單項(xiàng)選擇題
A.4B3Y B.4Y3B C.7單元恒比碼 D.ASCII
A.88 B.57 C.28 D.70
A.S/N=3dBEA=2uv B.S/N=6dBEA=2uv C.S/N=3dBEA=3uv D.S/N=6dBEA=3uv