CN110635851B - Modulator driving method and system suitable for quantum state random optical signals - Google Patents
Modulator driving method and system suitable for quantum state random optical signals Download PDFInfo
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Abstract
The invention provides a modulator driving method and a system suitable for quantum state random optical signals, wherein the system comprises the following steps: an input terminal group including at least two input terminals; each input end is used for inputting aligned random input signals; an adjustable gain amplifier group comprising at least two adjustable gain amplifiers; the broadband resistor network terminal is used for combining the voltage signals output by the adjustable gain amplifiers and outputting combined signals; a broadband amplifier for amplifying the combined signal to an amplitude required for modulation to form a driving signal; the signal ground port of the modulator is connected with a power supply, the power supply signal is processed by the modulator and then is loaded on the broadband amplifier through the radio frequency port, and the modulator receives a driving signal output by the broadband amplifier from the radio frequency port and modulates the quantum state random optical signal input into the modulator according to the driving signal. The invention can meet the broadband drive of 0 Hz-10 GHz level, and effectively solve the problem of substrate shake.
Description
Technical Field
The invention relates to the technical field of quantum communication, in particular to the technical field of quantum signal driving, and specifically relates to a modulator driving method and system suitable for quantum state random optical signals.
Background
The modulator driving system suitable for the quantum state random optical signal in the prior art scheme, as shown in fig. 1, comprises a quantum state random input signal, an alternating current coupling capacitor, an adjustable gain amplifier, a broadband resistor network, a broadband amplifier, an inductor or bais_t and a modulator.
The AC coupling capacitor functions to pass the AC component of the input signal but not the DC component; the adjustable gain amplifier is used for amplifying the received signal, and the gain is adjustable so as to adjust the voltage value finally output to the modulator; the broadband resistance network function is to combine and output two paths of signals; the broadband amplifier is used for amplifying an input signal; the inductor or bais_t functions to enable the power supply to supply power to the broadband amplifier and to enable the signal not to be split in the direction of the power supply; the function of the modulator is to receive the RF signal and then to modulate the optical signal passing through, which may be a phase modulator or an intensity modulator.
In the field of quantum communication, four random level pulse signals of 0,1/2,1,3/2 are commonly used for modulating a modulator, in the existing scheme, an adjustable gain amplifier of one channel can be configured to enable the output signal amplitude of the adjustable gain amplifier to be half of the output amplitude of the other channel, and then superposition output is carried out in a rear-end broadband resistor network, so that after high-speed random optical signals are loaded at two input ends, four level driving signals of 0,1/2,1,3/2 can be superposed for driving the modulator.
The prior proposal adopts a broadband matching design, can meet the broadband amplification of the level of 100 KHz-10 GHz, and can control the degradation of the signal quality within a certain range relative to a non-broadband matching design because the low frequency reaches 100KHz, thus being marginally applicable to a modulator system with lower signal quality requirement. However, in a system with high signal quality requirements, the error rate of the system is increased and the performance of the system is greatly reduced due to signal quality problems such as substrate jitter and amplitude jitter. And because the frequency spectrum component of the quantum state random optical signal is very wide, the low end is close to 0Hz (namely direct current), the high end is several times of the system frequency, and if the signal is amplified without distortion, the driving scheme needs to cover the low end and the high end. In practical application, the high-side is easy to realize, the low-side is difficult to realize, and the low-side signal can be restrained due to the existence of an alternating-current coupling capacitor and an inductor or bais_t. The low frequency of the broadband of the driving circuit is not low enough, which can lead to signal distortion and poor signal quality after random optical signal amplification.
Disclosure of Invention
In view of the above-mentioned drawbacks of the prior art, an object of the present invention is to provide a method and a system for driving a modulator suitable for a quantum state random optical signal, which are used for solving the problems of substrate jitter and poor signal quality caused by insufficient broadband low frequency existing in the existing modulator driving system suitable for a quantum state random optical signal.
To achieve the above and other related objects, the present invention provides a modulator driving system adapted for quantum state random optical signals, comprising: an input terminal group including at least two input terminals; each input end is used for inputting aligned random input signals respectively; an adjustable gain amplifier group comprising at least two adjustable gain amplifiers; each adjustable gain amplifier is connected with the input end in a one-to-one correspondence manner, and is used for amplifying and adjusting the gain of the corresponding random input signal and outputting the adjusted voltage signal; the broadband resistor network terminal is in communication connection with the adjustable gain amplifier group and is used for combining the voltage signals output by the adjustable gain amplifiers and outputting combined signals; the broadband amplifier is in communication connection with the broadband resistance network terminal and is used for amplifying the combined signal to the amplitude required by modulation to form a driving signal; a modulator; the signal ground port of the modulator is connected with a power supply, and a power supply signal is loaded onto the broadband amplifier through a radio frequency port after being processed by the modulator; the modulator receives the driving signal from the radio frequency port and modulates the quantum state random optical signal input into the modulator according to the driving signal.
