cordic.h 1.75 KB
 Arend van Spriel committed Jun 03, 2011 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 ``````/* * Copyright (c) 2011 Broadcom Corporation * * Permission to use, copy, modify, and/or distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #ifndef __CORDIC_H_ #define __CORDIC_H_ #include /** * struct cordic_iq - i/q coordinate. * * @i: real part of coordinate (in phase). * @q: imaginary part of coordinate (quadrature). */ struct cordic_iq { s32 i; s32 q; }; /** * cordic_calc_iq() - calculates the i/q coordinate for given angle. * * @theta: angle in degrees for which i/q coordinate is to be calculated. * @coord: function output parameter holding the i/q coordinate. * * The function calculates the i/q coordinate for a given angle using `````` Michael Witten committed Oct 29, 2011 39 `````` * CORDIC algorithm. The coordinate consists of a real (i) and an `````` Arend van Spriel committed Jun 03, 2011 40 41 42 43 44 45 46 47 48 `````` * imaginary (q) part. The real part is essentially the cosine of the * angle and the imaginary part is the sine of the angle. The returned * values are scaled by 2^16 for precision. The range for theta is * for -180 degrees to +180 degrees. Passed values outside this range are * converted before doing the actual calculation. */ struct cordic_iq cordic_calc_iq(s32 theta); #endif /* __CORDIC_H_ */``````