WO2019226705A1

WO2019226705A1 - Apparatus and method for automated tuning of optical power, extinction ratio, and crossing of multi-channel eye diagrams simultaneously

Info

Publication number: WO2019226705A1
Application number: PCT/US2019/033404
Authority: WO
Inventors: Gap Youl LYU; Edward CORNEJO
Original assignee: Macom Technology Solutions Holdings, Inc.
Priority date: 2018-05-21
Filing date: 2019-05-21
Publication date: 2019-11-28

Abstract

A method for establishing the settings in a multichannel optic module that includes connecting the optic module to an optimization module and establishing initial settings in the multichannel optic module for each channel such that the settings include bias voltage, modulation voltage, and crossing voltage. This method then sets the overshoot to a target overshoot value for each channel and adjusting the settings to optimize the eye mask margin and minimize bias voltage. The settings are generated at different temperatures to create and these settings across temperature are stored in a memory of the optic module. The optimization module analyzes an eye diagram created by optic signal from the multichannel optic module and uses PID control determine optimal setting for the multichannel optic module. The target overshoot value may be 20% of voltage amplitude.

Description

APPARATUS AND METHOD FOR AUTOMATED TUNING OF OPTICAL POWER, EXTINCTION RATIO, AND CROSSING OF MULTI-CHANNEL

EYE DIAGRAMS SIMULTANEOUSLY

1. Field of the Invention.

[0001] The invention relates to optic signal power control and in particular to a method and apparatus to optimize an optic signal parameters.

2. Related Art.

[0002] Data communication over an optical fiber using light or optic signal is a widely used method short and long-haul data communication. Using optical communication system, data rates in excess of 100 Gbits/second with wavelength division multiplexing (WDM) technologies are achieved. One key to enable optic communication systems is the ability to accurately encode the data onto an optic signal and, upon receipt, decode the optic signal to recreate the data. One visual observational tool used to determine the quality of the received signal is an eye diagram. An eye diagram is formed by a plot of the received signal, over time, over temperature which causes the signal to form one or more features that appear as eyes.

[0003] Figure 1 illustrates an example eye diagram plot. This example plot is from a four channel system, having channel 1 plot 104, channel 2 plot 108, channel 3 plot 112, and channel 4 plot 116. The eye diagrams are formed by plots of the signal over time as the signal is at and in transition to the different signal levels. As can be seen in Figure 1, the signal plots of the received signals on each channel differ from one another. In particular, the signal received on channel 1 is different than the signal received on channel 4. As compared to channel 1, the channel 4 signal 116 has significantly more overshoot 124 than the overshoot 120 of the channel 1 plot 104. In addition, the central eye opening 134 in channel 4 signal plot 116 is collapsed compared to the central eye openingl34 in channel 4 signal plot 116. In addition, other signal features are different in the channel 4 signal plot 116 compared to the channel 1 signal plot 104. This interferes with signal decoding and will result in lower effective bit rate, higher bit error rates, or both. Thus, it is desired to open the eye of the eye diagram to improve signal decoding.

[0004] Figure 2 illustrates a signal plot showing an exemplary eye diagram with relevant signal plot features labeled. The eye diagram plot 204 is formed by signals 208. The signal plot 204 includes a central eye 230. The signal 208 is further defined by its average value Vavg 212 and a total amplitude Vamp 216 of the signal which is the difference between the Vtop and Vbottom. The maximum voltage of the signal 208 is defined as Vmax 220. The amount that the voltage maximum Vmax 220 is great than Vtop is defined as the overshoot 224.

[0005] Figure 3 illustrates a signal plots of optical device output intensity versus current for four example optic signal output devices. Intensity is on the vertical axis 308 while current is represented on the horizontal axis 312. Four signal plots are shown for channels 1-4, 320, 324, 328, 332. The modulation current 340 is shown in relation to the intensity 344 in relation to modulation current and average power. In this plot, the drive current versus intensity of each channel are different, which represent different operating conditions for proper eye diagrams with bias current and modulation current.

