5 research outputs found
Design of Soft Viterbi Algorithm Decoder Enhanced With Non-Transmittable Codewords for Storage Media
Viterbi Algorithm Decoder Enhanced with Non-transmittable Codewords is one of
the best decoding algorithm which effectively improves forward error correction
performance. HoweverViterbi decoder enhanced with NTCs is not yet designed to
work in storage media devices. Currently Reed Solomon (RS) Algorithm is almost
the dominant algorithm used in correcting error in storage media. Conversely,
recent studies show that there still exist low reliability of data in storage
media while the demand for storage media increases drastically. This study
proposes a design of the Soft Viterbi Algorithm decoder enhanced with
Non-transmittable Codewords (SVAD-NTCs) to be used in storage media for error
correction. Matlab simulation was used in this design in order to investigate
behavior and effectiveness of SVAD-NTCs in correcting errors in data retrieving
from storage media.Sample data of one million bits are randomly generated,
Additive White Gaussian Noise (AWGN) was used as data distortion model and
Binary Phase- Shift Keying (BPSK) was applied for simulation modulation.
Results show that,behaviors of SVAD-NTC performance increase as you increase
the NTCs, but beyond 6NTCs there is no significant change and SVAD-NTCs design
drastically reduce the total residual error from 216,878 of Reed Solomon to
23,900
Bandwidth Aware FEC Algorithms for Wireless Communication Systems
Forward Error Correction (FEC) codes used by receivers to correct transmission errors without retransmission add a considerable amount of redundant bits to data bits. The addition of redundant bits lowers the overall network throughput, thus increasing the demand for more required bandwidth. In this paper we investigate and discuss various techniques used in FEC and show their effects to data communication in terms of bandwidth utilization. Additionally we propose improvement of (2, 1, 2) Convolutional encoder to (3, 2, 3) encoder. The proposed improvements increase the code rate from 1/2 to 2/3 hence reducing error control information and increasing bit rate. The received codeword can be decoded by Soft-Output Viterbi Algorithm. Keywords: FEC, Bandwidth, Convolutional Codes, Code Rate, Soft Output Viterbi Algorith
Performance of Soft Viterbi Decoder enhanced with Non-Transmittable Codewords for storage media
The introduction of Non-Transmittable Codewords (NTCs) into Viterbi Algorithm Decoder has emerged as one of the best ways of improving performance of the Viterbi Algorithm Decoder. However, the performance has been tested only in hard decision Viterbi Decoder in telecommunication systems, but not in soft decision Viterbi Decoder and storage media. Most storage media use Reed Solomon (RS) Algorithm Decoder. Yet, the field experience still shows failure of the algorithm in correcting burst errors in reading data from the storage media; leading into data loss. This paper introduces the Soft Viterbi Algorithm Decoding enhanced with Non-Transmittable Codewords for storage media. Matlab software was used to simulate the algorithm and the performance was measured by comparing residual errors in a data length of one million bits. Additive White Gaussian Noise model was applied to distort the stored data. The performance comparison was made against the Reed Solomon code, Normal Soft Viterbi and Hard decision Viterbi enhanced with NTCs. The results showed that the Soft Viterbi Algorithm enhanced with NTCs performed remarkably better by 88.98% against RS, 84.31% against Normal Soft Viterbi and 67.26% against Hard Viterbi enhanced with NTCs
Forward Error Correction for Storage Media: An Overview
Research Article published byInternational Journal of Computer Science and Information Security (IJCSIS), Vol. 13, No. 12, December 2015As the adoption of Information and Communication
Technology (ICT) tools in production and service rendering
sectors increases, the demand for digital data storage with large
storage capacity also increases. Higher storage media systems
reliability and fault tolerance are among the key factors that the
existing systems sometimes fail to meet and therefore, resulting
into data loss. Forward error correction is one of the techniques
applied to reduce the impact of data loss problem in digital data
storage. This paper presents a survey conducted in different
digital data storage companies in Dar es Salam, Tanzania. Data
were collected and analyzed using Statistical Package for Social
Sciences (SPSS). Secondary data were captured from user and
manufacturer technical reports. It was revealed that data loss is
still a predominant challenge in the digital data storage industry.
Therefore, the study proposes the new storage media FEC model
using locked convolutional encoder with the enhanced NTCViterbi
decoder
A review on deep learning aided pilot decontamination in massive MIMO
AbstractIn multi-antenna systems, advanced techniques such as massive multiple-input multiple-output (MIMO), beamforming, and beam selection depend heavily on the accurate acquisition of the channel state. However, pilot contamination (PC) can be a major source of interference which degrades they are performance. Moreover, the severity of PC increases as more pilots are reused between users in the wireless systems. Researchers have shown that PC can be mitigated by using deep learning (DL) approaches. Nevertheless, when minimizing PC, the examination that identifies the applications and factors that distinguish these DL approaches is still limited. This paper reviews these DL approaches and the improvements needed to enhance their performance. Simulation results confirm that DL networks that learn to predict the channels directly have superior performance under PC