Optical node

Abstract

An optical node (100) is disclosed. The optical node (100) comprises first and second line ports (104, 106) for Wavelength Division Multiplexing (WDM) signals and first and second pluralities of local add / drop ports (108, 110) for optical signals. The optical node further comprises a wavelength selective switch (112), coupled between the first and second line ports (104, 106) and configured to drop optical signals from a WDM signal traversing the optical node between the first and second line ports (104, 106), and a node optical combiner (114) coupled between the first and second line ports (104, 106) and configured to add optical signals to a WDM signal traversing the optical node between the first and second line ports (104, 106). The optical node also comprises first and second switching units (116, 118), each switching unit coupled to the wavelength selective switch(112), the node optical combiner (114), a respective one of the first and second pluralities of local add / drop ports (108, 110) and the other of the first and second switching units (116, 118). Each of the first and second switching units (116, 118) is configured to distribute dropped optical signals from the wavelength selective switch (112) to its coupled plurality of local add / drop ports and to provide optical signals from its coupled plurality of local add / drop ports to the node optical combiner (114). Each of the first and second switching units (116, 118) is also configured to distribute optical signals from its coupled plurality of local add / drop ports to the other of the first and second switching units (116, 118) and to distribute optical signals from the other of the first and second switching units to its coupled plurality of local add / drop ports.

Description

technical field [0001] The present invention relates to optical nodes and in particular but not exclusively to optical nodes which may form part of a fronthaul network connecting radio equipment and radio equipment controllers in a communication network. Background technique [0002] In a cellular communication network, a radio base station (RBS) provides radio network coverage within a coverage area or cell. In some implementations, a radio base station may be partitioned into one or more radio units and one or more baseband processing units, enabling optimization of radio unit placement, among other advantages. A radio unit may be referred to as a remote radio unit (RRU) or radio equipment (RE). The baseband processing unit may be referred to as a digital unit (DU), baseband unit (BBU) or radio equipment controller (REC). The Common Public Radio Interface (CPRI) specifies the internal interface protocol for RBS communication between REs and RECs. [0003] The increasing...

AI Technical Summary

Problems solved by technology

However, the devices in the hub node are not transparent in terms of bitrate or protocol

This lack of transparency means that future network evolutions made possible by the development of new transport and interface protocols may require hardware replacement or reconfiguration in the fronthaul network

Additionally, the additional power requirements for OEO switching and CPRI switching increase the operating costs of such existing optical networking solutions

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