“…1,2 However, there are some disadvantages associated with TRN, such as large errors in terrain measurement, fewer terrain features, and the lower acquisition speed of the measurement data, which always cause large position deviation. 1 At present, the research on improving the TRN/terrain reference position (TRP) accuracy mainly focuses on the filtering algorithm, including particle filter (PF), 1,3 –6 robust filtering algorithm, 7,8 –10 point mass filter (PMF), 5,11,12 and so on. The latest research progress on TRN can be referred to the review article.…”