In fading and shadowing channels,error control techniques are used for the reliable transmission. As a combination of forward error correction and automatic repeat request(ARQ),Hybrid ARQ(HARQ) protocol provides both of the advantages.

• 为了保证数据在无线衰落信道条件下的可靠传输,产生了联合前向纠错编码(FEC)与自动请求重传(ARQ)的混合ARQ(HARQ)技术。