Rinex观测文件&导航文件，头文件，RTKLIB解析

一、Rinex 观测文件，头部分

如下为观测文件头文件：GPS头、rinex 3.02版本

     3.02           OBSERVATION DATA    G (GPS)             RINEX VERSION / TYPE
BLANK OR G = GPS, R = GLONASS, C = BDS, E = GAL, M = MIXED  COMMENT             
HGO                 ex/_?              20200628 091105 UTC PGM / RUN BY / DATE 
394                                                         MARKER NAME         
                                                            MARKER NUMBER       
whoever             ex/_?                                  OBSERVER / AGENCY   
10015394            iRTK2                                   REC # / TYPE / VERS 
1                   G3-IRTK2                                ANT # / TYPE        
 -2365886.5935  4347316.6784  4009459.3017                  APPROX POSITION XYZ 
------------------------------------------------------------COMMENT             
*** Antenna height is from mark to ANTENNA Phase Center.    COMMENT             
------------------------------------------------------------COMMENT             
        0.0896        0.0000        0.0000                  ANTENNA: DELTA H/E/N
G    6 C1C C2W C2X L1C L2W L2X                              SYS / # / OBS TYPES 
     1.000                                                  INTERVAL            
  2019    11    23     8    53   26.0000000     GPS         TIME OF FIRST OBS   
     0                                                      RCV CLOCK OFFS APPL 
    18                                                      LEAP SECONDS        
                                                            END OF HEADER  

RTKLIB中，首先读取的是移动站的观测文件，其中RCV=1，

头文件的信息全部记录在结构体 sta_t sta中：

typedef struct {        /* station parameter type */
    char name   [MAXANT]; /* marker name */
    char marker [MAXANT]; /* marker number */
    char antdes [MAXANT]; /* antenna descriptor */
    char antsno [MAXANT]; /* antenna serial number */
    char rectype[MAXANT]; /* receiver type descriptor */
    char recver [MAXANT]; /* receiver firmware version */
    char recsno [MAXANT]; /* receiver serial number */
    int antsetup;       /* antenna setup id */
    int itrf;           /* ITRF realization year */
    int deltype;        /* antenna delta type (0:enu,1:xyz) */
    double pos[3];      /* station position (ecef) (m) */
    double del[3];      /* antenna position delta (e/n/u or x/y/z) (m) */
    double hgt;         /* antenna height (m) */
} sta_t;

在实际中，常用的参数为：

1、判断头文件中 第一行导航系统类型：RINEX VERSION / TYPE

目的设置：处理时的导航系统，时间系统：

        else if (strstr(label,"RINEX VERSION / TYPE")) {
            *ver=str2num(buff,0,9);
            *type=*(buff+20);
            
            /* satellite system */
            switch (*(buff+40)) {
                case ' ':
                case 'G': *sys=SYS_GPS;  *tsys=TSYS_GPS; break; /* 观测文件头，为G，则导航系统和时间系统为GPS、TSYS_GPS */
                case 'R': *sys=SYS_GLO;  *tsys=TSYS_UTC; break;
                case 'E': *sys=SYS_GAL;  *tsys=TSYS_GAL; break; /* v.2.12 */
                case 'S': *sys=SYS_SBS;  *tsys=TSYS_GPS; break;
                case 'J': *sys=SYS_QZS;  *tsys=TSYS_QZS; break; /* v.3.02 */
                case 'C': *sys=SYS_CMP;  *tsys=TSYS_CMP; break; /* v.2.12 */
                case 'I': *sys=SYS_IRN;  *tsys=TSYS_IRN; break; /* v.3.03 */
                case 'M': *sys=SYS_NONE; *tsys=TSYS_GPS; break; /* mixed */
                default :
                    trace(2,"not supported satellite system: %c\n",*(buff+40));
                    break;
            }
            continue;
        }

 2、sta信息

 对应信息如下;

MARKER NAME sta->name

MARKER NUMBER sta->marker

REC # / TYPE / VERS  sta->recsno  sta->rectype   sta->recver 接收机序列号、接收机类型描述、接收机固件版本