In an embodiment of the present invention, the modulation amount of the quantum state random optical signal by the modulator is a modulation amount corresponding to a difference between the voltage of the radio frequency port and the voltage of the signal ground port.
In an embodiment of the present invention, when in an unmodulated working state, the random encoding signal output by the modulator is a high level signal, and a difference between a voltage of the radio frequency port and a voltage of the signal ground port is 0; when in a modulation working state, the random coding signal output by the modulator is a low-level signal, and the voltage of the radio frequency port and the voltage of the signal ground port have a difference value.
In an embodiment of the invention, the adjustable gain amplifier is an adjustable gain amplifier capable of adapting to a dc input/output signal; the broadband amplifier is a broadband amplifier which can adapt to direct current input and output signals.
In one embodiment of the present invention, the input terminal set includes two input terminals for inputting two aligned random input signals; the adjustable gain amplifier group comprises two adjustable gain amplifiers; wherein the output signal amplitude of one of the adjustable gain amplifiers is half of the output signal amplitude of the other of the adjustable gain amplifiers.
In one embodiment of the present invention, the input terminal set includes three input terminals for inputting three-way aligned random input signals; the adjustable gain amplifier group comprises three adjustable gain amplifiers; the output signal amplitudes of the three adjustable gain amplifiers are 1/2,1 and 3/2 respectively.
The embodiment of the invention also provides a modulator driving method suitable for the quantum state random optical signal, which comprises the following steps: inputting at least two paths of aligned random input signals; amplifying the input signal by at least two adjustable gain amplifiers, adjusting the gain and outputting the adjusted voltage signal; the output voltage signals are combined through a broadband resistance network terminal, and a combined signal is output; amplifying the combined signal to the amplitude required by modulation through a broadband amplifier to form a driving signal; connecting a signal ground port of a modulator with a power supply, processing a power supply signal by the modulator, loading the power supply signal onto the broadband amplifier through a radio frequency port, and receiving the driving signal output by the broadband amplifier from the radio frequency port by the modulator and modulating a quantum state random optical signal input into the modulator according to the driving signal.
In an embodiment of the present invention, the modulation amount of the quantum state random optical signal by the modulator is a modulation amount corresponding to a difference between the voltage of the radio frequency port and the voltage of the signal ground port.
In an embodiment of the present invention, when in an unmodulated working state, the random encoding signal of the modulator outputs a high level signal, and a difference between a voltage of the radio frequency port and a voltage of the signal ground port is 0; when in a modulation working state, the random coding signal output by the modulator is a low-level signal, and the voltage of the radio frequency port and the voltage of the signal ground port have a difference value.
In an embodiment of the invention, the adjustable gain amplifier is an adjustable gain amplifier adapted to the dc input/output signal and/or the wideband amplifier is a wideband amplifier adapted to the dc input/output signal.
In one embodiment of the present invention, two paths of aligned random input signals are input, and the two adjustable gain amplifiers are correspondingly two; wherein the output signal amplitude of one of the adjustable gain amplifiers is half of the output signal amplitude of the other of the adjustable gain amplifiers.
In one embodiment of the present invention, three random input signals aligned are input, and the adjustable gain amplifiers are correspondingly three; the output signal amplitudes of the three adjustable gain amplifiers are 1/2,1 and 3/2 respectively.
In an embodiment of the present invention, when the modulator is in an unmodulated working state, a random encoding signal of the modulator outputs a high level signal, and a difference between a voltage of the radio frequency port and a voltage of the signal ground port is 0; when the modulator is in a modulation working state, the random coding signal of the modulator outputs a low-level signal, the voltage of the radio frequency port and the voltage of the signal ground port have a difference value, and the modulation quantity of the modulator on the quantum state random optical signal is the modulation quantity corresponding to the difference value of the voltage of the radio frequency port and the voltage of the signal ground port.
As described above, the modulator driving method and system suitable for quantum state random optical signals of the present invention have the following beneficial effects:
the technical scheme of the invention does not use alternating current coupling capacitance and inductance or bais_t, realizes direct current matching in the whole channel design, can theoretically realize broadband driving from 0Hz (direct current) to more than 10GHz, can meet the broadband driving of 0Hz (direct current) to 10GHz level (the upper frequency limit of the scheme is not limited theoretically), effectively solves the problem of substrate jitter of the existing driving circuit, greatly optimizes the signal quality of driving signals, enables the driving signals to be used in a system with higher signal quality requirement, and improves the performance of the system.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
Fig. 1 shows a schematic block diagram of a prior art modulator driving system suitable for quantum state random optical signals.
Fig. 2 shows a block diagram of the overall principle of the modulator-dynamic system according to the invention, which is suitable for quantum-state random optical signals.
