Optical line terminal for a passive optical wavelength division multiplex network

Patent metadata

Field	Value
Publication number	US-2016197697-A1
Application number	US-201414916615-A
Country	US
Kind code	A1
Filing date	Sep 19, 2014
Priority date	Sep 30, 2013
Publication date	Jul 7, 2016
Grant date	—

Abstract

Proposed is an OLT for a passive optical wavelength division multiplex network. The network contains optical transmitters for generating downstream signals of an L-Band, as well as optical receivers for receiving upstream signals of a C-Band. Furthermore, the OLT contains a bi-directional SOA and an optical interface. The optical interface, the SOA, the transmitters and the receivers are optically coupled such that an upstream signal received at the optical interface is firstly provided to the bi-directional SOA and subsequently from the SOA to one of the receivers, and such that a downstream signal generated by one of the transmitters is firstly provided to the bi-directional SOA and then subsequently to the optical interface. The bi-directional SOA has a gain function that is not constant with respect to a wavelength of an optical signal to be amplified. Furthermore, the gain function is maximal for a wavelength located within the C-band.

First claim

1 ) Optical Line Terminal for a passive optical wavelength division multiplex network, comprising,
multiple optical transmitters operable to generate respective downstream signals having respective different downstream wavelengths that are located in the L-Band, multiple optical receivers operable to receive respective upstream signals having respective different upstream wavelengths that are at least partially located in the C-Band, a bi-directional optical amplifier an optical interface,
wherein said optical interface, said bi-directional optical amplifier, said transmitters and said receivers are optically coupled such that
an upstream signal received at said optical interface is firstly provided to said bi-directional optical amplifier and subsequently from said bi-directional optical amplifier to one of said receivers, and such that
a downstream signal generated by one of said transmitters is firstly provided to said bi-directional optical amplifier and then subsequently to said optical interface,

wherein the coupling is given by one or more optical filtering devices,
and wherein said bi-directional optical amplifier has a wavelength dependent gain function that is not constant and wherein said gain function has a maximal gain value for a wavelength located within said C-band,
and wherein said gain function has a decreased gain value for a wavelength located within said L-band.

2 ) Optical Line Terminal according to claim 1 ,
wherein said amplifier is a semiconductor optical amplifier.

3 ) Optical Line Terminal according to claim 1 ,
wherein said passive optical wavelength division multiplex network is a passive optical time wavelength division multiplex network.

4 ) Optical Line Terminal according to claim 3 ,
wherein said passive optical wavelength division multiplex network is a passive optical time wavelength division multiplex network of the type NG-PON2.

5 ) Optical Line Terminal according to claim 1 ,
wherein said downstream wavelengths are located within a downstream band with a wavelength range of 1596-1603 nm.

6 ) Optical Line Terminal according to claim 1 ,
wherein the bandwidth of said downstream band is 7 nm.

7 ) Optical Line Terminal according to claim 1 ,
wherein a wavelength separation of different downstream signals is given by a wavelength difference of maximally 7 nm.

8 ) Optical Line Terminal according to claim 1 ,
wherein said upstream wavelengths are located in a upstream wavelength range of 1524-1544 nm.

9 ) Optical Line Terminal according to claim 1 ,
wherein the bandwidth of said upstream band is 20 nm.

10 ) Optical Line Terminal according to claim 1 ,
wherein said upstream band and downstream band are separated by at least 50 nm.

11 ) Optical Line Terminal according to claim 1 ,
wherein a lowest upstream wavelength is separated from a highest downstream wavelength by maximally 80 nm.

Assignees

• Alcatel Lucent

Inventors

• Bonk Rene
• Schmuck Harald
• Poehlmann Wolfgang

Classifications

• H04Q11/0067

  Provisions for optical access or distribution networks, e.g. Gigabit Ethernet Passive Optical Network (GE-PON), ATM-based Passive Optical Network (A-PON), PON-Ring · CPC title

• H04J14/08

  Time-division multiplex systems · CPC title

• H04J14/0205

  Select and combine arrangements, e.g. with an optical combiner at the output after adding or dropping · CPC title

• H04J14/0282

  WDM tree architectures · CPC title

• H04B10/2972

  Each direction being amplified separately · CPC title