rfm_space_model.c

无线传感器网络操作系统源代码

/*                                                                      tab:4
 *
 *
 * "Copyright (c) 2001 and The Regents of the University 
 * of California.  All rights reserved.
 *
 * Permission to use, copy, modify, and distribute this software and its
 * documentation for any purpose, without fee, and without written agreement is
 * hereby granted, provided that the above copyright notice and the following
 * two paragraphs appear in all copies of this software.
 * 
 * IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR
 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT
 * OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF
 * CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 * THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
 * ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATION TO
 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS."
 *
 * Authors:             Philip Levis
 *
 */

/*
 *   FILE: rfm_space_model.c
 * AUTHOR: pal
 *   DESC: Euclidean space model for RF connectivity
 */

#include "rfm_space_model.h"
#include "tossim.h"

#include <stdlib.h>
#include <stdio.h>
#include <math.h>

#define MAX_X ((double) 500.0)
#define MAX_Y ((double) 500.0)

double pot_settings[] = {
  999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9,
  999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9,
  999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9,
  999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9,
  999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9,

  999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9,
  999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9, 999.9,
  800.0, 600.0, 400.0, 200.0, 100.0, 50.0, 10.0, 0.0, 0.0, 0.0, // 70-76
  0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
  0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,

  0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
  0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
  0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
  0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
  0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
  
  0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
  0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
  0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
  0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
  0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0
};

typedef struct {
  double x;
  double y;
} pointXY;

typedef void(*positionFunction)(int, long long);

int isTransmitting[TOSNODES]; // Whether the mote was transmitting
int had_transmitted[TOSNODES][TOSNODES]; // [i][j]: Whether i transmitted to j
int radio_active[TOSNODES];

pointXY positions[TOSNODES];
positionFunction functions[TOSNODES];

void seed_positions();
void compute_connectivity(int moteID);
void step(int moteID, long long time);

void rfm_space_init() {
  int i, j;
  for (i = 0; i < tos_state.num_nodes; i++) {
    isTransmitting[i] = 0;
    radio_active[i] = 0;
    functions[i] = step;;
    for (j = 0; j < tos_state.num_nodes; j++) {
      had_transmitted[i][j] = 0;
    }
  }
  seed_positions();
}

void rfm_space_transmit(int moteID, char bit) {
  int i;
  functions[moteID](moteID, tos_state.tos_time);
  isTransmitting[moteID] = bit;
  if (bit) {
    compute_connectivity(moteID);
    for (i = 0; i < tos_state.num_nodes; i++) {
      if (had_transmitted[moteID][i]) {
	radio_active[i]++;
      }
    }
  }
}

void rfm_space_stop_transmit(int moteID) {
  if (isTransmitting[moteID]) {
    int i;
    isTransmitting[moteID] = 0;
    for (i = 0; i < tos_state.num_nodes; i++) {
      if (had_transmitted[moteID][i]) {
	radio_active[i]--;
      }
    }
  }
}

char rfm_space_hears(int moteID) {
  return (radio_active[moteID] > 0)? 1:0;
}

rfm_model* create_space_model() {
  rfm_model* model = (rfm_model*)malloc(sizeof(rfm_model));

  model->init = rfm_space_init;
  model->transmit = rfm_space_transmit;
  model->stop_transmit = rfm_space_stop_transmit;
  model->hears = rfm_space_hears;

  return model;
}

void seed_positions() {
  int i;
  for (i = 0; i < tos_state.num_nodes; i++) {
    double x = ((double)(rand() % 1000) / 1000.0) * MAX_X;
    double y = ((double)(rand() % 1000) / 1000.0) * MAX_Y;
    
    positions[i].x = x;
    positions[i].y = y;
  }
}



void step(int moteID, long long time) {
  double x = ((double)(rand() % 1000) / 1000.0);
  double y = ((double)(rand() % 1000) / 1000.0); 

  x /= 500.0;
  y /= 500.0;
  
  x += positions[moteID].x;
  y += positions[moteID].y;
    
  if (x < MAX_X && x > 0.0) {
    positions[moteID].x = x;
  }
  if (y < MAX_Y && y > 0.0) {
    positions[moteID].y = y;
  }
}

void compute_connectivity(int moteID) {
  int j;
  for (j = 0; j < tos_state.num_nodes; j++) {
    if (j != moteID) {
      double distance, x, y;
      x = positions[moteID].x - positions[j].x;
      x = x * x;

      y = positions[moteID].y - positions[j].y;
      y = y * y;
      
      distance = sqrt(x + y);

      if (distance < pot_settings[(int)tos_state.node_state[moteID].pot_setting]) {
	had_transmitted[moteID][j] = 1;
      }
      else {
	had_transmitted[moteID][j] = 0;
      }
    }
  }
}