• Title/Summary/Keyword: bit error rate

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Hybrid decision decoding for the extended hamming codes (확대 Hamming 부호에 대한 혼합판정 복호기법)

  • 정창기;이응돈;김정구;주언경
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.33A no.2
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    • pp.32-39
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    • 1996
  • Hybrid decision decoding for the extended hamming codes without retransmission, which is a combination of hard and soft decision decoding, is proposed and its performance is analyzed in this paper. As results, hybsrid decision decoding shows a little bit higher residual bit error rate than soft decision decoding. However, as the size of the extended hamming code increases, the difference of th enumber of comparisons increases further. In addition, hybrid decision decoding shows almost same residual bit error rate as hard decision decoding with retrassmission and shows much lower residual bit error rate than hard decision decoding without retransmission.

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An Algorithm for Bit Error Rate Monitoring and Adaptive Decision Threshold Optimization Based on Pseudo-error Counting Scheme

  • Kim, Sung-Man
    • Journal of the Optical Society of Korea
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    • v.14 no.1
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    • pp.22-27
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    • 2010
  • Bit error rate (BER) monitoring is the ultimate goal of performance monitoring in all digital transmission systems as well as optical fiber transmission systems. To achieve this goal, optimization of the decision threshold must also be considered because BER is dependent on the level of decision threshold. In this paper, we analyze a pseudo-error counting scheme and propose an algorithm to achieve both BER monitoring and adaptive decision threshold optimization in optical fiber transmission systems. To verify the effectiveness of the proposed algorithm, we conduct computer simulations in both Gaussian and non-Gaussian distribution cases. According to the simulation results, BER and the optimum decision threshold can be estimated with the errors of < 20% and < 10 mV, respectively, within 0.1-s processing time in > 40-Gb/s transmission systems.

An Implementation of the NET-CUE System for Transmission of the Network Cuing Information (방송 정보 전송을 위한 NET-CUE 시스템의 설계 및 제작)

  • 전우성;박한규
    • Proceedings of the Korean Institute of Communication Sciences Conference
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    • 1987.04a
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    • pp.196-200
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    • 1987
  • In this paper A NET-CUE System is designed and implemented for tramsmission of the network cuing informations with using data packet broad casting techniques. This system is composed with encoder and decoder. To show the performance of this system An eye height and bit error rate are cheched. The eye height is greater than 74% and The bit error rate is less than 4.6 * 10 The exper imental results show that this system provides a good quality of the operation.

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Closed-form for Bit Error Rate of MSK and OQPSK Systems with a Smart Antenna

  • Le Minh-Tuan;Pham Van-Su;Yoon Giwan
    • Journal of information and communication convergence engineering
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    • v.3 no.4
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    • pp.176-178
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    • 2005
  • This paper presents closed-form expressions for exact bit error rate of MSK and OQPSK systems employing an adaptive antenna array at base station to eliminate co-channel interference. The channels under consideration are AWGN and one-path flat Rayleigh fading with AWGN. Computer simulation is carried out to confirm the theoretical results.

Cognitive Relay Networks with Underlay Spectrum Sharing and Channel Estimation Error: Interference Probability and BER Analysis

  • Ho-Van, Khuong
    • Journal of Communications and Networks
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    • v.16 no.3
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    • pp.301-304
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    • 2014
  • This paper proposes accurate interference probability and bit error rate formulas for cognitive relay networks with underlay spectrum sharing and channel estimation error (CEE). Numerous results reveal that the CEE not only degrades the performance of secondary systems (SSs) but also increases interference power caused by SSs to primary systems (PSs), eventually unfavorable to both systems. A solution to further protect PSs from this effect through reducing the power of secondary transmitters is investigated and analyzed.

Exact Bit Error Rate Analysis of Partial Relay Selection in Dual-Hop Decode-and-Forward Relaying Systems over Rayleigh Fading Channels (레일레이 페이딩 채널을 고려한 듀얼 홉 디코딩 후 전달 중계 시스템에서 부분 중계 노드 선택 기법의 정확한 비트 오차율 분석)

  • Lee, Sangjun;Lee, In-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.1
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    • pp.42-49
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    • 2014
  • The conventional best relay selection based on all the channel information for the first and second hops in dual-hop systems has a large consumption of resources for channel feedback. In this paper, we analyze the average bit error rate for partial relay selection based on the channel information only for the first hop in dual-hop decode-and-forward relaying systems, where we assume independent Rayleigh fading channels. In particular, we provide an exact and closed-form expression for the average bit error rate of M-ary QAM. Also, through numerical investigation, the performance of the partial relay selection is compared with the performance of the best relay selection, and the performance is evaluated for different numbers of relays and various average channel power ratios for the first and second hops.

