CN106130652A - Optical transmitter and transmission method - Google Patents

Abstract

An optical transmitter and a transmission method. The method is used for transmitting a data signal and a control signal to an optical receiver of a target device by an optical transmitter, and comprises the following steps: providing a data signal within a first frequency band; providing a control signal in a second frequency band; combining the data signal in the first frequency band with the control signal in the second frequency band to generate a combined signal; and converting the combined signal into an output optical signal for transmission to the optical receiver, wherein the control signal is used to control the target device.

Description

Optical transmitter and transmission method

technical field

The present invention relates to a communication system for high-speed serial data connection, in particular to a method for transmitting data and control signals through an optical cable and an optical transmitter using the communication system.

Background technique

An active optical cable (AOC) is a fiber optic cable with a plug at each end that includes an optical transceiver module for converting electrical signals to optical signals and converting optical signals to electrical signals .

Today's communication networks increasingly use active optical cables to increase transmission distances. However, communication networks usually use a large number of control signals and data signals for connection and communication between various networks. Control signals are generally transmitted through additional copper wires or optical fibers, so that the cost of establishing a communication network using active optical cables is greatly increased.

Contents of the invention

The present invention discloses an embodiment of a transmission method. An optical transmitter is used to transmit data signals and control signals to an optical receiver of a target device. The transmission method includes: providing a data signal in a first frequency band; providing a control signal in a second frequency band; combining the data signal in the first frequency band with the control signal in the second frequency band to generate a combined signal; and converting the combined signal into an output optical signal for to the optical receiver, where the control signal is used to control the target device.

The present invention discloses an embodiment of an optical transmitter for transmitting data signals and control signals to an optical receiver of a target device, and includes a control data converter, a combiner circuit and an electro-optic device. The control data converter is used for converting a control signal into a plurality of continuous wave (CW) signals having different predetermined frequencies according to different states of the control signal. The combiner circuit is coupled to the control data converter for combining a data signal in a first frequency band and the continuous wave signals to generate a combined signal. An electro-optic device is coupled to the combiner circuit for converting the combined signal into an output optical signal for transmission to the optical receiver.

Description of drawings

The present invention can be best understood from the following detailed description and examples referred to in the accompanying drawings, in which:

1 is a block diagram showing an optical communication system according to an embodiment of the present invention;

FIG. 2A is a circuit diagram showing an optical transmission device 2 according to an embodiment of the present invention;

FIG. 2B is a block diagram showing an optical transmission device 2 according to another embodiment of the present invention;

FIG. 3 is a block diagram showing an optical receiver 3 according to an embodiment of the present invention; and

FIG. 4 is a flowchart showing an optical transmission method according to an embodiment of the present invention.

【Symbol Description】

1～optical communication system;

2 ~ optical transmission device;

3 ~ optical receiver;

4～light transmission method;

D _t1 , D _t1' , D _t2 , D _t2' ~ data information;

S _ca , S _ca' , S _cb , S _cb' ~ control information;

S _opt , S _opt1 , S _opt2 ~ optical signal;

14a, 14b～optical cable;

D _t , D _t' , D _c10' , D _c11' ~ data signal;

D _tf ~filtered data signal;

D _c1 , D _c2 , S _c1 , S _c2 ~ control signal;

S _comb ~ binding signal;

freq _c10 , freq _c11 , freq _c20 , freq _c21 ~ frequency;

ND _C10 , ND _C11 , ND _C20 , ND _C21 ～predetermined frequency divider ratio;

10, 12～optical transmission device;

24, 100, 122 ~ optical transmitter;

102, 120～optical receiver;

22, 104, 124 ~ controller;

16～host device;

18 ~ target device;

20 ~ combiner circuit;

200, 202～switching device;

206, 207～control data converter;

204 ~ combiner;

210 ~ high pass filter;

208～Electro-optic device;

212, 214～frequency divider;

30～light-to-electricity device;

32, 34, 36 ~ filter;

S400, S402, S404, S406, S408, S410～steps.

detailed description

Follow-up is the content of the best embodiment of the present invention, and the purpose of this content is only to explain the basic principles of the present invention, rather than to limit the present invention, and the scope of the present invention should be defined by the scope of the attached patent application .

