• Title/Summary/Keyword: multirate sampling

Search Result 36, Processing Time 0.021 seconds

A novel phase error predictor for servo system in home-use VCRs (가정용 VCR의 서보 시스템을 위한 새로운 위상 오차 예측기)

  • 이상락;박정배;유지윤;박귀태;신영후
    • The Transactions of the Korean Institute of Electrical Engineers
    • /
    • v.45 no.4
    • /
    • pp.530-534
    • /
    • 1996
  • A novel phase error predictor is proposed for servo system in home-use VCRs. The multirate system in VCRs is converted into a single period sampling system with faster sampling time by using the proposed novel phase error predictor. And the disturbances can be measured much faster. From the experimental results, we can see that the perfomance of the control system is improved greatly. The phase lock time of the proposed servo system is ten times faster than that of the conventional system.

  • PDF

A Novel Phase Error Predictor for VCR Servo Systems (VCR의 서보 시스템을 위한 새로운 위상 오차 예측기)

  • Lee, Sang-Lak;Park, Jung-Bae;Yoo, Ji-Yoon;Park, Gwi-Tae;Sheen, Yong-Hoo
    • Proceedings of the KIEE Conference
    • /
    • 1995.07a
    • /
    • pp.258-260
    • /
    • 1995
  • A novel phase error predictor is proposed for servo system in home-use VCRs. The multirate system in VCRs is converted into a single period sampling system with faster sampling time by using the proposed novel phase error predictor. And the disturbances can be measured much faster. From the experimental results, we can see that the performance of the control system is improved greatly. The phase lock time of the proposed servo system is ten times faster than that of the conventional system.

  • PDF

Intelligent Digital Redesign Via Complete State-Matching (완벽한 상태정합을 이용한 지능형 디지털 재설계)

  • Kim, Do-Wan;Joo, Young-Hoon;Park, Jin-Bae
    • Proceedings of the KIEE Conference
    • /
    • 2006.04a
    • /
    • pp.276-278
    • /
    • 2006
  • In this paper, a complete solution to fuzzy-model-based digital redesign problem (IDR) for sampled-data nonlinear systems is presented, The term of intelligent digital redesign (IDR) is to design a digital fuzzy controller such that the sampled-data closed-loop fuzzy system is equivalent to the continuous-time closed-loop fuzzy system using the state matching, Its solution is simply obtained by linear transformation, Under the proposed sampled-data controller, the states of the sampled-data and continuous-time fuzzy system are completely matched at every sampling points.

  • PDF

Performance Analysis of Blind Channel Estimation for Precoded Multiuser Systems

  • Xu, Zhengyuan
    • Journal of Communications and Networks
    • /
    • v.4 no.3
    • /
    • pp.189-198
    • /
    • 2002
  • Precoder has been shown to be able to provide source diversity and design flexibility. In this paper we employ precoding techniques for block transmission based on a multirate filterbank structure. To accommodate multiuser communication with variable data rates, different precoders with corresponding coefficients and up/down sampling rates are used. However, due to unknown multipath distortion, different interferences may exist in the received data, such as multiuser interference, intersymbol interference and interblock interference. To estimate channel parameters for a desired user, we employ all structured signature waveforms associated with different symbols of that user and apply subspace techniques. Therefore better performance of channel estimator can be achieved than the conventional subspace method based only on the signature of the current symbol. The delay for that user can also be jointly estimated. Channel identifiability conditions and asymptotic channel estimation error are investigated in detail. Numerical examples are provided to justify the proposed method. gest either multicode (MC) or multiple processing gain (MPG) mechanism [2], while requiring data rates to be integral multiples of some basic low-rate. In order to support variable rate transmission however, a comprehensive scheme needs to be investigated.

A Design of Two-stage Cascaded Polyphase FIR Filters for the Sample Rate Converter (표본화 속도 변환기용 2단 직렬형 다상 FIR 필터의 설계)

  • Baek Je-In;Kim Jin-Up
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.31 no.8C
    • /
    • pp.806-815
    • /
    • 2006
  • It is studied to design a low pass filter of the SRC(sample rate converter), which is used to change the sampling rate of digital signals such as in digital modulation and demodulation systems. The larger the conversion ratio of the sample rate becomes, the more signal processing is needed for the filter, which corresponds to the more complexity in circuit realization. Thus it is important to reduce the amount of signal processing for the case of high conversion ratio. In this paper it is presented a design method of a two-stage cascaded FIR filter, which proved to have reduced amount of signal processing in comparison with a conventional single-stage one. The reduction effect of signal processing turned out to be more noticeable for larger value of conversion ratio, for instance, giving down to 72% in complexity for the conversion ratio of 32. It has been shown that the reduction effect is dependent to specific combination of conversion ratios of the cascaded filters. So an exhaustive search has been performed in order to obtain the optimal combination for various values of the total conversion ratio. In this paper every filter is considered to be implemented in the form of a polyphase FIR filter, and its coefficients are determined by use of the Parks-McCllelan algorithm.

Linkage between Digital Down Converter System and Spectrum Sensing Method (Digital Down Converter 시스템과 스펙트럼 센싱 기법 연동 방안)

  • Hong, Moo-Hyun;Moon, Ki-Tak;Kim, Ju-Seok;Kim, Kyung-Seok
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.10 no.3
    • /
    • pp.43-50
    • /
    • 2010
  • DDC(Digital Down Converter) is a conversion technology to decimate to a lower sampling rate and DDC for the future development of communications technology has the necessary skills. So, it has been recognized in the wireless and the SDR(Software Defined Radio) system as essential components. In addition, research is underway on spectrum sensing for efficient communications environment due to the shortage of frequency resources. In this paper, the DDC systems were analyzed for CIC(Cascaded Integrator Comb) Filter, WDF(Wave Digital Filter), SRC(Sample Rate Conversion) each module. Moreover, we proposed a linkage effectively between DDC system and Spectrum Sensing for improve the efficiency of use of frequency by computer simulations. The simulation results of the DDC system was applied to the spectrum sensing capabilities. Also, performance and complexity of the results were derived and proposed system was the result of the check.