gpr_wlan_mac.pr.c

opnet Ad hoc仿真源程序,自己构建的路由协议和网络模型

/* Process model C form file: gpr_wlan_mac.pr.c */
/* Portions of this file copyright 1992-2003 by OPNET Technologies, Inc. */



/* This variable carries the header into the object file */
const char gpr_wlan_mac_pr_c [] = "MIL_3_Tfile_Hdr_ 100A 30A op_runsim 7 42FB0CD7 42FB0CD7 1 zhangzhong jc 0 0 none none 0 0 none 0 0 0 0 0 0 0 0 8f3 1                                                                                                                                                                                                                                                                                                                                                                                                           ";
#include <string.h>



/* OPNET system definitions */
#include <opnet.h>



/* Header Block */

/** Include files **/

#include <math.h>
#include <string.h>
#include "oms_pr.h"
#include "oms_tan.h"
#include "oms_bgutil.h"
#include "wlan_support.h"
#include "oms_auto_addr_support.h"
#include "oms_dist_support.h"
#include "bridge_header.h"	
#include "prg_mapping.h"
#include <prg_geo.h>


/** Constants **/

/* Incoming statistics and stream wires.							*/
#define 	TRANSMITTER_BUSY_INSTAT		1
#define		LOW_LAYER_INPUT_STREAM		0
#define		LOW_LAYER_OUTPUT_STREAM		0

/* Flags to load different variables based on attribute settings.	*/
#define		WLAN_AP						1
#define		WLAN_STA					0

/* Flags to indicate the medium access mode (PCF/DCF).				*/
#define		PCF_ACTIVE					1
#define		PCF_INACTIVE				0

/* Special value indicating BSS identification is not used.			*/
#define		WLAN_BSSID_NOT_USED			-1

/* Special value indicating radio transceiver frequencies are set	*/
/* based on the BSS identification.									*/
#define 	WLAN_BSS_BASED_FREQ_USED	-1

/* Special value indicating that the number of back-off slots are	*/
/* not determined yet.												*/
#define		BACKOFF_SLOTS_UNSET			-1.0

/* Define a small value (= 1 psec), which will be used to recover	*/
/* from double arithmetic precision losts while doing time related	*/
/* precision sensitive computations.								*/
#define		PRECISION_RECOVERY			0.000000000001

/* Special value indicating BSS identification is currently unset.	*/
#define 	WLANC_BSS_ID_UNKNOWN		-2

/* Define the lowest data transmission rate supported by WLAN MAC.	*/
#define		LOWEST_TX_RATE				1000000.0 /* bits/sec */

/* Speed of light (m/s). 											*/
#define 	C							3.0E+08		

/* 16 times pi-squared. 											*/
#define 	SIXTEEN_PI_SQ				157.91367	

/* In the idle state, number of beacon intervals after which the STA will wake	*/
/* up to check if it is still connected, if scanning is based on beacon			*/
/* reliability. There are no interrupts pending in the idle state, therefore,	*/
/* it is possible that the STA's state may be set to "scan" from a pipeline		*/
/* state without the MAC becoming aware of the state change till a packet		*/
/* arrives from the higher layer. Hence, there is a need to schedule periodic	*/
/* interrupts when in IDLE.    													*/
#define WLANC_CONN_CHK_BEACON_MULT		5.0  

/* Period after which the STA will check for connectivity if scanning is		*/
/* distance based. 																*/
#define WLANC_CONN_CHK_DIST_INTERVAL	10.0

/* When in the SCAN state, the period that an STA will wait before trying a new	*/
/* channel. 																	*/
#define WLANC_NEW_SCAN_BEACON_MULT		2.5

/* Physical layer parameters used during roaming/channel scanning.				*/
#define	WLANC_CHANNEL_COUNT				11
#define	WLANC_FIRST_CHAN_MIN_FREQ		2401.0	/* MHz */
#define	WLANC_CHANNEL_BANDWIDTH			22.0	/* MHz */
#define	WLANC_CHANNEL_SPACING			5.0		/* MHz */
#define	WLANC_LAST_CHAN_MIN_FREQ		((WLANC_CHANNEL_COUNT - 1) * WLANC_CHANNEL_SPACING + WLANC_FIRST_CHAN_MIN_FREQ)
#define WLANC_CH_STEP_FOR_NO_OVERLAP	((int) ceil (WLANC_CHANNEL_BANDWIDTH / WLANC_CHANNEL_SPACING))	

