無線通道由於受到多重路徑干擾的影響而造成嚴重的通道衰減，使用時間或頻率的分集為有效減緩通道衰減的技術。許多文獻證明了多重輸入多重輸出(MIMO)系統除了可以經由空間分集來抵抗通道衰減，同時也能增加系統的容量，這些研究引發了空時碼的研究，空時碼結合了通道編碼與多傳輸天線設計而能有效應用於多路徑干擾之無線通道。 在文獻中提出了時空區段碼(Space Time Block Codes)，在給定數目的天線條件下，能獲得分集增益與編碼增益。由於通道受到多重路徑干擾的影響，在接收端必需使用RAKE或是Equalizer來對接收訊號做通道補償，藉由本研究，我們希望可以設計出具有分集增益與優越補償訊號的通訊系統。 Wireless transmission over multipath channel usually suffers severe attenuation. The Effective techniques to mitigate multipath fading are time and frequency diversity. Researchers have proved that multiple-input multiple-output can introduce spatial diversity to increase information capacity. These results motivate a new study in error correcting codes. Space-Time Coding (STC) schemes can combine the channel code design and the use of multiple transmit antennas. The Space-Time Block Code (STBC) techniques combine the trellis coding with symbol mapping into multiple transmitted antennas. The Coding scheme expansion is done in antenna space. Signal transmitted over multipath fading channel, the received signal must be applied RAKE or Equalizer to overcome the channel effect. At this study, we expect to design a communication system compromised diversity gain and with good channel compensation.
