This paper proposes an advanced substation integrated protection communication system based on the latest development in power system.The integrated protection communication system within a substation comprises a numb...This paper proposes an advanced substation integrated protection communication system based on the latest development in power system.The integrated protection communication system within a substation comprises a number of major components such as the merging unit, communication network and integrated protection unit.The design and capability evaluation of the communication network based on IEC61850 are focused on.Results show that huge information from 4 merging units can be transmitted real-time via adopting 100 Mbit/s optical fiber in a substation,and the proposed communication network is able to achieve required performance.展开更多
Performance characterization of chaotic masking encoding and decoding is studied in synchronization injected semiconductor lasers under condition of injected-feedback. The modulation response function of chaotic maski...Performance characterization of chaotic masking encoding and decoding is studied in synchronization injected semiconductor lasers under condition of injected-feedback. The modulation response function of chaotic masking encoding and its response factor are theoretically deduced and analysed by small-signal analysis. It is numerically demonstrated that there are peak values between 1.52 GHz and 3.18 GHz when the injection coefficient is between 0.2 and 0.8. The chaotic synchronization error equation is theoretically deduced and its root is given by small- signal analysis under condition of chaotic masking encoding. The chaotic decoding formula is also theoretically demonstrated. There are the least dale values of synchronization errors between the modulation frequencies of 0.79GHz and 1.91 GHz when the injection coefficient is between 0.1 and 0.8 in numerical simulation. The numerical result is well consistent with the theoretical demonstration.展开更多
We propose a Bang-Bang control scheme that can synchronize master-slave chaotic systems. The chaotic systems considered here are structurally different from each other. Different from some control strategies reported ...We propose a Bang-Bang control scheme that can synchronize master-slave chaotic systems. The chaotic systems considered here are structurally different from each other. Different from some control strategies reported previously, the scheme proposed here can be taken as a general one that is independent of the chaotic system itself.展开更多
In underwater optical wireless communication(UOWC),a channel is characterized by abundant scattering/absorption effects and optical turbulence.Most previous studies on UOWC have been limited to scattering/absorption e...In underwater optical wireless communication(UOWC),a channel is characterized by abundant scattering/absorption effects and optical turbulence.Most previous studies on UOWC have been limited to scattering/absorption effects.However,experiments in the literature indicate that underwater optical turbulence(UOT)can cause severe degradation of UOWC performance.In this paper,we characterize an UOWC channel with both scattering/absorption and UOT taken into consideration,and a spatial diversity receiver scheme,say a singleinput–multiple-output(SIMO) scheme,based on a light-emitting-diode(LED) source and multiple detectors is proposed to mitigate deep fading.The Monte Carlo based statistical simulation method is introduced to evaluate the bit-error-rate performance of the system.It is shown that spatial diversity can effectively reduce channel fading and remarkably extend communication range.展开更多
A distributed turbo codes( DTC) scheme with log likelihood ratio( LLR)-based threshold at the relay for a two-hop relay networks is proposed. Different from traditional DTC schemes,the retransmission scheme at the...A distributed turbo codes( DTC) scheme with log likelihood ratio( LLR)-based threshold at the relay for a two-hop relay networks is proposed. Different from traditional DTC schemes,the retransmission scheme at the relay,where imperfect decoding occurs,is considered in the proposed scheme. By employing a LLR-based threshold at the relay in the proposed scheme,the reliability of decoder-LLRs can be measured. As a result,only reliable symbols will be forwarded to the destination and a maximum ratio combiner( MRC) is used to combine signals received from both the source and the relay. In order to obtain the optimal threshold at the relay,an equivalent model of decoderLLRs is investigated,so as to derive the expression of the bit error probability( BEP) of the proposed scheme under binary phase shift keying( BPSK) modulation. Simulation results demonstrate that the proposed scheme can effectively mitigate error propagation at the relay and also outperforms other existing methods.展开更多
基金National Natural Science Foundation of China(No.50677003).
文摘This paper proposes an advanced substation integrated protection communication system based on the latest development in power system.The integrated protection communication system within a substation comprises a number of major components such as the merging unit, communication network and integrated protection unit.The design and capability evaluation of the communication network based on IEC61850 are focused on.Results show that huge information from 4 merging units can be transmitted real-time via adopting 100 Mbit/s optical fiber in a substation,and the proposed communication network is able to achieve required performance.
文摘Performance characterization of chaotic masking encoding and decoding is studied in synchronization injected semiconductor lasers under condition of injected-feedback. The modulation response function of chaotic masking encoding and its response factor are theoretically deduced and analysed by small-signal analysis. It is numerically demonstrated that there are peak values between 1.52 GHz and 3.18 GHz when the injection coefficient is between 0.2 and 0.8. The chaotic synchronization error equation is theoretically deduced and its root is given by small- signal analysis under condition of chaotic masking encoding. The chaotic decoding formula is also theoretically demonstrated. There are the least dale values of synchronization errors between the modulation frequencies of 0.79GHz and 1.91 GHz when the injection coefficient is between 0.1 and 0.8 in numerical simulation. The numerical result is well consistent with the theoretical demonstration.
基金Supported by the National Nature Science Foundation of China under Grant No 10371136.
文摘We propose a Bang-Bang control scheme that can synchronize master-slave chaotic systems. The chaotic systems considered here are structurally different from each other. Different from some control strategies reported previously, the scheme proposed here can be taken as a general one that is independent of the chaotic system itself.
基金supported by the National Key Basic Research Program of China (Grant No.2013CB329201)the National Natural Science Foundation of China (Grant Nos.61171066 and 61471332)the State Key Laboratory of Robotics
文摘In underwater optical wireless communication(UOWC),a channel is characterized by abundant scattering/absorption effects and optical turbulence.Most previous studies on UOWC have been limited to scattering/absorption effects.However,experiments in the literature indicate that underwater optical turbulence(UOT)can cause severe degradation of UOWC performance.In this paper,we characterize an UOWC channel with both scattering/absorption and UOT taken into consideration,and a spatial diversity receiver scheme,say a singleinput–multiple-output(SIMO) scheme,based on a light-emitting-diode(LED) source and multiple detectors is proposed to mitigate deep fading.The Monte Carlo based statistical simulation method is introduced to evaluate the bit-error-rate performance of the system.It is shown that spatial diversity can effectively reduce channel fading and remarkably extend communication range.
文摘A distributed turbo codes( DTC) scheme with log likelihood ratio( LLR)-based threshold at the relay for a two-hop relay networks is proposed. Different from traditional DTC schemes,the retransmission scheme at the relay,where imperfect decoding occurs,is considered in the proposed scheme. By employing a LLR-based threshold at the relay in the proposed scheme,the reliability of decoder-LLRs can be measured. As a result,only reliable symbols will be forwarded to the destination and a maximum ratio combiner( MRC) is used to combine signals received from both the source and the relay. In order to obtain the optimal threshold at the relay,an equivalent model of decoderLLRs is investigated,so as to derive the expression of the bit error probability( BEP) of the proposed scheme under binary phase shift keying( BPSK) modulation. Simulation results demonstrate that the proposed scheme can effectively mitigate error propagation at the relay and also outperforms other existing methods.