为避免混叠，脉冲重复频率至少应该是最高多普勒频移的几倍

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SQL Error: select id,body,options from ***_enewstiku where sourceid='31794' and id < 2541795 and id<>'2541795' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='31794' and id > 2541795 and id<>'2541795' order by id asc limit 5