CN101147342A

CN101147342A - Controlling loss of signal thresholds in an optical receiver

Info

Publication number: CN101147342A
Application number: CNA2006800091470A
Authority: CN
Inventors: 斯蒂芬·T·尼尔森
Original assignee: Finisar Corp
Current assignee: Finisar Corp
Priority date: 2005-03-22
Filing date: 2006-03-22
Publication date: 2008-03-19

Abstract

Systems and methods for programming a loss of signal (''LOS'') threshold level relating to the receipt of optical signals by an optical receiver are disclosed. By the present invention, the LOS threshold level can be dynamically programmed and adjusted during operation of the optical receiver according to the data rate of the received optical signal. This in turn provides improved optical signal reception characteristics for the receiver. In one embodiment, an optical receiver system having a programmable LOS threshold level is disclosed, comprising an optical receiver that receives an optical signal, a photodetector that senses receive power of the optical signal, a memory location containing a plurality of programmed LOS threshold levels, a processor that selects one of the programmed LOS threshold levels according to an input signal received by the processor, and a comparator that compares the optical signal receive power with the programmed LOS threshold levels.

Description

Loss of signal thresholds in the control optical receiver

Technical field

Present invention relates in general to optical receiver, as the optical receiver that exists in the optical transceiver module.In particular, the present invention relates to a kind of optical receiver, this optical receiver can dynamically arrange and adjust the loss of signal thresholds level according to the data rate of the light signal that it received.

Background technology

In the light data transmission network, define the light signal receiving sensitivity specification of optical receiver according to the data rate of light signal, at given physical interface specification such as optical-fibre channel (" FC "), gigabit Ethernet (" GbE ").Like this, can determine when the received power of the light signal that optical receiver received drops to below the acceptable parameter according to particular sensitivity specification.When such situation took place, optical receiver can send " loss of signal " (" LOS ") but alarm is notified with the host computer system that is connected to optical receiver to the place of working: the relative intensity of institute's receiving optical signals made the correct transmission that is included in the data in the light signal to be interrupted.If receive such alarm, so then host computer system can start trimming process and corrects this situation of problem.

In optical network data transmission activities, host computer system can be come receiving optical signals with a plurality of transfer of data frequencies or data rate by optical receiver.The example of such data rate comprises 1,2,4,8 or even 10 gigabits (" Gbit ")/second.The light signal that receives with specific data rate is typically distributed a threshold level, is lower than this threshold level, and optical receiver will send the LOS alarm and indicate the low excessively received power of this signal.For example, according to particular sensitivity specification, light signal with data rate of 1 gigabit/sec can be assigned with the LOS threshold level of pact-20dB, signal with the data rate transport of 4 gigabit/sec can have-the LOS threshold level of 15dB, and the signal with data rate of 8 gigabit/sec can have-the LOS threshold level of 12dB.Therefore, (for below approximately-15dB), then optical receiver will send the LOS alarm to host computer system in the case if the received power of the light signal of 4 gigabit/sec drops to its LOS threshold value.

The optical receiver that adopts in many optical receivers such as the optical transceiver module adopts the based on multiple data rates technology at present, and wherein receiver can adapt to the reception of the light signal with different respectively data rates.Yet such module typically can limit only LOS threshold level by Default Value.This may not conform to and desirably causes too early or too lately warning host computer system by the LOS alarm for the light signal with not enough received power.

In view of above problem, need a kind of optical receiver in the art, this optical receiver can adapt to the reception of the light signal with different pieces of information speed and can dynamically adjust the LOS threshold level according to the corresponding light signal, thereby provides alarm timely so that keep the suitable received power level of light signal to host computer system.In particular, any scheme should be able to adapt to the light signal with data rate (comprising 8 and 10 gigabit/sec) current use or the raising that prediction will be adopted in the future.In addition, any scheme should allow the level of sensitivity place of transceiver module or near distribution LOS alarm levels so that prevent from too early or too lately to warn the LOS situation.

Summary of the invention

Made the present invention in response to above-mentioned and other demand in this area.In brief, all embodiment of the present invention relate to the system and method that is used for dynamically adjusting the relevant loss of signal (" the LOS ") threshold level of the light signal that received with optical receiver.The dynamic LOS threshold value adjustment that the present invention realized adapts to the optical receiver that adopts in the enforcement that can receive a plurality of light signals with different pieces of information speed.This has guaranteed again during the optical receiver receiving optical signals, and the received power of light signal suitably is associated with corresponding LOS threshold level.

In one embodiment, disclose a kind of optical receiver system with LOS threshold level able to programme, this system comprises: optical receiver, receiving optical signals; Photoelectric detector, the received power of sensor light signal; Memory location comprises a plurality of LOS of being programmed threshold levels; Processor selects to be programmed in the LOS threshold level one according to the input signal that this processor received; And comparator, with the light signal received power be programmed the LOS threshold level and compare.