The embodiments described in the present invention are related to the optical communication system, and the optical communication system may be Universal Serial Bus (USB), Peripheral Interconnect Express (PCIe) system, High Resolution Multimedia Video Interface (HDMI) system, DisplayPort ( DP) system, accelerated image processing port (AGP) system, and other communication systems that use optical fiber as the transmission medium.

FIG. 1 is a block diagram of an optical communication system 1 according to an embodiment of the present invention. The optical communication system 1 includes a host device 16, a target device 18, and two optical transmission devices 10 and 12 coupled by optical cables 14a and 14b. The optical delivery device 10 is coupled to a host device 16 . Optical delivery device 12 is coupled to target device 18 . For example, the optical transmission devices 10 and 12 and the optical cables 14a and 14b constitute an active optical cable. The host device 16 communicates with the remote target device 18 using the communication information carried by the active optical cable. The host device 16 may include a USB host device or a PCIe host device, but is not limited thereto. The target device 18 may include a USB device or a Peripheral Express Interconnect standard device, but is not limited thereto. Fiber optic cables 14a and 14b may be constructed from separate cables or bonded cables.

For example, when optical delivery devices 10 and 12 and cables 14a and 14b form an active cable, the plugs at the ends of the active cable have a housing that plugs into circuit board sockets on host device 16 and target device 18 .

The host device 16 can electrically transmit data information and control information to the target device 18 through the two optical transmission devices 10 and 12 and the optical cables 14 a and 14 b. The target device 18 can electrically transmit data information and control information to the host device 16 through the two optical transmission devices 10 and 12 and the optical cables 14 a and 14 b. The control information from the host device 16 is used to regulate data transfer between the host device 16 and the target device 18 , or to manage the status of the target device 18 . In one embodiment, the control information and data information belong to the same communication protocol. Control data may include, but is not limited to, clock signals, reset signals, and power status signals. In a preferred embodiment, the control information from the host device 16 can be used as a remote wakeup signal to restore the operation of the target device 18 or a state switch signal to switch the state of the state machine in the target device 18 .

Data information and control information are obtained in the form of electrical signals, which are then encoded and converted into optical signals for optical transmission in the optical transmission devices 10 and 12 . For example, the optical transmission device 10 can transmit the optical signal S _opt1 including the data information D _t1 and the control information S _ca to the optical transmission device 12 through the optical cable 14a, and the optical transmission device 12 can transmit the optical signal S opt1 including the data information D _t2 and the control information S ca through the optical cable 14b. The optical signal S _{opt2 of the control information Scb is} sent to the optical transmission device 10 .

In operation, the optical transmission devices 10 and 12 can transmit data signals in the first frequency band shared by the optical signal S _opt1 or S _opt2 and transmit in the second frequency band shared by _the optical signal S _opt1 or S opt2 via the optical cables 14a and 14b Control signals to exchange data in the respective transmission direction. In other words, the optical transmission device 10 can transmit data signals in the first frequency band and control signals in the second frequency band to the optical transmission device 12 through the optical cable 14 a. Similarly, the optical transmission device 12 can transmit data signals in the first frequency band and control signals in the second frequency band to the optical transmission device 10 through the optical cable 14b. In addition, the communication protocol used for the communication between the host device 16 and the target device 18 can be the USB3.0 standard, but is not limited thereto. In the USB3.0 system, the data burst (burst) can be transmitted at a transmission rate of 5Gbps, or encoded in a frequency band between 500MHz and 2.5GHz in normal mode, and in idle mode by 10MHz to 50MHz Low Frequency Periodic Signals (LFPS) communicate with each other. Therefore, the control signal can be transmitted in frequency bands other than the frequency band 500 MHz to 2.5 GHz and the frequency band 10 MHz to 50 MHz. For example, control signals can be transmitted at a frequency lower than 10 MHz without causing interference to the transmission of data signals. Since data information and control information can be packaged into optical signals for transmission, it is no longer necessary to use separate copper wires or optical fibers to transmit control information between the optical transmission devices 10 and 12, but a common optical cable can be used for optical transmission, thus enabling Reduce the implementation cost of the transmission system.

