短語詞組短語frequency -diversity spread spectrum 頻率分集擴(kuò)頻frequency difference diversity radar 頻率分集雷達(dá)frequency y diversity radars 頻率分集雷達(dá)frequency difference diversity 頻率分隔frequency difference diversity bandwidth 頻率分集帶寬frequency y diversity 頻率分集orthogonal frequency -diversity multiplexing 正交頻率差異多路 返回 frequency diversity