Patent ID: 7672588

Claim:
An access node for optical transmission network, including a first connection point and a second connection point, a first access point and a second access point, and a coupling device providing bidirectional coupling between, respectively: the first connection point and the first access point, the second connection point and the second access point, and the first connection point and the second connection point, which coupling device comprises: a first band splitter and a second band splitter, each band splitter being provided with a first port, a second port and a third port and providing selective bidirectional coupling of optical signals between its first port and said second or third ports, according to whether those signals are carried by wavelengths belonging to a first or a second spectral band, a first coupler bidirectionally coupling the second port of the second band splitter, on the one hand, to the second port of the first band splitter via a first channel and, on the other hand, to said second access point via a second channel, so that the second access point forms an optical input and an optical output of the access node, a second coupler bidirectionally coupling the third port of the first band splitter, on the one hand, to the third port of the second band splitter via a first channel and, on the other hand, to said first access point via a second channel, so that the first access point forms an optical input and an optical output of the access node.