db.samplecol.find().sort({"properties.aar":1})

{ "_id" : ObjectId("5ad70f71f2119236741ffb03"), "geometry" : { "type" : "Point", "coordinates" : [ 119.6164, 4.7121 ] }, "type" : "Feature", "properties" : { "STATUS" : "0", "TIMESTAMP" : "2013-12-31 18:49:00.000", "aar" : "205580000", "COURSE" : "175", "SPEED" : "153", "HEADING" : "176" } }