/* When virtual scanning is used, two different thresholds are used to decide	*/
/* when the STA must start looking for a new AP, and when a new AP is			*/
/* considered acceptable. This brings in a "hysteresis" which ensures that the	*/
/* STA does not flip-flop rapidly between APs.                          		*/
#define WLANC_ROAM_SCAN_START_VIRTUAL_THRESH	rx_power_threshold
#define WLANC_ROAM_NEW_CONN_VIRTUAL_THRESH		(rx_power_threshold * 1.1)


/** Enumarated Types **/

/* Define the three possible values that a global variable takes				*/
/* to check and ensure that all the MAC modules are either BSS ID				*/
/* based or purely subnet based. The variable is initialized to					*/
/* Not_Set and the first wireless MAC process sets it to either					*/
/* Entire_Subnet (if BSS_Identifier is Not Used) or Bssid_Subnet				*/
/* (if the BSS_Identifier is set to some value other than Not					*/
/* Used).																		*/						  
typedef enum WlanT_Bssid_Approach
	{
	WlanC_Not_Set,						/* Type of network not set				*/
	WlanC_Entire_Subnet,				/* The network is a pure subnet			*/
	WlanC_Bss_Divided_Subnet			/* The network is a BSS based subnet	*/
	} WlanT_Bss_Identification_Approach;
 
/* Define interrupt codes for generating handling interrupts					*/
/* indicating changes in deference, frame timeout which infers         			*/
/* that the collision has occurred, random backoff and transmission 			*/
/* completion by the physical layer (self interrupts).							*/
typedef enum WlanT_Mac_Intrpt_Code
	{	
	WlanC_Deference_Off,  	/* Deference before frame transmission 				*/
	WlanC_Frame_Timeout,	/* No frame rcvd in set duration (infer collision)	*/
	WlanC_Backoff_Elapsed,  /* Backoff done before frame transmission			*/
	WlanC_CW_Elapsed,		/* Backoff done after successful frame transmission	*/	
	WlanC_Beacon_Tx_Time,	/* Time to transmit beacon frame                    */
	WlanC_Cfp_End,			/* End of the Contention free period 				*/
	WlanC_Scan_Timeout,		/* End of scan duration for given channel 			*/
	WlanC_AP_Check_Timeout	/* Time to check the connectivity status with the	*/
							/* current AP.										*/
	} WlanT_Mac_Intrpt_Code;

/* Defining codes for the physical layer characteristics type.					*/
typedef enum WlanT_Phy_Char_Code
	{
	WlanC_Frequency_Hopping,			
	WlanC_Direct_Sequence,				
	WlanC_Infra_Red					
	} WlanT_Phy_Char_Code;


/** Data Structures **/

/* Define a structure to maintain data fragments received by each 	  */
/* station for the purpose of reassembly (or defragmentation)		  */
typedef struct WlanT_Mac_Defragmentation_Buffer_Entry
	{		
	int			tx_station_address    ;/* Store the station address of transmitting station  		*/	 
	double		time_rcvd		      ;/* Store time the last fragment for this frame was received	*/ 
	Sbhandle	reassembly_buffer_ptr ;/* Store data fragments for a particular packet       		*/  		 
	} WlanT_Mac_Defragmentation_Buffer_Entry;

/* Define a structure to maintain a copy of each unique data frame      */
/* received by the station. This is done so that the station can    	*/
/* discard any additional copies of the frame received by it. 	   		*/
typedef struct WlanT_Mac_Duplicate_Buffer_Entry
	{	
	int         tx_station_address;  /* store the station address of transmitting station	*/
	int 		sequence_id		  ;  /* rcvd packet sequence id 						 	*/	
	int		    fragment_number	  ;  /* rcvd packet fragment number                      	*/	 
	} WlanT_Mac_Duplicate_Buffer_Entry;