In another embodiment, disclose a kind of optical receiver system with programmable loss of signal threshold level, this system comprises: optical receiver, receiving optical signals; Photoelectric detector, the received power of sensor light signal; Control module, comprise register and processor the two, wherein register comprises a plurality of loss of signal thresholds settings that are programmed.Processor comprises microcode, this microcode makes processor operate below carrying out when being performed: in response to the input signal relevant with the data rate of light signal, from register, select a plurality of loss of signal thresholds in being provided with, and selected loss of signal thresholds setting is forwarded to comparator, comparator compares the light signal received power of selected loss of signal thresholds setting and institute's sensing.

In another embodiment, a kind of method that the relevant loss of signal indication of the light signal that received with optical transceiver module is provided is disclosed, this method comprises: visit the input signal relevant with the data rate of light signal, according to data rate allocation loss of signal thresholds level, the received power of light signal is compared to determine whether to exist loss of signal situation with the loss of signal thresholds level of being distributed, if there is loss of signal situation, then loss of signal alarm is sent to host computer system.

These and other feature of the present invention will become more obvious according to following description and claims, perhaps can come known to practice of the present invention by what hereinafter set forth.

Description of drawings

In order further to illustrate above-mentioned and other advantage and feature of the present invention, will come the present invention is described more specifically with reference to illustrated specific embodiment of the present invention in the accompanying drawings.Should be appreciated that these accompanying drawings have only been described exemplary embodiments of the present invention, therefore should not be considered as scope of the present invention is construed as limiting.Will by use accompanying drawing more specifically, describe and explain the present invention in detail, in the accompanying drawings:

Fig. 1 is the perspective view of the optical transceiver module of all embodiment configurations according to the present invention;

Fig. 2 is the simplified block diagram of each side that the optical transceiver module of Fig. 1 is shown;

Fig. 3 is the simplified block diagram that is included in the integrated circuit control module in the optical transceiver module shown in Figure 2;

Fig. 4 is the simplified block diagram of the optical transceiver module of Fig. 2, and each parts of LOS distribution system according to an embodiment of the invention are shown;

Fig. 5 A is the simplified block diagram that comprises according to each parts of the LOS distribution system of another embodiment;

Fig. 5 B is the simplified block diagram according to the part of the LOS distribution system of another embodiment;

Fig. 6 is the simplified block diagram that comprises according to each parts of the LOS distribution system of an embodiment;

Fig. 7 is the simplified block diagram that comprises according to each parts of the LOS distribution system of another embodiment.

Embodiment

With reference now to accompanying drawing,, wherein identical structure will be provided with identical Reference numeral.Should be understood that accompanying drawing is the expression of the graphic of example embodiment of the present invention and signal, neither the present invention is construed as limiting, also not necessarily draw in proportion.

Fig. 1-6 has described the various features of all embodiment of the present invention, and it relates generally to the system and method that is used for dynamically adjusting the relevant loss of signal thresholds level of the light signal that received with optical receiver.This makes that again the LOS threshold level can be suitably relevant with the data rate of institute receiving optical signals, and this data rate can receive operating period at the signal of optical receiver to be changed in time.

In this example embodiment, optical receiver is implemented as the receiver photonic component (" ROSA ") of optical transceiver module (" transceiver ").ROSA together with the reflector photonic component (" TOSA ") of transceiver but comprise each parts that makes it possible to be connected to the host computer system receiving optical signals of transceiver from the place of working and send light signal to this host computer system.This host computer system can be used as a node and for example is included in the optical communication network, and can adopt transceiver other components communicate by light signal and this network.Yet, should not be construed as about the discussion of all embodiment of the present invention that relate to the LOS threshold value in the dynamic adjustment transceiver below it should be noted that and limit the invention to only such embodiment.In fact, should be understood that the principle of the invention can also expand to the optical receiver that adopts in other configuration.

1. demonstration work environment

At first with reference to figure 1, but Fig. 1 described generally by 100 expressions, be used for sending and the perspective view of the optical transceiver module (" transceiver ") of receiving optical signals in conjunction with the external host that place of working in one embodiment is connected to the communication network (not shown).As depicted, transceiver shown in Figure 1 comprises each parts, and these parts comprise: the optical receiver, reflector photonic component (" TOSA ") 20, electrical interface 30, each electronic unit 40 and the printed circuit board (PCB) 50 that are implemented as receiver photonic component (" ROSA ") 10.At length, two electrical interfaces 30 are included in the transceiver 100, are respectively applied for ROSA 10 and TOSA 20 are electrically connected to a plurality of conductive pads that are positioned on the PCB 50.But electronic unit 40 also place of working is attached to PCB50.Edge connector 60 is positioned on the end of PCB50, so that transceiver 100 can dock with main frame (not shown here) electricity.Like this, the PCB50 facility electric connection between ROSA 10/TOSA20 and the main frame.In addition, the above-mentioned parts of transceiver 100 partly are contained in the housing parts 70.Though not shown, outer cover can be worked in coordination with the covering of the parts that limit transceiver 100 with housing parts 70.