Fig. 3 is a schematic block diagram of an embodiment of a modulator driving system suitable for quantum-state random optical signals according to the present invention.
Fig. 4 shows a schematic block diagram of another embodiment of a modulator driving system suitable for quantum-state random optical signals according to the present invention.
Fig. 5 is a flow chart of a method for driving a modulator suitable for quantum state random optical signals according to the present invention.
Description of element reference numerals
100. Modulator driving system suitable for quantum state random optical signals
110. Input terminal set
1101. Input terminal
1102. Input terminal
1103. Input terminal
110N input terminal
120. Gain-adjustable amplifier group
1201. Gain-adjustable amplifier
1202. Gain-adjustable amplifier
1203. Gain-adjustable amplifier
120N adjustable gain amplifier
130. Broadband resistor network terminal
140. Broadband amplifier
150. Modulator
S110 to S150 steps
Detailed Description
Other advantages and effects of the present invention will become apparent to those skilled in the art from the following disclosure, which describes the embodiments of the present invention with reference to specific examples. The invention may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present invention. It should be noted that the following embodiments and features in the embodiments may be combined with each other without conflict.
Please refer to fig. 2 to fig. 5. It should be understood that the structures, proportions, sizes, etc. shown in the drawings are for illustration purposes only and should not be construed as limiting the invention to the extent that it can be practiced, since modifications, changes in the proportions, or adjustments of the sizes, which are otherwise, used in the practice of the invention, are included in the spirit and scope of the invention which is otherwise, without departing from the spirit or scope thereof. Also, the terms such as "upper," "lower," "left," "right," "middle," and "a" and the like recited in the present specification are merely for descriptive purposes and are not intended to limit the scope of the invention, but are intended to provide relative positional changes or modifications without materially altering the technical context in which the invention may be practiced.
The embodiment aims to provide a modulator driving method and system suitable for quantum state random optical signals, which are used for solving the problems of substrate jitter and poor signal quality caused by insufficient broadband low frequency in the existing modulator driving system suitable for quantum state random optical signals. The principle and the implementation of the modulator driving method and system for quantum state random optical signals according to the present invention will be described in detail below, so that those skilled in the art can understand the modulator driving method and system for quantum state random optical signals according to the present invention without creative effort.
Example 1
As shown in fig. 2, the present embodiment provides a modulator 150 driving system 100 suitable for quantum-state random optical signals, including: an input terminal set 110, an adjustable gain amplifier set 120, a broadband resistive network terminal 130, a broadband amplifier 140, and a modulator 150; wherein the input terminal group 110 includes at least two input terminals: input terminal group 1101 to input terminal group 110N; the set of adjustable gain amplifiers 120 includes at least two adjustable gain amplifiers: the adjustable gain amplifiers 1201 to 120n are positive integers of 2 or more.
The modulator driving system 100 of the present embodiment, which is applicable to a quantum state random optical signal, is described in detail below.
The input terminal group 110 includes at least two input terminals; each input is for inputting an aligned random input signal. In this embodiment, n=2, as shown in fig. 3, the input terminal group 110 includes an input terminal 1101 and an input terminal 1102; input 1101 and input 1102 input two aligned random input signals. Wherein the two random input signals input at input 1101 and input 1102 require signal alignment for alignment, superposition in a subsequent stage resistor network, the alignment method may be, for example, but not limited to, adding a stage of selectable adjustable delay circuits or other methods to each of the two input signals.
The adjustable gain amplifier 120 is correspondingly connected to the input terminal set 110, and the adjustable gain amplifier 120 includes at least two adjustable gain amplifiers, where each adjustable gain amplifier is correspondingly connected to an input terminal one by one, and is configured to amplify a corresponding random input signal, adjust a gain, and output a voltage signal after adjustment, that is, the adjustable gain amplifier 120 is configured to amplify a received signal, and the gain is adjustable, so as to adjust a voltage value finally output to the modulator 150.
In this embodiment, n=2, and the adjustable gain amplifier 120 includes an adjustable gain amplifier 1201 and an adjustable gain amplifier 1202, respectively; wherein the output signal amplitude of one adjustable gain amplifier is half of the output signal amplitude of the other adjustable gain amplifier. For example, the output signal amplitude of the adjustable gain amplifier 1202 is half that of the adjustable gain amplifier 1201.
In this embodiment, the adjustable gain amplifier 1201 and 1202 need to support low frequency input as low as 0Hz (i.e. dc), and the adjustable gain amplifier 1201 and 1202 are preferably adjustable gain amplifiers that can adapt to dc input/output signals.
