From ec91065abc62cf760eae8829a63d8bf8af8f48e2 Mon Sep 17 00:00:00 2001 From: Arthur HUGEAT Date: Tue, 30 Jul 2019 10:48:54 +0200 Subject: [PATCH] Ajout du tableau comparatif entre Fir compiler et Oscimp --- ifcs2018_journal.tex | 31 +++++++++++++++++++++++++------ 1 file changed, 25 insertions(+), 6 deletions(-) diff --git a/ifcs2018_journal.tex b/ifcs2018_journal.tex index ebf1932..7e87394 100644 --- a/ifcs2018_journal.tex +++ b/ifcs2018_journal.tex @@ -120,7 +120,7 @@ processing (as opposed to First-In, First-Out FIFO memory batch processing) of r signals, High Level Synthesis (HLS) languages \cite{kasbah2008multigrid} are not considered but the problem is tackled at the Very-high-speed-integrated-circuit Hardware Description Language (VHDL) level. -{\color{red}Since latency is not an issue in a openloop phase noise characterization instrument, +{\color{red}Since latency is not an issue in a openloop phase noise characterization instrument, the large numbre of taps in the FIR, as opposed to the shorter Infinite Impulse Response (IIR) filter, is not considered as an issue as would be in a closed loop system.} % r2.4 @@ -144,7 +144,7 @@ integer operations is not trivial. As an illustration of the issue related to th relation between number of fiter taps and quantization, Fig. \ref{float_vs_int} exhibits a 128-coefficient FIR bandpass filter designed using floating point numbers (blue). Upon quantization on 6~bit integers, 60 of the 128~coefficients in the beginning and end of the -taps become null, {\color{red}making the large number of coefficients irrelevant: processing +taps become null, {\color{red}making the large number of coefficients irrelevant: processing resources % r1.1 are hence saved by shrinking the filter length.} This tradeoff aimed at minimizing resources to reach a given rejection level, or maximizing out of band rejection for a given computational @@ -197,10 +197,10 @@ when implementing a solution minimizing resource occupation. {\color{red} The first step of our approach is to model the DSP chain. Since we aim at only optimizing % r1.3 -the filtering part of the signal processing chain, we have not included the PRN generator or the -ADC in the model: the input data size and rate are considered fixed and defined by the hardware. +the filtering part of the signal processing chain, we have not included the PRN generator or the +ADC in the model: the input data size and rate are considered fixed and defined by the hardware. The filtering can be done in two ways, either by considering a single monolithic FIR filter -requiring many coefficients to reach the targeted noise rejection ratio, or by +requiring many coefficients to reach the targeted noise rejection ratio, or by cascading multiple FIR filters, each with fewer coefficients than found in the monolithic filter.} After each filter we leave the possibility of shifting the filtered data to consume @@ -298,7 +298,7 @@ In the transition band, the behavior of the filter is left free, we only {\color Our criterion to compute the filter rejection considers % r2.8 et r2.2 r2.3 the maximum magnitude within the stopband, to which the {\color{red}sum of the absolute values -within the passband is subtracted to avoid filters with excessive ripples}. With this +within the passband is subtracted to avoid filters with excessive ripples}. With this criterion, we meet the expected rejection capability of low pass filters as shown in figure~\ref{fig:custom_criterion}. % \begin{figure} @@ -1011,6 +1011,25 @@ needed in the previous section. Indeed the worst time in this case is only 17~mi compared to 3~days in the previous section: this problem is more easily solved than the previous one. +\renewcommand{\arraystretch}{1.2} +\begin{table} +\centering +\caption{Resource consumption compared between the FIR Compiler from Xilinx and our FIR block} +\label{tbl:area_time_comp} +\begin{tabular}{|c|c|c|c|c|c|c|} +\hline +\multirow{2}{*}{} & \multicolumn{3}{c|}{Xilinx} & \multicolumn{3}{c|}{Our FIR block} \\ \cline{2-7} + & LUT & BRAM & DSP & LUT & BRAM & DSP \\ \hline +MAX/500 & 177 & 0 & 21 & 249 & 1 & 21 \\ \hline +MAX/1000 & 306 & 0 & 37 & 453 & 1 & 37 \\ \hline +MAX/1500 & 418 & 0 & 47 & 627 & 1 & 47 \\ \hline +MIN/40 & 225 & 0 & 27 & 347 & 1 & 27 \\ \hline +MIN/60 & 322 & 0 & 39 & 334 & 1 & 39 \\ \hline +MIN/80 & 482 & 0 & 55 & 772 & 1 & 55 \\ \hline +\end{tabular} +\end{table} +\renewcommand{\arraystretch}{1} + \section{Conclusion} We have proposed a new approach to schedule a set of signal processing blocks whose performances -- 2.16.4