With reference now to Fig. 2,, Fig. 2 is the simplified block diagram of the transceiver 100 of Fig. 1, has described each physics and aspect work of transceiver 100.Although will describe in detail optical transceiver 100, also only optical transceiver 100 is described by diagram rather than by limiting the scope of the invention.As mentioned above, the optical transceiver 100 among embodiment be suitable for multiple per second data rate (comprising 1,2,4,8,10 gigabits) or more the high bandwidth optic fibre link carry out light signal and send and receive.In addition, the principle of the invention can be implemented with the optical transceiver of the Any shape factor (as XFP, SFP and SFF, being not limited in this respect).

At work, optical transceiver 100 passes through ROSA 10 from optical fiber 110A receiving optical signals in the mode that below will describe more comprehensively.ROSA 10 serves as light electric transducer by converting receiving optical signals to the signal of telecommunication.ROSA 10 offers post amplifier with the resulting signal of telecommunication.In illustrated embodiment, post amplifier and laser driver are merged into integrated post amplifier/laser driver (" PA/LD ") 102.Like this, PA/LD 102 is positioned on the single integrated circuit chip, and is included on the printed circuit board (PCB) (" PCB ") 50 together with other electronic unit 40 (wherein some are further described below) as parts.About the further details of integrated PA/LD 102 can whole by reference be incorporated into this, be filed on October 21st, 2004, title is the U.S. Patent application No.10/970 of " Integrated Post Amplifier; Laser Driver; and Controller ", find in 529 (" 529 applications ").In other embodiments, post amplifier and laser driver can be used as separated components and are included on the PCB 50.

The post amplifier part amplification signal of PA/LD 102 also offers external host 111 with amplifying signal, shown in arrow 102A.External host 111 can be any computing system that can communicate by letter with optical transceiver 100.External host 111 can comprise mainframe memory 112, and this memory can be volatibility or source of non-volatile memory.In one embodiment, some parts of optical transceiver 100 can be positioned on the main frame 111, and other parts of optical transceiver 100 are positioned on the printed circuit board (PCB) 50 that separates with main frame.

Optical transceiver 100 can also receive the signal of telecommunication from host computer system 111, so that send on the optical fiber 110B.Particularly, the laser driver of PA/LD102 partly receives the signal of telecommunication, shown in arrow 102B, and the laser in the TOSA 20, the information in the signal of telecommunication that described light signal is represented to be provided by main frame 111 are provided the signal that makes TOSA send light signal on optical fiber 110B.Therefore, serve as electro-optic transducer with the corresponding TOSA 20 of the TOSA shown in Figure 1B.

The behavior of ROSA 10, PA/LD 102 and TOSA 20 may dynamically change owing to some factors.For example, variations in temperature, power fluctuation and feedback conditions may all can influence the performance of these parts.Therefore, transceiver 100 comprises control module 105, but control module 105 Evaluation Environment situations such as temperature and/or working condition such as voltage, and partly receive information (shown in arrow 105A) and partly receive information (shown in arrow 105B) from the laser driver of PA/LD 102 from the post amplifier of PA/LD 102.This allows control module 105 to optimize the performance of dynamic change, also detects when there is the loss of signal in addition, and this will be described in greater detail below.Control module 105, post amplifier 102 and laser driver 103 can be same chips, as disclosed in ' 529 applications.Alternatively, they can be striden two or more chips and distribute on PCB 50.

Particularly, control module 105 can be by adjusting the work of optimizing transceiver 100 that is provided with on the PA/LD102, shown in arrow 105A and 105B.These are provided with adjustment can be intermittent and carry out when temperature or voltage or other low frequency variations have adequate cause, perhaps can carry out termly according to predetermined pattern.

Control module 105 can be visited permanent memory 106, and in one embodiment, permanent memory 106 is electric erasable and programmable read only memory (" EEPROM ").Permanent memory 106 can also be any other source of non-volatile memory.Permanent memory 106 can be encapsulated in the same encapsulation together with control module 105 or in the different encapsulation, be not limited in this respect.

Can use serial time clock line SCL and serial data line SDA that data and clock signal are offered control module 105 from host computer system 111.Can also use serial data signal SDA that data are offered host computer system 111 from control module 105, to allow to send diagnostic data such as environment and/or running parameter.Control module 105 comprises simulation part 108 and numerical portion 109.These two parts allow control module digitally to implement logic altogether, still mainly use analog signal to dock with the remainder of optical transceiver 100 simultaneously.

As used herein like that, term " diagnostic data " refer to environmental parameter and running parameter the two, no matter this parameter still is treated data and providing as initial data.Diagnostic data can provide with the analog or digital form.Environmental parameter can be that for example supply voltage, humidity, acceleration, ambient light level, ambient vibration, magnetic flux intensity or any other may influence the performance of photoelectric device and the environmental parameter that can compensate by the suitable adjustment to one or more running parameters.Environmental parameter also can be irrelevant with the work of photoelectric device, but may influence running parameter.Running parameter can comprise statistical information, for example the sum of net cycle time, the average operation time between starting, the erroneous condition that run into, to the sign of one or more erroneous condition of being run into, at multiple different type of errors to the classification of the number of the erroneous condition that run into, start the number of times etc. of optical transceiver.Running parameter for example comprises also that optical maser wavelength is approximate, laser temperature measured value, supply voltage measured value, transceiver temperature measured value, laser bias current measured value, thermoelectric (al) cooler (" TEC ") current measurement value, transmitted power measured value, received power measured value, acceleration measurement, peak accelerator measured value etc.