The optical transmission device 10 includes an optical transmitter 100 , an optical receiver 102 and a controller 104 . The controller 104 coupled to the optical transmitter 100 and the optical receiver 102 is used to control the data flow and operation of the optical transmitter 100 and the optical receiver 102 . For the transmission path, the controller 104 receives the data information and the control information from the host device 16, and separates the data information D _t1 and the control information S _ca (that is, the data signal D _t1 and the control signal S _ca ) expressed in data form. Provided to the optical transmitter 100. The data D _t1 can optionally be transmitted in the normal mode within the frequency range of 500 MHz to 2.5 GHz in the first frequency band, or transmitted in the idle mode in the frequency range of 10 MHz to 50 MHz in the first frequency band. Next, the controller 104 processes the control information to form data S _ca , _which is a continuous wave signal having a second frequency that does not overlap with the first frequency. The optical transmitter 100 outputs a combined signal formed by combining the data D _t1 and S _ca , and then converts the combined signal into an optical signal S _opt1 , which is transmitted to the optical receiver 120 of the optical transmission device 12 through the optical cable 14 a. For the receiving path, the optical receiver 102 receives the optical signal S _opt2 from the optical transmission device 12, converts the optical signal S _opt2 back to an electrical signal, and separates and restores the data information from the electrical signal into data D _t2' and control information is the data S _cb' . The controller 104 can obtain the restored data D _{t2 ′} and _Scb′ and perform operations according to the restored data D _{t2 ′} and _Scb′ .

Similarly, the optical transmission device 12 includes an optical transmitter 122 , an optical receiver 120 and a controller 124 . The controller 124 coupled to the optical transmitter 122 and the optical receiver 120 is used to control the data flow and operation of the optical transmitter 122 and the optical receiver 120 . For the receiving path, the optical receiver 120 receives the optical signal S _opt1 from the optical cable 14a on the optical transmission device 10, converts the optical signal S _opt1 back to an electrical signal, and separates and restores the data information from the electrical signal to data D _{t1 '} and control information as data S _ca' . The controller 124 can obtain the restored data D _{t1 ′} and S _{ca ′} and perform operations according to the restored data D _{t1 ′} and S _{ca ′} . For the transmission path, the controller 124 receives the data information and the control information from the target device 18, and separates the data information D _t2 and the control information _Scb (that is, the data signal D _t2 and the control signal _Scb ) expressed in the form of data Provided to the optical transmitter 122. Similarly, the information D _t2 can be transmitted in the normal mode in the frequency range of 500 MHz to 2.5 GHz in the first frequency band, or in the idle mode in the frequency range of 10 MHz to 50 MHz in the first frequency band. Next, the controller 124 processes the control information to form data _Scb , _which is a continuous wave signal with a second frequency not overlapping with the first frequency. The optical transmitter 122 outputs a combined signal formed by combining the data D _t2 and _Scb , and then converts the combined signal into an optical signal S _opt2 , which is transmitted to the optical transmission device 10 through the optical cable 14b.

The optical communication system 1 allows the optical transmission device 10 and the optical transmission device 12 to transmit data information and control information through optical signals in a non-overlapping frequency band. That is, there is no need to generate a dedicated optical signal for transmitting control information. In the above-described manner, the implementation cost of establishing the optical communication system 1 is reduced.

FIG. 2A is a circuit diagram of an optical transmission device 2 according to an embodiment of the present invention. The optical transmission device 2 can be used as the optical transmission device 10 or 12 of FIG. 1 .

The optical transmission device 2 includes a controller 22 , a combiner circuit 20 , and an optical transmitter 24 . The combiner circuit 20 includes control data converters 206 and 207 and a combiner 204 . The optical transmitter 24 includes an electro-optical (E/O) device 208 . In one embodiment, the combiner circuit 20 can be an independent circuit, or can be integrated into the controller 22 . In a certain embodiment, the combiner 204 may be incorporated into the optical transmitter 24 and the two control data converters 206 and 207 may be incorporated into the controller 22 .