举例：   5023K67990          TRIMBLE NETR9       5.22,20/MAR/2017    REC # / TYPE / VERS

ANT # / TYPE  sta->antsno  sta->antdes 天线序列号、天线类型

举例： 4928353386          TRM59800.00     SCIS                    ANT # / TYPE

if      (strstr(label,"MARKER NAME"         )) {
        if (sta) setstr(sta->name,buff,60);
    }
    else if (strstr(label,"MARKER NUMBER"       )) { /* opt */
        if (sta) setstr(sta->marker,buff,20);
    }
    else if (strstr(label,"MARKER TYPE"         )) ; /* ver.3 */
    else if (strstr(label,"OBSERVER / AGENCY"   )) ;
    else if (strstr(label,"REC # / TYPE / VERS" )) {
        if (sta) {
            setstr(sta->recsno, buff,   20);
            setstr(sta->rectype,buff+20,20);
            setstr(sta->recver, buff+40,20);
        }
    }
    else if (strstr(label,"ANT # / TYPE"        )) {
        if (sta) {
            setstr(sta->antsno,buff   ,20);
            setstr(sta->antdes,buff+20,20);
        }
    }
    else if (strstr(label,"APPROX POSITION XYZ" )) {
        if (sta) {
            for (i=0,j=0;i<3;i++,j+=14) sta->pos[i]=str2num(buff,j,14);
        }
    }
    else if (strstr(label,"ANTENNA: DELTA H/E/N")) {
        if (sta) {
            for (i=0,j=0;i<3;i++,j+=14) del[i]=str2num(buff,j,14);
            sta->del[2]=del[0]; /* h */
            sta->del[0]=del[1]; /* e */
            sta->del[1]=del[2]; /* n */
        }
    }

3、站的大致坐标：APPROX POSITION XYZ

    else if (strstr(label,"APPROX POSITION XYZ" )) {
        if (sta) {
            for (i=0,j=0;i<3;i++,j+=14) sta->pos[i]=str2num(buff,j,14);
        }
    }

4、天线的 ANTENNA: DELTA H/E/N

    else if (strstr(label,"ANTENNA: DELTA H/E/N")) {
        if (sta) {
            for (i=0,j=0;i<3;i++,j+=14) del[i]=str2num(buff,j,14);
            sta->del[2]=del[0]; /* h */
            sta->del[0]=del[1]; /* e */
            sta->del[1]=del[2]; /* n */
        }
    }

5、数据观测类型 ： SYS / # / OBS TYPES

i 表示 卫星系统类型在syscodes字符串中的元素序号： syscodes[]="GREJSCI";

n 为观测文件头文件中 数据观测类型的个数

tobs[i][nt]第一个[]中代表卫星系统

else if (strstr(label,"SYS / # / OBS TYPES" )) { /* ver.3 */
        if (!(p=strchr(syscodes,buff[0]))) {
            trace(2,"invalid system code: sys=%c\n",buff[0]);
            return;
        }
        i=(int)(p-syscodes); //表示 卫星系统类型 syscodes[]="GREJSCI";
        n=(int)str2num(buff,3,3);//n 为观测文件头文件中 obs types 的个数
        for (j=nt=0,k=7;j58) {
                if (!fgets(buff,MAXRNXLEN,fp)) break;
                k=7;
            }
            if (nt 3.02/3.03 */
        if (i==5) {
            for (j=0;j

6、跳秒信息放到 nav_t 结构体中

    else if (strstr(label,"LEAP SECONDS"        )) { /* opt */
        if (nav) nav->leaps=(int)str2num(buff,0,6);
    }

7、在读取观测文件数据记录部分；

读取数据记录部分时，先将文件头的数据观测类型进行处理

/* type definition -----------------------------------------------------------*/
typedef struct {                        /* signal index type */
    int n;                              /* number of index */
    int frq[MAXOBSTYPE];                /* signal frequency (1:L1,2:L2,...) */
    int pos[MAXOBSTYPE];                /* signal index in obs data (-1:no) */
    unsigned char pri [MAXOBSTYPE];     /* signal priority (15-0) */
    unsigned char type[MAXOBSTYPE];     /* type (0:C,1:L,2:D,3:S) */
    unsigned char code[MAXOBSTYPE];     /* obs code (CODE_L??) */
    double shift[MAXOBSTYPE];           /* phase shift (cycle) */
} sigind_t;

