radio_bs.c

软件无线电的平台

/***************************************************************************
               radio_bs.c  -  LDPC BS
                            -------------------
    begin                :  02/10/30
    authors              :  Linus Gasser
    emails               :  [e-mail]
 ***************************************************************************/

/***************************************************************************
                                 Changes
                                 -------
 date - name - description
 02/10/30 - ineiti - begin
 02/11/04 - ineiti - no msgqs...
 03/02/27 - ineiti - simplified to only two slots: BCH and RACH
 03/04/04 - ineiti - uses synch-macro
 03/04/28 - ineiti - use mode-config of test_data_rcv rather than clear
 03/04/28 - ineiti - use mafi-config of decode so it can calculate it's own
                     SNR
 03/05/09 - ineiti - uses done-stats of decode to know when it's safe to
                     start another round of decoding
 04/03/20 - ineiti - used make_thread instead of send_msg
 04/04/20 - ineiti - cleaned up finishing of the module
 **************************************************************************/

/***************************************************************************
 *                                                                         *
 *   This program 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 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/


/**
 * Make a simple BS
 *
 * Function:
 * - emit sync
 * - listen to RACh
 */

#include "system.h"
#include "sdb.h"
#include "stfa.h"
#include "antenna.h"
#include "std.h"
#include "debugging.h"
#include "spc.h"
#include "../simple_radio.h"
#include "chain.h"
#include "../common.h"


#define DBG_LVL 0

#define SNR_SWEEP_MIN -10
#ifdef USER_SPACE
#define SNR_SWEEP_STEP .1
#else
#define SNR_SWEEP_STEP .005
#endif
#define SNR_SWEEP_MAX 10
#define ANTENNA 0
#define MIN_AMP 3
#define TIME_TO_LINUX 50

#ifdef USER_SPACE
#define gethrtime() ( count * TIME_TO_LINUX * 1000000 )
#endif

swr_sdb_id
stfa,
energy,
sch,
decode,
sink,
mafi,
received_data,
rand_u8;
struct chain_t *ch_bch, *ch_rach, *ch_rnd;
struct slot_bch bch_data;

int slots_per_frame, looping, count;
double target_snr;

int callback( int msg, void *data, swr_sdb_id ret_id ) {

  // Do a 'sweep' on the snr
  target_snr += SNR_SWEEP_STEP;
  if ( target_snr > SNR_SWEEP_MAX ) {
    target_snr = SNR_SWEEP_MIN;
  }
  PR_DBG( 4, "target_snr: %s%i.%i\n", swr_ftosii( target_snr ) );
  swr_sdb_set_config_double( sch, "target_snr0", target_snr );

  return 0;
}


void *start_it( void *arg ) {
  looping = 1;

  usleep( 100000 );

  stfa = swr_sdb_instantiate_name( "stfa" );

  PR( "Setting up BCh on slot 0\n" );
  ch_bch = swr_chain_create( NEW_SPC_VAR( "sch_send", sch ),
                             NEW_SPC( "mapper" ),
                             NEW_SPC( "spread" ),
                             NEW_SPC( "midamble" ),
                             NEW_SPC( "synch_send" ),
                             NEW_SPC( "rrc" ),
                             OLD_SPC_IN( stfa, 0 ),
			     CHAIN_END );
  swr_stfa_notice_sdb( stfa, 0, sch );
  swr_sdb_set_config_int( sch, "id0", 0x1234 );
  swr_sdb_set_config_int( sch, "uplinks0", 2 );
  swr_sdb_set_config_pointer( sch, "data_usr", &bch_data );
  swr_sdb_set_config_int( sch, "len_usr", sizeof( struct slot_bch ) );
  target_snr = SNR_SWEEP_MIN;
  // 1 -> 0.25
  // 2 -> 0.5
  // 3 -> 0.75
  bch_data.ldpc_code_id = 2;

  PR( "Setting up LDPC slot 1\n" );
  ch_rach = swr_chain_create(
              OLD_SPC_OUT( stfa, 1 ),
              NEW_SPC_VAR( "energy", energy ),
              NEW_SPC_VAR( "matched_filter", mafi ),
              NEW_SPC_VAR( "ldpc_decode", decode ),
              NEW_SPC_VAR( "test_data_rcv", received_data ),
              CHAIN_END );
  make_thread( energy );
  swr_sdb_set_config_int( sch, "mafi0", mafi );
  swr_sdb_set_config_int( decode, "mafi", mafi );
  // Reset counters to zero after each run
  swr_sdb_set_config_int( received_data, "mode", 1 );
  // Only wait for input 0
  swr_sdb_set_config_int( received_data, "wait", 1 );

  ch_rnd = swr_chain_create( NEW_SPC_VAR( "random", rand_u8 ),
                             OLD_SPC_IN( received_data, 1 ),
                             CHAIN_END );
  swr_sdb_set_config_int( rand_u8, "seed", 0x1234 );
  swr_sdb_set_config_int( rand_u8, "mode", 1 );

  // set up the ldpc-decoder
  swr_sdb_set_config_int( decode, "ldpc_code_id", bch_data.ldpc_code_id );
  swr_sdb_set_config_int( decode, "iterations", 30 );
  swr_sdb_set_config_int( decode, "channel_type", 2 );
  count = 0;
  // And produce random-data for the test_data_rcv
  call_module( rand_u8 );


  swr_stfa_notice_func( stfa, 10, callback );

  // Start the transmission
  swr_stfa_go( stfa );

  while ( looping++ ) {
    usleep( 1000000 );

    if ( looping > 30 ) {
      //      looping = 0;
    }
  }

  swr_stfa_stop( stfa );

  usleep( 100000 );

  return 0;
}


struct thread start;

/**
 * This function is called upon "insmod" and is used to register the
 * different parts of the module to the SPM.
 */
int um_module_init(void) {

  MOD_INC_USE_COUNT;
  looping = 0;
  ch_bch = NULL;
  ch_rach = NULL;
  if ( swr_thread_init( &start, start_it, NULL ) ) {
    goto rrc_no_thread;
  }
  MOD_DEC_USE_COUNT;
  return 0;

rrc_no_thread:
  PR_DBG( 0, "Couldn't init thread\n" );
  MOD_DEC_USE_COUNT;
  return -1;
}



void um_module_exit( void ) {
  looping = 0;

  swr_thread_free( &start, NULL );
  PR_DBG( 0, "deleting everything\n" );
  swr_chain_destroy( ch_rnd );
  swr_chain_destroy( ch_bch );
  swr_chain_destroy( ch_rach );
  swr_sdb_destroy( stfa );
}


module_init( um_module_init );
module_exit( um_module_exit );