The data D _t is high-speed data, and its data frequency is between 500 MHz and 2.5 GHz (in other words, data is provided in the first frequency band). In one embodiment, the data is compatible with the USB3.0 standard. In FIG. 2A , two control data converters 206 and 207 respectively convert the electrical control signal into two different continuous wave signals with different frequencies. The frequencies of the two different continuous wave signals and the data frequency of the data D _t do not overlap. In one embodiment, the control data converter converts the control signal into a continuous wave signal at a predetermined frequency according to the state of the control signal. In an embodiment, the electrical control signal D _c1 has two valid states. For example, one of the states is "1", which represents a logic high potential, and the other state is "0", which represents a logic low potential. If the control signal D _c1 is logic high, the control data converter 206 converts the control signal D _c1 into a continuous wave signal at the first predetermined frequency. Similarly, if the control signal D _c1 is logic low, the control data converter 206 converts the control signal D _c1 into another continuous wave signal at the second predetermined frequency. In an alternative embodiment, the first predetermined frequency may represent an active state of the electrical control signal, while not being at the first predetermined frequency may represent another active state of the electrical control signal. Besides, both the first predetermined frequency and the second predetermined frequency are lower than the frequency band of the data signal.

Please refer to FIG. 2A , two switching devices 200 and 202 can serve as the above-mentioned control data converter. The control signals D _c1 and D _c2 serve as switching control signals SW1 and SW2 for controlling the switching devices 200 and 202 , respectively. The frequencies freq _c10 , freq _c11 , freq _c20 , and freq _c21 are different from the data frequency of the data D _t and may be in a low frequency range, such as less than 20 MHz, but are not limited thereto. The four frequencies freq _c10 , freq _c11 , freq _c20 , and freq _c21 can be generated from a single signal source, or can be generated from different signal sources. Furthermore, the frequencies freq _c10 , freq _c11 , freq _c20 , and freq _c21 are different from each other, freq _c10 and freq _c11 represent the two states of the control signal D _c1 respectively, and freq _c20 and freq _c21 represent the two states of the control signal D _c2 respectively . For example, the frequencies freq _c10 and freq _c11 may be 4 MHz and 5 MHz, respectively. When the control signal D _c1 is in the first logic state, the switching device 200 selects the frequency freq _c10 (4 MHz frequency) as an electrical control signal S _c1 and outputs it to the combiner 204 . When the control signal D _c1 is in the second logic state, the switching device 200 selects the frequency freqc11 (5 MHz frequency) as an electrical control signal S _c1 and outputs it to the combiner 204 . Switching device 202 operates in the same manner. When the control signal D _c2 is in the first logic state, the switching device 202 selects the frequency freq _c20 as the electrical control signal S _c2 and outputs it to the combiner 204 . When the control signal D _c2 is in the second logic state, the switching device 202 selects the frequency freq _c21 as the electrical control signal S _c2 and outputs it to the combiner 204 . In addition, the data D _{t is} filtered by the high-pass filter 210 before reaching the combiner 204 to generate a filtered data signal D _tf to ensure that the data signal D _t is more accurate. The switching devices 200 and 202 select the frequencies freq _c10 , freq _c11 , freq _c20 and freq _c21 through the control signals D _c1 and D _c2 , and output the selected frequencies (electrical control signals S _c1 and S _c2 ) to the combiner 204 respectively , the combiner 204 combines the selected frequency and the filtered data signal Dtf to generate a combined signal S _comb . Since the frequencies freq _c10 , freq _c11 , freq _c20 , and freq _c21 and the frequency of the data D _t do not overlap with each other, they will not interfere with each other in the combined signal S _comb .

The electro-optical device 208 includes a laser diode (not shown) or other suitable laser devices that can replace a laser diode. A laser diode generates an optical carrier signal with a predetermined carrier frequency and a wide frequency bandwidth. The electro-optic device 208 receives the combination signal S _comb from the combiner 204 , modulates the combination signal S _comb with an optical carrier signal, and outputs an optical signal S _opt for communication through an optical fiber (not shown). In one embodiment, the electro-optic device 208 only receives the combined signal S _comb and converts the combined signal S _comb into an optical signal S _opt for any subsequent transmission mode.

