Abstract: The invention relates to a quantum cascade laser emitting a TM polarized optical mode with a wavelength between 3 and 15 ?m, including a gain medium and a main waveguide. The latter includes a coupling section in contact with the gain medium, comprising a DFB diffraction grating. The coupling section has a width greater than or equal to a minimum width from which an antisymmetric supermode propagating in a laser guiding structure comprising the gain medium and the main waveguide, has a confinement factor in an active region of the gain medium strictly greater than those of the optical modes likely to be guided by the guiding structure. The main waveguide includes a core based on atoms from column IV A of the periodic table of elements and a SiN or chalcogenide confinement sublayer.

Abstract: An Automatic Link Establishment (ALE) system incorporating Avalanche Relay (AR) is disclosed. The system includes a plurality of network nodes such as a calling node, one or more intermediate nodes, and a responding node. The calling node transmits a link establishment message to the responding node through one or more intermediate nodes. The message is transmitted via one or more transmitting and receiving channels. The one or more intermediate nodes relay the message to the responding node or one or more different intermediate nodes. The responding node receives the message and responds back to the calling node through the one or more intermediate nodes. The message may be transmitted via the same one or more channels used to receive the message.

Abstract: A notification system for sending a message to a receiving station via one or more repeater stations is disclosed. The repeater stations receive the message over a channel from a sending station. The distributed network immediately begins transmitting a signal coordinated with the message received where the message appears as multipath to a receiver or set of receivers. This asynchronous relay transmission start minimizes the time to incorporate additional transmitters and allows strong links to be discovered and employed without waiting for synchronized subslot transmission starts. In other operations, an asynchronous scanning operation may be included to provide a sufficient transmission time to account for network worst case net cycle times.