Performance Evaluation of Convolution Coding OFDM Systems (컨볼루션 코딩 OFDM 시스템의 성능 분석)

  • Choi, Seung-Kuk
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.2
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    • pp.294-301
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    • 2013
  • OFDM technique uses multiple sub-carriers for the data transmission. Therefore, bit error rate increases because of inter-carrier interference caused by nonlinear high power amplifier and carrier frequency offset. Wireless OFDM transmission over multi path fading channels is characterized by small transmission gain in multiple sub-carrier frequency interval. Therefore bit error rate increases because of burst errors. Inter-leaver and convolution error control coding are effective for the reduction of this burst error. Pilot symbol is used for the channel estimation in OFDM systems. However, imperfect channel estimates in this systems degrade the performance. The performance of this convolution coding OFDM systems using inter-leaver, gauged by the bit error rate, is analyzed considering the nonlinear high power amplifier, carrier frequency offset and channel estimation error.

A Relay and Transmission Mode Selection Scheme to Enhance the Bit Error Rate Performance in Relay Systems (중계기 시스템에서 비트 오류율 성능 향상을 위한 중계기 선택 및 전송 모드 결정 방법)

  • Seo, Jong-Pil;Lee, Myung-Hoon;Lee, Yoon-Ju;Kwon, Dong-Seung;Chung, Jae-Hak
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.12A
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    • pp.941-949
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    • 2011
  • In a cooperative communication system with a source node and multiple relays equipping single antenna and a destination node equipping multiple antennas, the selective cooperative spatial multiplexing scheme can obtain spatial multiplexing gain and additional selection diversity gain. But it can degrade a bit error rate performance because some received symbols forwarded from particular relays may be lost by attenuation due to path-loss. We propose a relay and transmission mode selection scheme which selects minimum number of multiple relays having the channel capacity larger than a given data rate and transmission mode which switches spatial multiplexing and spatial diversity mode in cooperation phase to enhance the bit error rate performance. The proposed scheme achieves 1.5~2dB gain at the low SNR range compared with the conventional scheme by obtaining additional spatial diversity gain.

A study on weighting algorithm of multi-band transmission method using an estimated BER (추정 BER을 이용한 다중 밴드 전송 기법의 가중치 알고리즘 연구)

  • Shin, Ji-Eun;Jeong, Hyun-Woo;Jung, Ji-Won
    • The Journal of the Acoustical Society of Korea
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    • v.40 no.4
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    • pp.359-369
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    • 2021
  • In underwater communications, to compensate performance degradation induced from rapidly changing channel transfer characteristic, multi-band communication method which allocate the same data to different frequency bands is used. However, the multi-band configuration may have worse performance than the single-band one because performance degradation in a particular band affects the output from the entire bands. This problem can be solved through a receiving end that analyzes error rates of each band, sets threshold values and allocates lower weights to inferior bands. Therefore, this paper proposed a weighting algorithm based on estimated Bit Error Rate (BER) which analyzes reliability of received data based on the performance difference between demodulated and decoded data. Employing turbo codes with coding rate of 1/3, we evaluate the performance of the proposed weighted multi-band transmission model in real underwater environments based on optimal simulation parameters. Through the sea trial experiment, we confirmed error performance was improved by applying the proposed weighting algorithm.

Characteristics of Bit Error Rate dependence on the Position of Optical Phase Conjugator in 320 Gbps WDM System (320 Gbps WDM 전송 시스템에서 광 위상 공액기의 위치에 따른 비트 에러율 특성)

  • Lee Seong-Real
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.5
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    • pp.1123-1131
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    • 2005
  • In this paper, optimal position of optical phase conjugator (OPC) for best compensating distorted WDM channels due to both chromatic dispersion and self phase modulation (SPM) in $8{\times}40$ Gbps WDM systems is numerically investigated, and the eye opening penalty (EOP) and bit error rate (BER) characteristics of overall WDM channels at this position is investigated, comparing with that in case of OPC placed at mid-way of total transmission length. It is confirmed that the compensation extents in WDM system with OPC is more improved by the shifting OPC position from the mid-way of total transmission length, depending on the modulation format and fiber dispersion coefficient. Ant it is confirmed that, from a viewpoint of the reception performance, EOP of each channel is more or less different with one another, but the BER characteristics of overall channels are almost equal.