WO2014009466A2

WO2014009466A2 - Presence detection using leds in rfid physical layer management system

Info

Publication number: WO2014009466A2
Application number: PCT/EP2013/064673
Authority: WO
Inventors: Ian Miles Standish; Kristof Vastmans; Kristof Johan JEURIS
Original assignee: Tyco Electronics Raychem BVBA; Tyco Electronics UK Ltd
Current assignee: Commscope Connectivity Belgium BVBA; Tyco Electronics UK Ltd
Priority date: 2012-07-11
Filing date: 2013-07-11
Publication date: 2014-01-16
Anticipated expiration: 2015-01-11
Also published as: WO2014009466A3

Description

PRESENCE DETECTION USING LEDS IN RFID PHYSICAL LAYER MANAGEMENT SYSTEM

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of United States Provisional Patent

Application Serial No. 61/670,365, filed on July 11, 2012, which is hereby incorporated herein by reference.

BACKGROUND

[0002] Patching systems are commonly used in communication networks in order to provide flexibility in implementing communication links. Examples of patching systems include patch panels used with optical or copper patch cords and optical distribution frames used with optical patch cords. Such patching systems typically house a plurality of ports. Each port is associated with a first (or front) connector and a second (or rear) connector (or other attachment mechanism such as a punch-down block or

permanently attached optical fiber). Each port is configured to communicatively couple any cable attached to the front connector of that port to any cable that is attached to the rear of that port. Other patching systems are implemented in similar ways.

[0003] Many types of physical layer management (PLM) systems have been developed in order to keep track of which cables are attached to which ports of a patching system. In one type of system, each connector that is attached to a front connector of a patch panel has a radio frequency identification (RFID) tag attached to it. An RFID reader can then be used to wirelessly read an identifier and other information from each connector's RFID tag in order to keep track of what connectors and cables are attached to the front connectors of the patch system.

[0004] However, if a connector that does not include an RFID tag is inserted into the front of a port, the RFID reader itself will not be able to detect that fact since there will be no response when the RFID reader attempts to read any RFID tag near that port. A connector that does not include an RFID tag is also referred to here as a "foreign" connector. From the perspective of the RFID reader, this situation (where a foreign connector is inserted into the front of a port) is indistinguishable from a situation where no connector is inserted into the front the port.

[0005] To detect such foreign connectors, conventional RFID PLM systems typically include a sensor mechanism for each port to detect the presence of any connector being inserted into that port. In one example, an infrared (IR) sensor mechanism is used that produces an IF beam that is broken by any connector that is attached to a port. However, this approach makes use of a separate IR emitter/detector pair for each port in the patching system, which increases the cost and complexity of using such an approach.

[0006] Another approach to detecting a foreign connector in a port makes use of a switch (or similar mechanism) that is actuated when the foreign connector is inserted into the front of the associated port. With such an approach, the switch is configured so that any connector that is inserted into the associated portion will come into physical contact with the switch in order to actuate the switch. However, these contact switch sensors are more susceptible to failure than non-contact approaches. Also, such contact-switch sensor approaches are often not suitable for use in the outside plant of a telecommunication service provider's network, where the ports can be exposed to dirt and other conditions that can cause such contact-switches to fail sooner.

SUMMARY

[0007] One embodiment is directed to an apparatus (such as a patching system or other communication device) that comprises a plurality of ports and a plurality of light emitting diodes. Each port has a respective associated pair of light emitting diodes positioned near the port so that a line of sight can be established between the pair if no connector is attached to that port and so that the line of sight will be broken if a connector is attached to that port. For each pair, a first light emitting diode is operated as an emitter that emits light, a second light emitting diode is operated as a detector to detect the light emitted from the first one of the light emitting diodes, and the apparatus is configured to determine if a connector is attached to the associated port associated based on information generated by the second light emitting diode.

[0008] Other embodiments are also disclosed.

DRAWINGS

[0009] FIG. 1 is a block diagram illustrating one exemplary embodiment of a patching system in which the presence detection techniques described here can be used.

[0010] FIG. 2 is a flow diagram of one exemplary method of detecting the presence of a connector.

