Novel Joint Estimation and Decoding Metrics for Short-Blocklength Transmission Systems
Abstract:
This paper presents Bit-Interleaved Coded Modulation metrics for joint estimation detection using training or
reference signal transmission strategies for short to long block
length channels. We show that it is possible to enhance the
performance and sensitivity through joint detection-estimation
compared to standard receivers, especially when the channel
state information is unknown and the density of the training
dimensions is low. The performance analysis makes use of a
full 5G transmitter and receiver chains for both Polar and
LDPC coded transmissions paired with BPSK/QPSK modulation
schemes. We consider transmissions where reference signals
are interleaved with data and both are transmitted over a
small number of OFDM symbols so that near-perfect channel
estimation cannot be achieved. Our findings demonstrate that
when the detection windows used in the metric units is on the
order of four modulated symbols the proposed BICM metrics
can be used to achieve detection performance that is close to that
of a coherent receiver with perfect channel state information for
both polar and LDPC coded configurations. Furthermore, we
show that for transmissions with low DMRS density, a good
trade-off can be achieved in terms of additional coding gain and
improved channel estimation quality by adaptive DMRS power
adjustment.
keyword :Bit-Interleaved Coded Modulation, 5G NR Polar code, 5G NR LDPC Code, Unknown Channel State Information, Joint Estimation and Detection.