SUMMARY

[0006] To overcome the drawbacks of the prior art and provide additional benefits, a method for automated tuning of an optic signal toward uniformity across channels is disclosed comprising providing an eye diagram optimization system and an optic module having a first channel optic system which is configured to generate a first optic signal and a second channel optic system configured to generate a second optic signal. Then, this method establishes starting settings for first channel optic system and generates a first channel optic signal with the first channel optic system. Thereafter, this method establishes overshoot for the first channel optic signal as a percentage of voltage amplitude and establishes overshoot for the second channel optic signal as a percentage of voltage amplitude. This method also maximizes eye mask margin for the first channel optic signal while minimizing bias voltage to reduce heat generation and also maximizes an eye mask margin for the second channel optic signal while minimizing bias voltage to reduce heat generation. Thereafter, tuning occurs on each channel to achieve a uniform eye diagram for the first channel optic signal and the second channel optic signal and storing the settings in a memory associated with the optic module for use during operation.

[0007] In one embodiment, this method further comprises a third channel optic system and a fourth channel optic system. It is contemplated that the settings include: bias voltage, modulation voltage, and crossing voltage. The overshoot percentage of voltage amplitude is between 15% and 25%. In one configuration, this method may further comprise repeating the turning at different temperatures to generate settings for different temperatures and storing the settings for different temperatures in the memory. It is contemplated that the eye diagram optimization system monitors average optical power, eye amplitude, overshoot and crossing point. The optic module may further comprise a signal detection module configured to convert the first channel optic signal to an electrical signal to generate one or more feedback signals and a power control module configured to receive and process the feedback signal and provide power control and extinction ratio control feedback signal for optic module.

[0008] Also disclosed is a system for optimizing settings of a multichannel optic module. In one configuration this system includes an optic module comprising a memory configured to store optic module settings, and a processor configured to access the stored optic module settings and implement the settings in the optic module. Also, part of the optic module are one or more light sources configured to generate an optic signal based on the input signal and the settings. Also, part of this system is an optimization module configured to receive and analyze the one or more optic signals. The aspects analyzed include optic power, eye amplitude, overshoot. Responsive to the analyzing, the system generates the settings. This occur such that the optimization module in combination with the optic module is configured to set the overshoot to a target overshoot value for all channels and optimizing eye mask margin in the one or more optic signals while minimizing bias voltage. Then, for different temperatures, the system generates resulting bias voltage, modulation voltage and crossing voltage to form optic module data across temperature. The optic module data across temperature is stored in the optic module for use during operation. [0009] In one embodiment, the target overshoot value is 20% of voltage amplitude. In one configuration setting the overshoot to a target overshoot value for all channels comprises adjusting bias voltage, modulation voltage, and crossing voltage. It is contemplated that the bias voltage is minimized to reduce optic module heating.

[0010] It is also contemplated that the optic module may further comprise a signal detection module and a power control module. The signal detection module includes a photodetector and a peak detector such that the photodetector is configured to convert an optic signal to an electrical signal and the detector. The power control module includes an automatic power control unit and an automatic extinction ratio control unit configured to provide power control and extinction ratio control, which in turn controls bias current and modulation current.

[0011] Also disclosed is a method for establishing the settings in a multichannel optic module comprising connecting the optic module to an optimization module and establishing initial settings in the multichannel optic module for each channel such that the settings including bias voltage, modulation voltage, and crossing voltage. This method also sets the overshoot to a target overshoot value for each channel and adjusts the settings to optimize the eye mask margin and minimize bias voltage. This method then generates the settings at different temperatures to create settings across temperature and stores the settings across temperature in a memory of the optic module.

[0012] In one embodiment, the optimization module analyzes an eye diagram created by optic signal from the multichannel optic module and uses PID control determine optimal setting for the multichannel optic module. In one configuration, the target overshoot value is 20% of voltage amplitude. It is also contemplated that the overshoot occurs in real time mode and performing eye diagram analysis occurs based on signal analysis on signals accumulated over time. In one embodiment the setting overshoot occurs using a PID control loop. This method may further comprise fine tuning the settings to make the eye diagram for each channel uniform.

