Patent ID: 8412044
Filing Date: 2013-04-02
Classification: H04J

Abstract:
1. A passive optical fiber network system configured for bidirectional transmission of downstream and upstream digital data traffic between a plurality of data sources and a plurality of end user devices, the data traffic comprising data to be transmitted specifically to and from one or more of said end user devices, the system including: a plurality of said data sources appointed to be in communication with OLTs designatable by sequential numbers 1 to ‘N’; and a plurality of end user devices being appointed to be in communication with a plurality of ONUs, said ONUs being equal in number to said OLTs forming ‘N’ ordered pairs a predetermined one of said ONUs being appointed to be in communication with a predetermined one of said OLTs; and a media access control system present in each of the OLTs having a burst mode clock data recovery circuit to recover the timing needed for each of data transmission and configured to identify and maintain the integrity of both the upstream and downstream data associated with each of OLT, ONU, and end user device, and wherein: each OLT is configured: i. to be communicatively coupled to one or more of the data sources, from which downstream data for corresponding said end user devices is to be received and to which upstream data from said end user devices is to be transmitted; ii. to transmit said downstream data to the predetermined ONU from said OLT; iii. to receive said upstream stream data from said predetermined ONU; and iv. said OLT transmitting said downstream data at a downstream base wavelength “λ each ONU is configured: i. to be communicatively coupled to at least one of the end user devices, to which said downstream data is to be transmitted and from which said upstream data is to be received; ii. to receive said downstream data from the OLT in communication with said ONU; iii. to transmit said upstream stream data to said OLT; and iv. said ONU receiving said downstream data at said downstream base wavelength λ the improvement wherein the system further comprises: N OLT-side wavelength converters, each said converter being associated with a particular on of said OLTs and having an OLT port and a multiplexer port; N ONU-side wavelength converters, each said converter being associated with a particular one of said OLT-side wavelength converters and having an ONU port and a demultiplexer port; said bidirectional communication between OLT multiplexer port and ONU port being effected through a single optical fiber as a high Gbps rate upstream burst mode signal with a first bit valid verification to ascertain the integrity of a burst-mode data stream as well as a high Gbps continuous mode downstream signal corresponding to each of N OLT side devices and each of N ONU side devices; said single optical fiber additionally carrying an auxiliary channel operating at a low Gbps rate continuous mode signal monitoring the integrity of the optical fiber operating at a wavelength that is subject to attenuation; an OLT-side optical multiplexer having at least N branching ports and one common port; an ONU-side optical demultiplexer having at least ‘N’ branching ports and one common port; and wherein, for all values of “i” ranging from 1 to ‘N’: a unique intermediate downstream wavelength λ the “i-th” said OLT is connected for data communications via its OLT optical connection to the OLT port of the “i-th” said OLT-side wavelength converter; each of said ONUs is connected for data communications via its ONU optical connection to the ONU port of the ONU-side wavelength converter with which said ONU is associated; said multiplexer port of the “i-th” said OLT-side wavelength converter is communicatively coupled to the “i-th” said branching port of said OLT-side optical multiplexer; said demultiplexer port of the “i-th” said ONU-side wavelength converter is communicatively coupled to the “i-th” said branching port of said ONU-side optical demultiplexer; a multiplex optical fiber communicatively connects said common port of said OLT-side optical multiplexer and said common port of said ONU-side optical demultiplexer; the “i-th” said OLT-side wavelength converter is operable to convert light at wavelength λ the “i-th” said ONU-side wavelength converter is operable to convert light at wavelength λ said OLT-side optical multiplexer is operable to: i. receive through its “i-th” branching port downstream data at said intermediate downstream wavelength λ ii. receive from said multiplex optical fiber through its common port an upstream multiplexed data signal including light of any one or more of said intermediate upstream wavelengths and demultiplex said signal by sending substantially all of the light of wavelength λ said ONU-side optical demultiplexer is operable to: i. receive through its “i-th” branching port upstream data at said intermediate upstream wavelength λ ii. receive from said multiplex optical fiber through its common port said multiplexed downstream data signal including light of any or all of said intermediate downstream wavelengths and demultiplex said signal by sending substantially all of the light of wavelength λ