Fig. 3 has schematically shown the example configuration 200 of control module 105 in more detail.Control module 200 comprises the numerical portion 200B of example of the numerical portion 109 of the simulation part 200A of example of simulation part 108 of presentation graphs 2 and presentation graphs 2.For example, simulation part 200A can comprise digital to analog converter, analog to digital converter, (for example being used for event detection) high-speed comparator, the reseting generator based on voltage, voltage regulator, voltage reference, clock generator and other analog component (generally by 215 expressions).For example, the simulation part branch comprises

transducer

211A, 211B, 211C, also may comprise other transducer of being represented by horizontal ellipses 211D.In these transducers each can be responsible for measuring can be from the environment and/or the running parameter of control module 200 measurements, for example supply voltage and transceiver temperature.Control module can also receive external analog or digital signal from other parts in the optical transceiver.Illustrate two the outer lines 212A and the 212B that are used to receive such external analog signal, although may there be many such lines.

Internal sensor 211A-211D can produce the analog signal of expression measured value.In addition, the signal 212A, the 212B that provide of outside can also be analog signal.In this case, it is used so that can be the numerical portion 200B of control module 200 that analog signal is converted into digital signal, so that further handle.Certainly, each analog parameter value can have its oneself analog to digital converter (" ADC ").Yet,, can use single ADC ADC 214 each signal of periodic sampling in a looping fashion as illustrated in order to keep chip space.In this case, each analogue value can be provided for multiplexer 213, and multiplexer 213 is selected in the analog signal in a looping fashion so that sampled by ADC214 at every turn.Alternatively, multiplexer 213 can be programmed to allow the analog signal sampling of 214 pairs of any magnitudes of ADC.

As mentioned above, the simulation part 200A of control module 200 also comprises other analog component 215, for example digital to analog converter, other analog to digital converter, (for example being used for event detection) high-speed comparator, the reseting generator based on voltage, voltage regulator, voltage reference, clock generator and other analog component.High-speed comparator can be provided with from internal sensor or from an input of outer lines, to receive measured parameter value.Another input to comparator can be a comparison value.If measured parameter value surpasses comparison value, then comparator can produce the logic high (or low) that this incident of indication has taken place.For example, suppose that the standard maximum transceiver temperature is 85 degrees centigrade.The transceiver temperature of actual measurement can be offered comparator as an input, and will represent that 85 degrees centigrade value offers another input of comparator.Like this, can execution parameter compare.

Also comprise general processor 203A.The instruction of particular, instruction set is obeyed in the identification of this processor, and carries out common general-purpose operation, as displacement, branch, add, subtract, multiplication and division, Boolean calculation, comparison operation etc.In one embodiment, general processor 203A is 16 bit processors and can constructs in the same manner.The precision architecture of instruction set is inessential for the principle of the invention, and this is because can optimize instruction set according to the specific hardware environment, also because accurately hardware environment is inessential for the principle of the invention.

Host communication interface 204 is used to use the serial data (" SDA ") of optical transceiver 100 to communicate by letter with main frame 111 with serial clock (" SCL ") line and serial data line SDA.External apparatus interface 205 for example be used to optical transceiver 100 in other module (for example post amplifier/laser driver 102 or permanent memory 106) communicate.

Internal controller system storage 206 (not obscuring with external persistent memory 106) can be random access memory (" RAM ") or nonvolatile memory.Memory Controller 207 and processor 203A, host communication interface 204 and external apparatus interface 205 shared visits to controller system memory 206.

In one embodiment, host communication interface 204 comprises serial interface controller 201A, and external apparatus interface 205 comprises serial interface controller 201B.This dual serial interface controller 201A and 201B can use two-wire-interface such as I ²C communicates by letter, and perhaps can be another kind of serial line interface, as long as this interface is discerned by two communication modules.A serial interface controller (for example serial interface controller 201B) is a master unit, and another serial interface controller (for example serial interface controller 201A) is from parts.

I/O multiplexer 208 is with each I/O pin multiplexing of control module 200 each parts to the control module 200.This makes different parts to come the dynamic assignment pin according to the operational environment that existed at that time of control module 200.Therefore, the I/O node in the control module 200 may be more than pin available on the control module 200, thereby reduced the footprints (footprint) of control module 200.

Described specific environment at Fig. 1-3, should be understood that this specific environment only is one that wherein can adopt in the countless architectures of the principle of the invention.As mentioned above, the principle of the invention is not intended to be limited to any specific environment.

