Abstract:
The location and type of equipment shelf installed in an optical fiber distribution frame is detected and transmitted to a software management system automatically. A plurality of photo transceivers, arrayed on the frame, detects encoded indicia on each shelf. The coded information is inventoried into a database and displayed in a virtual graphical representation of the frame.

Description:
FIELD OF THE INVENTION 
     This invention relates to the field of telecommunications, and more particularly to a system to automatically detect the placement and nature of equipment shelves within an optical fiber distribution frame. 
     BACKGROUND OF THE INVENTION 
     Many telecommunications applications utilize an optical fiber network of interconnected optical fiber cables to enable optical communications between network locations. Ordinarily, a unique fiber routing will be required to transmit light pulses between network locations. Over this unique route, light pulses may be propagated across several different fibers. At each transition from one fiber to another, individual fibers are connected, thereby enabling light pulses to be carried between a first fiber and a second fiber. In many cases, such as at a central office for the communications system, large numbers of fiber connections must be made and a fiber administration system is employed to manage the various connections. 
     In many fiber administration systems, as the optical fibers in a network enter the central office, they are directed into an optical fiber distribution frame (FDF) where the individual optical fibers are terminated in an organized manner. Such fiber administration systems are exemplified by the LGX® fiber administration system that is currently manufactured by Lucent Technologies of Murray Hill, N.J., the assignee herein. 
     The FDF accommodates the placement and management of optical jumpers for interconnecting or cross connecting optical transmission equipment and outside plant (OSP) fibers. The FDF typically includes an upright structural framework or support member having a space or bay within the support member to hold racks or shelves of terminal equipment. Such shelves will be of varying sizes (height) and the terminal equipment will be directed to various functions. 
     In many cases, OSP is now managed by the fiber administration system with a software management system. The system is configured to provide a graphical representation of the shelves on the FDF, using a graphical user interface (GUI) with a computer (controller). The graphical representation shows what kinds of shelves are installed, where in the FDF each shelf is placed, and the specifications of each shelf. The specifications of the shelves include, but are not limited to, what fiber terminates at what location, what kinds of connectors are used, and an identification of a user/carrier for a given fiber. 
     In the current art, data from which the controller and the GUI determine and provide virtual images of the shelves are manually added to the system by the user, typically based upon feedback from the service technician who installed the equipment. It is possible to provide the virtual placement, or functional identity, for the shelf incorrectly. In that event, the graphical representation of the FDF would not accurately display the actual shelf placement in the field. Furthermore, there is often a time lag between the installation of the shelves and the updating of the graphical representation. 
     Accordingly, there is a need to provide a shelf detection system that will automatically detect the placement and nature of equipment shelves within an optical fiber distribution frame. 
     There is a further need to provide a shelf detection system of the type described and that will synchronize the virtual representation with the actual placement of the shelf within the FDF. 
     There is a still further need to provide a shelf detection system of the type described and that does not require shutting down and restarting of the computer system every time a shelf is added, thus enabling a “plug and play” procedure. 
     There is a yet further need to provide a shelf detection system of the type described and that is simple, reliable, and accurate. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention, there is provided a shelf detection system for a fiber distribution frame, for use in connection with a controller. The shelf detection system comprises an upright support member extending between upper and lower ends, and at least one shelf releasably mounted on the upright support member at a selected location. 
     In an illustrative embodiment, a plurality of photo transceivers are spaced apart uniformly along the upright support member. The photo transceivers are connected to the controller. An optically reflective surface is disposed on the shelf. The optically reflective surface is in optical alignment with one of the photo transceivers when the shelf is mounted on the upright support member. Thus, the shelf location will be transmitted to the controller. 
