CN116009289A - Bias voltage control method for large-scale MZ modulator array - Google Patents

Abstract

The application provides a bias control method of a large-scale MZ modulator array, which comprises the following steps: initializing; calibrating bias control points of all channels; the optical switch is used for repeatedly and circularly rapidly monitoring the amplitude change of the optical signals of all channels, the bias control output response of the channels is dynamically adjusted, so that the amplitude parameters of the optical signals are consistent with the amplitude parameters in the initialization process, a new lookup table of the optical signal amplitude parameters of different channels and the optimal bias point positions is established, the lookup table is updated in real time according to the monitoring condition, and the bias control output response is adjusted. The method provided by the application can greatly reduce the number of the bias control modules of the MZ modulator in the multichannel optical multi-beam network system, and greatly reduce the system volume.

Description

A Bias Control Method for Large Scale MZ Modulator Array

technical field

The present application relates to the field of optical multi-beam forming network technology, and in particular to a bias voltage control method of a large-scale MZ modulator array.

Background technique

The optical multi-beam forming network is an important part of the optical phased array radar system and the core unit of the beam forming in the optical phased array radar. The optical multi-beam forming network consists of multiple channels, and each channel includes a light source, an electro-optic modulator (Mach-Zehnder modulator is MZ modulator, which belongs to the intensity modulator and is also a kind of electro-optic modulator), detectors, etc. . In the optical multi-beam forming network, the MZ modulator is easily affected by the external temperature, and its modulation response curve is prone to drift. In order to ensure the stability of the radio frequency signal, it is necessary to complete the MZ modulator in a very short time (second level). The adjustment of the working point of the bias voltage, and in the actual application process, the scale of the optical multi-beam forming network is often large, and the number of corresponding MZ modulators is also large, and the response characteristics of different MZ modulators are also different. The position of the pressure working point is also different. Therefore, in a large-scale optical multi-beam forming network, it is necessary to adjust and control the working point of the large-scale MZ modulator array in real time, so as to ensure the stability of the radio frequency signal modulated on the MZ modulator.

Aiming at the bias control of large-scale MZ modulator arrays, the method of individually controlling each MZ modulator is currently adopted, that is, a separate bias control board is designed for each MZ modulator. Although this method can ensure the normal operation of each MZ modulator, as the number of channels increases, the number of MZ modulators increases. This method is not suitable for the application of large-scale optical multi-beam forming networks, and a new MZ modulator needs to be designed. The bias control architecture of the array solves the problem of too many MZ modulator bias control boards in the application of large-scale MZ modulator arrays, reduces the number of boards, and is conducive to the integration of large-scale optical multi-beam forming network systems.

Contents of the invention

The present application provides a method for controlling the bias voltage of a large-scale MZ modulator array, which can be used to solve the technical problem of inefficiency in the bias control of a large-scale mz modulator array in the prior art.

The present application provides a bias voltage control method of a large-scale MZ modulator array, the method is applied to a bias voltage control system of a large-scale MZ modulator array, and the system includes:

Multiple channels, and a high-speed optical switch module, a signal parameter detection module, a centralized control module, a signal parameter detection module, and a bias voltage control module connected to each channel;

Wherein, each channel sequentially includes an input terminal, a laser, an MZ regulator and a splitter;

The splitter is respectively connected to the optical network and the high-speed optical switch module;

The first step, initialization processing:

According to the theoretical value of the half-wave voltage of the MZ modulator, adjust the bias voltage control points of the MZ modulator of all channels to the theoretical value;

The second step is to calibrate the bias control points of all channels;

The third step is to quickly monitor the amplitude changes of the optical signals of all channels through the optical switch, and dynamically adjust the bias voltage control output response of the channel so that the amplitude parameters of the optical signals are consistent with the amplitude parameters at the time of initialization, and a new one is established. A look-up table of the optical signal amplitude parameters of different channels and the position of the best bias point is provided, and the look-up table is updated in real time according to the monitoring situation to adjust the output response of the bias voltage control.

Optionally, calibrate the bias control points of all channels, including:

Quickly switch to all channels through the optical switch, and quickly adjust the bias value of the MZ modulator according to the theoretical value of the half-wave voltage, so as to obtain the best bias point position of the MZ modulator of the channel;

And dynamically adjust the bias voltage control output response of the MZ modulator, and record the amplitude parameters of the optical signal at this time;

After the calibration of the bias voltage control points of all channels is completed, a look-up table of optical signal amplitude parameters of different channels and optimal bias point positions is established.

