gps.h

根据GPS官方网站提供的gps定位方法而编写的C语言gps定位代码

#define CURRENT_CHANNEL_ASSIGNMENT_DATA_REQUEST 	( (unsigned char)  6 )
#define NAVIGATION_DATA_REQUEST_USER_COORDINATES 	( (unsigned char) ( 20  ) )
#define NAVIGATION_DATA_REQUEST_GPS_COORDINATES		( (unsigned char) ( 21  ) )
#define EPHEMERIS_REQUEST				( (unsigned char) ( 22  ) )
#define MEASUREMENT_BLOCK_DATA_REQUEST			( (unsigned char) ( 23  ) )
#define SATELLITE_VISIBILITY_DATA_AND_STATUS_REQUEST	( (unsigned char) ( 33  ) )
#define DGPS_CONFIGURATION_REQUEST			( (unsigned char) ( 43  ) )
#define SOFTWARE_IDENTIFICATION_INFORMATION_REQUEST	( (unsigned char) ( 45  ) )
#define DIFFERENTIAL_MESSAGE_STATUS_REQUEST		( (unsigned char) ( 48  ) )
#define INITIATE_LINK					( (unsigned char) 63 )
#define SET_OPERATING_MODE				( (unsigned char) 80 )
#define SET_GPS_CONFIGURATION				( (unsigned char) 83 )
#define SELECT_DEFINE_DATUM				( (unsigned char) 88 )
#define SET_DIFFERENTIAL_MESSAGE_CONFIGURATION		( (unsigned char) 91 )
#define ERASE_MEMORY					( (unsigned char) 99 )
#define CONFIGURE_MAIN_PORT_MODE			( (unsigned char) 110 )

#define TEN_HERTZ	3
#define FIVE_HERTZ	2
#define TWO_HERTZ	1
#define ONE_HERTZ	0

#define GET_CHANNEL_ASSIGNMENT	REQUEST0(CURRENT_CHANNEL_ASSIGNMENT_DATA_REQUEST)
#define GET_USER_NAVIGATION	REQUEST0(NAVIGATION_DATA_REQUEST_USER_COORDINATES)
#define GET_GPS_NAVIGATION	REQUEST0(NAVIGATION_DATA_REQUEST_GPS_COORDINATES )
#define GET_EPHEMERIS		REQUEST0(EPHEMERIS_REQUEST )
/*
#define GET_BLOCK_DATA		REQUEST1(MEASUREMENT_BLOCK_DATA_REQUEST,TEN_HERTZ)
*/
#define GET_BLOCK_DATA		REQUEST1(MEASUREMENT_BLOCK_DATA_REQUEST,ONE_HERTZ)
#define GET_VISIBILITY_DATA	REQUEST0(SATELLITE_VISIBILITY_DATA_AND_STATUS_REQUEST)
#define GET_GPS_CONFIGURATION	REQUEST0(DGPS_CONFIGURATION_REQUEST)
#define GET_SOFTWARE_IDENTIFICATION REQUEST0(SOFTWARE_IDENTIFICATION_INFORMATION_REQUEST)
#define GET_DIFFERENTIAL_MESSAGE_STATUS REQUEST0(DIFFERENTIAL_MESSAGE_STATUS_REQUEST)
#define SET_GPS_CONFIG		set_dgps_configuration(fd)
#define SET_DATUM		select_define_datum( fd, (unsigned char) datum )

#define CURRENT_CHANNEL_ASSIGNMENT_DATA_1_6		( (unsigned char)  6   )
#define CURRENT_CHANNEL_ASSIGNMENT_DATA_7_12		( (unsigned char)  7   )
#define NAVIGATION_DATA_USER_COORDINATES 		( (unsigned char)  20  )
#define NAVIGATION_DATA_GPS_COORDINATES			( (unsigned char)  21  )
#define EPHEMERIS_DATA					( (unsigned char)  22 )
#define MEASUREMENT_BLOCK_DATA				( (unsigned char)  23 )
#define SATELLITE_VISIBILITY_DATA_AND_STATUS		( (unsigned char)  33 )
#define DGPS_CONFIGURATION				( (unsigned char)  43 )
#define SOFTWARE_IDENTIFICATION_INFORMATION		( (unsigned char)  45 )
#define DIFFERENTIAL_MESSAGE_STATUS			( (unsigned char)  48 )
#define ACKNOWLEDGE_MESSAGE				( (unsigned char) 126 )