DETAILED DESCRIPTION

[0011] FIG. 1 is a block diagram illustrating one exemplary embodiment of a communication device 100 in which the presence detection techniques described here can be used. In this example, the communication device 100 is implemented as a patching system (though it is to be understood that the presence detection techniques described here can be used with other types of communication devices).

[0012] More specifically, in the exemplary embodiment shown in FIG. 1, the patching system is implemented in an optical connector tray 100 that can be used in an optical distribution frame (not shown). Typically, an optical distribution frame comprises one or more racks in which one or more subracks are mounted. Each subrack comprises an enclosure and a shelf. Each subrack is configured so that each shelf can slide in and out of an opening formed in the front of the enclosure. The tray 100 shown in FIG. 1 can be used in such an optical distribution frame. However, it is to be understood that the presence detection techniques described here can be used in other PLM systems and as a part of other types of systems and devices. [0013] The tray 100 shown in FIG. 1 comprises a set of ports 102. Each port 102, in the exemplary embodiment shown in FIG. 1, is implemented using an adapter 104 that is configured to hold two optical connectors 106 and 108 (only one of each is shown in FIG. 1) in place while the fibers 110 and 112 terminated by those connectors 106 and 108, respectively, are optically coupled to one another. In the exemplary embodiment shown in FIG. 1, each connector 106 and 108 terminates a single fiber 110 and 112, respectively; however, in other embodiments, each connector 106 and 108 can terminate multiple fibers.

[0014] Examples of fiber optic adapters 104 and connectors 106 and 108 that can be used include SC, LC, FC, LX.5, MTP, or M PO adapters and connectors. Other adapters and connectors can also be used.

[0015] In the example shown in FIG. 1, each adapter 104 comprises two sides 114 and 116, where one connector 106 is connected to a first side 114 of the adapter 104 and where the other connector 108 is connected to the other side 116 of the adapter 104.

[0016] In this example, the fiber optic adapters 104 are arranged and held on the tray 100 so that first side 114 of all of the adapters 104 face the same direction and are aligned with one another. In this example, each adapter 104 is held on the tray 100 by a plastic clip 118. This allows each fiber optic adapter 104 to be easily removed and attached to the tray 100 by a technician when inserting or removing a connector from the adapter 104.

[0017] In this example, the tray 100 is configured to have one side 114 of the adapters 104 serve as the "patch field" or "patch side". The patch side is the side where the optical patching is performed using patch cords 120. The tray 100 is configured to have the other side 116 of the adapters 104 serve as the "fixed side", where fixed optical cabling 122 is attached. Typically, connectors 106 attached to one end of optical patch cords 120 are attached to the patch side 114 of an adapter 104. The patch cords 120 exit that tray 100, and the other end of the patch cord 120 is typically connected to the patch side of another adapter or another device in the network.

[0018] Connectors 108 attached to one end of fixed optical cabling 122 can be attached to the fixed side 116 of an adapter 104. The fixed optical cabling 122 can be an optical pigtail, in which case the other end of the pigtail comprises a fiber that is spliced (for example, using a smooth) to another longer optical fiber that exits the tray 100. The other end of the longer cable is connected as appropriate (for example, at another optical node located somewhere else in the network). The fixed optical cables 122 that are connected to the fixed side 116 of the adapters 106 can themselves exit the tray 100 (like the patch cords 120 attached to the patch side 114 of the adapters 104) and can be connected as appropriate (for example, at another optical node located somewhere else in the network).

[0019] In this example, the connectors 106 attached to the patch side 114 of the adapters 104 have RFID tags 107 attached to them or integrated into them. The RFID tags 107 store a unique identifier for the connector 106 and/or the patch cord 120 that can be used to identify which patch cord 120 is attached to each adapter 104. The RFI D tags 107 can store other information. Also, information can be written to the RFID tags 107, and information can be read from the RFID tags 107.

[0020] Each tray 100 comprises a printed circuit board 126. As shown in FIG. 1, the tray PCB 126 includes a respective RFID antenna or coil 128 and respective "visible" LED (or other visual indicator) 130 positioned near the patch side 114 of each fiber optic adapter 104.