[0013] Other systems, methods, features and advantages of the invention will be or will become apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description, be within the scope of the invention, and be protected by the accompanying claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. In the figures, like reference numerals designate corresponding parts throughout the different views.

[0015] Figure 1 illustrates an example eye diagram plot. This example plot is from a four channel system, having channel 1 plot 104, channel 2 plot 108, channel 3 plot 112, and channel 4 plot 116.

[0016] Figure 2 illustrates a signal plot showing an exemplary eye diagram with relevant signal plot features labeled.

[0017] Figure 3 illustrates a signal plots of optical device output intensity verses current for four example optic signal output device.

[0018] Figure 4 illustrates signal plots for channel 1, channel 2, channel 3 and channel 4 after the overshoot is made uniform across the channels.

[0019] Figure 5 A illustrates a flow chart of an example method of operation.

[0020] Figure 5B illustrates an alternative example method of operation.

[0021] Figure 6, 6 A and 6B illustrate an exemplary block diagram of an eye diagram optimization and data collection system. [0022] Figure 7 illustrates an exemplary optic fiber communication link which is an example environment of use.

DETAILED DESCRIPTION

[0023] To overcome the drawbacks of the prior art, a method and apparatus is disclosed to make the signal plots across the four channels uniform with regard to overshoot, and then perform signal tuning on the uniform signal plots to optimize the eye diagram. To make the signal plots uniform across the four channels, this method operation adjusts the overshoot of the signal on each of the channels to be uniform across channels. In one embodiment, this step sets the overshoot to 20% of the Vamp, but in other embodiments the overshoot may be set across all channels, to any other value, including zero. In other embodiments the overshoot is not exactly the same but generally similar or within a few percent. Once the overshoot is set to a uniform value across all channels, the other signal parameters may be set to establish a desirable eye diagram plot balanced with signal power.

[0024] vx illustrates signal plots for channel 1, channel 2, channel 3, and channel 4 after the overshoot is made uniform across the channels. As can be seen in the plots, the overshoot 404, 408, 412, 416 for the signal on each of the channels is generally uniform after processing to standardize the overshoot to a uniform level.

[0025] Figure 5 illustrates a flow chart of an example method of operation. This is but one possible method of operation and it is contemplated that other methods of operation are possible. Prior to the execution of this method of signal adjustment of eye diagram adjustment across all channels, it is expected that a multiple channel optical module and signal generation system is provided. A test and optimization module may be also be provided to process the optic signals from each channel and then calculate settings to optimize and make uniform the resulting signal patterns, which may be referred to as the eye diagrams. In general, this method occurs at the time of manufacture or configuration of the module to generate the optic module operating parameters. During operation the derived settings are stored in the optic module. At a step 508 the method sets the initial conditions for multi-channel optical transceivers. This occurs across all channels of the multichannel module. This may be a default setting from the factory or set by a customer based on a best estimate for optic module settings, which may vary based on application and circuit integration. Exemplary values that are set in step 508 may include but are not limited to bias voltage VB, modulation voltage VM, and crossing voltage VX. Exemplary setting may be VB (Voltage Bias): 120 in a range of 110 -160, VB (Voltage Modulation): 120 in a range of 110 -160, and VB (Voltage Crossing): 45 in a range of 40-50.

[0026] At a step 512 this method of operation sets the overshoot target value to which overshoot is to be adjusted. This is typically a percentage of voltage amplitude Vamp. In one embodiment overshoot is set to 20%, but in other embodiments, other percentage values or fixed voltage values may be used for the overshoot target. This occurs for each channel in a multi-channel system. Overshoot percentage is defined at overshoot percentage = 100 * Vovershoot / Vamp, which can also be written as 100* (Vmax- Vtop)/Vamp or 100* Vovershoot/Vamp. This occurs for each channel. Detection of overshoot can be done through use of an auto-sensing oscilloscope, digital communication analyzer (DAC), on the module during a tuning mode, settings determination mode, or during operation. [0027] At a step 516 this method of operation uses a PID (proportional integral derivative) control loop to quickly and accurately adjust overshoot by adjusting or using bias voltage VB, modulation voltage VM, and extinction voltage VX. This step controls VB/VM/VX to the target values quickly without over damping. PID control is discussed below in greater detail.

