  We propose in this paper a new coding scheme called twisted-pair
superposition transmission (TPST). The encoding is to "mix together" a pair of
basic codes by superposition, while the decoding can be implemented as a
successive cancellation list decoding algorithm. The most significant features
of the TPST code are its predictable performance that can be estimated
numerically from the basic codes and its flexible construction in the sense
that it can be easily adapted to different coding rates. To construct good TPST
codes in the finite length regime, we propose two design approaches-rate
allocation and partial superposition. By taking tail-biting convolutional codes
(TBCC) as basic codes, we show by numerical results that the TPST codes can
have near-capacity performance in the short length regime.
