Changeset 9602

Timestamp:

10/01/09 00:43:26 (4 years ago)

Author:

hvolos

Message:

added text, updated figures

Location:

ossiedev/branches/hvolos/docs/OSSIETalkWithUSRP

Files:

• OSSIETalkWithUSRP.tex (modified) (7 diffs)
• blockdiagram2.png (modified) (previous)

ossiedev/branches/hvolos/docs/OSSIETalkWithUSRP/OSSIETalkWithUSRP.tex

@@ -75 +75 @@
 \section{Version}
 This lab is for use with OSSIE version 0.7.x and the OSSIE Eclipse Feature (OEF), running on a
-computer or VMware image that uses Fedora Core 7 or Ubuntu 8.04. The following components are required: OSSIETalk, PacketResizer, Conv\_Enc, DigitalModulator, FrameAssembler, amplifier, Interpolator, USRP\_Commander, amplifier, Decimator, AutomaticGainControl, FrameSynchronizer, DigitalDemodulator, and Conv\_Dec.
+computer or VMware image that uses Fedora Core 7 or Ubuntu 8.04. The following components are required: OSSIETalk, PacketResizer, Conv\_Enc, DigitalModulator, FrameAssembler, amplifier, Interpolator, USRP\_Commander, Channel, Decimator, AutomaticGainControl, FrameSynchronizer, DigitalDemodulator, and Conv\_Dec.
 
 \section{Procedure}
@@ -163 +163 @@
 \paragraph{Channel1}
 \begin{verbatim}
+AWGN Noise Power=400000
+Fading type=None
 \end{verbatim}
 
@@ -171 +173 @@
 \end{verbatim}
 \subsubsection{Waveform Testing}
-Run the waveform and press the ``Push to Talk'' button while talking at the microphone. You should hear your voice from the speakers. Note that the CVSD encoding used has an inherent distorsion. At 400000 noise power (20dB SNR) the any channel distorsion should is negligible.
-Change the noise power to 1265000 (approx. 15dB SNR), the voice should be still comprehensible.
-Change the noise power to 400000 (approx. 10dB SNR), voice will come through.
-Now change the rate\_index to the convolutional encoder/decoder to 6 (1/4), now the the voice should be comprehensible again. 
+\begin{enumerate}
+ \item Run the waveform and press the ``Push to Talk'' button while talking at the microphone. You should hear your voice from the speakers. Note that the CVSD encoding used has an inherent distorsion. At 400000 noise power (20dB SNR) the any channel distorsion should be negligible.
+\item Change the noise power to 1265000 (approx. 15dB SNR), the voice should be still comprehensible.
+\item Change the noise power to 400000 (approx. 10dB SNR), the voice may not come through.
+\item Now change the rate\_index to the convolutional encoder/decoder to 6 (1/4), now the the voice should be comprehensible again.
+\end{enumerate}
+
+ 
 
 \subsection{Step 2}
@@ -206 +212 @@
 \item DigitalModulator1.symbolsOut $\rightarrow$ FrameAssembler1.SymbolsIn
 \item FrameAssembler1.FrameSymbolsOut $\rightarrow$ amplifier1.datain
-\item amplifer1.dataout $\rightarrow$ Channel1.data\_in
+\item amplifer1.dataout $\rightarrow$ Interpolator1.inData
+\item Interpolator1.outData  $\rightarrow$ Channel1.data\_in
 \item Channel1.data\_out $\rightarrow$ Decimator1.outData
 \item Decimator1.outData $\rightarrow$ AutomaticGainControl1.data\_in
@@ -217 +224 @@
 \subsubsection{Component Properties}
 For each component set the listed properties. For the components that are not listed, used the properties from the previous step.
+
+\paragraph{Conv\_Enc1 and Conv\_Dec1}
+\begin{verbatim}
+mode=1
+rate_index=3
+\end{verbatim} 
+
 \paragraph{FrameAssembler1}
 \begin{verbatim}
@@ -253 +267 @@
 \end{verbatim}
 
+\paragraph{Channel1}
+\begin{verbatim}
+AWGN Noise Power=900000
+Fading type=None
+\end{verbatim}
+
 \subsection{Step 3}
 \osfigvs{blockdiagram3}{Block Diagram}{0.6}
-
+\subsubsection{Waveform Testing}
+\begin{enumerate}
+ \item Run the waveform and press the ``Push to Talk'' button while talking at the microphone. You should hear your voice from the speakers. The SNR should be about 20dB.
+\item Change the noise power to 2846250 (approx. 15dB SNR), the voice should be still comprehensible.
+\item Change the noise power to 9000000 (approx. 10dB SNR), the voice should still come through, the matched filtering improves the SNR.
 \subsection{Building the waveform}
 \osfig{waveformOEF}{OEF Waveform Structure}
@@ -383 +407 @@
 DemodScheme=QPSK
 \end{verbatim}
+
+\subsubsection{Waveform Testing}
+\begin{enumerate}
+ \item Run the waveform in two separate PCs and press the ``Push to Talk'' button while talking at the microphone. You should hear your voice from the other other computer. The voice delay should be minimum compared to the last steps.
 \end{document}