[0028] At a step 520, the system maximizes the eye mask margin (EMM) depending on and based on the overshoot percentage while also minimizing the bias voltage to reduce power consumption / heat output to reduce self-heating on the laser diodes. In multi-laser diode optic modules, heat generated by one laser diode and driver affects operation and longevity of the components (laser diodes) of the other channels. To reduce this unwanted cross-affect, bias voltage is minimized to the extent possible while still maintaining an ideal eye diagram and eye opening. This can be especially true for power drop on MUX-output owing to the wavelength which can be minimized. At a step 524, the system optimizes the EMM depending on the overshoot percentage. The overshoot is a dominate factor in controlling and improving the EMM.

[0029] At a step 528 of Figure 5, the method of operation copies, to the memory of the optic module, the bias voltage VB, modulation voltage VM, and extinction voltage VX settings for the eye diagrams for more precise measurement of optical power, extinction ratio, crossing point, over time, and over temperature with accumulated eye diagram readings. The system operation will change at different temperatures, so it is preferred to calculate and store optimized operation setting at different temperatures. In this embodiment, the set of the final values of VB/VM/VX are copied to flash memory of the microprocessor on the module. Then, at a step 532, the system fine tunes each channel to establish a uniform eye diagram for each channel in the multi-channel system using the optic module processor. Thus, after the overshoot is made uniform across all channels, then the eye diagram tuning may occur by adjusting the overshoot/voltage/power parameters of the optic module make the eye diagrams uniform.

[0030] At a step 536 the system, using the method disclosed herein, sets the final values for bias voltage VB, modulation voltage VM, and extinction voltage VX for the multi channel TOSA transceiver to optimize the eye diagrams. At a step 540, all of the bias voltage VB, modulation voltage VM, and extinction voltage VX values are controlled and fully automated, with a GUI (graphical user interface) for interface by a user.

[0031] Figure 5B illustrates a similar but simplified method of operation. At a step 550, a user or system set initial conditions for the multichannel optical transceiver which may include, but is not limited to bias voltage, modulation voltage, and crossing voltage. Then at step 554, the system, such as a test and optimization module to which the optic module connects for set up, sets overshoot as a percentage or ratio of voltage amplitude for each channel. At a step 558, the test and optimization module adjusts overshoot to be uniform across all channels by adjusting bias voltage, modulation voltage, and crossing voltage. At a step 562, the module maximizes the EMM while minimizing or reducing bias voltage to reduce heat generation. Next, at a step 566, the module optimizes the eye mask margin for each channel, and at a step 570, the test and optimization module copies the bias voltage, modulation voltage and extinction voltage to the memory of the optic module, which is accessible by an optic module processor.

[0032] At a step 574, the optic module fine tunes each eye diagram for each optic signal to establish uniform eye diagrams across channels. At a step 578, the optic module sets the final values for bias voltage, modulation voltage, and crossing voltage for each channel to optimize eye diagrams. Finally, at a step 582, the tuning process finishes, and the optic module may be deployed to the field with the automated control for the optic module settings to optimize the eye diagram across different temperatures.

[0033] Figure 6 illustrates an exemplary block diagram of an eye diagram optimization and data collection system. This is but one possible configuration of elements and it is contemplated that one of ordinary skill in the art may arrive at different configurations without departing from the scope of the invention. In general, this example embodiment shows an optic signal transmitter configured in connection with a signal analyzer and optimization system. Starting on the left-hand side of Figure 6, a microprocessor 604 provides control input to a light source driver 608. An input signal 632, such as data or a test/training signal, is also provided to the light source driver 608. The light source driver 608 provides a bias signal and a modulation signal to a light source 612, such as a laser or LED. The light source 612 generates an optic signal that is typically, during operation and the data collection and system optimization phase, transmitted on an optic fiber. In this embodiment, during a signal analysis and optimization session, the optic signal 616 is provided to a test and optimization module 620. In the test and optimization module 620, the optic signal is analyzed and optimization settings are generated and stored for use later when the optic module is installed in the field. The output of the test and optimization module 620 is provided to the microprocessor 604 for processing. A memory 624 is in communication with the microprocessor 604. The output from the test and optimization module 620 provides data that the processor 604 uses to generate and store optimized settings for the optic transmitter, including bias current and modulation current settings, to improve the optic signal as compared to prior art performance. These optimized settings are stored in the memory 624 for use by the optic module when the optic module in use for data communication. Groups of optimized settings may be generated over different temperatures and stored in memory for use in the field during operation based on the temperature of the module.