[0021] Each RFID antenna or coil 128 is used for reading an RFID tag 107 associated with any connector 106 inserted into the respective adapter 104. In this example, a single RFI D reader 132 can be selectively coupled to the RFI D antenna or coil 128 near the front side 114 of each adapter 104 using one or more multiplexers 134. In this way, only one RFID reader 132 is needed to read RFID tags 107 associated with each of the fiber optic adapters 104 held on the tray 102. For simplicity of illustration, only the connection between one RFID antenna 128 and multiplexer 134 is shown in FIG. 1, though it is to be understood that all of the RFID antennas 128 are connected to the multiplexer 134. Also, in FIG. 1, the connector 106 that is shown as being connected to a port 104 covers the corresponding RFID antenna 128 such that it is not visible in FIG. 1.

[0022] Each visible LED or other visual indicator 130 is used for visually identifying the respective adapter 104 (for example, in connection with guiding a technician in carrying out a work order). As used herein, "visible" refers to the fact that the LED 130 (and the light emitted from it) can be viewed by a user.

[0023] At least one controller 136 is associated with the tray 102 and is used to control the reading of RFID tags 107 and the illumination of the visible LEDs 130.

[0024] The controller 136 is configured to cause the RFID reader 132 to read any RFID tag 107 that is attached to any connector 106 inserted into the patch side 114 of one adapter 104. The controller 136 causes each adapter 104 to be "read" by using the multiplexer 134 to couple the RFID reader 132 to the RFID antenna 128 associated with that adapter 104. The controller 136 can read the adapters 104 in a polling manner, where the controller 136 periodically causes each such adapter 104 to be read. This can also be done in an event-driven manner where the controller 136 causes the RFID reader 132 to attempt to read any RFID tag 107 attached to a connector 106 that has been recently inserted into the patch side 114 of an adapter 104. In order to do this, the controller 136 needs to know when a connector 106 has been inserted into the patch side 114 of an adapter 104.

[0025] In the embodiment shown in FIG. 1, the tray PCB 126 comprises a plurality of "detection" LEDs 138. Each adapter 104 has a respective associated pair of detection LEDs 138 positioned near the adapter 104 so that a line of sight can be established between the pair of detection LEDs 138 if no connector 106 is attached to the patch side 114 of that adapter 104 and so that the line of sight will be broken if a connector 106 is attached to the patch side 114 of that adapter 104.

[0026] In the exemplary embodiment shown in FIG. 1, each detection LED 138 is implemented using an infrared LED 138 so that the light emitted from the detection diode 138 is not visible to the human eye.

[0027] In this exemplary embodiment, the infrared detection LEDs 138 that are used are not bidirectional— that is, they are not able to send and receive light in two directions (separated by about 180 degrees). In order to do this, an optical splitter/combiner is used (for example, implemented using a light pipe material). This enables each detection LED 138 to establish a line of sight with both of its neighboring detection LEDs 138. Alternatively, such bidirectional light paths could be created using two detection LEDs 138— one for each of the directions of communications. However, this would double the number of detection LEDs 138 used.

[0028] Each detection LED 138 is configured to operate in two mode, the first of which is a "transmit" or "TX" mode in which the detection LED 138 operates as an emitter and emits infrared light and the second of which is a "receive " or "RX" mode in which the detection LED 138 operates as a photo-detector and detects infrared light. In the exemplary embodiment shown in FIG. 1, each detection LED 138 is configured to operate in transmit mode in connection with determining if a connector is attached to the adapter 104 that is located to its right and is configured to operate in receive mode in connection with determining if a connector is attached to the adapter 104 that is located to its left. As a result of this arrangement, in this embodiment, an extra detection LED 139 is provided at the right end of the LED arrangement to be paired with the rightmost detection LED 138. This extra detection LED 139 is configured to operate in receive mode in connection with determining if a connector is attached to the rightmost adapter 104 shown in FIG. 1 while the rightmost detection LED 138 is configured to operate in transmit mode.

[0029] In the exemplary embodiment shown in FIG. 1, the visible LED 130 and detection LED 138 for each adapter 104 are coupled to the same input/output (I/O) line 140 of the controller 136. For ease of illustration, the connection between the shared I/O line 140 and the controller 136 is shown for only one I/O line 140 in FIG. 1, though it is to be understood that all of the I/O lines 140 are connected to the controller 136.

