Intelligent Optical Bypass Switch Implementation

Remote switches plate B passively monitoring optical power of the transmit fibers.Since the transceivers are continually transmitting Manchester-coded data or idle tone, this criterion is used in determining whether the switch should activate.When the optical signal is lost on a transmit fiber.It is determined that one of the following failure modes has occurred: either the LED has failed, the transceiver has lost power or been destroyed, or the building to -ring stub has been destroyed, or the building of a ring stub has been destroyed.In this event, the transceiver is automatically bypassed until repairs or replacement can be done.

A complete switch is composed of two identical channels.Each channel services one fiber of the dual counterrotating ring.At the coupling points, ,10 percent of the transmitted optical power are taped off and detected.A PIN photodiode with a low pass preamplifier is utilized to detect the average optical power incident on the detector.The detected power is amplified and compared to a threshold to be transformed into a logic high or low.The resulting digital value is used to place a latching optical switch reduces the abnormal electrical power requirements normally associate with the holding current in the traditional fails safe Mechanical Optical Switch  implementations.Additional circuitry gets power to the switch drivers and provides battery backup and recharge.

Prototype o two channel remote bypass switches were constructed.The prototype was placed in a simulated network environment to measure insertion losses, sensitivity, speed of response, and power consumption, In addition, operational test was carried out to examine switching response.Operation ofthe battery backup, and interoperability with the transceivers.

Operational tests showed the switch performed as designed.Switch transitions occurred at the preset threshold levels and within adequate time.Upon the loss of external power, the battery backup was noted to function correctly.
The laboratory prototype of the intelligent Optical Bypass Switch  was integrated into the survivable network testbed and produced the expected results.The use of this type of bypass switch in the final implementation can significantly enhance the probability of network survivability.


The laboratory prototype of the intelligent optical bypass switch was integrated into the survivable network testbed and produced the expected results.The use of this type of bypass switch in the ultimate implementation can significantly enhance the probability of network survivability.The MEMS Optical Switch design described above has been tailored for use in this application.However, the concept could be applied to other fiber optic ring architecture.In these applications, the switch would have to rely on the presence of the token or some other keep alive signal to determine the status of its.

A fiber optic controlled switch has been identified as a potentially promising alternative to the conventional wall mounted light switch which uses copper wire normally run inside conduit.The article paper describes the considerations prior to the switch design and the problems met during fabrication and design, as part of the lighting energy conservation research program hosted by the National Research Council of Canada.

The Fiber Optical Switch which is outlined below is schematically illustrated.The entire switch system is made up of three separate subsystems: the control module, the fiber, as well as the wall switch.The control module is truly a three terminal devices connecting in the electrical line.The module houses the triac switch. Could be much longer, as the attenuation properties of the fiber were minor in comparison to the other system losses.The wall switch is a simple mechanical devices; the two fibers entering are close and aligned together so that light is referred from one to the other.Sliding path, thereby triggering the control module, even though the light -emitting diode source and the photo -duplication detector.The light-emitting diode remains on whether the triac switch is placed on or off.The light from the light-emitting diode is delivered to the wall switch through one of the Fiber Optic Cable Products .The same light is passed back from the wall switch to the control module interfaces with the photo-darlington trigger the triac inside the control module.The optical fiber used was 300 micron core plastics clad silica fiber with a nylon jacket but could easily have been a twin type fiber with adhesive backing to permit easy installation on wall surfaces.The length of each of the two fiber links was 13 meters.

Are attractive because the switch assembly could then be factory packaged without the necessity for a tradesman to make fiber connections at the job site.As the wall switch requires no switch box and is no larger than a cigarette packer, there is greater flexibility in both its design and location, installation of the fiber optic solutions control system requires connecting the control module in the lamp circuit in the ceiling plenum to the wall switch by a dual fiber.Both the optic fiber and the wall switch can be fitted to the surface of the wall switch can be installed on the surface of the wall since both are completely isolated elecrically.The length of optic fiber can be adjusted either by cutting G on site or by coiling extra fiber lengths in the ceiling plenum.The latter lengths.


Some great benefits of the fiber optic switch include: Damp,or generally hostile environments,and flexibility ,as office spaces often undergo changes in work station layout the fiber optic switch can be covered over or relocated very easily, low installation costs because "control wires" and the wall switch can be surface mounted;the switches can be installed on external walls without puncturing vapour barriers;the switches can be installed close to or at work stations;there is increased safety since the switch is completely isolated from the power circuit the electrical isolation means that the switch can be installed safely in explosive.