[0034] A detailed discussion of Figure 6 is now provided starting with a startup phase, through a data collection and analysis phase including creation of optimized optic module data. Initially and prior to optimization, the microprocessor 604 outputs a starting level bias current value 628, a bias current control signal 636, and a modulation current control signal 638 to the light source driver 608.

[0035] In this example embodiment, the light source driver 608 includes a bias current generator 640, a modulation current generator 642, a bias current controller 644, and a modulation current controller 646. The outputs of the bias current generator 640 and the bias current controller 644 both feed into a summing junction 648. The outputs of the modulation current generator 642 and the modulation current controller 646 both feed into a summing junction 650. The outputs of the summing junctions 648, 650 feed into the light source 612 to provide the bias current and modulation current to drive and control light source operation and achieve optic signal output.

[0036] In operation, the modulated signal 632 is provided to the driver 608. At this point, the modulated signal 632 is a training or test signal but when configured and installed in the field, it will be a data signal. The modulated signal 632 can be adjusted, based on the control signal 638 by the modulation current controller 646. This adjustment may be based on different factors including the optimized settings discussed herein. Similarly, the bias signal 628 is provided to the bias current generator 640 to set the biasing for the light source 612. The bias current can be adjusted upward or downward from the baseline level using the bias control signal 636, which is processed by the bias current controller 644. The output of the bias current controller 644 adjusts the bias current from the bias current generator 640 in the summing junction 648 prior to providing the bias current to the light source 612.

[0037] In reference to the test and optimization module 620, the optic signal 616 from the light source 612 is received and analyzed. In one embodiment, the test and optimization module 620 includes a DCA (digital communication analyzer) 652 configured to analyze the eye diagram of the optic signal. Based the analysis, one or more of the average power 654, eye amplitude 656, overshoot 658, and crossing point 660 are derived and provided to a computer or processing unit 662. The average power 654, eye amplitude 656, overshoot 658, and crossing point 660 as referenced herein may be the signals or modules of the DCA 652. The computer 662 may comprise any type system configured to execute one or more algorithms or processing on the values from the DCA 652. A graphical user interface may be displayed by the computer 662 to accept user controllable values and features thus providing an interface between the computer / software and the user. In one embodiment, three different parameters for each channel are adjusted to standardize or make uniform across each channel the overshoot and then other characteristics of the eye diagram, while concurrently minimizing the bias current. In one embodiment, the parameters that are adjusted by the computer interface include bias current and modulation amplitude and crossing of eye diagram in any type of optical transmitters by using DCA. It is contemplated that the computer 662 may execute machine readable code, commonly referred to software, on a processor to generate control data or error signals that are fed back to the microprocessor 604.

[0038] The computer interface 662 analysis the data from the DCA to optimize the eye diagram corresponding to the optic signal 616 to maximize the eye opening. In one embodiment the overshoot is set to a uniform amount or percentage for each channel, e.g. the signal on each channel is adjusted to have the same overshoot or percentage overshoot. In one example embodiment the overshoot percentage is 20% of Vamp but it is contemplated that other percentage values may be used. In one embodiment, this occurs in connection with a minimizing of the bias current. Minimizing the bias current has several advantages. One such advantage is reduced power consumption, which in turn also leads to reduced heat generation. Increased heat in one driver circuit and light source will affect the performance of the other drivers and light sources in the module, thereby degrading performance of not only the driver/light source with high temperature (caused by the high bias current) but also other drivers/light sources in the optic module. Temperature can also cause wavelength drift, thereby degrading performance, and lead to increased failure rate over time.