#define REQUEST0(R)	simple_request(fd, &mb, R)
#define REQUEST1(R,H)	simple_request1(fd, &mb, R, H)

typedef unsigned short CHECKSUM_TYPE;

typedef struct
{
	int  port;
	unsigned char header_buf[4];
	int  SOH;
	int  ID;		/* only seven bits */
	int  MSB_ID;
	int  Cmpl_ID;
	int  Msg_Data_Length;
	unsigned char Data[128];
	int CheckSum;
} MessageBlock;




typedef struct {
   unsigned char SOH;
   unsigned char Id;
   unsigned char NId;
   unsigned char Seq;
   } HEADER_TYPE;



typedef struct {
   unsigned char  SV;
   unsigned char  Bytes[72];
   } RAW_EPHEM_TYPE;

typedef struct {
   unsigned long Word3;
   unsigned long Word4;
   unsigned long Word5;
   unsigned long Word6;
   unsigned long Word7;
   unsigned long Word8;
   unsigned long Word9;
   unsigned long Word10;
   } SUBFRAME_ARRAY_TYPE;


typedef struct {
   double        X;
   double        Y;
   double        Z;
   } SV_XYZ_POS_TYPE;



typedef struct {
   unsigned char  Hours;	/* 1	1	*/
				/* bit 5 = 1 = True : Time not corrected by UTC parameters */
				/* bits 6-7         : reserved				   */

   unsigned char  Minutes;	/* 1	2	*/
   double         Seconds;	/* 8	10	*/
   unsigned char  Day;		/* 1	11	*/
				/* bits 5-7	    : reserved */

   unsigned char  Month;	/* 1	12	*/
   unsigned short Year;		/* 2	14	*/
   double         Latitude;	/* 8	22	*/
				/* -PI/2 -> PI/2 */

   double         Longitude;	/* 8	30	*/
				/* -PI -> PI */

   float          Altitude;	/* 4	34	*/
   float          Speed;	/* 4	38	*/ 
				/* Ground Speed in m/s */

   float          Angle;	/* 4	42	*/
				/* Track Angle  -PI -> PI */

   float          N_Vel;	/* 4	46	*/
				/* m/s 		*/

   float          E_Vel;	/* 4	50	*/
				/* m/s 		*/

   float          V_Vel;	/* 4	54	*/
				/* m/s 		*/

   float          HFOM;		/* 4	58	*/
   float          VFOM;		/* 4	62	*/
   unsigned short HDOP;		/* 2	64	resolution 0.1 units */
   unsigned short VDOP;		/* 2	66	resolution 0.1 units */
   unsigned char  Nav_Mode;	/* 1	67	*/
				/* bits 0-> 4 NAV mode
						0 - Init requited
						1 - Initialised
						2 - Nav 3-D
						3 - Alt. Hold (2-D)
						4 - Diff 3-D
						5 - Diff 3-D
						6 - Dead Reckoning
				   bit  5   solution confidence level
						0 - Normal ( <  5 SVs)
						1 - High   ( >= 5 SVs)
				   bit 6  	reserved
		
				   bit 7	GPS Time Alignent Mode
						1 - Enable
						0 - Disable
				*/
   unsigned char  Nb_SV;	/* 1	68	*/

