Antenna redundancy for increasing transmission reliability in wireless industrial LANs

Abstract — In this paper we introduce the concept of an-tenna redundancy, which uses different transmitter antennas for performing retransmissions, however, without transmitting in parallel over multiple antennas and therefore without requiring complex space-time processing techniques in receivers. This allows to keep receivers of small wireless field devices cheap. We investigate for certain wireless channel error scenarios the potential of this approach to transmit data within a prescribed deadline. This question is of utmost importance for wireless industrial communication systems. The results show that antenna redundancy not only reduces the probability of deadline miss ex-ponentially with increasing the number of antennas, furthermore it reduces the expected bandwidth needed to transmit data. I