[0039] The output of the computer interface 662 is provided to the microprocessor 604 and the resulting optimized settings are stored in the memory 624 that is in communication with the microprocessor. In one embodiment, the signal from the computer interface 662 to the microprocessor comprises error signals, that the microprocessor analyzes and processes to determine the modulation signal and bias signals that make the overshoot uniform across all channels which in turn allows for optimization of the eye diagram across all channels. To control the overshoot, the bias current can be adjusted as can the extinction ratio (which relates to the modulation current). The extinction ratio is defined as the ratio of Vtop to Vbottom.

[0040] For example, the computer interface 662 may use PID (proportional integral derivative) control to communicate and provide the error values between actual signal values and target values, or other control values, to the microprocessor 604 so that the microprocessor can control the modulation current and bias current to achieve optimized eye diagram. A proportional-integral-derivative controller (PID controller) is a control loop feedback mechanism widely used in control systems and a variety of other applications requiring continuously modulated control. A PID controller continuously calculates an error value as the difference between a desired setpoint (target) and a measured variable (signal magnitude/peak) and applies a correction based on proportional, integral, and derivative terms (denoted P, I, and D respectively). In practical terms it automatically applies accurate and responsive correction to a control function. PID control is generally understood by one of ordinary skill in the art and as a result it is not described in detail here. In one embodiment, this is referred to as error tracking. In other embodiments, other data is sent from the test and optimization module 620 to make the overshoot uniform across channels and optimize the eye diagram.

[0041] Upon receiving the error values and adjusting the output from the microprocessor 604 to the light source driver 608 to make uniform and optimize the optic signal on each channel, the microprocessor also stores the values in the memory 624. These optimized settings, which are stored in the memory 624, are usable during operation once connected for data communication (after the text and configuration phase). In one embodiment, numerous optimized settings are created and stored in memory to account for different operating environments, such as high power and low power operation, various power settings, operation over various temperatures, operating over aging of the light sources, and operating center of wavelength in each band or any other parameter. Then during operation, as the parameters change, the processor will recall the settings from memory to control light source driver operation, and such control will enact optimal signal settings to optimize the eye diagram due to the uniform overshoot across channels. For example, it is understood that the eye diagram can change over temperature but this innovation stores optimized settings that optimizes the signal to thereby optimize the eye diagram over various temperatures, and these optimizes settings, for different temperatures are stored in the memory 624. Stated another way, this innovation optimizes the EMM (eye mask margin) over temperature. This optimization also minimizes bias current. [0042] Also shown in Figure 6 are two optional features that may optionally be utilized with the innovation. These features are a signal detection module 670 and a power control module 674. The signal detection module 670 includes a photodetector configured to receive the optic signal and convert the optic signal to an electrical signal. The output of the photodetector is provided to a signal converter, such as an transimpedance amplifier. The output of the signal converter is provided to a RMS unit as shown, and to the power control module 674. The RMS unit derives the peak to peak values of the signal, and provides the output to the power control module 674.

[0043] The power control module 674 includes an automatic power control (APC) unit and an automatic extinction ratio control (AEC) unit. The APC and AEC units receive the output from the feedback module and provide power control and extinction ratio control signals to summing the summing junctions to thus control the bias current and modulation current. This may occur in real time during operation to maintain desired optic signal power.

[0044] One example environment of use is in an optic communication system that utilizes optical fiber links and lasers or some other form of optic signal generator (light source). Figure 7 illustrates an exemplary optic fiber communication link. To enable communication between remote networking equipment 704A, 704B a fiber optic transmitter and receiver is provided. Laser drivers 712, part of a transmitter 708, drive the lasers 716 with a modulating current which produces modulating optical output from lasers. This optical output is coupled into the optical fiber 720 for signal transmission. At the receive side of the optical fiber link is a receiver 728. Optical energy is converted into electrical signals by a photodiode 732 and processed further by an amplifier 736 to set the signal magnitude to a level suitable for further processing. It is contemplated that the innovation disclosed herein may be used in other environments.