Please refer to FIG. 2B , which is a circuit diagram of another embodiment of the optical transmission device 2 according to the present invention. The difference between FIG. 2A and FIG. 2B is that the control data converter is realized by two programmable frequency dividers 214 and 212 . The two programmable frequency dividers 214 and 212 both receive the same frequency from the frequency source freq. The control signals D _c1 and D _c2 are regarded as frequency divider control signals, and the corresponding ratio of the frequency divider is selected according to the states of the control signals D _c1 and D _c2 respectively. When the control signal D _c1 is in the first logic state, the frequency divider 214 selects the first predetermined frequency divider ratio ND _C10 , and outputs a frequency freq _c10 (4MHz) as an electrical control signal S _c1 to be sent to the combiner 204 . When the control signal D _c1 is in the second logic state, the frequency divider 214 selects the second predetermined frequency divider ratio ND _C11 , and outputs a frequency freq _c11 (5 MHz) as an electrical control signal S _c1 to be sent to the combiner 204 . Frequency divider 212 operates in the same manner. When the control signal D _c2 is in the first logic state, the frequency divider 212 selects the third predetermined frequency divider ratio ND _C20 , outputs a frequency freq _c20 as an electrical control signal Sc2, and transmits it to the combiner 204 . When the control signal D _c2 is in the second logic state, the frequency divider 212 selects the fourth predetermined frequency divider ratio NDC21 , outputs a frequency freq _c21 as an electrical control signal S _c2 , and transmits it to the combiner 204 . The frequencies freq _c10 , freq _c11 , freq _c20 , and freq _c21 are different from the data frequency of the data D _t and may be in a low frequency range, such as below 20 MHz, but not limited thereto. In addition, the data D _{t is} filtered by the high-pass filter 210 before reaching the combiner 204 to generate a filtered data signal D _tf to ensure that the data signal Dt is more accurate. The combiner 204 combines the output frequencies of the control data converters 206 and 207 with the filtered data signal D _tf to generate a combined signal S _comb . Since the frequencies freq _c10 , freq _c11 , freq _c20 , and freq _c21 and the frequency of the data D _t do not overlap with each other, they will not interfere with each other in the combined signal S _comb . Although FIG. 2A and FIG. 2B only show two control signals D _c1 and D _c2 , those skilled in the art can realize that more than two control data can be converted and multiplexed into optical signals according to the same principles disclosed in the embodiments. S _opt .

The optical transmission devices 10 and 12 allow the host device 16 and the target device 18 to transmit data information and control information via optical signals at non-overlapping frequencies, thereby reducing the implementation cost of optical cables.

FIG. 3 is a block diagram of an optical receiver 3 according to an embodiment of the present invention. The optical receiver 3 can serve as the optical receivers 102 and 120 of FIG. 1 . The optical receiver 3 receives the optical signal S _opt for transmission through the optical cable, and recovers electrical data and control signals from the optical signal S _opt .

The optical receiver 3 includes light-to-electricity devices and filters 32 , 34 and 36 . The photoelectric conversion device 30 includes a photodetector (not shown) and a transimpedance amplifier (Transimpedance Amplifier, TIA) (not shown). The photodetector detects light waves of the optical signal S _opt , and the transimpedance amplifier converts the detected optical signal S _opt into a corresponding electrical signal.

The filters 32 , 34 and 36 are respectively used to filter the electrical data signal D _t′ , the frequencies freq _c10 and freq _c11 . Filters 32, 34, and 36 may be bandpass filters, allowing electrical data and control signals to be separated from converted electrical signals. The operating frequency bands of the filters 32, 34 and 36 can be predetermined to comply with the spectrum design set out by the optical transmission device. Alternatively, the optical receiver 3 may also include a frequency detection circuit (not shown) for actively detecting all available frequency components in the optical signal S _opt and configuring the operating frequency bands of the filters 32 , 34 and 36 correspondingly. For example, filter 32 can be configured to separate out signals in the 500MHz–2.5GHz frequency band, filter 34 can be configured to separate out frequency band signals centered around 4MHz, and filter 36 can be configured to separate out signals in the frequency band centered around 5MHz frequency band signal. In another embodiment, a bandpass filter (not shown in FIG. 3 ) is added before the filters 34 and 36 to filter out lower frequency ranges, such as below 20 MHz. Besides, since the filter 32 is configured to separate the electrical data signal D _t′ occupying the highest frequency spectrum, the filter 32 can also be a high-pass filter. Figure 3 does not show the corresponding filters for filtering out freq _c20 and freq _c21 .

The optical receiver 3 allows the host device and the target device to identify data information and control information from an optical signal, so as to reduce the implementation cost of the optical cable.

