• Title/Summary/Keyword: bit error rate

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Improved Method of Characteristics for Two way Subscriber Transmission Systems

  • Phetsomphou, Douangsamone;Tsuchiya, Naosuke;Tanaka, Kimio
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.1355-1359
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    • 2004
  • The two way subscriber transmission systems have tendency to spread its carrier frequency bandwidth or information bit rate and average bit error rate according to popularization of high speed information through the digital communication system, transmission medium and the Internet. This fact is an important incentive to realize new systems. These two way subscriber transmission systems usually use same cable or same carrier frequency bandwidth for up stream channel and down stream channel. In the systems, the disturbances of noise, crosstalk or fading affect the characteristics. Specifically, these disturbances cause the decrease of information bit rate and degradation of transmission quality. This paper proposes the improved method of their degradations using the particular feature of two way subscriber transmission systems and it makes clear proposed method is effective by theoretically and some numerical examples.

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Fabrication of an externally modulated optical transmitter and transmission of 2.5Gbit/s signal over a 150 km long nondispersion-shifted fiber) (외부변조 방식의 광송신기 제작 2.5Gbit/s 신호의 150km 광섬유 전송)

  • 한정희;윤태열;이상수;이창희
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.32A no.11
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    • pp.86-93
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    • 1995
  • An optical transmitter was designed and implemented using a commercially available LiNbO$_{3}$ Mach-Zehnder modulator and the power amplifiers. We have adopted a new method to stabilize the bias voltage of the modulator using the second order harmonic component of the dithering signal. This technique has been applied successfully to the 2.5 Gbit/s external modulator for more than 6 hours without bit error rate degradaton. We demonstrated a repeaterless transmission of a 2.5 Gbit/s signal over 150 km nondispersion-shifted fiber using the transmitter. The receiver sensitivity was -34.5 dBm at 10$_{-10}$ bit error rate. No appreciable BER degradation due to fiber dispersion were observed after transmission.

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Performance of multilevel polarization shift keying system (다중레벨 편광편이키잉 시스템의 성능)

  • 강석근;노윤환;주언경
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.34S no.7
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    • pp.1-8
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    • 1997
  • In this paper, Stokes parameters which represent the states of polarization of transmitted light are determined by potential function, which is used to obtain signals points in a multidimensional Euclidean structure. And performance of multilevel polarization shift keying(POLSK) system using the obtained parameters is also represented and analyzed. As results, bit error rate of multilevel POLSK system using the potential function is shown to be lower than the conventional one using the distance matrix. And as number of levels increases, the number of photons per bit for bit error rate of 10$^{-9}$ is also increased linearly. The multilevel POLSK system, therefore, is an energy efficient modulation technque as compared with the convnetional ones.

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Performance of cellular CDMA systems using orthogonal spreading codes in rayleigh fading channels (레일레이 페이딩 채널에서 직교확산부호를 이용한 셀룰러 CDMA 시스팀의 성능)

  • 조현욱;조용석;박상규
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.35S no.2
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    • pp.22-30
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    • 1998
  • In this paper, we analyze CDMA systems using M-orthogonal spreading codes. We assume that each user one set of M-orthogonal spreading codes allocated randomaly. The effect of multiple access interference from the reference and adjacent cells is considered slowly frequency selective rayleigh fading channels. and the adjacent cells interference is considered toanalyze the system performance. We calculate bit error rate and the maximum number of users whoe can communicate simulaneously within a cell by suing Rake receiver. By comparing CDMA systemwhich transmits 1 bit/spreding code, our system shows bit error rate decreases as M increases under the same bandwidth and infromation rate.

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Implementation of a Smart Antenna System for Wide-Band CDMA WLL Channel (광대역 CDMA WLL용 스마트 안테나 시스템 구현)

  • 김미경;황현구;김종헌;박환석;김상태;최승원
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.12 no.6
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    • pp.912-918
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    • 2001
  • This paper presents a performance analysis of experimental observations of a uplink smart antenna system operating in a wide-band CDMA environment designed for a WLL (Wireless Local Loop) system. The numerical results shown in this paper have been obtained from practical experiments using commercially developed mobile terminals. The beam pattern provided by the weight vector and the resultant BER (Bit Error Rate) are observed in both indoor and outdoor signal environments. From the experimental observations, it is concluded that the proposed smart antenna system provides significant improvements in receiving both indoor and outdoor signal environments.

