Gaurav Pandey

Performance analysis of long reach colorless wavelength division multiplexed-orthogonal frequency division multiplexing-passive optical network with broadcast capability

Abstract. A colorless wavelength division multiplexed-orthogonal frequency division multiplexing-passive optical network (WDM-OFDM-PON) is presented, which is capable of supporting symmetric 10 Gbps downlink direct detection (DD) OFDM unicast signal, broadcast signal, and uplink on–off keying (OOK) signal up to 60 km that includes both single mode and dispersion compensation fiber. At each optical network unit (ONU), DD has been used to receive downlink unicast and broadcast OFDM data. A delay interferometer (DI) has been used at a central office to achieve 10 Gbps uplink signal transmission over 60 km distance utilizing a reflective semiconductor optical amplifier (bandwidth=1.5  GHz) at the ONU because DI works as a vestigial sideband filter and an optical equalizer. Broadcast channel does not affect the system performance because it generates a limited interference of the order of 0.1 to 0.28 dB to downlink and uplink channels, and this interference is distributed to every ONU. For bit error rate of 10−9, the receiver sensitivity of −24, −23.1, and −20.14  dBm is achieved by simulating downlink OFDM unicast channels, OFDM broadcast channel, and uplink OOK unicast channels, respectively, for a symmetric data rate of 10 Gbps over 60 km.

Performance Analysis of Long-Reach Coherent Detection OFDM-PON Downstream Transmission Using m-QAM-Mapped OFDM Signal

Abstract In this paper, orthogonal frequency division multiplexing (OFDM)-passive optical network (PON) downstream transmission is demonstrated over different lengths of fiber at remote node (RN) for different m-QAM (quadrature amplitude modulation)-mapped OFDM signal (m=4, 16, 32 and 64) transmission from the central office (CO) for different data rates (10, 20 30 and 40 Gbps) using coherent detection at the user end or optical network unit (ONU). Investigation is performed with different number of subcarriers (32, 64, 128, 512 and 1,024), back-to-back optical signal-to-noise ratio (OSNR) along with transmitted and received constellation diagrams for m-QAM-mapped coherent OFDM downstream transmission at different speeds over different transmission distances. Received optical power is calculated for different bit error rates (BERs) at different speeds using m-QAM-mapped coherent detection OFDM downstream transmission. No dispersion compensation is utilized in between the fiber span. Simulation results suggest the different lengths and data rates that can be used for different m-QAM-mapped coherent detection OFDM downstream transmission, and the proposed system may be implemented in next-generation high-speed PONs (NG-PONs).

WDM PON enhanced capacity architecture for unicast, multicast and broadcast through efficient sideband carrier modulation

We propose a flexible architecture of WDM-PON in which unicast, multicast and broadcast data is transmitted based on a novel scheme of using sidebands as carrier. We here transmit one unicast data, one multicast data and two broadcast data transmission to each ONU. With the help of single frequency reflection capacity of FBG and cyclic wavelength distribution property of the AWG a unicast/multicast data and broadcast data is transmitted to each ONU. Simulation with 10 Gbps downstream channel, 10 Gbps broadcast channel and 2.5 Gbps upstream transmission is demonstrated with acceptable performance. In the proposed architecture DI is used to separate optical carrier and sideband carrier. Carrier reuse scheme is used and therefore the ONUs are colourless.

Long Reach Broadcast Capable WDM-OFDM-PON Using Direct Detection OFDM for Downstream and Upstream

Here we have proposed a novel architecture of colorless WDM OFDM-PON, capable of transmitting 10Gbps direct detection OFDM unicast data in downstream and upstream directions up to 60 km using RSOA having acceptable performance.