the target Eb/No of the signal (the Eb/No received).
p=. !{width: 60%}https://sourceforge.isae.fr/attachments/download/1503/withAWGN.png(AWGN Implementation)!
_Figure 5.5 Communication Diagram_
h2. *Coding*
In order to further improve the communication chain, coding is applied to this channel, a illustrated in figure 6. The BER function in LabVIEW compares the received bit stream to the Galois generated PN sequence. Figure 5.6. At this point, as mentioned in the limitations, synchronization between the two USRP was an issue. From issue since the time the Vi was ran, there was a delay of 3 seconds on the receiving side, plotting noise, before correcting plotting the constellation. The received bits did not maintain keep a fixed value (since the transmitter and receiver were continuously transmitting and receiving) value, but rather kept changing (between 0 and 1) throughout the test, giving a BER of 1. For this reason, it was necessary to calculate the BER without the use of USRPs.
p=. !{width: 60%}https://sourceforge.isae.fr/attachments/download/1505/withCoding.png(Channel and Coding)!
_Figure 5.6 AWGN and Coding_
h1. *Channel and Coding Implementation*
h2. *AWGN Channel*
After establishing a basic channel, AWGN was then added as shown on Figure 5.5. The AWGN function has an Eb/No input, which is the target Eb/No of the signal (the Eb/No received).
p=. !{width: 60%}https://sourceforge.isae.fr/attachments/download/1503/withAWGN.png(AWGN Implementation)!
_Figure 5.5 Communication Diagram_
h2. *Coding*
In order to further improve the communication chain, coding is applied to this channel, a illustrated in figure 6. The BER function in LabVIEW compares the received bit stream to the Galois generated PN sequence. Figure 5.6. At this point, as mentioned in the limitations, synchronization between the two USRP was an issue. From issue since the time the Vi was ran, there was a delay of 3 seconds on the receiving side, plotting noise, before correcting plotting the constellation. The received bits did not maintain keep a fixed value (since the transmitter and receiver were continuously transmitting and receiving) value, but rather kept changing (between 0 and 1) throughout the test, giving a BER of 1. For this reason, it was necessary to calculate the BER without the use of USRPs.
p=. !{width: 60%}https://sourceforge.isae.fr/attachments/download/1505/withCoding.png(Channel and Coding)!
_Figure 5.6 AWGN and Coding_