In this embodiment, the broadband resistive network terminal 130 is connected to the adjustable gain amplifier 1201 and the adjustable gain amplifier 1202, respectively, and is configured to combine the voltage signals output by the adjustable gain amplifier 1201 and the adjustable gain amplifier 1202 and output a combined signal. The broadband resistive network function of the broadband resistive network terminal 130 is to combine and output multiple signals, and the resistive network is characterized by a wide bandwidth, and low frequency can be as low as 0Hz (i.e., direct current).
In this embodiment, the broadband amplifier 140 is connected to the broadband resistive network terminal 130, and is configured to amplify the combined signal to an amplitude required for modulation to form a driving signal.
In this embodiment, the broadband amplifier 140 is used to amplify the input signal to a desired amplitude, and the broadband amplifier 140 also needs to support low frequency input as low as 0Hz (i.e. dc), and the broadband amplifier 140 is preferably a broadband amplifier 140 that can adapt to the dc input/output signal.
In this embodiment, the signal ground port of the modulator 150 is connected to a power supply, the power supply signal is processed by the modulator 150 (for example, through a matching resistor) and then is loaded onto the broadband amplifier 140 through a radio frequency port, and the modulator 150 receives the driving signal output by the broadband amplifier 140 from the radio frequency port and modulates the quantum state random optical signal input into the modulator 150 according to the driving signal.
It can be seen that in this embodiment, the power supply of the wideband amplifier is loaded on the wideband amplifier from the RF port output after the signal ground port of the modulator 150 is connected to the power supply through the matching resistor (typically 50 ohms) of the modulator 150, and the wideband amplifier is powered without using an inductor or bais_t, so as to ensure the low-frequency low-to-0 Hz (i.e. dc) operation capability.
Because the frequency spectrum component of the quantum state random optical signal is very wide, the low end is close to 0Hz (i.e. direct current), the high end is several times of the system frequency, and if the signal is required to be amplified without distortion, the driving scheme needs to cover the low end and the high end. In practical application, the high-end is easy to realize, the low-end is difficult to realize, the low-end signal can be restrained due to the existence of an alternating-current coupling capacitor and an inductor or the bais_T, and the signal distortion after the random optical signal amplification can be caused due to the fact that the broadband low frequency of the driving circuit is not low enough. In the modulator driving system 100 suitable for quantum state random optical signals, the ac coupling capacitor and inductor or bais_t are not used, dc matching is realized in the whole channel design, and a wideband driving circuit from 0Hz (i.e. dc) to more than 10GHz can be theoretically realized.
Therefore, the modulator driving system 100 suitable for quantum state random optical signals in this embodiment can meet the broadband driving (the upper frequency limit of this scheme is not limited in theory) of 0Hz (i.e. direct current) to 10GHz level, perfectly solve the substrate jitter problem of the existing driving circuit, greatly optimize the signal quality of the driving signals, make it possible to use in the system with higher signal quality requirement, and improve the performance of the system.
In this embodiment, the modulator 150 is controlled to modulate the optical signal after receiving the driving signal (RF signal) of the broadband amplifier from the RF port, and the modulator 150 may be a phase modulator or an intensity modulator, or other devices that may be driven by using this type of driving signal.
The modulation amount of the quantum state random optical signal by the modulator 150 is a modulation amount corresponding to a difference value between the voltage of the radio frequency port and the voltage of the signal ground port.
Specifically, in the present embodiment, since the signal ground of the modulator 150 is terminated with the power source, the encoding requirements of the modulator 150 are controlled as follows:
when the modulator 150 is in an unmodulated working state, the random code signal of the modulator 150 outputs a high level signal, and the difference between the voltage of the radio frequency port and the voltage of the signal ground port is 0, that is, when modulation is not needed, the random code signal should output a high level signal, so that the RF end of the modulator 150 is also a power supply voltage, that is, the voltage difference between the RF port voltage and the signal ground port voltage of the modulator 150 is 0. Because the modulator 150 is not modulated most of the time, the voltage difference across the internal resistance of the modulator 150 is 0 most of the time, which reduces the heat generation of the modulator 150 and increases the service life.
When the modulator 150 is in a modulation working state, the random coded signal of the modulator 150 outputs a low-level signal, and the voltage of the radio frequency port and the voltage of the signal ground port have a difference value. That is, when modulation is required, the random code should output low, so that a voltage difference is generated between the RF terminal of the modulator 150 and the signal ground terminal, and the modulator 150 modulates the optical signal passing through.
The implementation of the modulator driving system 100 suitable for quantum-state random optical signals in this embodiment is as follows:
in the field of quantum communication, four random pulse signals of 0,1/2,1,3/2 levels are commonly used to modulate the modulator 150, in this embodiment, two random input signals with aligned signals (aligned to be able to be overlapped at the back end) are given, then the output signal amplitude of one adjustable gain amplifier can be configured to be half of the amplitude of the other adjustable gain amplifier, and then overlapped and output is performed in the back end broadband resistor network, so that after the random input signals are loaded at the input end 1101 and the input end 1102 respectively, four driving signals of 0,1/2,1,3/2 levels can be overlapped to drive the modulator 150, wherein 0,1/2,1,3/2 only represent the quantity relation and not the actual amplitude.
