REDUNDANCY AND INTEROPERABILITY IN MULTI-CHANNEL OPTOELECTRONIC DEVICES

• US 20090060520A1
• Filed: 02/28/2008
• Published: 03/05/2009
• Est. Priority Date: 02/28/2007
• Status: Active Grant

• Current Assignee: II-VI Delaware, Inc. (Coherent Corp.)
• Original Assignee: Finisar Corporation (II-VI Incorporated)
• Inventors: Aronson, Lewis B., Cole, Christopher R., Douma, Darin James
• Granted Patent: US 8,861,952 B2
• Time in Patent Office: Days
• US Class Current: 398/140
• CPC Class Codes: H04B 10/032 using working and protection systems H04J14/0287 takes precedence
• CPC Class Codes: H04B 10/0793 Network aspects, e.g. central monitoring of transmission parameters
• CPC Class Codes: H04B 10/0795 Performance monitoring; Measurement of transmission parameters
• CPC Class Codes: H04J 14/02 Wavelength-division multiplex systems

Abstract

A multi-channel optoelectronic device is configured to establish a redundant status link with a remote device. The optoelectronic device can transmit N transmit optical signals to the remote device over a plurality of transmit channels and receive N receive optical signals from the remote device over a plurality of receive channels. The optoelectronic device includes one or more spare transmit and receive channels. When used with a remote device having spare transmit and receive channels, each device can establish a status link with the other and use the status link to switch out transmit and/or receive channels to identify and permanently switch out the worst transmit and/or receive channels. Alternately, the device can interoperate with a non-status-link enabled remote device by determining that the remote device is not status-link enabled, transitioning to a low transmit power mode, and transmitting and receiving over a plurality of default transmit and receive channels.

Claims

1. An optoelectronic device configured to establish and detect redundant status links with a status-link enabled remote device, the optoelectronic device comprising:

a plurality of optical transmitters configured to emit a plurality of transmit optical signals representative of a plurality of transmit electrical signals, each of the plurality of transmit optical signals including primary data;

a plurality of optical receivers configured to receive a plurality of receive optical signals and generate a plurality of receive electrical signals, each of the plurality of receive optical signals including primary data; and

a controller configured to;

effectively modulate transmitter bias currents for at least two of the optical transmitters with a low frequency status link signal such that first status data is simultaneously conveyed with primary data on at least two of the plurality of transmit optical signals; and

detect second status data simultaneously received with primary data on at least two of the plurality of receive optical signals.

2. The optoelectronic device of claim 1, wherein:

the plurality of optical transmitters includes;

a plurality of default optical transmitters equal in number to the plurality of transmit optical signals, also being equal in number to the plurality of transmit electrical signals, and one or more spare optical transmitters; and

the plurality of optical receivers includes;

a plurality of default optical receivers equal in number to the plurality of receive optical signals, also being equal in number to the plurality of receive electrical signals, and one or more spare optical receivers.

3. The optoelectronic device of claim 2, further comprising:

a plurality of demultiplexers configured to route the plurality of transmit electrical signals from a corresponding number of electrical inputs to a corresponding number of the plurality of optical transmitters, leaving one or more unused optical transmitters; and

a plurality of multiplexers configured to route the plurality of receive electrical signals from a corresponding number of the plurality of optical receivers to a corresponding number of electrical outputs, leaving one or more unused optical receivers.

4. The optoelectronic device of claim 3, wherein the optoelectronic device is configured to interoperate with a remote device that is not status-link enabled and that includes the same number of optical receivers as transmit optical signals for receiving the transmit optical signals and the same number of optical transmitters as receive optical signals for generating the receive optical signals.

5. The optoelectronic device of claim 4, wherein interoperating with the remote device that is not status-link enabled includes:

determining that the remote device is not status-link enabled;

transitioning to or maintaining operation in a low transmit power mode;

configuring the demultiplexers to route the plurality of transmit electrical signals through the plurality of default optical transmitters, the plurality of default optical transmitters being communicably coupled to the optical receivers of the remote device; and

configuring the multiplexers to route the plurality of receive electrical signals from the plurality of default optical receivers, the plurality of default optical receivers being communicably coupled to the optical transmitters of the remote device.

6. The optoelectronic device of claim 3, wherein the remote devices includes a plurality of optical receives equal in number to the number of the optoelectronic device'"'"'s plurality of optical transmitters, and a plurality of optical transmitters equal in number to the number of the optoelectronic device'"'"'s plurality of optical receivers, and wherein the optoelectronic device is configured to switch out one or more of its optical transmitters, optical receivers, or both, and the remote device is configured to switch out one or more of its optical transmitters, optical receivers, or both.

