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Ajout du tableau comparatif entre Fir compiler et Oscimp
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ifcs2018_journal.tex
| ... | ... | @@ -120,7 +120,7 @@ |
| 120 | 120 | signals, High Level Synthesis (HLS) languages \cite{kasbah2008multigrid} are not considered but |
| 121 | 121 | the problem is tackled at the Very-high-speed-integrated-circuit Hardware Description Language |
| 122 | 122 | (VHDL) level. |
| 123 | -{\color{red}Since latency is not an issue in a openloop phase noise characterization instrument, | |
| 123 | +{\color{red}Since latency is not an issue in a openloop phase noise characterization instrument, | |
| 124 | 124 | the large |
| 125 | 125 | numbre of taps in the FIR, as opposed to the shorter Infinite Impulse Response (IIR) filter, |
| 126 | 126 | is not considered as an issue as would be in a closed loop system.} % r2.4 |
| ... | ... | @@ -144,7 +144,7 @@ |
| 144 | 144 | relation between number of fiter taps and quantization, Fig. \ref{float_vs_int} exhibits |
| 145 | 145 | a 128-coefficient FIR bandpass filter designed using floating point numbers (blue). Upon |
| 146 | 146 | quantization on 6~bit integers, 60 of the 128~coefficients in the beginning and end of the |
| 147 | -taps become null, {\color{red}making the large number of coefficients irrelevant: processing | |
| 147 | +taps become null, {\color{red}making the large number of coefficients irrelevant: processing | |
| 148 | 148 | resources % r1.1 |
| 149 | 149 | are hence saved by shrinking the filter length.} This tradeoff aimed at minimizing resources |
| 150 | 150 | to reach a given rejection level, or maximizing out of band rejection for a given computational |
| 151 | 151 | |
| ... | ... | @@ -197,10 +197,10 @@ |
| 197 | 197 | |
| 198 | 198 | {\color{red} |
| 199 | 199 | The first step of our approach is to model the DSP chain. Since we aim at only optimizing % r1.3 |
| 200 | -the filtering part of the signal processing chain, we have not included the PRN generator or the | |
| 201 | -ADC in the model: the input data size and rate are considered fixed and defined by the hardware. | |
| 200 | +the filtering part of the signal processing chain, we have not included the PRN generator or the | |
| 201 | +ADC in the model: the input data size and rate are considered fixed and defined by the hardware. | |
| 202 | 202 | The filtering can be done in two ways, either by considering a single monolithic FIR filter |
| 203 | -requiring many coefficients to reach the targeted noise rejection ratio, or by | |
| 203 | +requiring many coefficients to reach the targeted noise rejection ratio, or by | |
| 204 | 204 | cascading multiple FIR filters, each with fewer coefficients than found in the monolithic filter.} |
| 205 | 205 | |
| 206 | 206 | After each filter we leave the possibility of shifting the filtered data to consume |
| ... | ... | @@ -298,7 +298,7 @@ |
| 298 | 298 | Our criterion to compute the filter rejection considers |
| 299 | 299 | % r2.8 et r2.2 r2.3 |
| 300 | 300 | the maximum magnitude within the stopband, to which the {\color{red}sum of the absolute values |
| 301 | -within the passband is subtracted to avoid filters with excessive ripples}. With this | |
| 301 | +within the passband is subtracted to avoid filters with excessive ripples}. With this | |
| 302 | 302 | criterion, we meet the expected rejection capability of low pass filters as shown in figure~\ref{fig:custom_criterion}. |
| 303 | 303 | |
| 304 | 304 | % \begin{figure} |
| ... | ... | @@ -1010,6 +1010,25 @@ |
| 1010 | 1010 | needed in the previous section. Indeed the worst time in this case is only 17~minutes, |
| 1011 | 1011 | compared to 3~days in the previous section: this problem is more easily solved than the |
| 1012 | 1012 | previous one. |
| 1013 | + | |
| 1014 | +\renewcommand{\arraystretch}{1.2} | |
| 1015 | +\begin{table} | |
| 1016 | +\centering | |
| 1017 | +\caption{Resource consumption compared between the FIR Compiler from Xilinx and our FIR block} | |
| 1018 | +\label{tbl:area_time_comp} | |
| 1019 | +\begin{tabular}{|c|c|c|c|c|c|c|} | |
| 1020 | +\hline | |
| 1021 | +\multirow{2}{*}{} & \multicolumn{3}{c|}{Xilinx} & \multicolumn{3}{c|}{Our FIR block} \\ \cline{2-7} | |
| 1022 | + & LUT & BRAM & DSP & LUT & BRAM & DSP \\ \hline | |
| 1023 | +MAX/500 & 177 & 0 & 21 & 249 & 1 & 21 \\ \hline | |
| 1024 | +MAX/1000 & 306 & 0 & 37 & 453 & 1 & 37 \\ \hline | |
| 1025 | +MAX/1500 & 418 & 0 & 47 & 627 & 1 & 47 \\ \hline | |
| 1026 | +MIN/40 & 225 & 0 & 27 & 347 & 1 & 27 \\ \hline | |
| 1027 | +MIN/60 & 322 & 0 & 39 & 334 & 1 & 39 \\ \hline | |
| 1028 | +MIN/80 & 482 & 0 & 55 & 772 & 1 & 55 \\ \hline | |
| 1029 | +\end{tabular} | |
| 1030 | +\end{table} | |
| 1031 | +\renewcommand{\arraystretch}{1} | |
| 1013 | 1032 | |
| 1014 | 1033 | \section{Conclusion} |
| 1015 | 1034 |