jgg     2015 35 (6):  1031-1035    ISSN: 0412-1961  CN: 21-1139/TG Fixed-Interval Smoothing Post-Processing Algorithms Based on  Tightly Coupled Carrier Phase DGNSS/INS Method 1 College of Navigation and Aerospace Engineering, Information Engineering University, 62 Kexue Road, Zhengzhou 450052,China 2 71687 Troops, Xinxiang 453000,China Received: 2014-10-17  Revised: null  Online: 2015-12-01 Supporting info