Optionally, the optical switch performs us-level switching for multiple channels.

Optionally, the splitter divides the optical signal corresponding to the channel into 5% of the first optical signal and 95% of the second optical signal, the first optical signal enters the centralized control module, and the second optical signal enters the optical network.

Optionally, the signal parameter detection module includes a photodetector, a filter, an amplifier and an ADC module.

The method provided by this application can greatly reduce the number of MZ modulator bias control modules in the multi-channel optical multi-beam network system, and greatly reduce the system volume. After adopting the method provided by this application, the output of different MZ modulators can be concentrated corresponding parameters.

Description of drawings

Fig. 1 is a functional block diagram of a bias control method for a large-scale MZ modulator array in an optical multi-beam network provided by an embodiment of the present application;

FIG. 2 is a block diagram of the implementation of the bias control architecture of the 16-channel MZ modulator array provided by the embodiment of the present application;

FIG. 3 is a block diagram of a method for bias voltage control of an FPGA-based multi-channel MZ modulator provided by an embodiment of the present application.

Detailed ways

In order to make the purpose, technical solution and advantages of the present application clearer, the implementation manners of the present application will be further described in detail below in conjunction with the accompanying drawings.

As shown in Figure 1, taking the M-channel optical multi-beam network system as an example, the MZ modulators of different channels give initial responses through the bias control module, and the centralized control module controls the switching of the optical switch (the switching time of the optical switch is us level), if the number of channels M is large, the optical switch can be cascaded through several optical switches to complete the high-speed switching of the optical switch of M channels, and the signal detection module can monitor the switching of a certain channel by using the coupled 5% optical signal According to the change of optical signal amplitude parameters, the bias output response of the MZ modulator corresponding to the channel is dynamically adjusted in real time. After all channels have completed parameter monitoring and dynamically adjusted bias control responses, repeat monitoring of all channels according to a certain timing and strategy According to the parameter change, according to the transmission response characteristics of the MZ modulator, the deviation of the bias voltage control point of the MZ modulator is very small within a certain period of time (second level), and the method provided by this application can meet the practical application.

The present application provides a bias control method for a large-scale MZ modulator array. The method provided by the present application is applied to a bias control system for a large-scale MZ modulator array. The system includes:

Multiple channels, and a high-speed optical switch module, a signal parameter detection module, a centralized control module, a signal parameter detection module, and a bias voltage control module connected to each channel;

Wherein, each channel sequentially includes an input terminal, a laser, an MZ regulator and a splitter;

The splitter is respectively connected to the optical network and the high-speed optical switch module. The optical switch performs us-level switching on multiple channels.

The splitter divides the optical signal corresponding to the channel into 5% of the first optical signal and 95% of the second optical signal, the first optical signal enters the centralized control module, and the second optical signal enters the optical network.

The signal parameter detection module includes a photodetector, a filter, an amplifier and an ADC module.

The first step, initialization processing:

According to the theoretical value of the half-wave voltage of the MZ modulator, the bias voltage control points of the MZ modulator of all channels are adjusted to the theoretical value.

The second step is to calibrate the bias control points of all channels.

Specifically, the optical switch is used to quickly switch to all channels, and according to the theoretical value of the half-wave voltage, the bias voltage value of the MZ modulator is quickly adjusted, so as to obtain the best bias point position of the MZ modulator of the channel;

And dynamically adjust the bias voltage control output response of the MZ modulator, and record the amplitude parameters of the optical signal at this time;

After the calibration of the bias voltage control points of all channels is completed, a look-up table of optical signal amplitude parameters of different channels and optimal bias point positions is established.

The third step is to quickly monitor the amplitude changes of the optical signals of all channels through the optical switch, and dynamically adjust the bias voltage control output response of the channel so that the amplitude parameters of the optical signals are consistent with the amplitude parameters at the time of initialization, and a new one is established. A look-up table of the optical signal amplitude parameters of different channels and the position of the best bias point is provided, and the look-up table is updated in real time according to the monitoring situation to adjust the output response of the bias voltage control.