Referring to figs. 2 and 3, carry out the microcode that receives from the source as the control module 200 that the demonstration of control module shown in Figure 2 105 is implemented.Particularly, processor 203A will be loaded into from the microcode in this source in the controller system memory 206.System storage can be RAM, yet it also can be processor, register, trigger or other memory device.For example, processor 203 can be loaded into the microcode that is stored in the permanent memory 106 in the controller system memory 206.Can comprise that from the microcode of permanent memory 106 indication will measure the function of which running parameter.Alternatively, microcode can be provided by external host 111, is passed to control module 105 by serial data line SDA.For example, external host memory 112 can comprise the storehouse of different microcode functions.Therefore the user can dock with main frame 111, and selects to move which microcode functions based on the expectation parameter that will measure.In addition, external host 111 can be connected to internet or certain other wide area network, thereby allows processor 203A to obtain microcode from remote source.This connection can realize by any standard the Internet or wan protocol.2. dynamic loss of signal threshold adjustment

Together with Fig. 1-3, with reference now to Fig. 4.Generally speaking, the above-mentioned operational environment that comprises transceiver 100 has been demonstrated and can have been put into practice an environment of the principle of the invention.In particular, all embodiment of the present invention make it possible in response to the data rate of the variation of the light signal that ROSA 10 received of the transceiver in optical receiver such as the present embodiment 100 and dynamic programming are carried out in the loss of signal (" LOS ") threshold value setting.This makes optical receiver suitable LOS threshold value setting suitably can be associated with the current data speed of light signal, thereby makes the LOS alarm signal to be forwarded to main frame under the appropriate conditions relevant with loss of signal event.Accordingly, this has prevented to send the LOS warning owing to LOS threshold value static state, Default Value the setting in the known optical receiver too early or lingeringly to main frame.

In brief, standard body such as T11 and IAAA are the light signal reception specified sensitivity specification of optical receiver according to the particular physical interface specification that comprises FC and GbE physical interface.These sensitivity specification can be used to limit the setting of expectation LOS threshold value according to the specific data rate of institute's receiving optical signals.Therefore, the LOS threshold value represents to be considered to the minimum power level of institute's receiving optical signals enough for the use of the reception of optical receiver and host computer system.If the received power level drops to below the LOS threshold value, then run into the situation that is called the loss of signal (" LOS ").Under such situation, can produce signal warns main frame to have the LOS situation, the power level of indication institute receiving optical signals is lower than the threshold value of carrying out the acceptable standard of correct optical communication, institute's receiving optical signals is returned to the suitable power level parameter that is used to recover correct optical communication thereby make main frame can carry out trimming process.

As described, the different LOS threshold level of light signal needs that has different pieces of information speed.This is significant, because optical receiver usually is configured to receive a kind of light signal that has in the several data speed (as 1,2,4,8 or 10 gigabit/sec).Therefore, along with the data rate change of the light signal that transceiver received, the LOS threshold level also should conform with desirably change, so that provide institute's receiving optical signals whether to have the accurate indication of power level enough for enough optical communications.Like this, according to one embodiment of present invention, the transceiver 100 of the Xiang Shuing specific data rate that is configured to make it possible to according to institute's receiving optical signals is carried out adjustment able to programme at the optical receiver duration of work to the LOS threshold level here.

Fig. 4 show according to an embodiment, that make it possible to optical receiver is programmed as the LOS threshold value setting that is included in the ROSA 10 in the transceiver 100, generally by 400 the expression the LOS distribution systems.In detail, LOS distribution system 400 comprises each parts, and these parts are configured to or the transceiver 100 described in conjunction with Fig. 2 and Fig. 3 in conjunction with each front and/or the parts of control module 200, and this will see below.

LOS distribution system 400 at first comprises LOS table 402, and LOS table 402 comprises and is used to store a plurality of memory locations such as the register that relevant data are set with the LOS threshold value.In particular, LOS table 402 comprises rate selection part 404 and threshold setting portion 406.Rate selection part 404 comprises the relevant data of possible data speed with the light signal for the treatment of to be received by ROSA 10.In particular, in the present embodiment, two values of rate selection part 404 storages: indicate the logical zero of relatively low (" low ") data rate, indicate the logical one of higher relatively (" height ") data rate.Threshold setting portion 406 storage respectively with the low and corresponding threshold value of the high data rate value of setting that is stored in the rate selection part 404.As shown in the figure, threshold setting portion 406 is for threshold value value of setting of low data rate storage-20dB, for threshold value value of setting of high data rate storage-15dB.Therefore the value that is stored in the threshold setting portion 406 is provided with relevant with treat the expectation threshold value of distributing when whether definite light signal with low or high data rate that is received for ROSA 10 exists the LOS situation.

LOS table 402 among embodiment is included among the numerical portion 200B of control module 200, as shown in Figure 3 as a register in the registers group 209.In other embodiments, LOS table may reside in the controller system memory 206 of control module 200 or is present in another suitable position of this control module.

The value that is stored in the LOS table 402 can be preset when control module is made, perhaps can be by the programming after making of acceptable register/system storage programmed method.Main frame 111 in the present embodiment will be used for selecting the instruction of the high or low data rate clauses and subclauses of rate selection part 404 to offer processor 203A by limited rate selection pin interface of MSA and the sda line institute input signals transmitted that is present between main frame and the control module 200, and processor 203A selects data rates from the rate selection part 404 of LOS table 402.Other possible host computer control module interface comprises I ²The C line.

