提出了一套适用于GNSS精密单点定位(PPP)的实时质量控制方法,重点研究了钟跳探测与修复、周跳探测与标记、抗差估计方法,并在现有质量控制方法的基础上进行了改进。对比分析了不同质量控制方案对PPP的影响,结果表明,钟跳不利于周跳探测,严重影响非差PPP的精度和效率,必须对其进行探测与修复;联合MW、GF组合可以探测出绝大多数周跳,且较使用单一方法更为准确、可靠;采用改进的抗差估计有效抑制了残余粗差对精密定位的影响,显著提高了PPP的精度和可靠性。
We discuss a real-time quality control (QC) procedure for precise point positioning (PPP) with emphasis given to the detection and repair of clock jump, cycle slip detection and robust estimation. Four schemes with different QC procedures are designed to test the effects on PPP. The results show that clock jump should be first compensated during the preprocessing phase since it may cause the cycle slip detection invalid and seriously affect the precision and efficiency of zero-difference PPP. The union of MW and GF combinations can detect the vast maiority of cycle slips which is more accurate and reliable than any single one. With an improved robust estimation, gross errors and their impact on positioning are effec- tively suppressed, which led to significant improvements in the accuracy and reliability of PPP.