[0030] The controller 136 is configured to use these shared I/O lines 140 in a "normal" mode in which the controller 136 uses the shared I/O lines 140 to drive one or more of the visible LEDs 130 in order to cause them to emit visible light (for example, to provide a visual indication to help a technician carry out an electronic work order). The controller 136 is also configured to use these shared I/O lines 140 in a "presence detection" mode that is described in more detail below in connection with FIG. 2. This presence detection processing can be performed as a background task when the controller 136 is not using the shared I/O lines 140 in normal mode.

[0031] When the controller 136 uses the I/O lines 140 in normal mode to drive one or more of the visible LEDs 130 to cause them to emit visible light, the corresponding detection LEDs 138 will also be driven and emit IR light. However, since the detection LEDs 138 emit IR light, the illumination of a detection LED 138 while the I/O lines 140 are used in normal mode will not be visible and will not interfere with any visual indications that are being provided using the visible LEDs 130. Also, when the controller 136 uses the I/O lines 140 in presence detection mode to drive one of the detection LED 138 to cause it to emit IR light, the corresponding visible LED 130 will also be driven and will emit visible light. However, as described in detail below in connection with FIG. 2, in the presence detection mode, the shared I/O line 140 can be pulsed at a rate and with a duty cycle that results in the corresponding visible LED 130 producing light pulses that cannot be visibly perceived by a human. [0032] The detection LEDs 138 associated with the adapters 104 are used to detect the presence of connector inserted into the patch side 114 of the adapters 104. One method of doing this is shown in FIG. 2. FIG. 2 is a flow diagram of one exemplary method 200 of detecting the presence of connector. The particular embodiment of method 200 shown in FIG. 2 is described here as being implemented using the optical connector 100 of FIG. 1, though it is to be understood that other embodiments can be implemented in other ways (for example, in other patching systems such as patch panels for copper cabling).

[0033] In general, the processing associated with method 200 is performed for each of the adapters 104 in the tray 102 and can be performed as a background task when the controller 136 is not using the shared I/O lines 140 in normal mode.

[0034] Also, as noted above, each adapter 104 (or other port 102) has a respective associated pair of detection LEDs 138 or 139 positioned near that adapter 104 so that a line of sight can be established between the pair of detection LEDs 138 or 139 if no connector is attached to that adapter 104 and so that the line of sight will be broken if a connector is attached to that adapter 104;

[0035] Method 200 comprises operating a first detection LED 138 as an emitter (block 202). That is, for each pair of detection LEDs 138 or 139 mentioned above, a first one of the detection LEDs 138 in the pair is operated in transmit mode in order to emit infrared light. In the following description, the detection LED 138 in each pair operating in transmit mode is referred to here as the "transmitting" detection LED 138. In this exemplary embodiment, the controller 136 operates the transmitting detection LED 138 in transmit mode by using the associated I/O line 140 as an output to drive the transmitting detection LED 138 with a series of pulses. In this example, the pulses have a 50% duty cycle and are produced at a rate that is fast enough for the human eye to not register the visible light that is also produced by the visible LED 130 that shares the same I/O line 140 as the transmitting detection LED 138 (for example, at a rate where the visible LED 130 emits light for less than 10 milliseconds).

[0036] Method 200 further comprises operating a second detection LED 138 or 139 as a detector while the transmitting detection LED 138 is operated as an emitter (block 204). That is, for each pair of detection LEDs 138 or 139 mentioned above, a second one of the detection LEDs 138 or 139 in the pair is operated in receive mode while the transmitting detection LED 138 is operated in transmit mode. In the following description, the detection LED 138 or 139 that is operating in receive mode is referred to here as the "receiving" detection LED 138 or 139. In the exemplary embodiment described here, only one of the LEDs 138 is operated in transmit mode at a time with the other detections LED 138 and 139 are operated in receive mode. Also, in this example, the controller 136 operates each receiving detection LED 138 or 139 in receive mode by using the I/O line that couples that receiving detection LED 138 or 139 to the controller 136 as an input line.

[0037] Method 200 further comprises determining if a connector is inserted into the associated adapter 104 based on information generated from the receiving detection LED 138 or 139 (block 206).