针对某一个卫星导航系统下，n为当前历元数据类型个数；

pri为信号优先级，以数字的形式，表示某一个频率下，观测类型的优先级；

type为数据观测类型，其值为obscodes[]="CLDS"；中的顺序。

code为数据类型的频率，其值为 *obscodes[] 中的值；

frq为数据频率；

调用子函数：

set_index(ver,SYS_GPS,opt,tobs[0],index  );

 1、观测数据类型频率

ind->code[i]=obs2code(tobs[i]+1,ind->frq+i);

首先根据*obscodes[]与数据观测类型进行依次比较：通过strcmp函数，

• 如果两者一致/相等，则将此数据类型通过 obsfreqs查找对应的频率，并赋值到 ind->frq
• 如果两者不一致，则continue，继续执行下一次循环，……；

返回值，赋值给ind->code  其值为 *obscodes[] 中的值；

2、观测数据类型

ind->type[i]=(p=strchr(obscodes,tobs[i][0]))?(int)(p-obscodes):0;

obscodes[]="CLDS"；

举例：数据观测类型：G    6 C1C C2W C2X L1C L2W L2X                              SYS / # / OBS TYPES

则，tobs[i][0]=C //第一个数据类型C1C的第一个字符

因此，p=strchr(obscodes,tobs[i][0]) 为CLDS

最终将，数据观测类型赋值给 ind->type，其值为obscodes[]="CLDS"；中的顺序。

3、观测数据类型 信号优先级

ind->pri[i]=getcodepri(sys,ind->code[i],opt);

ind->pri 返回的是某频率下，观测类型的优先级，其中14/e表示最高优先级！

以：G    6 C1C C2W C2X L1C L2W L2X                              SYS / # / OBS TYPES

第一个数据类型为：C1C ；其相应的值如下：

C2X：

L1C

L2W

L2X

 

 

static char *obscodes[]={       /* observation code strings */
    
    ""  ,"1C","1P","1W","1Y", "1M","1N","1S","1L","1E", /*  0- 9 */
    "1A","1B","1X","1Z","2C", "2D","2S","2L","2X","2P", /* 10-19 */
    "2W","2Y","2M","2N","5I", "5Q","5X","7I","7Q","7X", /* 20-29 */
    "6A","6B","6C","6X","6Z", "6S","6L","8L","8Q","8X", /* 30-39 */
    "2I","2Q","6I","6Q","3I", "3Q","3X","1I","1Q","5A", /* 40-49 */
    "5B","5C","9A","9B","9C", "9X",""  ,""  ,""  ,""    /* 50-59 */
};
static unsigned char obsfreqs[]={
    /* 1:L1/E1, 2:L2/B1, 3:L5/E5a/L3, 4:L6/LEX/B3, 5:E5b/B2, 6:E5(a+b), 7:S */
    0, 1, 1, 1, 1,  1, 1, 1, 1, 1, /*  0- 9 */
    1, 1, 1, 1, 2,  2, 2, 2, 2, 2, /* 10-19 */
    2, 2, 2, 2, 3,  3, 3, 5, 5, 5, /* 20-29 */
    4, 4, 4, 4, 4,  4, 4, 6, 6, 6, /* 30-39 */
    2, 2, 4, 4, 3,  3, 3, 1, 1, 3, /* 40-49 */
    3, 3, 7, 7, 7,  7, 0, 0, 0, 0  /* 50-59 */
};
static const char obscodes[]="CLDS";    /* obs type codes */

