Transmissive Star Coupler Research Articles

Fused-fiber-based 3-dB mode insensitive power splitters for few-mode optical fiber networks

We propose a 3-dB mode insensitive power splitter (MIPS) capable of broadcasting and combining optical signals. It is fabricated with two identical few-mode fibers (FMFs) by a heating and pulling technique. The mode-dependent power transfer characteristic as a function of pulling length is investigated. For exploiting its application, we experimentally demonstrate both FMF-based transmissive and reflective star couplers consisting of multiple 3-dB mode insensitive power splitters, which perform broadcasting and routing signals in few-mode optical fiber networks such as mode-division multiplexing (MDM) local area networks using star topology. For experimental demonstration, optical on-off keying signals at 10 Gb/s carried on three spatial modes are successfully processed with open and clear eye diagrams. Measured bit error ratio results show reasonable power penalties. It is found that a reflective star coupler in MDM networks can reduce half of the total amount of required fibers comparing to that of a transmissive star coupler. This MIPS is more efficient, more reliable, more flexible, and more cost-effective for future expansion and application in few-mode optical fiber networks.

Doubling the Number of Users in a WDM Star Network

In this paper, a new scheme is proposed to double the number of users in a WDM star network. The technique is based on using a single fiber to connect each user to the central N x N star coupler, instead of two fibers per user in the conventional schemes. Therefore, a star network using an N x N transmissive star coupler as a central hub can support (2N - 4) users in the proposed scheme instead of N users in the conventional scheme. Only two optical amplifers and two wideband optical filters are required to implement the new scheme.

Hybrid transmissive optical star couplers with gain using fiber amplifiers

A hybrid transmissive star coupler incorporating fiber amplifiers for wavelength-division multiplexed/frequency-division multiplexed (WDM/FDM) networks is proposed. It is found that the total fiber length and conduit length required for this hybrid star coupler/network can be reduced tremendously compared with either the centralized or the distributed cases. Furthermore, this coupler is easier to construct and more cost-effective.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Distributed Transmissive Optical Star Couplers Using Erbium-Doped Fiber Amplifiers

Distributed Transmissive Optical Star Couplers Using Erbium-Doped Fiber Amplifiers

Secure data optical fibre multiple-access communication technique

The letter describes a novel secure data optical fibre multiple-access communication technique based on the special properties of new transmissive star couplers.

New transmissive star couplers for full duplex channels

The letter describes a new type of optical transmissive star coupler which allows full duplex operation to be achieved with half the transmission channels of conventional transmissive star networks.

A Portable Fiber Optic Local Area Network

A portable fiber optic local area network has been implemented for emergency command center communications. This network operates under a carrier sense multiple-access (CSMA) protocol and employs an architecture based on a unique active star node. The node consists of a transmissive optical star coupler and active electro-optical transceivers. Terminal-to-node or node-to-node links may be as long as 1 km. An architecture developed around this node design is capable of modular expansion to accommodate a large number (several hundread) of data subscribers. In addition to data services, this network can support broadcast video and integrated technical control.

Asymmetrical star coupler for optical fiber systems

A technique has been developed for fabricating M x N fiber couplers that use different core-size fibers to improve the interconnection efficiency of multiterminal optical fiber systems. Experimental results are described for a 2 x 8 transmissive asymmetrical star coupler using 125-microm core diam input fibers and 63-microm core diam output fibers. This construction procedure also has the important advantage of improving the fiber throughput uniformity of fused biconical taper multiport couplers.

Fibernet: Multimode Optical Fibers for Local Computer Networks

Local computer networks which communicate over copper conductors have been developed both to promote resource sharing and provide increased performance. Such networks typically operate at bandwidth-length ( Bw \circ L ) products up to a few MHz \circ km . In this paper we consider the use of fiber optics in such networks, and give a status report on a star-configured fiber optic network experiment called Fibernet which operates at a Bw \circ L product of \sim 100 MHz\circ km at a data rate of 150 Mbits/s and which in its final phases will connect up to 19 stations. We compare the merits and problems of linear, ring and several star configurations, and of active versus passive networks. The packet communication protocol is discussed and network efficiency is calculated as a function of the packet length, channel capacity and network propagation time. We describe the system performance of the present Fibernet experiment, which uses a 19-port transmissive star coupler, GaAIAs injection lasers and avalanche photodiodes, and incorporates bi-phase data encoding. Power distribution inhomogeneities, observed in the output of the transmissive star coupler's mixer rod, are explained geometric-optically.

Star couplers using fused biconically tapered multimode fibres

We report the fabrication and testing of 4-, 7-and 19-fibre fused biconical taper transmissive star couplers for use with single multimode fibres. Overall insertion losses on six couplers range from −1.3 dB to −2.6 dB. Losses are nearly independent of N, the number of fibres, but dispersion of the powers in the output fibres increases significantly with N.