ARQ schemes with switched antenna diversity and their applications in JPEG image transmission

Abstract

Automatic repeat request (ARQ) schemes provide means of transmitting data very reliably. ARQ protocols employ an error detection code and a feedback channel so that the receiver can request retransmission of the erroneous packets, or it can use the feedback channel to acknowledge the correctly received packets. Applications such as image and video usually require very low transmission bit error rates (<10/sup -7/) and achieving these low bit error rates in wireless channels is very challenging. We present an ARQ scheme with switched transmitter antenna diversity. In very slow fading channels, this scheme improves the throughput efficiency of the ARQ protocol significantly. The diversity benefit obtained from this scheme reduces the delay in transmitting the data packets and this is attractive in applications such as audio, image and real-time video. We also use this scheme to transmit JPEG coded images.