Specifically, the signal amplitude of the adjustable gain amplifier 1202 is 1/2, and the signal amplitude of the adjustable gain amplifier 1201 is 1. When neither the adjustable gain amplifier 1201 nor the adjustable gain amplifier 1202 outputs, the drive signal is a drive signal of 0 level; when the adjustable gain amplifier 1202 with the signal amplitude of 1/2 outputs, the driving signal is a driving signal with the level of 1/2 when the adjustable gain amplifier 1201 does not output; when the adjustable gain amplifier 1201 of signal amplitude 1 outputs, the other adjustable gain amplifier 1202 does not output, the driving signal is a driving signal of 1 level; when both the adjustable gain amplifier 1201 and the adjustable gain amplifier 1202 output, the driving signal is a driving signal of 3/2 level formed by superimposing 1 level and 1/2 level.
The modulator driving system 100 suitable for quantum state random optical signals solves the problem of substrate jitter of the existing driving circuit, greatly optimizes the signal quality of driving signals, enables the driving signals to be used in a system with higher signal quality requirements, and improves the performance of the system.
Example 2
As shown in fig. 2, the present embodiment provides a modulator driving system 100 suitable for quantum-state random optical signals, including: an input terminal set 110, an adjustable gain amplifier set 120, a broadband resistive network terminal 130, a broadband amplifier 140, and a modulator 150; wherein the input terminal group 110 includes at least two input terminals: input terminal group 1101 to input terminal group 110N; the set of adjustable gain amplifiers 120 includes at least two adjustable gain amplifiers: the adjustable gain amplifiers 1201 to 120n are positive integers of 2 or more.
The modulator driving system 100 of the present embodiment, which is applicable to a quantum state random optical signal, is described in detail below.
In this embodiment, the input terminal set 110 includes at least two input terminals; each input is used for inputting an aligned random input signal, in this embodiment, n=3, as shown in fig. 4, and the input group 110 includes an input 1101, an input 1102, and an input 1103; input 1101, input 1102, input 1103 input three paths of aligned random input signals, wherein the three random input signals input by input 1101, input 1102, input 1103 require signal alignment for alignment, superposition in a subsequent stage resistor network, and the alignment method can be, for example, but not limited to, adding a one-stage selectable adjustable delay circuit or other methods to each of the three input signals.
The adjustable gain amplifier 120 is correspondingly connected with the input end group 110 and comprises at least two adjustable gain amplifiers; each adjustable gain amplifier is connected with the input end in a one-to-one correspondence manner, and is used for amplifying the corresponding random input signal, adjusting the gain and outputting the adjusted voltage signal. That is, the adjustable gain amplifier 120 is configured to amplify the received signal, and the gain is adjustable to adjust the voltage value finally output to the modulator 150.
In this embodiment, n=3, and the adjustable gain amplifier 120 includes an adjustable gain amplifier 1201, an adjustable gain amplifier 1202, and an adjustable gain amplifier 1203, respectively; the output signal amplitudes of the adjustable gain amplifier 1201, 1202 and 1203 are 1/2,1,3/2, respectively, wherein 1/2,1,3/2 represent only the number relationship and not the actual amplitude.
In this embodiment, the adjustable gain amplifier 1201, 1202, 1203 are required to support low frequency down to 0Hz (i.e. dc) input, and the adjustable gain amplifier 1201, 1202, 1203 are preferably adjustable gain amplifiers adapted to dc input/output signals.
In this embodiment, the broadband resistive network terminal 130 is connected to the adjustable gain amplifier 1201, the adjustable gain amplifier 1202, and the adjustable gain amplifier 1203, respectively, and is configured to combine the voltage signals output by the adjustable gain amplifier 1201, the adjustable gain amplifier 1202, and the adjustable gain amplifier 1203 and output a combined signal. The broadband resistive network function of the broadband resistive network terminal 130 is to combine and output multiple signals, and the resistive network is characterized by a wide bandwidth, and low frequency can be as low as 0Hz (i.e., direct current).
In this embodiment, the broadband amplifier 140 is connected to the broadband resistive network terminal 130, and is configured to amplify the combined signal to an amplitude required for modulation to form a driving signal.
In this embodiment, the broadband amplifier is used to amplify the input signal to a desired amplitude, and the broadband amplifier 140 is preferably a broadband amplifier 140 that can adapt to the dc input/output signal, and also needs to support low-frequency input as low as 0Hz (i.e., dc).
