jgg     2008 28 (5):  68-72    ISSN: 0412-1961  CN: 21-1139/TG METHOD OF RATIO ACCUMULATION OF GNSS AND FAST DOUBLE-DIFFERENCED AMBIGUITY RESOLUTION Tang Weiming 1) ; Sun Hongxing 2) ; and Chen Jiang 3) 1)GNSS Research Center，Wuhan University，Wuhan 4300792)The School of Remote Sensing Information Engineering, Wuhan University, Wuhan 4300793)Uint No. 22 , 92493, Liaoning 125000 Received: 1900-01-01  Revised: 1900-01-01  Online: null Supporting info null