Browsing by Author "Sun, Wei-Cheng"

Now showing 1 - 4 of 4

A 501mW 7.61Gb/s Integrated Message-Passing Detector and Decoder for Polar-Coded Massive MIMO Systems
(2017-01-01)
Chen, Yan-Tong
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Cheng, Chung-Chao
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Tsai, Tsung-Lin
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Sun, Wei-Cheng
;
Ueng, Yeong-Luh
This work presents the first integration of a message-passing detector (MPD) and a polar decoder. A soft-output MPD, which is essential to approach the channel capacity, is first proposed. Compared to the state-of-the-art design, the proposed MPD achieves a 6.9x higher throughput with 49% lower energy, despite the soft outputs. The proposed polar decoder achieves a 1.35x higher throughput with comparable energy. The chip delivers a throughput of 7.61Gb/s for massive MIMO systems with up to 128 antennas and 32 users.
A 794Mbps 135mW Iterative Detection and Decoding Receiver for 4x4 LDPC-Coded MIMO Systems in 40nm
(2015)
Wu, Wei-Hsuan
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Sun, Wei-Cheng
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Yang, Chia-Hsiang
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Ueng, Yeong-Luh
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交大名義發表
A low-density parity-check (LDPC)-coded multiple-input multiple-output (MIMO) systems with iterative detection and decoding (IDD) chip is integrated in 1.33mm(2) in 40nm CMOS. The maximum gross throughput is 794Mb/s for a 4x4 16-QAM configuration at 288MHz. The chip dissipates 135mW at 0.9V, achieving an energy efficiency of 170pJ/bit. Compared to non-IDD receivers, composed of state-of-the art MIMO detectors and LDPC decoders, this work achieves even higher area and energy efficiencies, despite the improved error performance.
An Integrated Message-Passing Detector and Decoder for Polar-Coded Massive MU-MIMO Systems
(2019-03-01)
Chen, Yan-Tong
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Sun, Wei-Cheng
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Cheng, Chung-Chao
;
Tsai, Tsung-Lin
;
Ueng, Yeong-Luh
For a coded massive multi-user multiple-input multiple-output (MIMO) system, a soft-output MIMO detector is essential since it can provide a significant coding gain, e.g., 3 dB, compared with a hard-output detector. However, the computational complexity of the soft-output MIMO detector is usually much greater than that of the hard-output detector. This paper presents the first soft-output message-passing detector (MPD), which is also integrated with a high-throughput polar decoder. The algorithm and architecture are designed concurrently to improve the hardware performance. The proposed techniques, including the adaptive variance estimation and reliable symbol detection, reduce the complexity of the MPD by 98.3%, and enable soft output for the outer polar decoder. Compared to the state-of-the-art hard-output design, the proposed MPD achieves a 5.86x higher throughput-to-area ratio (TAR) with 54.3% lower energy dissipation, despite the soft output. The proposed bidirectional-propagation belief propagation decoder is devised to reduce the critical path and to increase the throughput. The proposed polar decoder can improve the TAR by 35% with a comparable area and energy compared with the state-of-theart polar decoder. A polar-coded massive MIMO receiver that supports a length-1024 rate-1/2 polar code, 128 receive antennas, and eight users is designed and implemented, and delivers a throughput of 7.61 Gb/s.
Iterative Inter-Cell Interference Cancellation Receiver for LDPC-Coded MIMO Systems
(2019-03-15)
Sun, Wei-Cheng
;
Chen, Yan-Tong
;
Yang, Chia-Hsiang
;
Ueng, Yeong-Luh
;
電子工程學系及電子研究所
In an ultra-dense cellular system, users at the cell-edge are susceptible to inter-cell interference (ICI) because of the overlap of the spectrum. To combat ICI, this paper investigates two iterative ICI cancellation approaches for low-density parity-check-coded multiple-input multiple-output systems. One approach includes separate signal and interference detectors; the other one employs a joint detector for both the desired signal and interference. The joint-detector approach achieves a comparable error-rate performance with only half the computational complexity when compared to the separate-detector counterpart. An iterative ICI cancellation receiver using the joint detector is proposed and implemented. Its hardware efficiency is significantly enhanced by leveraging an efficient coordinate rotation digital computer based processing array, an adaptive input-range scaling scheme, and an area-efficient log-likelihood ratio calculator. The iterative ICI cancellation receiver is flexible enough to support multiple modulations of up to 256-QAM. The maximum gross throughput is 1.24 Gb/s for a 4x4 256-QAM configuration in a 40-nm CMOS technology. The proposed iterative receiver outperforms the current state-of-the-art works in both the throughput-to-area ratio and the normalized energy metrics, despite the added ICI capability.