static const char frqcodes[]="1256789"; /* frequency codes */

#define CODE_NONE   0                   /* obs code: none or unknown */
#define CODE_L1C    1                   /* obs code: L1C/A,G1C/A,E1C (GPS,GLO,GAL,QZS,SBS) */
#define CODE_L1P    2                   /* obs code: L1P,G1P    (GPS,GLO) */
#define CODE_L1W    3                   /* obs code: L1 Z-track (GPS) */
#define CODE_L1Y    4                   /* obs code: L1Y        (GPS) */
#define CODE_L1M    5                   /* obs code: L1M        (GPS) */
#define CODE_L1N    6                   /* obs code: L1codeless (GPS) */
#define CODE_L1S    7                   /* obs code: L1C(D)     (GPS,QZS) */
#define CODE_L1L    8                   /* obs code: L1C(P)     (GPS,QZS) */
#define CODE_L1E    9                   /* (not used) */
#define CODE_L1A    10                  /* obs code: E1A        (GAL) */
#define CODE_L1B    11                  /* obs code: E1B        (GAL) */
#define CODE_L1X    12                  /* obs code: E1B+C,L1C(D+P) (GAL,QZS) */
#define CODE_L1Z    13                  /* obs code: E1A+B+C,L1SAIF (GAL,QZS) */
#define CODE_L2C    14                  /* obs code: L2C/A,G1C/A (GPS,GLO) */
#define CODE_L2D    15                  /* obs code: L2 L1C/A-(P2-P1) (GPS) */
#define CODE_L2S    16                  /* obs code: L2C(M)     (GPS,QZS) */
#define CODE_L2L    17                  /* obs code: L2C(L)     (GPS,QZS) */
#define CODE_L2X    18                  /* obs code: L2C(M+L),B1I+Q (GPS,QZS,CMP) */
#define CODE_L2P    19                  /* obs code: L2P,G2P    (GPS,GLO) */
#define CODE_L2W    20                  /* obs code: L2 Z-track (GPS) */
#define CODE_L2Y    21                  /* obs code: L2Y        (GPS) */
#define CODE_L2M    22                  /* obs code: L2M        (GPS) */
#define CODE_L2N    23                  /* obs code: L2codeless (GPS) */
#define CODE_L5I    24                  /* obs code: L5/E5aI    (GPS,GAL,QZS,SBS) */
#define CODE_L5Q    25                  /* obs code: L5/E5aQ    (GPS,GAL,QZS,SBS) */
#define CODE_L5X    26                  /* obs code: L5/E5aI+Q/L5B+C (GPS,GAL,QZS,IRN,SBS) */
#define CODE_L7I    27                  /* obs code: E5bI,B2I   (GAL,CMP) */
#define CODE_L7Q    28                  /* obs code: E5bQ,B2Q   (GAL,CMP) */
#define CODE_L7X    29                  /* obs code: E5bI+Q,B2I+Q (GAL,CMP) */
#define CODE_L6A    30                  /* obs code: E6A        (GAL) */
#define CODE_L6B    31                  /* obs code: E6B        (GAL) */
#define CODE_L6C    32                  /* obs code: E6C        (GAL) */
#define CODE_L6X    33                  /* obs code: E6B+C,LEXS+L,B3I+Q (GAL,QZS,CMP) */
#define CODE_L6Z    34                  /* obs code: E6A+B+C    (GAL) */
#define CODE_L6S    35                  /* obs code: LEXS       (QZS) */
#define CODE_L6L    36                  /* obs code: LEXL       (QZS) */
#define CODE_L8I    37                  /* obs code: E5(a+b)I   (GAL) */
#define CODE_L8Q    38                  /* obs code: E5(a+b)Q   (GAL) */
#define CODE_L8X    39                  /* obs code: E5(a+b)I+Q (GAL) */
#define CODE_L2I    40                  /* obs code: B1I        (BDS) */
#define CODE_L2Q    41                  /* obs code: B1Q        (BDS) */
#define CODE_L6I    42                  /* obs code: B3I        (BDS) */
#define CODE_L6Q    43                  /* obs code: B3Q        (BDS) */
#define CODE_L3I    44                  /* obs code: G3I        (GLO) */
#define CODE_L3Q    45                  /* obs code: G3Q        (GLO) */
#define CODE_L3X    46                  /* obs code: G3I+Q      (GLO) */
#define CODE_L1I    47                  /* obs code: B1I        (BDS) */
#define CODE_L1Q    48                  /* obs code: B1Q        (BDS) */
#define CODE_L5A    49                  /* obs code: L5A SPS    (IRN) */
#define CODE_L5B    50                  /* obs code: L5B RS(D)  (IRN) */
#define CODE_L5C    51                  /* obs code: L5C RS(P)  (IRN) */
#define CODE_L9A    52                  /* obs code: SA SPS     (IRN) */
#define CODE_L9B    53                  /* obs code: SB RS(D)   (IRN) */
#define CODE_L9C    54                  /* obs code: SC RS(P)   (IRN) */
#define CODE_L9X    55                  /* obs code: SB+C       (IRN) */
#define MAXCODE     55                  /* max number of obs code */

