This article analyzes the characteristics of PON and WiMAX convergence network planning.Based on user coverage ratio,WiMAX channel allocation,cell radius,carrier-to-noise ratio threshold,and bandwidth constraint,we pr...This article analyzes the characteristics of PON and WiMAX convergence network planning.Based on user coverage ratio,WiMAX channel allocation,cell radius,carrier-to-noise ratio threshold,and bandwidth constraint,we propose a mixed integer programming model solved by a Branch-Band and Heuristic Search method.Finally,the simulation result is given and analyzed.The planning method based on a mixed integer programming model can save 20 percentage of the overall planning cost,compared with the greedy algorithm.The relationship between the convergence network planning cost and frequency usage is also analyzed.The optimized planning result with the lowest cost can be acquired through the best frequency usage.展开更多
In order to realize broadband and high-speed transmission in the last mile access network,the Coded Wavelength-Division Multiplexing(Coded-WDM)technique on PON(so-called CDM-PON)is presented on fiber-to-the-home acces...In order to realize broadband and high-speed transmission in the last mile access network,the Coded Wavelength-Division Multiplexing(Coded-WDM)technique on PON(so-called CDM-PON)is presented on fiber-to-the-home access network.In this paper,the codcd-WDM coder/decoder(codec}is configured on Optical Network Unit(ONU)and Optical Line Terminal(OLT)in Ethemet Passive Optical Network(E-PON).Here,network codecs are constructed with Arrayed Waveguide Grating(AWG)devices and the signature address code is employed as complementary Walsh code whose original code is for data bit'1'and complementary code is for data bit'0'respectively.It is shown that the simultaneous active user of proposed scheme using CWH code is improved 100%than using M-Sequence and conventional Walsh code for given bit error rate of 10^-9.In addition,the signal to noise ratio(SNR)performance is improved by 6dB compared with conventional scheme employed M-sequence and Walsh code.展开更多
Recently,the NGPON2 standards organization has decided to deploy LDPC code in upstream and downstream channels in next-generation Ethernet passive optical network(NG-EPON)systems.However,PON upstream channels operate ...Recently,the NGPON2 standards organization has decided to deploy LDPC code in upstream and downstream channels in next-generation Ethernet passive optical network(NG-EPON)systems.However,PON upstream channels operate in burst-mode,hence the turn-on effects in optical network units(ONUs)may introduce burst errors,which are difficult for LDPC to deal with.One of the solutions is introducing an interleaver to convert consecutive burst errors into separate random errors.The traditional interleavers such as the block interleaver and the random interleaver,only consider dispersing the consecutive errors.In this paper,we present a design methodology for channel-adaptive interleaving pattern by joint optimizing of interleaving and LDPC decoding in PON systems deploying LDPC codes.After determining the interleaving pattern where the bits can be recovered with more reliable messages during LDPC iterative decoding,we map the bits from the potential locations of burst errors to the interleaving positions.By doing so,we can not only disperse the burst errors but also make full use of the LDPC code to improve its decoding performance.The numerical results show that the proposed interleaving scheme has a better performance under any burst-error length.展开更多
基金supported by National High Technical Research and Development Program of China(863 program)under Grant No.2009AA01A345Fundamental Research Funds for the Central Universities under Grant No.BUPT2009RC0402
文摘This article analyzes the characteristics of PON and WiMAX convergence network planning.Based on user coverage ratio,WiMAX channel allocation,cell radius,carrier-to-noise ratio threshold,and bandwidth constraint,we propose a mixed integer programming model solved by a Branch-Band and Heuristic Search method.Finally,the simulation result is given and analyzed.The planning method based on a mixed integer programming model can save 20 percentage of the overall planning cost,compared with the greedy algorithm.The relationship between the convergence network planning cost and frequency usage is also analyzed.The optimized planning result with the lowest cost can be acquired through the best frequency usage.
文摘In order to realize broadband and high-speed transmission in the last mile access network,the Coded Wavelength-Division Multiplexing(Coded-WDM)technique on PON(so-called CDM-PON)is presented on fiber-to-the-home access network.In this paper,the codcd-WDM coder/decoder(codec}is configured on Optical Network Unit(ONU)and Optical Line Terminal(OLT)in Ethemet Passive Optical Network(E-PON).Here,network codecs are constructed with Arrayed Waveguide Grating(AWG)devices and the signature address code is employed as complementary Walsh code whose original code is for data bit'1'and complementary code is for data bit'0'respectively.It is shown that the simultaneous active user of proposed scheme using CWH code is improved 100%than using M-Sequence and conventional Walsh code for given bit error rate of 10^-9.In addition,the signal to noise ratio(SNR)performance is improved by 6dB compared with conventional scheme employed M-sequence and Walsh code.
基金supported by National Natural Science Foundation of China(No.U21A20454).
文摘Recently,the NGPON2 standards organization has decided to deploy LDPC code in upstream and downstream channels in next-generation Ethernet passive optical network(NG-EPON)systems.However,PON upstream channels operate in burst-mode,hence the turn-on effects in optical network units(ONUs)may introduce burst errors,which are difficult for LDPC to deal with.One of the solutions is introducing an interleaver to convert consecutive burst errors into separate random errors.The traditional interleavers such as the block interleaver and the random interleaver,only consider dispersing the consecutive errors.In this paper,we present a design methodology for channel-adaptive interleaving pattern by joint optimizing of interleaving and LDPC decoding in PON systems deploying LDPC codes.After determining the interleaving pattern where the bits can be recovered with more reliable messages during LDPC iterative decoding,we map the bits from the potential locations of burst errors to the interleaving positions.By doing so,we can not only disperse the burst errors but also make full use of the LDPC code to improve its decoding performance.The numerical results show that the proposed interleaving scheme has a better performance under any burst-error length.
