/******************************************************************************* OpenAirInterface Copyright(c) 1999 - 2014 Eurecom OpenAirInterface is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. OpenAirInterface is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenAirInterface.The full GNU General Public License is included in this distribution in the file called "COPYING". If not, see <http://www.gnu.org/licenses/>. Contact Information OpenAirInterface Admin: openair_admin@eurecom.fr OpenAirInterface Tech : openair_tech@eurecom.fr OpenAirInterface Dev : openair4g-devel@lists.eurecom.fr Address : Eurecom, Campus SophiaTech, 450 Route des Chappes, CS 50193 - 06904 Biot Sophia Antipolis cedex, FRANCE *******************************************************************************/ //#define DEBUG_DAC 1 #include <math.h> #include <stdio.h> #include "PHY/TOOLS/defs.h" void dac(double **s_re, double **s_im, uint32_t **input, uint32_t input_offset, uint32_t nb_tx_antennas, uint32_t length, double amp_dBm, uint8_t B, uint32_t meas_length, uint32_t meas_offset) { int i; int aa; double V=0.0,amp; for (i=0; i<length; i++) { for (aa=0; aa<nb_tx_antennas; aa++) { s_re[aa][i] = ((double)(((short *)input[aa]))[((i+input_offset)<<1)])/(1<<(B-1)); s_im[aa][i] = ((double)(((short *)input[aa]))[((i+input_offset)<<1)+1])/(1<<(B-1)); } } for (i=meas_offset; i<meas_offset+meas_length; i++) { for (aa=0; aa<nb_tx_antennas; aa++) { V= V + (s_re[aa][i]*s_re[aa][i]) + (s_im[aa][i]*s_im[aa][i]); } } V /= (meas_length); #ifdef DEBUG_DAC printf("DAC: 10*log10(V)=%f (%f)\n",10*log10(V),V); #endif if (V) { amp = pow(10.0,.1*amp_dBm)/V; amp = sqrt(amp); } else { amp = 1; } for (i=0; i<length; i++) { for (aa=0; aa<nb_tx_antennas; aa++) { s_re[aa][i] *= amp; s_im[aa][i] *= amp; } } } double dac_fixed_gain(double **s_re, double **s_im, uint32_t **input, uint32_t input_offset, uint32_t nb_tx_antennas, uint32_t length, uint32_t input_offset_meas, uint32_t length_meas, uint8_t B, double txpwr_dBm, int NB_RE) { int i; int aa; double amp,amp1; amp = //sqrt(NB_RE)*pow(10.0,.05*txpwr_dBm)/sqrt(nb_tx_antennas); //this is amp per tx antenna pow(10.0,.05*txpwr_dBm)/sqrt(nb_tx_antennas); //this is amp per tx antenna amp1 = 0; for (aa=0; aa<nb_tx_antennas; aa++) { amp1 += sqrt((double)signal_energy((int32_t*)&input[aa][input_offset_meas],length_meas)/NB_RE); } amp1/=nb_tx_antennas; // printf("DAC: amp1 %f dB (%d,%d), tx_power %f\n",20*log10(amp1),input_offset,input_offset_meas,txpwr_dBm); /* if (nb_tx_antennas==2) amp1 = AMP/2; else if (nb_tx_antennas==4) amp1 = ((AMP*ONE_OVER_SQRT2_Q15)>>16); else //assume (nb_tx_antennas==1) amp1 = ((AMP*ONE_OVER_SQRT2_Q15)>>15); amp1 = amp1*sqrt(512.0/300.0); //account for loss due to null carriers //printf("DL: amp1 %f dB (%d,%d), tx_power %f\n",20*log10(amp1),input_offset,input_offset_meas,txpwr_dBm); */ for (i=0; i<length; i++) { for (aa=0; aa<nb_tx_antennas; aa++) { s_re[aa][i] = amp*((double)(((short *)input[aa]))[((i+input_offset)<<1)])/amp1; ///(1<<(B-1)); s_im[aa][i] = amp*((double)(((short *)input[aa]))[((i+input_offset)<<1)+1])/amp1; ///(1<<(B-1)); } } // printf("ener %e\n",signal_energy_fp(s_re,s_im,nb_tx_antennas,length,0)); return(signal_energy_fp(s_re,s_im,nb_tx_antennas,length_meas,0)/NB_RE); }