mirror of https://github.com/PentHertz/srsLTE.git
138 lines
2.7 KiB
C
138 lines
2.7 KiB
C
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#include <stdio.h>
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#include <stdlib.h>
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#include <strings.h>
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#include <unistd.h>
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#include <math.h>
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#include <time.h>
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#include <complex.h>
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#include "liblte/phy/utils/dft.h"
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typedef _Complex float cf_t;
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int N = 256;
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bool forward = true;
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bool mirror = false;
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bool norm = false;
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bool dc = false;
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void usage(char *prog) {
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printf("Usage: %s\n", prog);
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printf("\t-N Transform size [Default 256]\n");
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printf("\t-b Backwards transform first [Default Forwards]\n");
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printf("\t-m Mirror the transform freq bins [Default false]\n");
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printf("\t-n Normalize the transform output [Default false]\n");
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printf("\t-d Handle insertion/removal of null DC carrier internally [Default false]\n");
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}
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void parse_args(int argc, char **argv) {
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int opt;
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while ((opt = getopt(argc, argv, "Nbmnd")) != -1) {
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switch (opt) {
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case 'N':
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N = atoi(argv[optind]);
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break;
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case 'b':
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forward = false;
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break;
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case 'm':
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mirror = true;
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break;
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case 'n':
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norm = true;
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break;
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case 'd':
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dc = true;
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break;
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default:
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usage(argv[0]);
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exit(-1);
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}
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}
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}
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void print(cf_t* in, int len)
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{
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for(int i=0;i<len;i++)
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{
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float re = crealf(in[i]);
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float im = cimagf(in[i]);
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printf("%f+%fi, ", re, im);
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}
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printf("\n\n");
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}
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int test_dft(cf_t* in){
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int res = 0;
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dft_plan_t plan;
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if(forward){
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dft_plan(&plan, N, FORWARD, COMPLEX);
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} else {
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dft_plan(&plan, N, BACKWARD, COMPLEX);
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}
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dft_plan_set_mirror(&plan, mirror);
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dft_plan_set_norm(&plan, norm);
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dft_plan_set_dc(&plan, dc);
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cf_t* out1 = malloc(sizeof(cf_t)*N);
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cf_t* out2 = malloc(sizeof(cf_t)*N);
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bzero(out1, sizeof(cf_t)*N);
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bzero(out2, sizeof(cf_t)*N);
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print(in, N);
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dft_run(&plan, in, out1);
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print(out1, N);
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dft_plan_t plan_rev;
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if(!forward){
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dft_plan(&plan_rev, N, FORWARD, COMPLEX);
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} else {
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dft_plan(&plan_rev, N, BACKWARD, COMPLEX);
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}
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dft_plan_set_mirror(&plan_rev, mirror);
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dft_plan_set_norm(&plan_rev, norm);
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dft_plan_set_dc(&plan_rev, dc);
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dft_run(&plan_rev, out1, out2);
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print(out2, N);
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if(!norm){
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cf_t n = N+0*I;
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for(int i=0;i<N;i++)
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out2[i] /= n;
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}
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for(int i=0;i<N;i++){
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float diff = cabsf(in[i] - out2[i]);
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if(diff > 0.01)
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res = -1;
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}
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dft_plan_free(&plan);
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dft_plan_free(&plan_rev);
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free(out1);
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free(out2);
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return res;
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}
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int main(int argc, char **argv) {
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parse_args(argc, argv);
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cf_t* in = malloc(sizeof(cf_t)*N);
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bzero(in, sizeof(cf_t)*N);
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for(int i=1;i<N-1;i++)
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{
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float re = 100*(float)rand()/RAND_MAX;
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float im = 100*(float)rand()/RAND_MAX;
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in[i] = re + im*I;
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}
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if(test_dft(in) != 0)
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return -1;
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free(in);
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printf("Done\n");
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exit(0);
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}
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