A.同頻B.同相C.同幅D.同頻同相
A.頻分多址B.時(shí)分多址C.碼分多址D.空分多址
A.數(shù)據(jù)結(jié)構(gòu)B.數(shù)據(jù)操作C.數(shù)據(jù)完整性約束D.數(shù)據(jù)存儲(chǔ)