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A Study on the Channel Estimation for Terrestrial Cloud Transmission Systems (지상파 클라우드 방송 시스템에서 채널 추정에 대한 연구)

  • Kim, Jeongchang;Park, Sung Ik;Kim, Heung Mook
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2014.06a
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    • pp.173-175
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    • 2014
  • In this paper, we compare a bit error rate performance with channel estimation for terrestrial cloud transmission systems in order to provide an advanced research. Since terrestrial cloud transmission systems experience co-channel interference from one or more transmitters, they have to operate under negative signal-to-noise ratio.

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Performance of differential Space-time Block Coded MIMO System using Cyclic Delay Diversity

  • Kim, Yoon-Hyun;Yang, Jae-Soo;Kim, Jin-Young
    • 한국정보통신설비학회:학술대회논문집
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    • 2007.08a
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    • pp.41-45
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    • 2007
  • Multi-input multi-output (MIMO) system can increase data rate, capacity and bit error rate (BER) performance compare to traditional single antenna system. However MIMO technique is pointed out the problem that has high complexity to design receiver. So a recent trend of research on the MIMO system pays more attention to simplified implementation of receiver structure. In this paper, we propose differential space time block code (STBC) for MIMO system with cyclic delay diversity (CDD). This structure can provide a very close performance to that of the conventional diversity scheme with maximum likelihood (ML) detection without channel estimation block while the receiver structure is highly simplified. Bit error rate (BER) performance of the proposed system is simulated for an AWGN channel by theoretical and simulated approaches. The results of this paper can be applicable to the 4G mobile multimedia communication systems.

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Balanced Transmit Scheme in Decode-and-Forward Cooperative Relay Communication (Decode-and-Forward 협력 릴레이 통신에서의 Balanced 전송 기법)

  • Cho, Soo-Bum;Park, Sang-Kyu
    • Journal of Internet Computing and Services
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    • v.12 no.6
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    • pp.35-42
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    • 2011
  • Cooperative relay communication for wireless networks has been extensively studied due to its ability to mitigate fading effectively via spatial diversity. In this paper, we propose a balanced transmit scheme in cooperative relay communication with decode-and-forward DF) scheme. The proposed scheme selects the feedback bits to obtain the maximum cooperative diversity gain. The simulation results show that the proposed scheme improves the bit error rate BER) performance as compare with a conventional scheme.

Additional Data Transmission Scheme Using Multiple-Antennas with Backward Compatibility for Legacy ATSC Terrestrial DTV Receivers (ATSC 지상파 DTV 수신기와 역호환성을 갖는 다중 안테나 부가데이터 전송 방식)

  • Park, Sung Ik;Kim, Heung Mook;Kim, Jeongchang
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2011.11a
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    • pp.78-81
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    • 2011
  • In this paper, we propose an additional data transmission scheme using multiple-antennas with backward compatibility for legacy ATSC (Advanced Television Systems Committee) terrestrial DTV (digital television) receivers. The proposed scheme improves the data rate and bit error rate performance compared to the conventional single antenna transmission scheme for additional data. Also, the proposed scheme guarantees backward compatibility for legacy ATSC DTV receivers.

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Additional Data Transmission Scheme Using Multiple-Antennas with Backward Compatibility for Legacy ATSC Terrestrial DTV Receivers (ATSC 지상파 DTV 수신기와 역호환성을 갖는 다중 안테나 부가데이터 전송 방식)

  • Park, Sung Ik;Kim, Heung Mook;Kim, Jeongchang
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2011.11a
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    • pp.247-250
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    • 2011
  • In this paper, we propose an additional data transmission scheme using multiple-antennas with backward compatibility for legacy ATSC (Advanced Television Systems Committee) terrestrial DTV (digital television) receivers. The proposed scheme improves the data rate and bit error rate performance compared to the conventional single antenna transmission scheme for additional data. Also, the proposed scheme guarantees backward compatibility for legacy ATSC DTV receivers.

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