Abstract: A cable comprises a cable body (1) provided with a tubular cavity (2) for including a stack (4) having a number of fibre ribbons (5), and with a preferred bending plane (X-X), e.g. through two strength elements (3) located in the cable body on either side of the cavity (2). The cavity has a mainly rectangular cross section and is provided with a pair of opposite sidewalls (2.1, 2.2), at any rate substantially, parallel to the preferred bending plane (X-X). The stack also comprises a spacer (6), included in such a manner that the stack fills the tubular cavity with some play, and the pair of opposite sidewalls provide upper and lower bounds of the stack. The said sidewalls preferably have a slight transverse convexity. The cable may be manufactured complete. The cable may also be completed after prior empty installation of the cable body. The cable permits very high fibre densities and allows for upgrading.

Abstract: Optical stabilization system having a signal source (1) connected to a transmission line (2) and a noise source (3). The signal source (1) comprises a laser having a number of laser modes within a first wavelength band for generating an optical transmission signal (S). The noise source generates a narrow-band noise signal which is inserted into the transmission line via coupling means (5) and is injected into the laser of the signal source (1). The noise signal forces the laser to operate in a laser mode within the noise band. Via a power distributor (11), a portion of the noise signal can also be injected into a laser of a further signal source (9) for stabilization in a laser mode within the same noise band. Any signals outside the noise band are removed from the transmission signal by a narrow-band filter (8). The stabilization system is applied in passive optical networks for groupwise wavelength assignment to network terminals.