  In order to further enhance the particle identification capability of the
Beijing Spectrometer (BESIII), it is proposed to upgrade the current end-cap
time-of-flight (eTOF) detector with multi-gap resistive plate chamber (MRPC).
The prototypes, together with the front end electronics (FEE) and time
digitizer (TDIG) module have been tested at the E3 line of Beijing Electron
Positron Collider (BEPCII) to study the difference between the single and
double-end readout MRPC designs. The time resolutions (sigma) of the single-end
readout MRPC are 47/53 ps obtained by 600 MeV/c proton/pion beam, while that of
the double-end readout MRPC is 40 ps (proton beam). The efficiencies of three
MRPC modules tested by both proton and pion beam are better than 98%. For the
double-end readout MRPC, no incident position dependence is observed.