In this embodiment, the signal ground port of the modulator 150 is connected to a power supply, the power supply signal is processed by the modulator 150 (for example, through a matching resistor) and then is loaded onto the broadband amplifier 140 through a radio frequency port, and the modulator 150 receives the driving signal output by the broadband amplifier 140 from the radio frequency port and modulates the quantum state random optical signal input into the modulator 150 according to the driving signal.
It can be seen that in this embodiment, the power supply of the wideband amplifier is loaded on the wideband amplifier from the RF port output after the signal ground port of the modulator 150 is connected to the power supply through the matching resistor (typically 50 ohms) of the modulator 150, and the wideband amplifier is powered without using an inductor or bais_t, so as to ensure the low-frequency low-to-0 Hz (i.e. dc) operation capability.
Because the spectral components of the quantum state random optical signal are very wide, the low end is close to 0Hz (i.e., direct current), the high end is several times the system frequency, and if signal undistorted amplification is required, the driving scheme needs to cover the low end and the high end. In practical application, the high-side is easy to realize, the low-side is difficult to realize, and the low-side signal can be restrained due to the existence of an alternating-current coupling capacitor and an inductor or bais_t. The low frequency of the broadband of the driving circuit is not low enough, which can lead to signal distortion and poor signal quality after random optical signal amplification. In the modulator driving system 100 suitable for quantum state random optical signals of this embodiment, no ac coupling capacitor and inductor or bais_t are used, dc matching is realized in the whole channel design, and a wideband driving circuit from 0Hz (i.e., dc) to more than 10GHz can be theoretically realized.
Therefore, the modulator driving system 100 suitable for quantum state random optical signals in this embodiment can meet the broadband driving (the upper frequency limit of this scheme is not limited in theory) of 0Hz (i.e. direct current) to 10GHz level, perfectly solve the substrate jitter problem of the existing driving circuit, greatly optimize the signal quality of the driving signals, make it possible to use in the system with higher signal quality requirement, and improve the performance of the system.
In this embodiment, the modulator 150 is controlled to modulate the optical signal after receiving the driving signal (RF signal) of the broadband amplifier from the RF port, and the modulator 150 may be a phase modulator or an intensity modulator, or other devices that may be driven by using this type of driving signal.
The modulation amount of the quantum state random optical signal by the modulator 150 is a modulation amount corresponding to a difference value between the voltage of the radio frequency port and the voltage of the signal ground port.
Specifically, in the present embodiment, since the signal ground of the modulator 150 is terminated with the power source, the encoding requirements of the modulator 150 are controlled as follows:
when the modulator 150 is in an unmodulated working state, the random code signal of the modulator 150 outputs a high level signal, and the difference between the voltage of the radio frequency port and the voltage of the signal ground port is 0, that is, when modulation is not needed, the random code signal should output a high level signal, so that the RF end of the modulator 150 is also a power supply voltage, that is, the voltage difference between the RF port voltage and the signal ground port voltage of the modulator 150 is 0. Because the modulator 150 is not modulated most of the time, the voltage difference across the internal resistance of the modulator 150 is 0 most of the time, which reduces the heat generation of the modulator 150 and increases the service life.
When the modulator 150 is in a modulation working state, the random coded signal of the modulator 150 outputs a low-level signal, and the voltage of the radio frequency port and the voltage of the signal ground port have a difference value. That is, when modulation is desired, the random code output should be low, so that there is a voltage differential between the RF side of modulator 150 and the signal ground, and modulator 150 modulates the optical signal passing through.
In a quantum communication system, the amplitude jitter value of the driving signal of the modulator 150 is a key index of the system, so that the error rate of the system is directly affected, and the system performance can be obviously improved by reducing the amplitude jitter value of the driving signal of the modulator 150. Through theoretical analysis and experimental tests, when the 1/2 voltage and the 1 voltage are used for superposition to generate the 3/2 voltage in the embodiment 1, the amplitude jitter of the 3/2 voltage generates further deterioration on the basis of the 1/2 voltage and the 1 voltage jitter, namely, the amplitude jitter of the 1/2 voltage and the 1 voltage is superposed while signals are superposed, so that the amplitude jitter of the 3/2 voltage is larger, and the overall performance of the system is reduced.
The implementation of the modulator driving system 100 suitable for quantum-state random optical signals in this embodiment is as follows:
in this embodiment, the input 1101, the input 1102 and the input 1103 provide random input signals with aligned three signals, and the adjustable gain amplifier 1201, 1202 and 1203 are adjusted to generate 1/2,1,3/2 voltages respectively. The voltage of each of the adjustable gain amplifier 1201, 1202 and 1203 is 0 when none of them is generated, and one of the three paths of the adjustable gain amplifier 1201, 1202 and 1203 can generate 1/2,1,3/2 voltages, so that four driving signals of 0,1/2,1,3/2 levels can be generated for driving the modulator 150. Therefore, the embodiment avoids the problem of 3/2 voltage amplitude jitter degradation caused when 1/2 voltage and 1 voltage are overlapped to generate 3/2 voltage, generates 3/2 voltage with better signal quality, greatly optimizes the signal quality of a driving signal and improves the performance of a system.
