Performance analysis and comparison of HARQ schemes in cross layer design

This paper is concerned with a cross-layer design combining adaptive modulation and coding (AMC) at the physical layer with hybrid automatic repeat request (HARQ) at the data link layer (LL) based on the rate compatible convolutional codes. In order to satisfy the prescribed delay and packet error rate (PER) constraints at LL, as well as to maximize the spectral efficiency, we apply the type-II and type-III HARQ to the cross layer design framework. We have derived the closed-form expression of the PER and average spectral efficiency for the transmissions over Nakagami-m communication channel. Numerical results show that the application of the type-III HARQ could achieve the highest spectral efficiency and the lowest PER, but it is the most complex. The type-I HARQ has the lowest spectral efficiency and the highest PER, but it has the lowest complexity. Meanwhile the type-II HARQ has a compromise between them.