Fixed and mobile global navigation satellite system (GNSS) reference stations are the main differential positioning resources for automated steering system in China at current stage.However,with the rapid increase in GNSS reference stations usage,there is an increasing trend of serious radio frequency interference,which mainly due to deficiency of technical and management coordination.To solve this problem,a cloud based architecture that achieved regional GNSS reference stations management and information sharing for agricultural applications was proposed.Shihezi,a district of Xinjiang,was selected as the study area.The accurate information (i.e.,name,position,and frequency) of 84 fixed reference stations from three enterprises was collected,based on which the difference of distance (△D) and the difference of frequency (△F) between each two reference stations were calculated.By using △D and △F,redundancy and frequency interference were analyzed,coordinate adjustment of two stations were conducted,and the prototype system and an APP were developed for reference station management and agricultural applications.The results showed that the 84 reference stations occupied 26.7 MHz frequency band with 47 frequencies,and 30 of which were independent frequency.In addition,there were 18 couples of stations using the same frequencies and 29 pairs of stations using near frequencies (△F≤25 kHz) within 40 km in northeast of Shihezi.The average redundancy was 263.2％,and the redundancy of central area was even worse.To benefit from the redundancy information,it was utilized to adjust the coordinate of the GNSS reference station in order to improve the reliability of differential signal access.Three stations were tested and the precision to millimeter level and centimeter level for longitude and latitude respectively,which meant the coordinate adjustment can improve the accuracy of GNSS reference stations.The prototype system and APP achieved the functions such as stations recording,interference detection,station construction assistance,and frequency recommendation,and it can improve the management efficiency of GNSS reference stations and reduce radio frequency interference.%针对区域农用卫星导航定位基准站规模化应用中存在无效冗余、频率干扰和基准不统一问题,提出基于云端管理构架实现区域基准站管理与信息共享的初步解决方案.选择石河子市作为研究区,获得3个企业总计84个固定基准站的备案数据,计算任意2个基准站的站间距△D和频率差△F形成数据集E.在此基础上,利用GIS空间分析和数值统计方法,分析基准站无效冗余和同近频干扰,开展基准站坐标平差与精度验证,开发基准站管理服务系统原型.研究表明,由于缺乏技术和管理协调,区域农用GNSS基准站无效冗余、频率干扰和频率浪费难以避免,所统计的84个基准站占用了26.7 MHz频带,使用了47个频点,其中30个基准站使用单独频点,站间距40 km以内时多达18对基准站频率相同,29对基准站频率相近(AF≤25 kHz).石河子东北18个基准站,平均冗余率达263.2％,中心区冗余率更高.固定基准站通过坐标平差可以提高站址精度,有利于发挥基准站冗余的有效性和提高差分信号接入的可靠性,3个验证点的经度坐标差最大为0.011 m,纬度坐标差最大为0.023 m,精度分别达到毫米级和厘米级.管理服务系统原型和手机端APP原型的初步测试表明,系统可以实现基准站备案、建站辅助、基准站查询和频率推荐等功能,可以提高基准站管理效率和减少干扰现象.
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