Cross-Layer Optimization of Adaptive Multi-Rate Wireless Networks Using Truncated Chase Combining HARQ

A cross-layer performance analysis of a wireless network using adaptive modulation and coding at the physical layer and a truncated Chase combining hybrid automatic repeat request (HARQ-CC) scheme for error control at the data link layer is developed. Based on a Markov chain queueing model, analytical expressions for performance metrics such as throughput, average packet delay and packet loss rate are derived and then used to formulate a constrained optimization problem to maximize the system throughput under the prescribed Quality-of-Service constraints. Numerical results reveal that HARQ-CC consistently outperforms the classical Type-I Hybrid forward error correction/automatic repeat request schemes.