[0038] As noted above, in this exemplary embodiment, each adapter 104 has a respective associated pair of detection LEDs 138 and/or 139 positioned near the adapter 104 so that a line of sight can be established between the pair of detection LEDs 138 and/or 139 if no connector 106 is attached to the patch side 114 of that adapter 104 and so that the line of sight will be broken if a connector 106 is attached to the patch side 114 of that adapter 104. That is, if no connector 106 is attached to the patch side 114 of that adapter 104, the receiving detection LED 138 or 139 in the pair should be able to detect a significant amount of the IR light emitted from the transmitting detection LED 138. If a connector 106 is attached to the patch side 114 of that adapter 104 and the line of sight that would otherwise exist is broken, the receiving detection LED 138 or 139 in the pair will not be able to detect a significant amount of the IR light emitted from the transmitting detection LED 138.

[0039] In this example, while the transmitting detection LED 138 in each pair is operated as an emitter and outputs a series of IR pulses, the controller 136 is configured to check the I/O line of the receiving detection LED 138 or 139 for that pair to see if a corresponding pulse signal is being received on that I/O line. If it is, the controller 136 determines that no connector is inserted into the patch side 114 of the adapter 104 associated with that pair of LEDs 138 or 139. If no pulse signal is received on that I/O line, the controller 136 determines that there is a connector inserted into the patch side 114 of the adapter 104 associated with that pair. In this latter case, the controller 136 can then update the status information maintained by the controller 136 for that adapter 136 to reflect that fact and to cause the RFID reader 132 to attempt to read any RFID tag 107 attached to the connector inserted into the patch side 114 of that adapter 104. An unsuccessful read attempt suggests that a foreign connector has been inserted into that adapter 104. The controller 136 can be configured to raise an alarm if that occurs. In this way, the presence of a connector inserted into the patch side 114 of an adapter 104 can be detected.

[0040] As noted above, the processing associated with method 200 can be performed for each adapter 104 in the tray 100. In the description of the following example, the eight adapters 104 shown in FIG. 1 are ordered from left to right such that the leftmost adapter 104 shown in FIG. 1 is referred to as the "first" adapter 104 and the rightmost adapter 104 shown in FIG. 1 is referred to as the "eighth" adapter 104. Likewise, the nine detection LEDs 138 and 139 shown in FIG. 1 are ordered from left to right such that the leftmost detection LED 138 shown in FIG. 1 is referred to as the "first" detection LED 138, the rightmost detection LED 138 shown in FIG. 1 is referred to as the "eighth" detection LED 138, and the extra detection LED 139 shown in FIG. 1 is referred to as the "ninth" detection LED 139. In one example, the first adapter 104 is checked for the presence of connecter in its patch side 120 as described above. This is done using a pair of detection LEDs that comprises the first detection LED 138 operating as an emitter and the second detection LED 138 operating as a detector. Then, the second adapter 104 is checked. This is done using a pair of detection LEDs that comprises the second detection LED 138 operating as an emitter and the third detection LED 138 operating as a detector. Then, the third adapter 104 is checked. This is done using a pair of detection LEDs that comprises the third detection LED 138 operating as an emitter and the fourth detection LED 138 operating as a detector. Then, the fourth adapter 104 is checked. This is done using a pair of detection LEDs that comprises the fourth detection LED 138 operating as an emitter and the fifth detection LED 138 operating as a detector. Then, the fifth adapter 104 is checked. This is done using a pair of detection LEDs that comprises the fifth detection LED 138 operating as an emitter and the sixth detection LED 138 operating as a detector. Then, the sixth adapter 104 is checked. This is done using a pair of detection LEDs that comprises the sixth detection LED 138 operating as an emitter and the seventh detection LED 138 operating as a detector. Then, the seventh adapter 104 is checked. This is done using a pair of detection LEDs that comprises the seventh detection LED 138 operating as an emitter and the eighth detection LED 138 operating as a detector. Then, the eighth adapter 104 is checked. This is done using a pair of detection LEDs that comprises the eighth detection LED 138 operating as an emitter and the ninth detection LED 139 operating as a detector. It is to be understood that other scanning sequences can be used.

[0041] The connector presence techniques described here can be used and

implemented in other ways. For they can be used in other types of PLM systems (for example, ninth wire PLM systems or PLM systems that use EEPROMS that are attached to connectors).

