【RTKLIB 2.4.3 b34 】版本更新简介一

了解一个开源库更新内容的最直接的文件就是readme.txt，更新内容为：

• NavIC (IRNSS) completely supported.
• RINEX 3.04 supported. BDS-3 and QZSS new signals added.
• RTCM 3.3 amendment-1 supported. MT1041/1131-7 (NavIC ephemeris/MSM)
  added.
• RTCM3 MT1230 (GLONASS code-phase biases) supported.
• RTCM3 MT4076 (IGS SSR) supported.
• GNSS singal ID changed: L1,L2,L5/3,L6,L7,L8,L9 -> L1,L2,L3,L4,L5.
• Only Windows 64bit APs supported. 32bit APs deleted.
• Windows scaled DPI APs supported for different DPI screens.
• Directories RTKLIB/app and RTKLIB/data reorganized.
• License clarified. See RTKLIB/LICENSE.txt.
• Bugs and problems fixed including GitHub Issues:
  #461,#477,#480,#514,#540,#547,#555,#560.

从以上11点更新来看，主要是对rinex3.04和rtcm3的支持。

我对第11点的问题感兴趣，bugs分别是：
#461: ZED f9p strsvr ubx-> rtcm3 conversion
#477: ntrip browser map view not working
#480: Post releases on Releases tab instead of in RTKLIB_bin repo
#514: stec.c missing
#540: License in separate file
#547: Missing header <sys/select.h> in rtklib.h
#555: exec convbin find a problem
#560: Issue with Delta Clock C2 value

具体issue可以查看对应的序列号找到详细的问题描述。从以上8个bugs来看，好像没有大的更新值得关注。
再往下看readme.txt，会发现api有变化（新添/优化/删除），分别是：

• The following APIs added:

     code2freq(),sat2freq(),code2idx(),timereset(),setseleph(),getseleph(),
     decode_gal_fnav(),decode_irn_nav()
  

• The following APIs modified:

     obs2code(),code2obs(),setcodepri(),getcodepri(),tickget(),traceb(),
     getbitu(),getbits(),setbitu(),getbits(),rtk_crc32(),rtk_crc24q(),
     rtk_crc16(),docode_word(),decode_frame(),test_glostr(),decode_glostr(),
     decode_bds_d1(),decode_bds_d2(),decode_gal_inav(),input_raw(),input_oem4(),
     input_oem3(),input_ubx(),input_ss2(),input_cres(),input_stq(),gen_ubx(),
     gen_stq(),gen_nvs(),input_rtcm2(),input_rtcm3(),gen_rtcm3(),inputsol(),
     outprcopts(),outsolheads(),outsols(),outsolexs(),outnmea_rmc(),
     out_nmea_gga(),outnmea_gsa(),outnmea_gsv(),sbsdecodemsg(),strread(),
     strwrite(),strsvrstart(),strsvrstat(),showmsg()
  

• The following APIs deleted:

     lam_carr[],satwavelen(),csmooth(),satseleph(),input_gw10(),input_cmr(),
     input_tersus(),input_lexr(),input_gw10f(),input_cmrf(),input_tersusf(),
     input_lexrf(),gen_lexr(),strgetsel(),strsetsel(),strsetsrctbl(),
     pppcorr_read(),pppcorr_free(),pppcorr_trop().pppcorr_stec(),
     stsvrsetsrctbl(),init_imu(),input_imu(),lexupdatecorr(),lexreadmsg(),
     lexoutmsg(),lexconvbin(),lexeph2pos(),lexioncorr()
  

• The following types modified:

     obsd_t,eph_t,nav_t,rtcm_t,rnxctr_t,prcopt_t,rnxopt_t,ssat_t,raw_t,strsvr_t
  

• The following types deleted:

     lexmsg_t,lex_t,lexeph_t,lexion_t,stec_t,trop_t,pppcorr_t,exterr_t,
     half_cyc_t,imud_t,imu_t
  

接下来就是对接收机的支持，这部分代码主要在src/rcv中。
再往下的内容就是对各种APs的更新，我们学习开源库最重要的两个AP就是rtkpost和rtknavi了，重点关注这两个程序的更新内容，具体如下：

• RTKPOST:

   TGD and BGD handling improved for Galileo and BDS.
   Always L1-L2 (E1-E5b for Galileo, B1-B2 for BDS) used for Iono-Free LC. 
   Always I/NAV used for Galileo orbits and clocks.
   SP3-d format for precise ephemerides supported.
   CPU usage much improved in SD to DD conversion for ambiguity resolution.
   OpenBLAS linked instead of Intel MKL for fast-matrix computation.
   Option QZSS LEX and Input STEC for ionos-correction no longer supported.
   Option Input ZTD for troposphere correction no longer supported.
   AP RTKPOST_WIN64 and RTKPOST_MKL deleted.
  

• RTKNAVI:

   NMEA talker ID GQ and GI (NMEA 0183 4.11) for QZSS and NavIC supported.
   NMEA GQ/GB/GI-GSA/GSV sentences supported.
   Option Panel Font added.
   Menus reorganized in RTK Monitor.
   Menu Station Info added to RTK Monitor.
   Satellite positions in Skyplot by TLE data no longer supported.
   Menu LEX and Iono Correction deleted from RTK Monitor.
   AP RTKNAVI_WIN64 deleted.
  

在rtkpost中，最亮点的内容就是模糊度计算中单差向双差转换的CPU使用效率提升，在快速矩阵计算的时候使用OpenBLAS替换MKL，其中：OpenBLAS is an optimized Basic Linear Algebra Subprograms (BLAS) library based on GotoBLAS2 1.13 BSD version.（最优线性代数子程序），Intel MKL：Intel Math Kernel Library，英特尔数学核心函数库。这就解释了文章《rtklib新版本2.4.3 b34测试对比》和《RTKlib 2.4.3 b34数据测试与性能分析》运行效率提升的原因。

总结：由readme.txt总体上知道了更新了是哪些内容，也知道看代码的重点在哪里，接下来我会从src入手源码看看更新前后的diff和新add的api。预计本周会对src中除rcv的更新做个详细总结，希望大家一起交流。