FIG. 4 is a flow chart of an optical transmission method 4 according to an embodiment of the present invention. The method cooperates with the optical communication system 1 of FIG. 1 and the optical transmission device 2 of FIGS. 2A and 2B . This optical transmission method is activated when the host device 16 or the target device 18 wants to transmit data signals and control signals through the active optical cable.

After the optical transmission method is activated, the host device 16 is connected to the target device 18 through the active optical cable, and prepares to transmit data and control information through the active optical cable 14a (S400).

Next, an electrical data signal D _t within a first frequency band is provided ( S402 ). In an embodiment, the optical transmitter 100 is configured to transmit an electrical data signal D _t in a first frequency band. The first frequency band may range between 500MHz and 2.5GHz. In addition, the high-pass filter 210 pre-filters the data D _t to generate a filtered data signal D _tf so as to ensure that the data signal D _t is more accurate.

At the same time, an electrical control signal Sc within the second frequency band is provided ( _S404 ). The second frequency band does not overlap with the first frequency band, and the range of the second frequency band may eg be between 0 Hz and 10 MHz. The electrical control signal D _c and the data signal D _t belong to the same communication protocol.

In some embodiments, the optical transmitter 100 is configured to transmit the electrical control signal _Dc , and convert the electrical control signal _Dc to an electrical frequency within the second frequency band according to the state of the electrical control signal _Dc . Sexual control signal S _c . The control data converter is implemented in the optical transmitter 100 and is configured to convert the electrical control signal D _c into the electrical control signal S _{c in the second frequency band according to the state of the electrical control signal D c .} In one embodiment, the control data converter converts the control signal into a continuous wave signal in the second frequency band according to the state of the control signal. In one embodiment, the electrical control signal D _c has two active states. For example, "1" indicates a logic high potential state, and "0" indicates a logic low potential state. If the control data D _c indicates a high potential state, the control data converter converts the control data D _c into a continuous wave with a first predetermined frequency. Similarly, if the control data D _c indicates a low potential state, the control data converter converts the control data D _c into a continuous wave with a second predetermined frequency. In other embodiments, the first predetermined frequency may indicate that the electrical control signal is in an active state, and not being at the first predetermined frequency may indicate that the electrical control signal is in another active state. Besides, both the first predetermined frequency and the second predetermined frequency are lower than the frequency band of the data signal.

In other embodiments, the optical transmitter 100 converts the electrical control signal D _c into an electrical control data S _{c that only represents the state of a predetermined frequency band of the electrical control signal D c .} That is to say, when the electrical control signal S _c is not received, the optical receiver 120 automatically recognizes that the electrical control signal D _c is in a state other than the predetermined state, and when receiving the electrical control signal S _c , The optical receiver 120 automatically recognizes the electrical control signal D _c as a predetermined state.

The combiner circuit 20 then combines the data signal D _t or the filtered data signal D _tf in the first frequency band and the electrical control signal _{Sc in the second frequency band to generate a combined signal S comb (} S406 ). Since the data signal and the electrical control signal use non-overlapping frequency bands, the two signals will not interfere with each other in the combined signal S _comb .

Finally, the electro-optic device 208 is used to convert the combined signal S _comb into an output optical signal S _opt ( S408 ), and transmit the output optical signal S _opt to the target device 18 through an optical cable. Since data and control signals can be carried on the same optical signal S _opt without mutual interference, only one optical cable is required for transmission. Thus, the implementation cost of establishing an optical communication network is reduced.

Although the embodiments in the preceding paragraphs use the host device 16 to show each step of the optical transmission method. It should be appreciated that target device 18 can also employ optical transmission methods for transmission from target device 18 to host device 16 .

The optical transmission method allows the host device and the target device to transmit data information and control information through optical signals on non-overlapping frequency bands, thereby reducing the implementation cost of establishing the optical communication system 1 .

The word "judgment" used in the present invention includes calculation, calculation, operation, acquisition, investigation, query (eg query table, database or other data structures), determination, etc. "Judgment" also includes the meaning of solving, choosing, choosing, establishing, etc.

By general-purpose processors, digital signal processors (Digital Signal Processor, DSP), application-specific integrated circuits (Application Specific Integrated Circuit, ASIC), programmable planning logic elements (Field Programmable Gate Array, FPGA) or other programmable logic elements , discrete logic circuits or transistor logic gates, discrete hardware components, electrical components, optical components, mechanical components, or any combination used to perform the execution functions described in the present invention, to realize or represent various aspects disclosed in the description of the present invention Logic blocks, modules, and circuits. A general-purpose processor can be a microprocessor, but in the alternative, the processor can be any commercially available processor, controller, microprocessor, or state machine.

