  This paper studies the performance of backscatter communications (BC) over
emerging fluid antenna (FA) technology. In particular, a single-antenna source
sends information to a FA reader through the wireless forward (i.e.,
source-to-tag) and backscatter (tag-to-reader) channels. For the considered BC,
we first derive the cumulative distribution function (CDF) of the equivalent
channel at the FA receiver, and then we obtain closed-form expressions of the
outage probability (OP) and delay outage rate (DOR) under a correlated Rayleigh
distribution. Moreover, in order to gain more insights into the system
performance, we present analytical expressions of the OP and DOR at the high
SNR regime. Numerical results indicate that considering the FA at the reader
can significantly improve the performance of BC in terms of the OP and DOR
compared with a single-antenna reader.