     The optically reflective surface further comprises encoded indicia detectable by the photo transceivers. The encoded indicia include encoded specifications of the shelf upon which the optically reflective surface is disposed. Upon mounting the shelf on the upright support member, one or more of the photo transceivers will detect the shelf and transmit the specifications of the shelf to the controller. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     A more complete understanding of the present invention may be obtained from consideration of the following description in conjunction with the drawing, in which: 
     FIG. 1 is a front elevational view of an optical fiber distribution frame with several equipment shelves in place; 
     FIG. 2 is a side elevational partially cut-away view of the optical fiber distribution frame of FIG. 1, taken along lines  2 — 2  of FIG. 1, and showing an equipment shelf and a shelf detection system constructed in accordance with the invention; and 
     FIG. 3 is an isometric view of the equipment shelf of FIG. 2, taken along lines  3 — 3  of FIG.  2 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings, and especially to FIG. 1, a fiber distribution frame  10  has an upright support member  12  extending between upper  14  and lower  16  ends. At least one equipment shelf  18 , and typically several shelves  18 , are releasably mounted on the upright support member  10  at selected locations. 
     Turning now to FIG. 2 as well as FIG. 1, a plurality of detectors  20  are spaced apart uniformly along the upright support member  12 . For an illustrative embodiment of the invention, the detectors  20  will be implemented as photo transceivers, and the remainder of the discussion of FIG. 2 will be focused on the use of such photo transceivers. However, it should be understood that the function of the detectors can be realized in a variety of implementations are, including pressure sensitive transducers, resisted transducers, push-button activated switches, making electrically coded contacts and bar-code detection systems. These and similar detection arrangements which will be apparent to those skilled in the art of the invention are intended to be within the scope of the disclosed and claimed invention. 
     The photo transceiver detectors  20  can be of any type, and typically include light-emitting diode transceivers, infrared light transceivers, and laser transceivers. The photo transceivers  20  are connected to the controller (not shown) by conductors  22 . 
     Referring now to FIG. 3, as well as FIGS. 1 and 2, an optically reflective surface  24  is disposed on the shelf  18 . (It should be understood that optically reflective surface  24  is associated with the photo transceiver implementation of this illustrative embodiment, and that other manifestations of the detector function of the invention might involve other media disposed on the shelf for communication with the detector.) The optically reflective surface  24  is in optical alignment with one of the photo transceivers  20  when the shelf  18  is mounted on the upright support member  10 . The optically reflective surface  24  may also incorporate encoded indicia  26  detectable by the photo transceivers  20 . Such encoded indicia  26  may include encoded specifications of the shelf  18  upon which the optically reflective surface  24  is disposed. The encoded indicia  26  may be in the form of a bar code, or any optically readable code. Thus, upon mounting the shelf  18  on the upright support member  10 , one of the photo transceivers  20  will detect the shelf  18  and transmit the location and specifications of the shelf  18  to the controller. 
     According to the invention, a method is disclosed for shelf detection in a fiber distribution frame. The method is for use in connection with a controller, as described above. The method comprises the steps of; extending an upright support member  10  between upper  14  and lower  16  ends; mounting at least one shelf  18  releasably in a selected location on the upright support member  10 ; mounting a plurality of detectors  20  on the upright support member  10 ; spacing the detectors  20  apart, preferably uniformly, along the upright support member  10 ; connecting the detectors  20  to the controller; mounting a detectable medium  24  on the shelf  18 ; aligning the detectable medium  24  so as to being communication with one of the detectors  20  when the shelf  18  is mounted on the upright support member  10 ; detecting the shelf  18  location with the detector  20 ; and transmitting the shelf  18  location from the detector  20  to the controller. 
     In a further embodiment, the method of the invention includes the incorporation of encoded indicia  26  with the detectable medium  24 ; providing, within the encoded indicia  26 , encoded specifications of the shelf  18  upon which the detectable medium  24  is disposed; detecting the encoded indicia  26  by the detector  20 ; and transmitting the specifications of the shelf from the detector  20  to the controller. 
     In a still further embodiment, the method of the invention includes providing a bar code as the encoded indicia. 
     For a yet further embodiment, the method of the invention includes providing light-emitting diode transceivers, infrared light transceivers, or laser transceivers as the detectors. 
     Numerous modifications and alternative embodiments of the invention will be apparent to those skilled in the art in view of the foregoing description. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the best mode of carrying out the invention. Details of the structure may be varied substantially without departing from the spirit of the invention and the exclusive use of all modifications which will come within the scope of the appended claims is reserved.