Performance Analysis of Cyclostationary Interference Suppression for Multiuser Wired Communication Systems

Im, Gi-Hong,Won, Hui-Chul The Korea Institute of Information and Commucation 2004 Journal of communications and networks Vol.6 No.2

This paper discusses cyclostationary interference suppression for multiuser wired communication systems. Crosstalk interference from digital signals in multipair cables has been shown to be cyclostationary. Many crosstalk equalization or suppression techniques have been proposed which make implicit use of the cyclostationarity of the crosstalk interferer. In this paper, the convergence and steady-state behaviors of a fractionally spaced equalizer (FSE) in the presence of multiple cyclostationary crosstalk interference are thoroughly analyzed by using the equalizer's eigenstructure. The eigenvalues with multiple cyclostationary interference depend upon the folded signal and interferer power spectra, the cross power spectrum between the signal and the interferer, and tile cross power spectrum between the interferers, which results in significantly different initial convergence and steady-state behaviors as compared to the stationary noise case. The performance of the equalizer varies depending on the relative clock phase of the symbol clocks used by the signal and multiple interferers. Measued characteristics as well as analytical model of NEXT/FEXT channel are used to compute the optimum and worst relative clock phases among the signal and multiple interferers.

무선센서네트워크를 위한 신호 에너지 기반 사이클로스테이셔너리 스펙트럼 검출

Quoc Kien Nguyen,전태현 한국위성정보통신학회 2016 한국위성정보통신학회논문지 Vol.11 No.3

특징 검출 기법은 원하는 신호에 대한 부분적인 정보가 수신단에 알려진 상황에서 정확도 높은 검출이 가능한 기법으로 알려져 있다. 이러한 방식의 검출 기법은 잡음이 강한 환경을 위해 제안되었다. 사이클로스테이셔너리 검출은 인지 무선 시스템에서 스펙트럼 검출 기법의 하나의 예이다. 그러나 이 기법은 원하는 신호에 대한 많은 양의 정보와 처리 시간을 요구한다. 반면, 에너지 검출 기반 의 스펙트럼 검출은 단순한 기법으로 널리 알려져 있다. 그러나 에너지 검출은 잡음의 영향을 많이 받으며 이로 인한 검출 오류가 많이 발생하게 된다. 본 논문에서는 에너지와 사이클로스테이셔너리 기반의 기법을 결합하여 검출의 정확도를 높이는 한편 계산량 과 처리 시간을 감소시키는 기법을 제안한다. 2단계의 문턱값을 이용하여 사이클로스테이셔너리 기법의 복잡도와 처리시간을 단축 하여 시스템의 전송 효율을 증가시킨다. 시뮬레이션 결과 에너지 기반 사이클로스테이셔너리 검출 기법은 신호 검출에 소요되는 시간을 상당히 감소시키는 반면 시스템의 성능을 향상시킴을 보여준다. Feature detection is recognized as an accurate spectrum sensing approach when the information of the desired signal is partly known at the receiver. This type of detection was proposed to overcome large noise environment. Cyclostationary detection is an example of feature detection in spectrum sensing technique in cognitive radio. However, the cyclostationary process calculation requires a lot of processing time and information about the designed signals. On the other hand, energy detection spectrum sensing is widely known as a simple and compact spectrum sensing technique. However, energy detection is highly affected by large noise and lead to high detection error probability. In this paper, the combination of energy detection and cyclostationary is proposed in order to increase the accuracy and decrease the calculation and processing time. The two-layer threshold is utilized in order to reduce the complexity of computation and processing time in cyclostationary which can lead to the improved throughput of the system. The simulation result shows that the implementation of energy-based cyclostationary detector can help to improve the performance of the system while it can considerably reduce the required time for signal detection.

Signal Energy-based Cyclostationary Spectrum Sensing for Wireless Sensor Networks

Quoc Kien Nguyen,전태현 사단법인 한국위성정보통신학회 2016 한국위성정보통신학회논문지 Vol.11 No.3

Feature detection is recognized as an accurate spectrum sensing approach when the information of the desired signal is partly known at the receiver. This type of detection was proposed to overcome large noise environment. Cyclostationary detection is an example of feature detection in spectrum sensing technique in cognitive radio. However, the cyclostationary process calculation requires a lot of processing time and information about the designed signals. On the other hand, energy detection spectrum sensing is widely known as a simple and compact spectrum sensing technique. However, energy detection is highly affected by large noise and lead to high detection error probability. In this paper, the combination of energy detection and cyclostationary is proposed in order to increase the accuracy and decrease the calculation and processing time. The two-layer threshold is utilized in order to reduce the complexity of computation and processing time in cyclostationary which can lead to the improved throughput of the system. The simulation result shows that the implementation of energy-based cyclostationary detector can help to improve the performance of the system while it can considerably reduce the required time for signal detection.

LTE 시스템을 위한 Cyclostationary 신호 검출 기법의 성능 분석

김승종,김경호,황유민,김진영 통신위성ㆍ우주산업연구회 2014 한국위성정보통신학회논문지 Vol.9 No.2

본 논문에서는 LTE 시스템을 위한 Cyclostationary 신호 검출 기법의 성능을 분석하였다. 스펙트럼 사용 효율을 높이고 주파수를 공유하는 인지무선(Cognitive radio, CR)기술에 Cyclostationary 신호검출 기법을 적용하여, Long term evolution(LTE) 환경의 주파 수 대역 내에서 신호를 검출하였다. LTE 시스템은 3rd generation partnership project(3GPP)에서 최대 전송률을 높이고, 낮은 지연을 제공하기 위한 표준으로 지정되었다. 본 논문에서는 하향링크 직교 주파수 분할 다중 접속(Orthogonal frequency division multiple access, OFDMA) 신호를 기준으로 LTE 신호를 생성하였으며, 생성된 신호의 Segment 및 임계값에 따라 검출성능을 분석하였다. 모의실험에 적용된 채널은 가우시안 채널이고, 추후 LTE 시스템에 CR을 적용하기 위한 향후 연구 방향에 대하여 논의하였다.

