Spatiotemporal 2-D Channel Coding for Very Low Latency Reliable MIMO Transmission

Abstract

To fully support vertical industries, 5G and its corresponding channel coding are expected to meet requirements of different applications. However, for applications of 5G and beyond 5G (B5G) such as URLLC, the transmission latency is required to be much shorter than that in eMBB. Therefore, the resulting channel code length reduces drastically. In this case, the traditional 1-D channel coding suffers a lot from the performance degradation and fails to deliver strong reliability with very low latency. To remove this bottleneck, new channel coding scheme beyond the existing 1-D one is in urgent need. By making full use of the spacial freedom of massive MIMO systems, this paper devotes itself in proposing a spatiotemporal 2-D channel coding for very low latency reliable transmission. For a very short time-domain code length N time = 16, 64×128 MIMO system employing the proposed spatiotemporal 2-D polar channel coding scheme successfully shows more than 3 dB performance gain at FER = 10 −3 , compared to the 1-D time-domain channel coding. It is noted that the proposed coding scheme is suitable for different channel codes and enjoys high flexibility to adapt to difference scenarios. By appropriately selecting the code rate, code length, and the number of codewords in the time and space domains, the proposed coding scheme can achieve a good tradeoff between the transmission latency and reliability.

Closed-form Approximation for Performance Bound of Finite Blocklength Massive MIMO Transmission

“…which illustrates that latency is inversely proportional to the spatial DoF. This scaling law is just the basic principle behind the 2D channel coding presented in [10]. And, Eq.…”

“…With limited training and feedback overheads, joint uplink and downlink URLLC transmission method is studied in [9] to reduce error probability and improve reliability. In order to relieve the performance degradation resulted from applying conventional channel coding to URLLC short-packet transmission, a spatiotemporal 2-D channel coding scheme is proposed for very low latency reliable data transmission [10]. Enabled by the spatial freedom of massive MIMO, the proposed coding scheme in [10] can flexibly balance transmission reliability and latency for different scenarios.…”

On the Road to 6G: Visions, Requirements, Key Technologies, and Testbeds

“…Another promising solution for short-length scenarios is to use concatenated codes, like Arkans new polarizationadjusted convolutional (PAC) codes [394]. By fully exploiting the massive antennas in MIMO systems, a spatiotemporal 2-D coding scheme concatenates codes from the time domain to the space domain, to improve the reliability and transmission rate in a short decoding latency [395].…”

Toward 6G TK$μ$ Extreme Connectivity: Architecture, Key Technologies and Experiments

“…On the other hand, as hundreds of antennas are employed in the cell-free massive MIMO system, the extra degree of freedom in the space domain can be fully utilised, and this motivates us to propose the spatiotemporal 2-D channel coding scheme. In the rest part of this subsection, we will introduce this scheme for massive MUMO systems to support very low latency communication for 6G URLLC applications [49].…”