Аңдатпа
Monitoring of oilfield well-head installations can be enhanced by Quadcopters equipped with video cameras flying at low altitude. Backhaul of a video stream from a Quadcopter's camera takes place via WiMAX base-stations within the installation. This paper considers a problem that arises: Video stream interruption as a handover occurs between WiMAX base-stations. The paper presents a scheme for hard handover recovery during video streaming to a remote monitoring station. The selective Negative ACKnowledgment (NACK) scheme trades a reduced but acceptable video quality during handover for improved end-to-end latencies compared to unselective NACKs. Both forms of NACK (selective and unselective) promise better video quality (by several dB) than with UDP transport or traditional congestion-controlled streaming, which results in long delays during handovers.