Example 3
The embodiment provides a modulator driving method suitable for a quantum state random optical signal, as shown in fig. 5, including:
step S110, inputting at least two paths of aligned random input signals;
step S120, amplifying the input signal through at least two adjustable gain amplifiers 120, adjusting the gain and outputting the adjusted voltage signal;
step S130, the broadband resistance network terminal 130 is used for combining the output voltage signals and outputting a combined signal;
step S140, amplifying the combined signal to the amplitude required by modulation through a broadband amplifier 140 to form a driving signal;
step S150, connecting a signal ground port of the modulator 150 to a power supply, processing a power supply signal by the modulator 150, loading the processed power supply signal onto the broadband amplifier 140 through a radio frequency port, receiving the driving signal output by the broadband amplifier 140 from the radio frequency port by the modulator 150, and modulating a quantum state random optical signal input into the modulator 150 according to the driving signal.
In this embodiment, when the modulator 150 is in the non-modulated working state, the random encoded signal of the modulator 150 outputs a high level signal, and the difference between the voltage of the radio frequency port and the voltage of the signal ground port is 0; when the modulator 150 is in a modulation working state, the random code signal of the modulator 150 outputs a low-level signal, a difference exists between the voltage of the radio frequency port and the voltage of the signal ground port, and the modulation amount of the quantum state random optical signal by the modulator 150 is the modulation amount corresponding to the difference between the voltage of the radio frequency port and the voltage of the signal ground port.
The method in this example can be performed by the system of example 1: through two inputs: input 1101 and input 1102 input two random input signals aligned, and the set of adjustable gain amplifiers 120 respectively comprises two adjustable gain amplifiers: an adjustable gain amplifier 1201 and an adjustable gain amplifier 1202; wherein the output signal amplitude of one adjustable gain amplifier is half of the output signal amplitude of the other adjustable gain amplifier. The implementation principle is the same as that of embodiment 1, and will not be described again here.
The method in this embodiment may also be performed by the system of embodiment 2: through three inputs: input 1101, input 1102, input 1103 input three aligned random input signals, the set of adjustable gain amplifiers 120 comprises three adjustable gain amplifiers, respectively: an adjustable gain amplifier 1201, an adjustable gain amplifier 1202, an adjustable gain amplifier 1203; the output signal amplitudes of the adjustable gain amplifier 1201, 1202 and 1203 are 1/2,1 and 3/2, respectively. The implementation principle is the same as that of embodiment 2, and will not be described again here.
In summary, the technical scheme of the invention does not use an ac coupling capacitor and an inductor or bais_t, realizes dc matching in the whole channel design, can theoretically realize broadband driving from 0Hz (i.e., dc) to more than 10GHz, can meet the broadband driving of 0Hz (i.e., dc) to 10GHz levels (the upper frequency limit of the scheme is not limited theoretically), effectively solves the substrate jitter problem of the existing driving circuit, greatly optimizes the signal quality of driving signals, enables the driving signals to be used in a system with higher signal quality requirements, and improves the performance of the system. Therefore, the invention effectively overcomes various defects in the prior art and has high industrial utilization value.
The above embodiments are merely illustrative of the principles of the present invention and its effectiveness, and are not intended to limit the invention. Modifications and variations may be made to the above-described embodiments by those skilled in the art without departing from the spirit and scope of the invention. Accordingly, it is intended that all equivalent modifications and variations of the invention be covered by the claims of this invention, which are within the skill of those skilled in the art, be included within the spirit and scope of this invention.
Claims (8)
1. A modulator drive system for a quantum state random optical signal, comprising:
an input terminal group comprising three input terminals for inputting three paths of aligned random input signals;
an adjustable gain amplifier group comprising three adjustable gain amplifiers; each adjustable gain amplifier is connected with the input end in a one-to-one correspondence manner, and is used for amplifying and adjusting the gain of the corresponding random input signal and outputting the adjusted voltage signal; the output signal amplitudes of the three adjustable gain amplifiers are 1/2,1 and 3/2 respectively;
the broadband resistor network terminal is in communication connection with the adjustable gain amplifier group and is used for combining the voltage signals output by the adjustable gain amplifiers and outputting combined signals;
the broadband amplifier is in communication connection with the broadband resistance network terminal and is used for amplifying the combined signal to the amplitude required by modulation to form a driving signal;
the signal ground port of the modulator is connected with a power supply, and a power supply signal is processed by the modulator and then is loaded on the broadband amplifier through the radio frequency port; the modulator receives the driving signal from the radio frequency port and modulates the quantum state random optical signal input into the modulator according to the driving signal.