				/* bits 0 -> 3	 - no of SVs for solution */
				/* bits 4 -> 7 coordinate system - lowest nibble */

   unsigned char  Sys_Mode;	/* 1	69	*/

				/* bits 4 -> 5  oordinate system - highest nibble */
				/* bit 7 : reserved */
				/* DATA = B69 b5, b4, B68 b7,b6,b5,b4 */ 

   unsigned char  Reserved1;	/* 1	70	*/
   unsigned char  Reserved2;	/* 1	71	*/
   } NAV_USER_TYPE;



typedef struct {
   double         GPS_Time_Sec;		/* 8 	0->7	*/
   unsigned short Week;			/* 2 	8->9	*/
   double         X_Pos;		/* 8 	10->17	*/
   double         Y_Pos;		/* 8 	18->25	*/
   double         Z_Pos;		/* 8 	26->33	*/
   float          X_Vel;		/* 4 	34->37	*/
   float          Y_Vel;		/* 4 	38->41	*/
   float          Z_Vel;		/* 4 	42->45	*/
   double         Clock_Bias;		/* 8 	46->53	*/
   double         Clock_Drift;		/* 8 	54	*/
   float          HFOM;			/* 4 	62	*/
   float          VFOM;			/* 4 	66	*/
   unsigned short HDOP;			/* 2 	70	*/
   unsigned short VDOP;			/* 2 	72	*/
   unsigned char  Nav_Mode;		/* 1 	74	*/
   unsigned char  Nb_SV;		/* 1 	75	*/
   unsigned char  Resv1;		/* 1 	76	*/
   unsigned char  Resv2;		/* 1 	77	*/
   unsigned char  Resv3;		/* 1 	78	*/
   CHECKSUM_TYPE Checksum;		/* 2 	79	*/
   } NAV_GPS_TYPE;

typedef struct {
   unsigned char SV;			/* 0 	1 */
   unsigned long Carrier_DCO;		/* 1 	4 */
   float         C_No;			/* 5 	4 */
   float         Reserved;		/* 9 	4 */
   unsigned char Status;		/* 13 	1 */
   } CHAN_ASSIGN_TYPE;

typedef struct {
   unsigned char    Set;		/* 0 	1 		*/
   CHAN_ASSIGN_TYPE Chan[6];   		/* 1 	84 = 6 * 14	*/
   CHECKSUM_TYPE    Checksum;		/* 85   2 		*/ 
   } CHANS_ASSIGN_TYPE;





typedef struct {
   unsigned char SV;			/* 0	1 */
   unsigned char SNR;			/* 1	1 */
   unsigned long Code_Phase;		/* 2	4 */
   unsigned long ICP;			/* 6	4 */
   unsigned char Locktime;		/* 10	1 */
   } FAST_MEAS_BLOCK_TYPE;	


typedef struct {
   int 			 port;
   signed char           Reserved1;	/* 0	1 */
   signed char           Reserved2;	/* 1	1 */
   unsigned char         Nb_Blocks;	/* 2	1 */
   double                GPS_Time;	/* 3	8 */
   FAST_MEAS_BLOCK_TYPE Block[12];	/* 11	(12 * 11) */
   CHECKSUM_TYPE         Checksum;	/* 143	2 */
   } FAST_MEAS_BLOCKS_TYPE;


typedef struct {
   unsigned char String[80];
   CHECKSUM_TYPE Checksum;
   } ERROR_LOG_TYPE;


typedef struct 
{
	unsigned char SV_Num;	/* 	0	1 */
	char Elevation;		/* 	1	1               -90 -> 90*/
	short int Azimuth;	/* 	2	2 		  0 -> 360
								bits 9->15 reserved */
	char SNR;		/* 	4	1 		 0 -> 90 */	
	
} Visibility_Datum;

typedef struct 
{
	unsigned char N_SV;	/* 	0	1	*/
	Visibility_Datum vd[12];	/*	1	12 * 5  - listed in decreasing elevation order */ 
} Visibility_Data;

typedef struct
{
		unsigned char status;			/*	0	1
								BIT 0 - ENABLE
								BIT 1-3 SHOULD BE 1
								bit 4-6 should be 0
								bit 7   port 0 = main, 1 =dedicated */

		unsigned char Differential_Coast_Time;	/*	1	1 */
		unsigned char Reserved;			/*	2	1 */
		unsigned char Baud_Rate;		/*	3	1 */
		unsigned char Msg_Req_ReTrans[8];	/*	4	8 */
		unsigned char Byte;			/*	12	1 */
		unsigned char Reserved8[8];		/*	13	8 */
		