The functions and operations of various logic blocks, modules, and circuits disclosed in the description of the present invention are realized by circuit hardware or embedded software codes executed and accessed by a processor.

While the invention has been described by way of representation by way of illustration and embodiment, the invention is not limited to the disclosed embodiments. On the contrary, the invention is intended to cover various modifications and similar arrangements (obvious to those skilled in the art). Therefore, the appended claims should be interpreted in the broadest way to cover all modifications and similar arrangements.

Claims (15)

1. A transmission method for transmitting data signals and control signals to an optical receiver of a target device through an optical transmitter, the transmission method comprising: providing a data signal in the first frequency band; providing a control signal within the second frequency band; combining the data signal in the first frequency band with the control signal in the second frequency band to generate a combined signal; and The combined signal is converted into an output optical signal for transmission to the optical receiver, wherein the control signal is used to control the target device. 2. The transmission method as claimed in claim 1, wherein the control signal has two valid states, and the first predetermined frequency in the second frequency band represents an active state of the control signal, and in the second frequency band The second predetermined frequency of represents another valid state of the control signal. 3. The transmission method as claimed in claim 1, wherein the control signal has two valid states, and a predetermined frequency in the second frequency band represents an active state of the control signal, and is not in the second frequency band The predetermined frequency of represents another valid state of the control signal. 4. The transmission method as claimed in claim 1, wherein the frequency range covered by the second frequency band is lower than the frequency range of the first frequency band. 5. The transmission method as claimed in claim 1, wherein the step of providing the control signal in the second frequency band comprises: According to different states of the control signal, the control signal is converted into a plurality of continuous wave signals respectively having different predetermined frequencies. 6. The transmission method as claimed in claim 1, wherein the step of providing the control signal in the second frequency band comprises: A corresponding frequency is selected within the second frequency band according to a state of the control signal. 7. The transmission method as claimed in claim 1, wherein the second frequency band does not overlap with the first frequency band. 8. An optical transmitter for transmitting data signals and control signals to an optical receiver of a target device, the optical transmitter comprising: controlling the data converter, which is used to respectively convert the control signal into a plurality of continuous wave signals with different predetermined frequencies according to different states of the control signal; a combiner circuit, coupled to the control data converter, for combining the data signal in the first frequency band with the continuous wave signal to generate a combined signal; and The electro-optic device is coupled to the combiner circuit and used for converting the combined signal into an output optical signal for transmission to the optical receiver. 9. The optical transmitter as claimed in claim 8, wherein the control signal has two valid states, and when the control signal is in the first state, the control data converter converts the control signal into a continuous signal having a first predetermined frequency wave signal, and when the control signal is in a second state, the control data converter converts the control signal into a continuous wave signal having a second predetermined frequency. 10. The optical transmitter as claimed in claim 8, wherein the control signal has two valid states, and when the control signal is in the first state, the control data converter converts the control signal into a continuous signal having a first predetermined frequency wave signal, and when the control signal is in a second state, the control data converter converts the control signal into a continuous wave signal having a second predetermined frequency; and a predetermined frequency within the second frequency band represents that the control signal is in a An active state other than the predetermined frequency within the second frequency band represents that the control signal is in another active state. 11. The optical transmitter as claimed in claim 8, wherein the frequency range covered by the second frequency band is lower than the frequency range of the first frequency band. 12. The optical transmitter as claimed in claim 8, wherein the control data converter is configured to respectively convert the control signal into the continuous wave signal with different predetermined frequencies according to different states of the control signal. 13. The optical transmitter as claimed in claim 8, wherein the control data converter is used as a switch for selecting a frequency in the second frequency band according to the state of the control signal. 14. The optical transmitter as claimed in claim 8, wherein the control data converter acts as a programmable frequency divider coupled to a frequency source, and the control data converter selects a frequency division ratio according to the state of the control signal to A divided frequency within the second frequency band is output. 15. The optical transmitter as claimed in claim 8, wherein the control signal is used to control the target device to transmit data and control data belonging to the same protocol.