Cedric Roux
56c66c09aa
Pre-ci test passed git-svn-id: http://svn.eurecom.fr/openair4G/trunk@4000 818b1a75-f10b-46b9-bf7c-635c3b92a50f
36 lines
769 B
C
36 lines
769 B
C
/******************************
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* file: angle.c
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* purpose: compute the angle of a 8 bit complex number
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* author: florian.kaltenberger@eurecom.fr
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* date: 22.9.2009
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*******************************/
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#include "costable.h"
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#include "defs.h"
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unsigned int angle(struct complex16 perror) {
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int a;
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// a = atan(perror.i/perror.r);
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//since perror is supposed to be on the unit circle, we can also compute a by
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if (perror.i>=0) {
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if (perror.r>=0)
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a = acostable[min(perror.r,255)];
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else
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a = 32768-acostable[min(-perror.r,255)];
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//a = asin(perror.i);
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} else {
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if (perror.r>=0)
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a = 65536-acostable[min(perror.r,255)];
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else
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a = 32768+acostable[min(-perror.r,255)];
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//a = 2*PI-asin(perror.i);
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}
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return a;
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}
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