} DGPS_Conf_Data;

typedef struct
{
	char operational_sw_part_number[14];		/* 0	14	*/
	char reserved_string[18];			/* 14	18	*/
	char boot_sw_part_number[14];			/* 32	14	*/
	char reserved40[40];				/* 46	40	*/
	int boot_checksum;				/* 86	4	*/
	int operational_checksum;			/* 90	4	*/
	char reserved;					/* 94	1	*/
} SW_Ident_Data;

typedef struct
{
	unsigned char station_id_lo;			/* 0  1 */
	unsigned char station_id_hi;			/* 1  1 */
	unsigned char message_no_received[8];		/* 2  8 */
	short int ValidWordCount;			/* 10 2 */
	short int ParityErrorCount;			/* 12 2 */
	char  Reserved6[6];				/* 14 6 */
	short int ZCount;				/* 20 2 */
	short int Reserved;				/* 22 2 */
	short int checksum;				/* 24 2 */
} Diff_Mesg_Data;

#define SELECT_DATUM				((unsigned char) 0 )
#define DEFINE_USER_DEFINED__DATUM		((unsigned char) 1 )
#define SELECT_AND_DEFINE_USER_DEFINED_DATUM	((unsigned char) 2 )
typedef struct
{
	unsigned char function;			/* 0  1 */
	unsigned char datum_number;		/* 1  1 */
	short int dx;				/* 2  2 */
	short int dy;				/* 4  2 */
	short int dz;				/* 6  2 */
	double a;				/* 8  8 */
						/* 8 bytes missing here */
	unsigned char Reserved[8];		/* 24 8 */

} Datum_Data;

/*--------------------------------------------------------------------------
Data use to compute satellite position and velocity
---------------------------------------------------------------------------*/
/* -- Factors of the series expansion of the true anomaly V.                */


typedef enum {
   NO_DATA=0,
   ALMANAC=1,
   EPHEMERID=2
   } SV_DATA_SOURCE_TYPE;

typedef struct {
   double                Root_A;
   double		 del_N;	/* extended by David to carry raw ephemeris */
   double                N;
   double                C0;
   double		 W;	/* extended by David to carry raw ephemeris */
   double                Sin_W; 
   double                Cos_W; 
   double                I_Dot;
   double                Omega_Dot;
   double                Crc;
   double                I_0;
   double                Cis;
   double                Omega_0;
   double                Cic;
   double                Toe;
   double                Cus;
   double                E;
   double                Cuc;
   double                M0;
   double                Crs;
   unsigned char         Curve_Interval;
   SV_DATA_SOURCE_TYPE   SV_Data_Source;
   unsigned long         IODE;
   unsigned char         Valid_Ephem_Decoded;
   } ORBIT_PARAMETERS_TYPE;

typedef struct {
   double Af0;
   double Af1;
   double Af2;
   double Toc;
   double Tgd;
   } CLOCK_PARAMETERS_TYPE;




extern int got_block_data[40];
extern int got_ephemeris_data[40];

extern char * nav_mode_names[32];
extern char * system_mode_names[16];
extern char * tracking_state_name[4];
extern char * allocation_state_name[4];
extern char * carrier_phase_staus_name[4];
extern char * sv_status_name[4];
extern char *  dgps_status_name[8];
extern int messages_back[];
extern unsigned char Ephem_Avaliable[];
















void Get_Visibility(MessageBlock * mb);
void Get_GPS_Configuration(MessageBlock * mb);
void select_define_datum(int fd, unsigned char datum);
void configure_main_port(int fd,int datum);
void set_operating_mode(int fd, int datum, double hours);

/*
	51 degrees 52' 22.1" N          0 degrees 57' 10.0" E
*/ 
#define MY_LAT	( 51.0 + (52.0 / 60.0) + (22.1/3600.0) )
#define MY_LON  (  0.0 + (57.0 / 60.0) + (10.0/3600.0) )
#define MY_ALT  40.0

#define REFERENCE_PORT	0
#define MOBILE_PORT	1