CAAHR: Content aware adaptive HARQ retransmission scheme for 4G/LTE network

A drastic increase in traffic of mobile broadband is seen in the past few years, which is further accelerated by the increased usage of smart phones and its applications. The availability of good smart phones and better data connectivity are encouraging mobile users to use video services. This huge increase in usage will pose a lot of challenges to the wireless networks. The existing wireless networks lack content awareness within an application. In this paper, we present an approach to content awareness at the Hybrid Automatic Repeat reQuest (HARQ) level of Long Term Evolution (LTE) system by changing the retransmission count based on the importance of packet being scheduled. This scheme improves the received video quality by up to 8% for users under poor channel conditions with negligible increase in packet delay and Physical Downlink Shared Channel (PDSCH) utilization factor. The main benefits of this scheme are its simplicity and ease of implementation without compromising on performance of the network elements.