2. The modulator driving system for a quantum state random optical signal according to claim 1, wherein the modulation amount of the quantum state random optical signal by the modulator is a modulation amount corresponding to a difference between the voltage of the radio frequency port and the voltage of the signal ground port.
3. The modulator driving system for quantum state random optical signal according to claim 2, wherein the random encoded signal output of the modulator is a high level signal when in an unmodulated operation state, and the difference between the voltage of the radio frequency port and the voltage of the signal ground port is 0; when in a modulation working state, the random coding signal of the modulator is output as a low-level signal, and the voltage of the radio frequency port and the voltage of the signal ground port have a difference value.
4. The modulator driving system for quantum-state random optical signals according to claim 1, wherein the adjustable gain amplifier is an adjustable gain amplifier adapted to a dc input/output signal; the broadband amplifier is a broadband amplifier which can adapt to direct current input and output signals.
5. A modulator driving method suitable for quantum state random optical signals, characterized in that the modulator driving method suitable for quantum state random optical signals comprises:
inputting three paths of aligned random input signals;
amplifying the input signal by three adjustable gain amplifiers, adjusting the gain and outputting the adjusted voltage signal; the output signal amplitudes of the three adjustable gain amplifiers are 1/2,1 and 3/2 respectively;
the output voltage signals are combined through a broadband resistance network terminal, and a combined signal is output;
amplifying the combined signal to the amplitude required by modulation through a broadband amplifier to form a driving signal;
connecting a signal ground port of a modulator with a power supply, processing a power supply signal by the modulator, loading the power supply signal onto the broadband amplifier through a radio frequency port, and receiving the driving signal output by the broadband amplifier from the radio frequency port by the modulator and modulating a quantum state random optical signal input into the modulator according to the driving signal.
6. The method according to claim 5, wherein the modulation amount of the quantum state random optical signal by the modulator is a modulation amount corresponding to a difference between the voltage of the radio frequency port and the voltage of the signal ground port.
7. The method of claim 6, wherein the random coded signal of the modulator outputs a high level signal when in an unmodulated operating state, and the difference between the voltage of the rf port and the voltage of the signal ground port is 0; when in a modulation working state, the random coding signal of the modulator is output as a low-level signal, and the voltage of the radio frequency port and the voltage of the signal ground port have a difference value.
8. The method of claim 5, wherein the adjustable gain amplifier is an adjustable gain amplifier adapted to a dc input/output signal; the broadband amplifier is a broadband amplifier which can adapt to direct current input and output signals.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102739394A (en) * | 2012-06-07 | 2012-10-17 | 中国科学技术大学 | Light quantum phase modulating system |
| CN203313201U (en) * | 2013-04-03 | 2013-11-27 | 安徽问天量子科技股份有限公司 | High-speed optical-phase modulator drive device used for quantum-secret-key distribution system |
| JP2017173385A (en) * | 2016-03-18 | 2017-09-28 | 日本電信電話株式会社 | Optical modulator |
| CN107425920A (en) * | 2017-03-24 | 2017-12-01 | 安徽问天量子科技股份有限公司 | A kind of modulation drive system of four level quantum phases at a high speed |
| JP2018092100A (en) * | 2016-12-07 | 2018-06-14 | 日本電信電話株式会社 | Optical transmitter |
| CN209072502U (en) * | 2018-11-19 | 2019-07-05 | 科大国盾量子技术股份有限公司 | Modulator drive system suitable for the random optical signal of quantum state |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6701115B2 (en) * | 2017-04-12 | 2020-05-27 | 日本電信電話株式会社 | Optical transmitter |
-
2018
- 2018-11-19 CN CN201811372698.4A patent/CN110635851B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102739394A (en) * | 2012-06-07 | 2012-10-17 | 中国科学技术大学 | Light quantum phase modulating system |
| CN203313201U (en) * | 2013-04-03 | 2013-11-27 | 安徽问天量子科技股份有限公司 | High-speed optical-phase modulator drive device used for quantum-secret-key distribution system |
| JP2017173385A (en) * | 2016-03-18 | 2017-09-28 | 日本電信電話株式会社 | Optical modulator |
| JP2018092100A (en) * | 2016-12-07 | 2018-06-14 | 日本電信電話株式会社 | Optical transmitter |
| CN107425920A (en) * | 2017-03-24 | 2017-12-01 | 安徽问天量子科技股份有限公司 | A kind of modulation drive system of four level quantum phases at a high speed |
| CN209072502U (en) * | 2018-11-19 | 2019-07-05 | 科大国盾量子技术股份有限公司 | Modulator drive system suitable for the random optical signal of quantum state |
Non-Patent Citations (1)
| Title |
|---|
| Electro-Optical Co-Design to Minimize Power Consumption of a 32 GBd Optical IQ-Transmitter Using InP MZ-Modulators;N. Wolf等;CSICS 2015;1-4 * |
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