大侠们分析一下，协议里面NDSSIGN签名的算法
这是从我的模块读出的信息
主机发的指令：AT+POSI=1,"EF823023E12109CB5642D9CF416A83CB"

GSM模块应答的指令：
+POSI: 1,460,00,865E,4DCA,0E,47,0,460,00,865E,5ECF,08,42,0,460,00,865E,4DCB,11,41,0,460,00,865E,6A88,1D,38,0,460,00,865E,6A8B,22,33,1,"EF823023E12109CB5642D9CF416A83CB","01001503800700104b80d0d3ec8f35339fdb009e6d6c9f43"
OK

签名："01001503800700104b80d0d3ec8f35339fdb009e6d6c9f43"是怎么算出来的，