短語詞組短語backfire helical antenna 回火螺線天線;背射模螺旋天線A New Backfire Antenna 一種新式背射天線a backfire antenna 背射式天線Backfire feed Cassegrain antenna 背射饋源卡氏天線ANALYSIS OF SHORT BACKFIRE ANTENNA 短背射天線分析A BROAD -BAND BACKFIRE ANTENNA 寬頻帶背射天 返回 backfire antenna