Claims

CLAIMS What is claimed is:

1. A method for automated tuning of an optic signal toward uniformity across channels comprising:

providing an eye diagram optimization system and an optic module having a first channel optic system, configured to generate a first optic signal, and a second channel optic system configured to generate a second optic signal;

establishing start settings for first channel optic system;

generating a first channel optic signal with the first channel optic system; establishing overshoot for the first channel optic signal as a percentage of voltage amplitude;

establishing overshoot for the second channel optic signal as a percentage of voltage amplitude;

maximizing an eye mask margin for the first channel optic signal while minimizing bias voltage to reduce heat generation;

maximizing an eye mask margin for the second channel optic signal while minimizing bias voltage to reduce heat generation;

tuning each channel to achieve a uniform eye diagram for the first channel optic signal and the second channel optic signal; and

storing the settings in a memory associated with the optic module.

2. The method of claim 1 further comprising a third channel optic system and a fourth channel optic system.

3. The method of claim 1 wherein the settings include: bias voltage, modulation voltage, and crossing voltage.

4. The method of claim 1 wherein the percentage of voltage amplitude is between 15% and 25%.

5. The method of claim 1 further comprising repeating the turning at different temperatures to generate settings for different temperatures and storing the settings for different temperatures in the memory.

6. The method of claim 1 wherein the eye diagram optimization system monitors average optical power, eye amplitude, overshoot and crossing point.

7. The method of claim 1 wherein the optic module further comprises:

a signal detection module configured to convert the first channel optic signal to an electrical signal to generate one or more feedback signals; and

a power control module configured to receive and process the feedback signal and provide power control and extinction ratio control feedback signal for optic module.

8. A system for optimizing settings of a multichannel optic module comprising: a memory configured to store optic module settings;

a processor configured to access the stored optic module settings and implement the settings in the optic module;

one or more light sources, each configured to generate an optic signal based on the input signal and the settings;

an optimization module configured to receive and analyze the one or more optic signals, the analyzing including optic power, eye amplitude, overshoot and responsive to the analyzing generating the settings by:

setting the overshoot to a target overshoot value for all channels;

optimizing eye mask margin in the one or more optic signals while minimizing bias voltage;

at different temperatures, generate resulting bias voltage, modulation voltage and crossing voltage for different temperature to form optic module data across temperature; and

storing the optic module data across temperature in the optic module.

9. The system of claim 8 wherein the target overshoot value is 20% of voltage amplitude.

10. The system of claim 8 wherein setting the overshoot to a target overshoot value for all channels comprises adjusting bias voltage, modulation voltage, and crossing voltage.

11. The system of claim 8 wherein bias voltage is minimized to reduce optic module heating.

12. The system of claim 8 wherein the optic module further comprising a signal detection module and a power control module.

13. The system of claim 12 wherein the signal detection module includes a photodetector and a peak detector, the photodetector is configured to convert an optic signal to an electrical signal and the detector

14. The system of claim 13 wherein the power control module includes an automatic power control unit and an automatic extinction ratio control unit configured to provide power control and extinction ratio control, which in turn controls bias current and modulation current.

15. A method for establishing the settings in a multichannel optic module comprising:

connecting the optic module to an optimization module

establishing initial settings in the multichannel optic module for each channel, the settings including bias voltage, modulation voltage, and crossing voltage;

setting the overshoot to a target overshoot value for each channel;

adjusting the settings to optimize the eye mask margin and minimize bias voltage;

generate the settings at different temperatures to create settings across temperature; and

storing the settings across temperature in a memory of the optic module.

16. The method of claim 15 wherein the optimization module analyzes an eye diagram created by optic signal from the multichannel optic module and uses PID control determine optimal setting for the multichannel optic module.

17. The method of claim 15 wherein the target overshoot value is 20% of voltage amplitude.

18. The method of claim 15 wherein setting the overshoot occurs in real time mode and performing eye diagram analysis occurs based on signal analysis on signals accumulated over time.

19. The method of claim 15 wherein setting overshoot occurs using a PID control loop.

20. The method of claim 15 further comprising fine tuning the settings to make the eye diagram for each channel uniform.