static char codepris[7][MAXFREQ][16]={  /* code priority table */
   
   /* L1/E1      L2/B1        L5/E5a/L3 E6/LEX/B3 E5b/B2    E5(a+b)  S */
    {"CPYWMNSL","PYWCMNDSLX","IQX"     ,""       ,""       ,""      ,""    }, /* GPS */
    {"PC"      ,"PC"        ,"IQX"     ,""       ,""       ,""      ,""    }, /* GLO */
    {"CABXZ"   ,""          ,"IQX"     ,"ABCXZ"  ,"IQX"    ,"IQX"   ,""    }, /* GAL */
    {"CSLXZ"   ,"SLX"       ,"IQX"     ,"SLX"    ,""       ,""      ,""    }, /* QZS */
    {"C"       ,""          ,"IQX"     ,""       ,""       ,""      ,""    }, /* SBS */
    {"IQX"     ,"IQX"       ,"IQX"     ,"IQX"    ,"IQX"    ,""      ,""    }, /* BDS */
    {""        ,""          ,"ABCX"    ,""       ,""       ,""      ,"ABCX"}  /* IRN */
};

二、Rinex 导航文件，头部分

如下为导航文件头文件：GPS头、rinex 3.02版本

     3.02           N: GNSS NAV DATA    G: GPS              RINEX VERSION / TYPE
HGO                 ex/_?              20200628 091105 UTC PGM / RUN BY / DATE 
GPSA   1.1176D-08 -1.4901D-08 -5.9605D-08  1.1921D-07       IONOSPHERIC CORR    
GPSB   9.8304D+04 -1.1469D+05 -1.9661D+05  7.2090D+05       IONOSPHERIC CORR    
    18                                                      LEAP SECONDS        
                                                            END OF HEADER   

1、读取电离层参数

Rinex 3版本

    else if (strstr(label,"IONOSPHERIC CORR"    )) { /* opt ver.3 */
        if (nav) {
            if (!strncmp(buff,"GPSA",4)) {
                for (i=0,j=5;i<4;i++,j+=12) nav->ion_gps[i]=str2num(buff,j,12);
            }
            else if (!strncmp(buff,"GPSB",4)) {
                for (i=0,j=5;i<4;i++,j+=12) nav->ion_gps[i+4]=str2num(buff,j,12);
            }
            else if (!strncmp(buff,"GAL",3)) {
                for (i=0,j=5;i<4;i++,j+=12) nav->ion_gal[i]=str2num(buff,j,12);
            }
            else if (!strncmp(buff,"QZSA",4)) { /* v.3.02 */
                for (i=0,j=5;i<4;i++,j+=12) nav->ion_qzs[i]=str2num(buff,j,12);
            }
            else if (!strncmp(buff,"QZSB",4)) { /* v.3.02 */
                for (i=0,j=5;i<4;i++,j+=12) nav->ion_qzs[i+4]=str2num(buff,j,12);
            }
            else if (!strncmp(buff,"BDSA",4)) { /* v.3.02 */
                for (i=0,j=5;i<4;i++,j+=12) nav->ion_cmp[i]=str2num(buff,j,12);
            }
            else if (!strncmp(buff,"BDSB",4)) { /* v.3.02 */
                for (i=0,j=5;i<4;i++,j+=12) nav->ion_cmp[i+4]=str2num(buff,j,12);
            }
            else if (!strncmp(buff,"IRNA",4)) { /* v.3.03 */
                for (i=0,j=5;i<4;i++,j+=12) nav->ion_irn[i]=str2num(buff,j,12);
            }
            else if (!strncmp(buff,"IRNB",4)) { /* v.3.03 */
                for (i=0,j=5;i<4;i++,j+=12) nav->ion_irn[i+4]=str2num(buff,j,12);
            }
        }
    }

Rinex 2版本

    if      (strstr(label,"ION ALPHA"           )) { /* opt ver.2 */
        if (nav) {
            for (i=0,j=2;i<4;i++,j+=12) nav->ion_gps[i]=str2num(buff,j,12);
        }
    }
    else if (strstr(label,"ION BETA"            )) { /* opt ver.2 */
        if (nav) {
            for (i=0,j=2;i<4;i++,j+=12) nav->ion_gps[i+4]=str2num(buff,j,12);
        }
    }

2、跳秒信息

    else if (strstr(label,"LEAP SECONDS"        )) { /* opt */
        if (nav) nav->leaps=(int)str2num(buff,0,6);
    }