常见例句The author has described several key techniques for improving the capacity of CDMA digital celullar system,comparing to the spectral efficiency of FDMA and TDMA cellular system.本文對照頻分多址和時分多址系統的頻譜傚率，闡述了碼分多址系統提高系統容量的幾項關鍵技術。 返回 TDMA