/* wlan_propdel.ps.c */                                                       /* Modified for IEEE802.11										*//* Propagation delay model for radio link Transceiver Pipeline 	*//****************************************//*		  Copyright (c) 1993			*//*			by MIL 3, Inc.				*//*		(A Delaware Corporation)		*//*	3400 International Drive,  N.W.		*//*		Washington, D.C., U.S.A.		*//*			All Rights Reserved.		*//****************************************/#include <opnet.h>/***** constants *****//* propagation velocity of radio signal (m/s) */#define	PROP_VELOCITY	3.0E+08#define DEBUG 0/* The variable defining a maximum range across which the station can communicate (meters)	*/ static double wlan_max_distance = OPC_DBL_INFINITY;/***** pipeline procedure *****/#if defined (__cplusplus)extern "C"#endifvoidwlan_propdel (pkptr)	Packet*		pkptr;	{	double		start_prop_delay, end_prop_delay;	double		start_prop_distance, end_prop_distance;	Objid       rx_node_id, tx_node_id;	int         rx_addr;	double      rx_x, rx_y, tx_x, tx_y, dist_rx_tx;	/** Compute the propagation delay separating the	**/	/** radio transmitter from the radio receiver.		**/	FIN (wlan_propdel (pkptr));	rx_node_id = op_topo_parent(op_td_get_int (pkptr, OPC_TDA_RA_RX_OBJID));	op_ima_obj_attr_get(rx_node_id,"x position",&rx_x);	rx_x = (double) rx_x;	op_ima_obj_attr_get(rx_node_id,"y position",&rx_y);	rx_y = (double) rx_y;	op_ima_obj_attr_get(rx_node_id,"wlan_mac.station_address",&rx_addr);		tx_node_id = op_topo_parent(op_td_get_int (pkptr, OPC_TDA_RA_TX_OBJID));	op_ima_obj_attr_get(tx_node_id,"x position",&tx_x);	tx_x = (double) tx_x;	op_ima_obj_attr_get(tx_node_id,"y position",&tx_y);	tx_y = (double) tx_y;	dist_rx_tx= sqrt((tx_x-rx_x)*(tx_x-rx_x) + (rx_y-tx_y)*(rx_y-tx_y));	/* Get the start distance between transmitter and receiver. */	start_prop_distance = op_td_get_dbl (pkptr, OPC_TDA_RA_START_DIST);	/* Get the end distance between transmitter and receiver. */	end_prop_distance = op_td_get_dbl (pkptr, OPC_TDA_RA_END_DIST);	if(DEBUG) printf("@ node %d :: dist = %f  ", rx_addr,start_prop_distance);	/* Compute propagation delay to start of reception. */	//start_prop_delay = start_prop_distance / PROP_VELOCITY;	start_prop_delay = dist_rx_tx / PROP_VELOCITY;	/* Compute propagation delay to end of reception. */	//end_prop_delay = end_prop_distance / PROP_VELOCITY;	end_prop_delay = dist_rx_tx / PROP_VELOCITY;	/* If the maximum transmission range of the station is not already set then extract	*/	/* it from the user defined simulation attribute.									*/	if (wlan_max_distance == OPC_DBL_INFINITY)		{		if (op_ima_sim_attr_exists ("Wireless LAN Range (meters)") == OPC_TRUE)			{			op_ima_sim_attr_get (OPC_IMA_DOUBLE, "Wireless LAN Range (meters)", &wlan_max_distance);			}		}	//printf("\n|-------------------------------------------------|\n");	//op_pk_print(pkptr);    /* If the starting and ending propagation distance is more than the maximum transmission	*/	/* range then discard the packet in the pipeline stage. This will model the physical		*/	/* transmission boundary of a wireless station.												*/ 	if (end_prop_distance > wlan_max_distance || start_prop_distance > wlan_max_distance)		{		if(DEBUG) printf("- IGNORED\n");		/* Discard the packet if the destination is more than the specified range	*/		op_td_set_int (pkptr, OPC_TDA_RA_MATCH_STATUS, OPC_TDA_RA_MATCH_IGNORE);		}	else if(DEBUG)		printf("- ACCEPTED\n");    /* Place both propagation delays in packet transmission data attributes. */	op_td_set_dbl (pkptr, OPC_TDA_RA_START_PROPDEL, start_prop_delay);	op_td_set_dbl (pkptr, OPC_TDA_RA_END_PROPDEL,   end_prop_delay);	FOUT;	}