Zobrazeno 1 - 10
of 245
pro vyhledávání: '"Chang-Jun AHN"'
Publikováno v:
ICT Express, Vol 9, Iss 1, Pp 57-62 (2023)
Spectrum sharing in the spatial domain among the plurality of wireless communication systems should be addressed due to its exhaustion. We previously conceptualized a spectrum superposing enabled by subcarrier transmission power assignment (STPA) and
Externí odkaz:
https://doaj.org/article/a189a1affe144ac3a56d3cebbb437735
Publikováno v:
Journal of Communications Software and Systems, Vol 18, Iss 4, Pp 343-349 (2022)
The effect of additive noise on the channel state information (CSI) quality is a crucial issue in mobile communication systems. The adaptive subcarrier grouping (ASG) for sample matrix inversion (SMI) based minimum mean square error (MMSE) adaptive a
Externí odkaz:
https://doaj.org/article/2b1c67e286be4774843b2299c800a980
Publikováno v:
IEEE Access, Vol 9, Pp 18361-18372 (2021)
Inter-user interference (IUI) suppression is a prime matter for mobile communication systems. Channel state information (CSI), meanwhile, is severely affected by the receiver additive noise effect. Sample matrix inversion (SMI) based minimum mean squ
Externí odkaz:
https://doaj.org/article/410a1598212243bdbdf551cc15c77f57
Publikováno v:
IEEE Access, Vol 9, Pp 142425-142436 (2021)
In the high mobility environment, the channel state information (CSI) in the last part of the packet is different from the beginning part’s actual channel. This phenomenon degrades channel estimation accuracy, and hence it is necessary to be compen
Externí odkaz:
https://doaj.org/article/4b7f1eee8a074a3895b3a4a1f36d4366
Publikováno v:
ICT Express, Vol 6, Iss 3, Pp 249-252 (2020)
This article proposes a novel wireless channel estimation method suited for fast fading environment. Generally, forward error correction (FEC) requires long block code length to raise error correction capability while it deteriorates the channel trac
Externí odkaz:
https://doaj.org/article/1cd12a51f0aa49ba8597ade3d1c4c7e3
Publikováno v:
IEEE Access, Vol 8, Pp 224292-224305 (2020)
This article proposes a novel postcoding design scheme for suppressing inter-user interference (IUI) and inter-cell interference (ICI) in uplink multiuser massive multiple-input multiple-output (MIMO) system in time-varying channel environments. In t
Externí odkaz:
https://doaj.org/article/d050b76e2a254c1fbad1cb863d7574d8
Publikováno v:
ICT Express, Vol 5, Iss 4, Pp 261-265 (2019)
Due to large peak-to-average power ratio (PAPR) at the time domain OFDM signal, various peak signal reduction methods for OFDM systems have been proposed. However, in a transmit OFDM beamforming, multiplication of the transmit signal using the weight
Externí odkaz:
https://doaj.org/article/191c3b4f65b642049f8feccaa68617c6
Publikováno v:
ICT Express, Vol 5, Iss 4, Pp 271-275 (2019)
This paper newly proposes a direct antenna array control approach to reduce channel spatial correlation for multiuser spatial multiplexing. Conventional rectangular arrays can form three dimensional beams and have superior signal separation performan
Externí odkaz:
https://doaj.org/article/754d24e4e41a404eba4a9b82c38d245f
Publikováno v:
ICT Express, Vol 5, Iss 4, Pp 276-279 (2019)
This paper proposes a modified pilot selection for channel estimation of systematic polar coded MIMO-OFDM. Polar codes provably achieve the theoretical limit for communication systems and systematic polar codes generate the codeword that has the same
Externí odkaz:
https://doaj.org/article/c80e8a3ddc38436aba119a1a36f998a5
Publikováno v:
IEEE Access, Vol 7, Pp 183545-183553 (2019)
In this paper, we propose a novel Adaptive Modulation and Coding (AMC) scheme enabled by Artificial Neural Network (ANN) aided Signal-to-Noise power Ratio (SNR) estimation. The Power Spectral Density (PSD) values are trained for SNR classification an
Externí odkaz:
https://doaj.org/article/2aa11aa9cadb49bc81151f4c3be7971f