/* This structure contains all the flags used in this process model to determine	*/
/* various conditions as mentioned in the comments for each flag					*/
typedef struct WlanT_Mac_Flags
	{
	Boolean 	data_frame_to_send; /* Flag to check when station needs to transmit.		*/ 
	Boolean     backoff_flag;  	    /* Backoff flag is set when either the collision is		*/
	                                /* inferred or the channel switched from busy to idle	*/
	Boolean		rts_sent;   		/* Flag to indicate that whether the Rts for this		*/
								    /* particular data frame is sent						*/
	Boolean		rcvd_bad_packet;	/* Flag to indicate that the received packet is bad		*/
    Boolean	    receiver_busy;		/* Set this flag if receiver busy stat is enabled		*/	
    Boolean	    transmitter_busy;	/* Set this flag if we are transmitting something.		*/	
	Boolean		wait_eifs_dur;		/* Set this flag if the station needs to wait for eifs	*/
									/* duration.											*/	
	Boolean		gateway_flag;		/* Set this flag if the station is a gateway.			*/
	Boolean		bridge_flag;		/* Set this flag if the station is a bridge				*/
	Boolean		immediate_xmt;		/* Set this flag if the new frame can be transmitted	*/
									/* without deferring.									*/
	Boolean		forced_bk_end;		/* Special case: resume with completion of back-off (or	*/
									/* CW) period regardless of receiver's status.			*/
	Boolean		cw_required;		/* Indicates that the MAC is in contention window		*/
									/* period following a successful transmission.			*/
	Boolean		perform_cw;			/* Flag that triggers backoff process for CW period.	*/
	Boolean		nav_updated;		/* Indicates a new NAV value since the last time when	*/
									/* self interrupt is scheduled for the end of deference.*/
	Boolean		collision;			/* Set this flag if a channel became busy while another	*/
									/* one busy.											*/
	Boolean		collided_packet;	/* Set this flag to drop the next received packet		*/
									/* because of collision.								*/
	Boolean		duration_zero;		/* Set this flag if duration should be zero in next ack	*/
	Boolean		ignore_busy;		/* Set this flag if the STA should ignore receiver busy	*/
	Boolean		tx_beacon;          /* Set this flag if time to send a beacon               */
	Boolean		tx_cf_end;          /* Set this flag if time to send a CF End frame         */
	Boolean		pcf_active;         /* Set this flag for AP if PCF is currently in effect	*/
	Boolean		polled;		        /* Set this flag if the station has received a poll     */
	Boolean		more_data;			/* Set this flag if must poll for more data (MSDU)		*/
	Boolean		more_frag;			/* Set this flag if must poll for more fragments		*/
	Boolean		pcf_side_traf;		/* Set this flag if the AP detects STA to STA traffic   */
	Boolean		active_poll;		/* Set this flag if an active poll is outstanding		*/
	} WlanT_Mac_Flags;

/* This structure contains the destination address to which the received */
/* data packet needs to be sent and the contents of the received packet  */
/* from the higher layer.												 */
typedef struct WlanT_Hld_List_Elem
	{
	double		time_rcvd;  			/* Time packet is received by the higher layer	*/
	int			destination_address; 	/* Station to which this packet needs to be sent*/
	Packet*     pkptr;				 	/* store packet contents  					  	*/
	} WlanT_Hld_List_Elem;

/* Information record for each BSS */
typedef struct bss_mapping_info
	{
	int 				bss_idx;
	int					ap_sta_addr;
	PrgT_Mapping_Handle sta_mapping_hndl;
	}WlanT_Bss_Mapping_Info;

/* Information record for each STA */
typedef struct sta_mapping_info
	{
	int 				sta_addr;
	PrgT_Mapping_Handle dup_mapping_hndl;
	}WlanT_Sta_Mapping_Info;

/* Information record for each STA */
typedef struct dup_mapping_info
	{
	int 								rem_sta_addr;
	WlanT_Mac_Duplicate_Buffer_Entry*	duplicate_ptr;
	}WlanT_Duplicate_Mapping_Info;

/* Information regarding the location of each APs */
typedef struct
	{
	int		ap_bss_id;
	int		ap_channel_num;
	double  tx_power;
	double	lat;
	double  lon;
	double  alt;
	}
WlanT_AP_Position_Info;


/** Global Variables **/

/* Global list of AP position info.											*/
List*	global_ap_pos_info_lptr = OPC_NIL;

/* Global variable to keep note of the nature of the subnet.				*/
/* This variable is initialized to not set.									*/
WlanT_Bss_Identification_Approach bss_id_type = WlanC_Not_Set;


/**	Macro Definitions **/

/** The data frame send flag is set whenever there is a data to be send by	**/
/** the higher layer or the response frame needs to be sent. However, in 	**/
/** either case the flag will not be set if the receiver is busy			**/