[0042] A number of embodiments have been described. Nevertheless, it will be understood that various modifications to the described embodiments may be made without departing from the spirit and scope of the claimed invention. Also, combinations of the individual features of the above-described embodiments are considered within the scope of the inventions disclosed here.

EXAMPLE EMBODIMENTS

[0043] Example 1 includes an apparatus comprising: a plurality of ports, each of the ports configured to have a respective connector attached thereto; and a plurality of light emitting diodes, wherein each port has a respective associated pair of light emitting diodes positioned near the port so that a line of sight can be established between the pair of light emitting diodes if no connector is attached to that port and so that the line of sight will be broken if a connector is attached to that port; wherein, for each pair of light emitting diodes, a first one of the light emitting diodes in the pair is operated as an emitter that emits light, a second one of the light emitting diodes in the pair is operated as a detector to detect the light emitted from the first one of the light emitting diodes, and the apparatus is configured to determine if a connector is attached to the associated port based on information generated by the second one of the light emitting diodes.

[0044] Example 2 includes the apparatus of Example 1, further comprising an RFID reader that is configured to read RFID tags attached to connectors.

[0045] Example 3 includes the apparatus of any of the Examples 1-2, wherein the apparatus comprises a patching system that comprises an optical connector tray on which the plurality of ports is housed.

[0046] Example 4 includes the apparatus of any of the Examples 1-3, wherein at least one of the plurality of light emitting diodes: is a member of a first pair of light emitting diodes associated with a first port and is operated as an emitter in connection with determining if a connector is attached to the first port; and is a member of a second pair of light emitting diodes associated with a second port and is operated as a detector in connection with determining if a connector is attached to the second port. [0047] Example 5 includes the apparatus of any of the Examples 1-4, wherein the plurality of light emitting diodes comprises infrared light emitting diodes.

[0048] Example 6 includes the apparatus of Example 5, further comprising a plurality of visible light emitting diodes that emit visible light.

[0049] Example 7 includes the apparatus of any of the Examples 1-6, wherein, for each pair of light emitting diodes, the respective first one of the light emitting diodes in the pair that is operated as the emitter emits a series of light pulses.

[0050] Example 8 includes the apparatus of any of the Examples 1-7, wherein the light emitting diodes are disposed on a printed circuit board.

[0051] Example 9 includes a a method for use with a plurality of ports and a plurality of light emitting diodes, wherein each port has a respective associated pair of light emitting diodes positioned near the port so that a line of sight can be established between the pair of light emitting diodes if no connector is attached to that port and so that the line of sight will be broken if a connector is attached to that port, the method comprising: for each pair of light emitting diodes: operating a first one of the light emitting diodes in the pair as an emitter that emits light; operating a second one of the light emitting diodes in the pair as a detector to detect the light emitted from the first one of the light emitting diodes; and determining if a connector is attached to the associated port based on information generated by the second one of the light emitting diodes.

[0052] Example 10 includes the method of Example 9, further comprising reading an RFID tag attached to a connector attached to a port.

[0053] Example 11 includes the method of any of the Examples 9-10, wherein the plurality of ports and plurality of light emitting diodes are a part of a patching system. [0054] Example 12 includes the method of any of the Examples 9-11, wherein at least one of the plurality of light emitting diodes: is a member of a first pair of light emitting diodes associated with a first port and is operated as an emitter in connection with determining if a connector is attached to the first port; and is a member of a second pair of light emitting diodes associated with a second port and is operated as a detector in connection with determining if a connector is attached to the second port.

[0055] Example 13 includes the method of any of the Examples 9-12, wherein the plurality of light emitting diodes comprises infrared light emitting diodes.

[0056] Example 14 includes the method of Example 13, further comprising a plurality of visible light emitting diodes that emit visible light.

[0057] Example 15 includes the method of any of the Examples 9-14, wherein, for each pair of light emitting diodes, the respective first one of the light emitting diodes in the pair that is operated as the emitter emits a series of light pulses.