Quickly switch to all channels through the optical switch, and quickly adjust the bias value of the MZ modulator according to the theoretical value of the half-wave voltage, so as to obtain the best bias point position of the MZ modulator of the channel;

And dynamically adjust the bias voltage control output response of the MZ modulator, and record the amplitude parameters of the optical signal at this time;

After the calibration of the bias voltage control points of all channels is completed, a look-up table of optical signal amplitude parameters of different channels and optimal bias point positions is established.

As shown in FIG. 2 , it is a block diagram of the implementation of the bias control architecture of the large-scale MZ modulator array in the example of the present invention. The MZ modulator array bias control system mainly includes an optical switch, a centralized control module, a signal parameter detection module, and a bias control module. In this example, the optical switch uses a 16-channel magneto-optical switch. The main function of the centralized control module is to realize the switching of high-speed optical switches, process the data obtained by the signal detection module, quickly give the output response of the channel, and give the bias The output response value of the pressure control module. The signal parameter detection module mainly consists of a photodetector, a filter, an amplifier, and an ADC module. It mainly realizes the photoelectric conversion of 5% optical signal, and quantifies the converted electrical signal through ADC. The bias voltage control module mainly includes a latch, a multi-channel DAC and an operational amplifier. At the output port of each MZ modulator, split 5% of the optical signal through a splitter and connect it to the optical switch module. The centralized control realizes the us-level switching of the multi-channel optical switch through the optical switch switching circuit. After the optical switch The output optical signal converts the optical signal into an electrical signal through the photodetector, the signal detection module performs quantization processing through the ADC, and the centralized control module obtains the optical power value of the channel by reading the quantization parameters output by the ADC. Segment search and comparison search to quickly obtain the best bias point of the MZ modulator corresponding to the channel, so as to establish a new lookup table of optical power and bias output of different channels. After completing the calibration of the bias control output response of all channels, the optical signal of the MZ modulator of all channels is repeatedly detected, the output response is dynamically adjusted in real time, and the look-up table of the optical power and bias output of new different channels is established repeatedly .

The method provided by this application can greatly reduce the number of MZ modulator bias control modules in the multi-channel optical multi-beam network system, and greatly reduce the system volume. In addition, after adopting this method, the corresponding parameters of different MZ modulators can be centrally output .

The embodiments of the present application described above are not intended to limit the scope of protection of the present application.

Claims (5)

1. a kind of bias control method of large-scale MZ modulator array, it is characterized in that, described method is applied to the bias control system of large-scale MZ modulator array, and described system comprises: Multiple channels, and a high-speed optical switch module, a signal parameter detection module, a centralized control module, a signal parameter detection module, and a bias voltage control module connected to each channel; Wherein, each channel sequentially includes an input terminal, a laser, an MZ regulator and a splitter; The splitter is respectively connected to the optical network and the high-speed optical switch module; The first step, initialization processing: According to the theoretical value of the half-wave voltage of the MZ modulator, adjust the bias voltage control points of the MZ modulator of all channels to the theoretical value; The second step is to calibrate the bias control points of all channels; The third step is to quickly monitor the amplitude changes of the optical signals of all channels through the optical switch, and dynamically adjust the bias voltage control output response of the channel so that the amplitude parameters of the optical signals are consistent with the amplitude parameters at the time of initialization, and a new one is established. A look-up table of the optical signal amplitude parameters of different channels and the position of the best bias point is provided, and the look-up table is updated in real time according to the monitoring situation to adjust the output response of the bias voltage control. 2. The method according to claim 1, wherein calibrating the bias control points of all channels comprises: Quickly switch to all channels through the optical switch, and quickly adjust the bias value of the MZ modulator according to the theoretical value of the half-wave voltage, so as to obtain the best bias point position of the MZ modulator of the channel; And dynamically adjust the bias voltage control output response of the MZ modulator, and record the amplitude parameters of the optical signal at this time; After the calibration of the bias voltage control points of all channels is completed, a look-up table of optical signal amplitude parameters of different channels and optimal bias point positions is established. 3. The method according to claim 1, wherein the optical switch performs us-level switching on multiple channels. 4. The method according to claim 1, wherein the splitter divides the optical signal corresponding to the channel into 5% of the first optical signal and 95% of the second optical signal, and the first optical signal enters the centralized control module , the second optical signal enters the optical network. 5. The method according to claim 1, wherein the signal parameter detection module comprises a photodetector, a filter, an amplifier and an ADC module.

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