1 research outputs found
Practical Dynamic SC-Flip Polar Decoders: Algorithm and Implementation
SC-Flip (SCF) is a low-complexity polar code decoding algorithm with improved
performance, and is an alternative to high-complexity (CRC)-aided SC-List
(CA-SCL) decoding. However, the performance improvement of SCF is limited since
it can correct up to only one channel error (). Dynamic SCF (DSCF)
algorithm tackles this problem by tackling multiple errors (),
but it requires logarithmic and exponential computations, which make it
infeasible for practical applications. In this work, we propose simplifications
and approximations to make DSCF practically feasible. First, we reduce the
transcendental computations of DSCF decoding to a constant approximation. Then,
we show how to incorporate special node decoding techniques into DSCF
algorithm, creating the Fast-DSCF decoding. Next, we reduce the search span
within the special nodes to further reduce the computational complexity.
Following, we describe a hardware architecture for the Fast-DSCF decoder, in
which we introduce additional simplifications such as metric normalization and
sorter length reduction. All the simplifications and approximations are shown
to have minimal impact on the error-correction performance, and the reported
Fast-DSCF decoder is the only SCF-based architecture that can correct multiple
errors. The Fast-DSCF decoders synthesized using TSMC nm CMOS technology
can achieve a , and Gbps throughput for , respectively. Compared to the state-of-the-art fast CA-SCL decoders
with equivalent FER performance, the proposed decoders are up to
more area-efficient. Finally, observations at energy dissipation indicate that
the Fast-DSCF is more energy-efficient than its CA-SCL-based counterparts.Comment: Accepted for publication in IEEE TS