126 research outputs found
Comparison of Polar Decoders with Existing Low-Density Parity-Check and Turbo Decoders
Polar codes are a recently proposed family of provably capacity-achieving
error-correction codes that received a lot of attention. While their
theoretical properties render them interesting, their practicality compared to
other types of codes has not been thoroughly studied. Towards this end, in this
paper, we perform a comparison of polar decoders against LDPC and Turbo
decoders that are used in existing communications standards. More specifically,
we compare both the error-correction performance and the hardware efficiency of
the corresponding hardware implementations. This comparison enables us to
identify applications where polar codes are superior to existing
error-correction coding solutions as well as to determine the most promising
research direction in terms of the hardware implementation of polar decoders.Comment: Fixes small mistakes from the paper to appear in the proceedings of
IEEE WCNC 2017. Results were presented in the "Polar Coding in Wireless
Communications: Theory and Implementation" Worksho
VLSI implementation of a multi-mode turbo/LDPC decoder architecture
Flexible and reconfigurable architectures have gained wide popularity in the communications field. In particular, reconfigurable architectures for the physical layer are an attractive solution not only to switch among different coding modes but also to achieve interoperability. This work concentrates on the design of a reconfigurable architecture for both turbo and LDPC codes decoding. The novel contributions of this paper are: i) tackling the reconfiguration issue introducing a formal and systematic treatment that, to the best of our knowledge, was not previously addressed; ii) proposing a reconfigurable NoCbased turbo/LDPC decoder architecture and showing that wide flexibility can be achieved with a small complexity overhead. Obtained results show that dynamic switching between most of considered communication standards is possible without pausing the decoding activity. Moreover, post-layout results show that tailoring the proposed architecture to the WiMAX standard leads to an area occupation of 2.75 mm2 and a power consumption of 101.5 mW in the worst case
Flexible LDPC Decoder Architectures
Flexible channel decoding is getting significance with the increase in number of wireless standards and modes within a standard. A flexible channel decoder is a solution providing interstandard and intrastandard support without change in hardware. However, the design of efficient implementation of flexible low-density parity-check (LDPC) code decoders satisfying area, speed, and power constraints is a challenging task and still requires considerable research effort. This paper provides an overview of state-of-the-art in the design of flexible LDPC decoders. The published solutions are evaluated at two levels of architectural design: the processing element (PE) and the interconnection structure. A qualitative and quantitative analysis
of different design choices is carried out, and comparison is provided in terms of achieved flexibility, throughput, decoding efficiency, and area (power) consumption
Configurable LDPC Decoder Architecture for Regular and Irregular Codes
Low Density Parity Check (LDPC) codes are one of the best error correcting codes that enable the future generations of wireless devices to achieve higher
data rates with excellent quality of service. This paper presents two novel flexible decoder architectures. The first one supports (3, 6) regular codes of rate 1/2 that can be used for different block lengths. The second decoder is more general and supports both regular and irregular LDPC codes with twelve combinations of code lengths −648, 1296, 1944-bits and code rates-1/2, 2/3, 3/4, 5/6- based on the IEEE 802.11n standard. All codes correspond to a block-structured parity check matrix, in which the sub-blocks are either a shifted identity matrix or a zero matrix. Prototype architectures for both LDPC decoders have been implemented and tested on a Xilinx field programmable gate array.NokiaNational Science Foundatio
Scalable and Low Power LDPC Decoder Design Using High Level Algorithmic Synthesis
This paper presents a scalable and low power low-density parity-check (LDPC) decoder design for the next generation wireless handset SoC. The methodology is based on high level synthesis: PICO (program-in chip-out) tool was used to produce efficient RTL directly from a sequential untimed C algorithm. We propose two parallel LDPC decoder architectures: (1) per-layer decoding architecture with scalable parallelism, and (2) multi-layer pipelined decoding architecture to achieve higher throughput. Based on the PICO technology, we have implemented a two-layer pipelined decoder on a TSMC 65nm 0.9V 8-metal layer CMOS technology with a core area of 1.2 mm2. The maximum achievable throughput is 415 Mbps when operating at 400 MHz clock frequency and the estimated peak power consumption is 180 mW.NokiaNokia Siemens Networks (NSN)XilinxNational Science Foundatio
A LOW-POWER 1-Gbps RECONFIGURABLE LDPC DECODER DESIGN FOR MULTIPLE 4G WIRELESS STANDARDS
In this paper we present an efficient system-on-chip implementation of a 1-Gbps LDPC decoder for 4G (or beyond 3G) wireless standards. The decoder has a scalable data path and can be dynamically reconfigured to support multiple
4G standards. We utilize a pipelined version of the layered belief propagation algorithm to achieve partial-parallel decoding of structured LDPC codes. Instead of using the sub-optimal Minsum algorithm, we propose to use the powerful belief propagation (BP) decoding algorithm by designing an area-efficient soft-input soft-output (SISO) decoder. Two power saving schemes
are employed to reduce the power consumption up to 65%. The decoder has been synthesized, placed, and routed on a TSMC 90nm 1.0V 8-metal layer CMOS technology with a total area of 3.5 mm2. The maximum clock frequency is 450 MHz and the estimated peak power consumption is 410 mW.NokiaNational Science Foundatio
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