7. In a multi-channel optoelectronic device, a method of providing automatic redundancy, the method comprising:

in an optoelectronic device having two or more active transmit channels, one or more spare transmit channels, two or more active receive channels, and one or more spare receive channels, establishing a redundant status link over at least two of the active transmit channels with a remote device;

switching out at least one of the active transmit or receive channels such that the at least one of the active transmit or receive channels becomes a spare transmit or receive channel and at least one of the one or more spare transmit or receive channels becomes an active transmit or receive channel;

identifying the at least one switched out transmit or receive channel to the remote device over the redundant status link, wherein the remote device switches out a corresponding at least one active receive or transmit channel of the remote device;

measuring and storing digital bias current values for the active and spare transmit channels, the active and spare receive channels, or both, before and after the switching out; and

identifying one or more worst transmit channels, one or more worst receive channels, or both, using the digital bias current values.

8. The method of claim 7, wherein metrics about one or more of the transmit channels, receive channels, or both, are measured and stored in the optoelectronic device prior to being used with the remote device for use in identifying the one or more worst transmit channels, one or more worst receive channels, or both.

9. The method of claim 7, wherein the method begins in response to a start event, a start event including one or more of:

powering up link hardware and a controller of the optoelectronic device;

resetting the link hardware and the controller; and

plugging in the link hardware.

10. The method of claim 7, wherein establishing a redundant status link includes:

generating a status link modulation signal from status data;

effectively applying the status link modulation signal to at least two of two or more transmitter bias currents to generate at least two status-link modulated transmitter bias currents;

modulating each of the at least two status-link modulated transmitter bias currents with a different one of at least two of two or more primary data modulation signals to obtain at least two resulting signals;

providing the at least two resulting signals to at least two of the active transmitters for transformation into at least two optical signals; and

transmitting the at least two optical signals to the remote device,

wherein the remote devices receives the at least two optical signals using at least two photodetectors and detects the status data by detecting the receiver bias currents of the at least two photodetectors.

11. The method of claim 7, wherein identifying one or more worst transmit channels, one or more worst receive channels, or both, using the digital bias current values includes one or more of:

identifying one or more corresponding optical transmitters of the optoelectronic device having the highest transmitter bias current values; and

identifying one or more corresponding optical receivers of the optoelectronic device having the lowest receiver bias current values.

12. The method of claim 11, further comprising switching out the one or more worst transmit channels, one or more worst receive channels, or both.

13. The method of claim 7, further comprising, receiving identification of at least one switched out transmit or receive channel of the remote device over a redundant status link established by the remote device with the optoelectronic device over at least two of the active receive channels and in response, switching out a corresponding at least one active receive or transmit channel of the optoelectronic device.

14. The method of claim 7, wherein the optoelectronic device performs one or more additional iterations of switching out at least one active transmit or receive channel, identifying the at least one switched out transmit or receive channel to the remote device over the redundant status link, and measuring and storing digital bias current values until a timer of the optoelectronic device indicates that a predetermined time for performing the iterations has expired.

15. A method of interoperating a status-link enabled device with a non-status-link enabled device, the method comprising:

in a multi-channel status-link enabled optoelectronic device including a plurality of default transmit channels and one or more spare transmit channels and being communicably coupled to a remote device, determining that the remote device is not status-link enabled;

transitioning to or maintaining operation in a low transmit power mode in the optoelectronic device; and

establishing a plurality of main communication links with the remote device on the plurality of default transmit channels.

16. The method of claim 15, wherein determining that the remote device is not status-link enabled includes one or more of:

transmitting an acknowledgment request to the remote device using a status link and not receiving acknowledgment from the remote device within a prescribed time period; and

the remote device establishing main communication links but not a status link with the optoelectronic device over a plurality of receive channels of the optoelectronic device.

17. The method of claim 15, wherein the low transmit power mode includes sufficient link budget to establish the plurality of main communication links on the plurality of default transmit channels, while the total transmit power of the default transmit channels remains at or below a maximum eye safety limit.

18. The method of claim 15, wherein transitioning to a low transmit power mode in the optoelectronic device includes reducing transmitter bias currents supplied to the default transmit channels.

19. The method of claim 15, wherein the default transmit channels include the ten center fibers of a twelve fiber patch cord.

20. The method of claim 15, wherein the optoelectronic device further includes a plurality of default receive channels and one or more spare receive channels, and wherein the remote device establishes a plurality of main communication links with the optoelectronic device on the plurality of default receive channels.