jgg     2015 35 (4):  666-670    ISSN: 0412-1961  CN: 21-1139/TG Improving the Performance of MW Combined Observation on Cycle Slip Detection Using EMD Threshold De-Noising 1 School of Geography Spatial Information, Information Engineering University, 62 Kexue Road, Zhengzhou 450001,China 2 Troop 93787，Beijing 100076,China Received: 2014-06-23  Revised: null  Online: 2015-07-29 Supporting info