In case processor 203A selects part 404 to select data rate (promptly low or high data rate) according to host command from LOS indicated airspeed rate, in one embodiment, the holding wire of representing by external apparatus interface 205 with by 105A or 105B with the setting of the corresponding corresponding LOS threshold value of selected data speed is forwarded to LOS from the threshold setting portion 406 of LOS table 402 register 408 is set, and LOS is provided with register 408 these values of storage for comparator 412 uses.As the situation of many communications of carrying out between control module 200 and PA/LD 102, the LOS threshold value is provided with to convert to from the digital value being stored in LOS table 402 and is suitable for by LOS the analog signal that register 408 receives being set.This conversion can be realized by the digital to analog converter that is positioned at control module 200, PA/LD102 or transceiver 100 other correct positions.

In the present embodiment, LOS is provided with the post amplifier part 102A that register 408 is arranged in PA/LD 102, as comparator 412.Comparator 412 receive LOS be provided with LOS threshold value setting that register 408 the stored input signal relevant with the received power of the light signal that is received with the photoelectric detector 409 of ROSA 10 the two as input.In the present embodiment, photoelectric detector 409 is photodiodes, but and the input signal relevant with received power provide by the resistor 410 that is communicated with the photodiode place of working.

In brief, photoelectric detector light signal that photoelectric detector 409 is received converts to and the proportional current signal of the received power of light signal.The current signal that resistor 410 is used to receive from photoelectric detector 409 converts voltage signal to.This voltage signal is fed in the comparator 412 as an input then, corresponding voltage signal is set is fed in this comparator as second input and with LOS LOS threshold value that register 408 stored is set.The comparative result of these two inputs allows the received power of comparator 412 definite light signals to be higher than or is lower than the setting of LOS threshold value.

If the light signal received power is lower than the setting of LOS threshold value, then comparator 412 is forwarded to main frame 111 with the LOS alarm signal by holding wire or other the suitable communication interface of being represented by 103A.In one embodiment, the LOS alarm signal is the digital high voltage signal, and it conforms with pilot light signal received power, and desirably to be higher than the digital low voltage signal that the LOS threshold value is provided with relative.In one embodiment, comparator 412 provides continuous signal to main frame 112, indicates the digital high or low signal during its comparison.In another embodiment, comparator 412 can be configured to only just send signal when running into los state.

Should be understood that except the content of having discussed processor 203A also can relate to the one or more execution in the above-mentioned steps.And, though embodiment discussed here pays close attention to and uses analog comparator to determine when to have los state, in another embodiment, can digitally carry out this process.For example, analog to digital converter can relevant analog signal conversion become digital signal with the intensity level that is received with photoelectric detector.Processor can compare this digital signal and the threshold level that is stored in the special register group in system or the permanent memory or control module then, to determine where to exist los state.Therefore, this process can be implemented in many ways.

With reference now to Fig. 5 A,, Fig. 5 A described about according to a part another example embodiment, that be configured to transceiver 100, generally by each details of LOS distribution systems of 500 expressions.Before going through this embodiment, it should be noted that each parts is shared by this embodiment discussed here and other embodiment.Like this, will the selected feature of present embodiment only be discussed.However, some this embodiment or disclosed features of any other embodiment at here also can be applicable to other embodiment.

As previous embodiments, LOS distribution system 500 comprises the LOS table 502 as register in the numerical portion 200B of control module 200.This LOS table further comprises data rate part 504 and threshold setting portion 506.Compare with previous embodiment, the expanded in size of LOS table 502 all has four clauses and subclauses in data rate part 504 and threshold setting portion 506.In particular, data rate part 504 comprises the value that four different possible data speed are correlated with, and ROSA 10 can receive the speed data that is included in the light signal with described data rate.For example, the value " 1 " in the data rate part can be represented the data rate of 1 gigabit/sec, " 2 " expression 2 gigabit/sec, " 4 " expression 4 gigabit/sec, " 8 " expression 8 gigabit/sec.Accordingly, threshold setting portion 506 for example comprises-20 ,-18 ,-15 ,-value of 10dBm, each the LOS threshold value setting in the data rate in the data rate part that is included in LOS table 502 is distributed in indication respectively.As previously mentioned, LOS table 502 can be included among one or more in the controller system memory 206 of control module numerical portion 200B or in the registers group 209.And in other embodiments, the size of LOS table can enlarge or be reduced to the data rate of any proper number that the ROSA 10 that adapts to transceiver 100 may run into.