LIST OF REFERENCE NUMERALS AND CORRESPONDING FEATURES

100 communication device

102 ports

104 adapter

106, 108 optical connectors

107 RFI D tags

110, 112 fibers

114, 116 sides

118 clip

120 patch cords

122 fixed optical cabling

126 printed circuit board

128 RFI D antenna or coil

130 light emitting diode

132 RFI D reader

134 multiplexer

136 controller

138, 139 detection light emitting diodes

140 shared input/output line

Claims

1. An apparatus (100) comprising:

a plurality of ports (102), each of the ports (102) configured to have a respective connector (106) attached thereto; and

a plurality of light emitting diodes (138, 139), wherein each port (102) has a respective associated pair of light emitting diodes (138, 139) positioned near the port (102) so that a line of sight can be established between the pair of light emitting diodes (138, 139) if no connector (106) is attached to that port (102) and so that the line of sight will be broken if a connector (106) is attached to that port (102);

wherein, for each pair of light emitting diodes (138, 139), a first one of the light emitting diodes (138) in the pair is operated as an emitter that emits light, a second one of the light emitting diodes (138, 139) in the pair is operated as a detector to detect the light emitted from the first one of the light emitting diodes (138), and the apparatus is configured to determine if a connector (106) is attached to the associated port (102) based on information generated by the second one of the light emitting diodes (138, 139).

2. The apparatus (100) of claim 1, further comprising an RFID reader (132) that is configured to read RFID tags (107) attached to connectors (106).

3. The apparatus (100) of claim 1, wherein the apparatus (100) comprises a patching system that comprises an optical connector tray (100) on which the plurality of ports (102) is housed.

4. The apparatus (100) of claim 1, wherein at least one of the plurality of light emitting diodes (138): is a member of a first pair of light emitting diodes (138, 139) associated with a first port (102) and is operated as an emitter in connection with determining if a connector (106) is attached to the first port (102); and

is a member of a second pair of light emitting diodes (138) associated with a second port (102) and is operated as a detector in connection with determining if a connector (106) is attached to the second port (102).

5. The apparatus (100) of claim 1, wherein the plurality of light emitting diodes (138, 139) comprises infrared light emitting diodes.

6. The apparatus (100) of claim 5, further comprising a plurality of visible light emitting diodes (130) that emit visible light.

7. The apparatus (100) of claim 1, wherein, for each pair of light emitting diodes (138, 139), the respective first one of the light emitting diodes (138) in the pair that is operated as the emitter emits a series of light pulses.

8. The apparatus (100) of claim 1, wherein the light emitting diodes (138, 139) are disposed on a printed circuit board (126).

9. A method for use with a plurality of ports (102) and a plurality of light emitting diodes (138, 139), wherein each port (102) has a respective associated pair of light emitting diodes (138, 139) positioned near the port (102) so that a line of sight can be established between the pair of light emitting diodes (138, 139) if no connector (106) is attached to that port (102) and so that the line of sight will be broken if a connector (106) is attached to that port (102), the method comprising:

for each pair of light emitting diodes (138, 139):

operating a first one of the light emitting diodes (138) in the pair as an emitter that emits light; operating a second one of the light emitting diodes (138, 139) in the pair as a detector to detect the light emitted from the first one of the light emitting diodes (138); and

determining if a connector (106) is attached to the associated port (102) based on information generated by the second one of the light emitting diodes (138, 139).

10. The method of claim 9, further comprising reading an RFID tag (107) attached to a connector (106) attached to a port (102).

11. The method of claim 9, wherein the plurality of ports (102) and plurality of light emitting diodes (138, 139) are a part of a patching system.

12. The method of claim 9, wherein at least one of the plurality of light emitting diodes (138):

is a member of a first pair of light emitting diodes (138, 139) associated with a first port (102) and is operated as an emitter in connection with determining if a connector (106) is attached to the first port (102); and

is a member of a second pair of light emitting diodes (138, 139) associated with a second port (102) and is operated as a detector in connection with determining if a connector (106) is attached to the second port (102).

13. The method of claim 9, wherein the plurality of light emitting diodes (138, 139) comprises infrared light emitting diodes.

14. The method of claim 13, further comprising a plurality of visible light emitting diodes (130) that emit visible light.

15. The method of claim 9, wherein, for each pair of light emitting diodes (138, 139), the respective first one of the light emitting diodes (138) in the pair that is operated as the emitter emits a series of light pulses.