Applications Of Orthogonal Modulation And Line Coding In PON Evolution And Remodulation

After many years of development, the speed of backbone network is very high now, so low speed access network becomes the bottle neck of the network bandwidth. Nowdays, passive optical network (PON), one kind of network optical access network, becomes the most attractive access solution. According to the different multiplexing method, passive optical network can be divided into several categories:time division multiplexing passive optical network (TDM PON), wavelength division multiplexing passive optical network (WDM PON), code division multiplexing passive optical network (OCDMA PON), subcarrier multiplexing passive optical network (SCM PON) and orthogonal frequency division multiplexing passive optical network (OFDM PON), etc. TDM PON and WDM PON are the main PONs.PON evolution, remodulated WDM PON and the broadcast/multicast in remodulated WDM PON are some research hotspots in PON domain. In this paper, we propose the application of linecoding and orthogonal modulation in PON evolution, and demonstrate and test the proposed scheme by software simulation and experiment test.Some modulations such as differential phase shift keying (DPSK), polarization shift keying and frequency shift keying don’t change the amplitude of the optical carrier, so they can be considered as orthogonal to amplitude modulation, also orthogonal modulation called. Based on this, in this paper we propose PON evolution scheme based on orthogonal modulation. The new PON signal is orthogonal modulated, avoid the effection on old PON signal. We set up the experimental setups of evolution schemes basd on DPSK and PolSK, achieving20kilometer and25kilometer transmission respectively.Linecoding can use some special line code to decrease the low-frequecy component of coded signal. In this paper, we propose to linecode high speed new PON signal in PON evolution and downstream signal asymmetric remodulated PON, to decrease the crosstalk to low speed old PON signal and upstream signal. By changing the linecodes with different code efficiency, the crosstalk induced by new PON signal and downstream signal to old PON signal and upstream signal is minimized in different evolution stages and under different downstream bandwidth demands. The selection of linecodes and the advantages and disadvantages of linecode application are also discussed in this paper.At the last of this paper, we propose the application of linecoding and orthogonal modulation in broadcast/multicast enabled remodulated WDM PON. We use the combination of IRZ-Manchester code and DPSK and the combination of Inverse PPM and PolSK to achieve broadcast/multicast enabled remodulated WDM PON respectively. In this paper, we detailedly introduce the proposed IRZ-Manchester code and Inverse PPM. Then we test the applicaiton performance of these two codes in proposed schemes by simulation software and experimental setup, and make the comparsion with the performance of IRZ code and Manchester code. According to the results, the proposed IRZ-Manchester code and Inverse PPM show better performance. At lase, we make comparison between IRZ-Manchester code and Inverse PPM, discussing the advantages, disadvantages and application scope of them...