Main frame 111 can utilize above-mentioned LOS table 502 to select to treat the proper data speed of the light signal that received by transceiver ROSA 10.In particular, in control module numerical portion 200B or other correct position in the transceiver 100 set up data rate register 514, and data rate register 514 is communicated by letter with main frame 111 by SDA holding wire or other appropriate signal line.Main frame 111 can be forwarded to data rate register 514 and distributes optical signal data speed by the input signal that will comprise the corresponding data rate value then.By processor 203A, consult the value that LOS table 502 determines to distribute to main frame 111 the relevant LOS threshold value setting of the value of data rate register 514.For example, in illustrated embodiment, main frame 111 will be worth " 4 " and distribute to data rate register 514, and indication treats that the data rate by the light signal of ROSA 10 receptions is 4 gigabit/sec.With reference to LOS table 502, indication this threshold level setting relevant with the data rate of 4 gigabit/sec seen in threshold setting portion 506-15dB.The control module LOS that in the manner described before this value is forwarded to PA/LD 102 is provided with register then, and is so that make comparator can determine whether to have the LOS situation for the received power of institute's receiving optical signals, such as explained.

Fig. 5 B has described in conjunction with Fig. 5 A and has described and the mutation of the embodiment that describes, and wherein main frame 111 not only can distribute the data-rate value of waiting to be retained in the data rate register 514, and can allocation packet be contained in the value in the LOS table 502.For example, shown in Fig. 5 B, main frame can be distributed to particular value and the corresponding threshold setting portion of the data rate of 2 gigabit/sec position as-17dB.

Notice that at transceiver 100 duration of works, the data rate of the light signal that ROSA 10 is received may change.In this case, main frame 111 can send to data rate register and/or LOS table 502 with newly being worth, to adapt to maybe other situation of needs value modification of new data rate.Be also noted that in one embodiment, an entity or a device that is different from main frame can be distributed to value data rate register or LOS table.In addition, should be understood that LOS shows and the value and the ad hoc structure of data rate register only are exemplary; Also can adopt other value and the register configuration that fall in the claim scope of the present invention.

With reference now to Fig. 6,, Fig. 6 shows transceiver 100 and the ROSA 10 that has according to the LOS distribution system of another example embodiment.In detail, Fig. 6 has described to dispose the transceiver 100 of the function of the data rate that makes transceiver can detect the light signal that ROSA 10 received, and this will be described below.

Similar with aforementioned all embodiment, LOS distribution system 600 comprises the LOS table 602 with data rate part 604 and threshold setting portion 606.Data rate register 604 also is included among the numerical portion 200B of control module 200 with above-mentioned parts.

In illustrated embodiment, frequency detector 616 is included among the post amplifier part 102A of PA/LD 102.But frequency detector 616 is attached to the trans-impedance amplifier (" TIA ") 618 of ROSA 10 by two differential signal line 620 places of working.But TIA 618 place of working again is connected to photoelectric detector 409 comprises the data of the light signal transmission that is received by ROSA 10 with generation electric differential signal.This differential signal sends to frequency detector 618 by holding wire 620, and frequency detector 618 analysis package data flow with which is to determine the data rate of institute's receiving optical signals.Alternatively, those skilled in the art can utilize other parts to come independently to determine the data rate of institute's receiving optical signals.Therefore, only the demonstrated frequency detection equipment that can adopt at transceiver 100 of certain limit of the frequency detector 616 that Fig. 6 described.

The data rate register 614 that the data-rate information that frequency detector 616 obtains at transceiver 100 duration of works is forwarded to control module 200 as input signal by the holding wire represented by 105A and 105B and external apparatus interface 205.Data rate register 614 is preserved data-rate value, makes processor 203A can use data rate part 604 and threshold setting portion 606 to consult LOS table 602 and determines suitable LOS threshold value setting.In case selected the suitable threshold setting, as previously mentioned, control module 200 is provided with register 408 with the LOS that selected setting is forwarded among the PA/LD 102, is used for determining whether to exist the LOS situation for comparator 412.

With top similar, should understand, data rate part that transceiver (transceiver as described above) with autonomous data rate detection function can further make the control module among the embodiment to revise to be included in the LOS table and the value in the threshold setting portion, this may be expectation or needs at the transceiver duration of work.Should be further understood that although transceiver carries out autonomous data rate detection, it still can be kept and the communicating by letter of main frame about the various situations relevant with the institute receiving optical signals.

The discussion that provides is above paid close attention to and is used all embodiment of the present invention to determine when to have the LOS situation.Yet, all embodiment of the present invention can be expanded to the opposite situation that comprises LOS, determine when that promptly existence indicates this state for the enough signal of transfer of data and by signal detection signal.Therefore, this that conceived is used and other other application falls in the claim scope of the present invention.

With reference now to Fig. 7,, another embodiment of the present invention is wherein disclosed.In other embodiments of the invention embodiment as shown in Figure 6, the absolute power measurement result of use reception light is determined the assessment to los state.Yet, in some systems such as fibre channel system, can adopt optical modulation amplitude (" OMA ") to determine los state in such system.Fig. 7 is configured to use the OMA data to detect the example of such system of los state.In this embodiment, as in the embodiment shown in fig. 6, from two differential signal lines 620 and frequency detector 616 interconnection of TIA 618.Yet other holding wire 625 diverges to and is fed to the comparator 412 with the holding wire that register 408 extensions are set from LOS from holding wire 620.Notice that two holding wires 625 have replaced 412 the holding wire from PD 409 to comparator among aforementioned all embodiment.Therefore, work comprises three inputs to comparator 412 according to OMA, so that can determine los state at fibre channel system.In another embodiment, answer attention line 625 directly to present from TIA618.