가산성 주기정상성 잡음이 있을 때 Zero Forcing 기반에서의 송수신단 동시 최적화

윤여훈,조준호,Yun, Yeo-Hun,Cho, Joon-Ho 한국통신학회 2007 韓國通信學會論文誌 Vol.32 No.7a

In this paper, we consider a joint optimization of transmitter and receiver in additive cyclostationary noise with zero forcing criterion. We assume that the period of the cyclostationary noise is the same as the inverse of the symbol transmission rate and that the noise has a positive-definite autocorrelation function. The data sequence is modeled as a wide-sense stationary colored random process and the channel is modeled as a linear time-invariant system with a frequency selective impulse response. Under these assumptions and a constraint on the average power of the transmitted signal, we derive the optimum transmitter and receiver waveforms that jointly minimizes the mean square error with no intersymbol interference. The simulation results show that the proposed system has a better BER performance than the systems with receiver only optimization and the systems with no transmitter and receiver optimization. 가산성 주기정상성 잡음이 있을 때 zero forcing (ZF) 기반에서의 송수신단 동시 최적화를 고려한다. 주기정상성 잡음의 주기는 심볼 전송율의 역수라고 가정하고 자기 상관함수는 양의 정부호로 가정한다. 전송되는 데이터 수열은 광의의정상성(WSS: wide-sense stationary)을 가지는 유색 확률과정으로 모델링 하고 채널은 주파수 선택적 충격 응답을 가지는 선형 시불변 시스템으로 모델링 한다. ZF와 송신 전력 제약 아래 평균제곱오차 (MSE: mean square error)를 최소화하는 최적 송수신 파형을 유도하고 모의 실험 결과를 통해 수신파형만 최적화 한 경우와 가산성 주기정상성 잡음을 정상성 잡음으로 간주한 경우 보다 성능이 더 좋아짐을 보인다.

OFDM system with cyclostationary feature detection spectrum sensing

Arun Kumar,NandhaKumar P. 한국통신학회 2019 ICT Express Vol.5 No.1

In Orthogonal Frequency Division Multiplexing OFDM, a cyclic prefix (CP) is applied to reduce the intervention between symbols. The CP results in bandwidth wastage, and the solution to this problem leads to the cognitive radio. In the first part of the work, OFDM with CP is presented and integrated with cyclostationary spectrum sensing. Subsequently, OFDM with cyclostationary spectrum sensing without CP is proposed with the function of the filter at the transmitter and receiver being to utilize the bandwidth that is wasted in the CP phase. The Bit Error Rate BER, signal probability detection, false alarm, and error probability are obtained and analyzed.

A novel fault diagnosis method based on EMD, cyclostationary, SK and TPTSR

Yijie Niu,Jiyou Fei,Yuanyuan Li,Deng Wu 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.5

A novel method based on empirical model decomposition (EMD), cyclostationary, spectral kurtosis (SK) and two-phase test sample sparse representation (TPTSR), called ECK-TPTSR is proposed for fault diagnosis in this paper. In the ECK-TPTSR method, the vibration signal is decomposed into several components by EMD. Then each component can be modelled as cyclostationary for noise reduction. Next, the proposed method computes the kurtosis of the unbiased autocorrelation on the squared envelope of each component, and extracts the component with the highest kurtosis. Finally, the extracted component is used to construct training samples and test samples, which are input into the TPTSR classifier to fulfill fault classification accurately. Moreover, the experimental results indicate that the ECK-TPTSR method can effectively achieve fault diagnosis of motor bearing and obtain higher classification accuracy.

Weak fault detection for wind turbine bearing based on ACYCBD and IESB

Xiaolong Wang,Xiaoli Yan,Yuling He 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.4

To detect the rolling bearing fault of a wind turbine at incipient injury phase, a novel method combining adaptive cyclostationary blind deconvolution (ACYCBD) with instantaneous energy slice bispectrum (IESB) is proposed. Cuckoo search algorithm (CSA) is fused with cyclostationary blind deconvolution (CYCBD) to optimize cyclic frequency and filter length parameters, and the satisfied processing result is able to adaptively use this developed ACYCBD method. Besides, fusing the complementary superiorities of frequency weighted energy operator and slice bispectrum, a new frequency domain analysis method named IESB is put forward to identify the characteristic frequency components. During fault diagnosis, the deconvolution signal with higher signal to noise ratio is first separated from the collected signal by applying ACYCBD method. However, owing to the intense background noises, external interferences still remain in the deconvolution signal. Then the IESB is further used as a post-processing method, the residual noises are suppressed effectively, and the characteristic spectral lines are highlighted immensely. In the end, the incipient fault injury of wind turbine bearing can be diagnosed by analyzing the acquired instantaneous energy slice bispectrum. The analyzed results of wind turbine bearing fault signals from the experimental rig and the actual engineering testing field demonstrate the feasibility and the superiority of this novel detection method.

A Flexible Data-Driven Cyclostationary Model for the El Niño Southern – Oscillation

Roman Olson,Yanan Fan,Soon-Il An,Soong-Ki Kim 한국기상학회 2022 한국기상학회 학술대회 논문집 Vol.2022 No.4

WiBro 시스템을 위한 인지무선 Cyclostationary 스펙트럼 센싱 성능

구성완,김진영 한국정보통신설비학회 2009 정보통신설비학회논문지 Vol.8 No.3