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Number of results: 5
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Abstract

This paper presents a novel low-complexity soft demapping algorithm for two-dimensional non-uniform spaced constellations (2D-NUCs) and massive order one-dimensional NUCs (1D-NUCs). NUCs have been implemented in a wide range of new broadcasting systems to approach the Shannon limit further, such as DVB-NGH, ATSC 3.0 and NGB-W. However, the soft demapping complexity is extreme due to the substantial distance calculations. In the proposed scheme, the demapping process is classified into four cases based on different quadrants. To deal with the complexity problem, four groups of reduced subsets in terms of the quadrant for each bit are separately calculated and stored in advance. Analysis and simulation prove that the proposed demapper only introduces a small penalty under 0.02dB with respect to Max-Log-MAP demapper, whereas a significant complexity reduction ranging from 68.75% to 88.54% is obtained.

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Authors and Affiliations

Chen Wang
Fang Wang
Mingqi Li
Jinfeng Tian
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Abstract

This article presents the results of the research of noiseimmunity of wireless communication systems using signals that are formed on the basis of eight-position quadrature-amplitude modulation (8-QAM) and eight-position amplitude modulation of many components (8-AMMC). The research was conducted using simulation of a wireless communication system, built using a detector, implemented on the basis of a phase locked loop. The influence of phase locked loop parameters on the detection quality of these signals in the condition of the interference in the communication channel was researched, and a comparative analysis of the noise immunity of wireless communication systems using these signals was carried out.

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Authors and Affiliations

Andriy P. Bondariev
Ivan V. Horbatyi
Ivan P. Maksymiv
Sergiy I. Altunin
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Abstract

In a massive multiple-input multiple-output (MIMO) system, a large number of receiving antennas at the base station can simultaneously serve multiple users. Linear detectors can achieve optimal performance but require large dimensional matrix inversion, which requires a large number of arithmetic operations. Several low complexity solutions are reported in the literature. In this work, we have presented an improved two-dimensional double successive projection (I2D-DSP) algorithm for massive MIMO detection. Simulation results show that the proposed detector performs better than the conventional 2D-DSP algorithm at a lower complexity. The performance under channel correlation also improves with the I2D-DSP scheme. We further developed a soft information generation algorithm to reduce the number of magnitude comparisons. The proposed soft symbol generation method uses real domain operation and can reduce almost 90% flops and magnitude comparisons.
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Authors and Affiliations

Sourav Chakraborty
1
Nirmalendu Bikas Sinha
2
Monojit Mitra
3

  1. Department of Electronics and Communication Engineering, Cooch Behar Government Engineering College, Coochbehar,India
  2. Principal, Maharaja Nandakumar Mahavidyalaya, Purba Medinipore, India
  3. Department of Electronics and Telecommunication, Engineering, IIEST Shibpur, Howrah, India
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Abstract

In this paper, the designing and simulation of 400 Gbps polarisation division multiplexing-quadrature amplitude modulation-orthogonal frequency division multiplexing (PDM-4QAM-OFDM)-based inter-satellite optical wireless communication (IsOWC)/mechatronic telecommunication system for improving the link information carrying capacity was carried out. With quadrature amplitude modulation (QAM) encoding, the performance of the executed system has been addressed using metrics such as signal to noise ratio (SNR) and total received power (RP). The performance with suggested system has been examined in relation to the effects of various factors such as operating wavelength, transmission power, and receiving pointing error angle. Moreover, a better identification method for improving connection reach between mechatronic devices/satellites has been revealed in this study. A performance comparison of the proposed system with other implemented approaches has been made in the final step
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Authors and Affiliations

Shivmanmeet Singh
1 2
Narwant Singh Grewal
2
Baljeet Kaur
2

  1. I. K. Gujral Punjab Technical University, Jalandhar – Kapurthala Highway, Kapurthala, 144603, Punjab, India
  2. Department of Electronics and Communication Engineering, Guru Nanak Dev Engineering College, Ludhiana, 141006, Punjab, India
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Abstract

Low Density Parity Check (LDPC) is a channel coding technique widely utilized in the 5G New Radio standard, it is of utmost importance in facilitating proficient and secure communication in noisy environments by effectively minimizing errors during data transmission. It is primarily used in the 5G New Radio (NR) standard for encoding user information on the Physical Downlink Shared Channel (PDSCH). The necessity to satisfy the increasing expectations for throughput, latency, and dependability led to the decision to deploy LDPC codes for user data, especially in the enhanced mobile broadband (eMBB) and ultra-reliable and low-latency communications (URLLC) scenarios of 5G networks. The present system proposes the use of NRLDPC codes for the purpose of transmitting data across a lognormal multipath fading channel model in the presence of AWGN. Wireless communication channels often use a lognormal multipath fading channel model, where the received signal experiences both multipath fading and lognormal shadowing. The research investigates the effectiveness of NR-LDPC coding in improving QAM-OFDM system performance by analyzing two rate-compatible base graphs and comparing their effectiveness with an uncoded system. This analysis is crucial for optimizing communication network design, especially in scenarios where the integrity of data is of utmost importance. We introduce a new method to improve the 5G NR LDPC code capability under lognormal fading conditions. This approach develops a layered Min Sum (LMS) algorithm to provide enhanced error correcting capabilities. The developed and implemented decoding algorithm represents a significant advancement over traditional detection methods. The outcomes of the simulation provide evidence of the effectiveness of the proposed NR-LDPC coding techniques in terms of their error correction and identification capabilities. In addition, the developed LMS decoding algorithm has been shown to significantly decrease the BER of the system.
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Authors and Affiliations

Mohammed Hussin Ali
Ghanim A. Al-Rubaye

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