Under the situation that does not deviate from spirit of the present invention or essential feature, can implement the present invention with other particular form.Described embodiment only answers taken as illustrative in all respects, rather than restrictive.Therefore scope of the present invention limits by claims rather than by the description of front.Implication and all changes in the scope at the equivalent of claim should fall in the scope of claim.

Claims

1. one kind has the optical receiver system that the programmable signal dependent thresholds is provided with, and this optical receiver system comprises:

Optical receiver, receiving optical signals;

Photoelectric detector, the received power of the described light signal of sensing;

At least one memory location comprises a plurality of signal correction threshold value settings that are programmed;

Processor is selected described signal correction threshold value in being provided with that is programmed according to the input signal that described processor received; And

Comparator is with described light signal received power and describedly be programmed of selecting described in the setting of signal correction threshold value and compare.

2. optical receiver according to claim 1, the wherein said signal correction threshold value that is programmed is provided with a plurality of may input signal values corresponding, and all the data rate with described light signal is relevant for each in described a plurality of possible input signal values.

3. optical receiver according to claim 1, wherein said signal correction threshold value are provided with selection in following: loss of signal thresholds setting and signal detection threshold setting.

4. optical receiver according to claim 1, wherein said at least one memory location is made of nonvolatile memory.

5. optical receiver according to claim 1, wherein said optical receiver is included in the optical transceiver module, and wherein said comparator is included in the post amplifier part of described optical transceiver module.

6. optical receiver system with programmable loss of signal threshold level, this optical receiver comprises:

Optical receiver, receiving optical signals;

Photoelectric detector, the received power of the described light signal of sensing; And

Control module comprises:

At least one register comprises a plurality of loss of signal thresholds settings that are programmed; And processor, comprise the microcode that when carrying out, makes operation below the described processor execution:

In response to the input signal relevant with the data rate of described light signal, from register, select a plurality of loss of signal thresholds be provided with in of appointment; And

The loss of signal thresholds setting of described selection is forwarded to comparator, and described comparator compares the loss of signal thresholds setting of described selection with at least one signal relevant with described light signal.

7. optical receiver according to claim 6 system, wherein said at least one register comprises: the data rate part that comprises a plurality of possible data speed of described light signal; And the loss of signal thresholds that comprises described a plurality of loss of signal thresholds settings is provided with part.

8. optical receiver according to claim 7 system, further comprise the data rate register that is used for comprising the data-rate information that described input signal comprises, but described data rate register is communicated by letter with at least one place of working in described at least one register with described processor.

9. optical receiver according to claim 8 system can be revised by the host computer system that the place of working is connected to described optical receiver system but wherein be included in the information that described data rate part, described loss of signal thresholds be provided with in part and the described data rate register at least one.

10. optical receiver according to claim 6, wherein said input signal is produced by the frequency detector of the described data rate of determining described light signal, and described frequency detector is included in the described optical receiver system as parts.

11. optical receiver according to claim 6, wherein relevant with described light signal described at least one signal is selected in following: the optical modulation amplitude of the power of the light signal of described sensing and the light signal of described sensing.

12. a method that is used to provide the relevant loss of signal indication of the light signal that received with optical transceiver module, this method comprises:

Visit the input signal relevant with the data rate of described light signal;

Processor is according to described data rate allocation loss of signal thresholds level;

The received power of described light signal and the loss of signal thresholds level of described distribution are compared to determine whether to exist loss of signal situation; And

If there is loss of signal situation, then loss of signal alarm is sent to host computer system.

13. the method that provides according to claim 12 wherein comprises a plurality of registers that may threshold levels by visit and distributes described loss of signal thresholds level.

14. the method that provides according to claim 13, wherein said register and described processor are included in the control module on the printed circuit board (PCB) that is arranged in described optical transceiver module.

15. the method that provides according to claim 14 further comprises:

Convert the loss of signal thresholds level of described distribution to the analogue value from digital value.

16. the method that provides according to claim 15, wherein the step of more described received power further comprises:

To simulate received power value and described analog signal loss threshold level value compares.

17. the method that provides according to claim 16, wherein said input signal comprise the described data rate of described light signal.

18. the method that provides according to claim 17, the step of wherein visiting described input signal further comprises:

Visit the input signal that described host computer system provides.

19. wherein there is loss of signal situation in the method that provides according to claim 18 when the horizontally disposed value of the loss of signal thresholds of described distribution surpasses the value of described received power.

20. the method that provides according to claim 19, the described data rate of wherein said light signal in about 1 gigabit/sec in the scope of 10 gigabit/sec.

21. the method that provides according to claim 20, wherein the step of more described received power further comprises:

The comparator that is arranged in integrated post amplifier/laser driver parts compares the loss of signal thresholds level of described received power and described distribution to determine whether to exist loss of signal situation.