CN111208690A - Optical digital-to-analog converter, signal processing system and photonic neural network chip - Google Patents
Optical digital-to-analog converter, signal processing system and photonic neural network chip Download PDFInfo
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- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
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- G06N3/0675—Physical realisation, i.e. hardware implementation of neural networks, neurons or parts of neurons using optical means using electro-optical, acousto-optical or opto-electronic means
Abstract
The application provides an optics digital-to-analog converter, signal processing system and photon neural network chip, wherein, optics digital-to-analog converter includes: the photoelectric converter is used for receiving the N-bit digital signals transmitted by the electric chip, respectively converting the data of each bit in the digital signals into corresponding optical signals, and then parallelly outputting N paths of optical signals corresponding to the digital signals, wherein N is a positive integer; the optical attenuator group is used for receiving N-1 paths of optical signals in the N paths of optical signals and attenuating the N-1 paths of optical signals to obtain N-1 paths of attenuated optical signals; and the adder is used for adding the N-1 paths of attenuated optical signals and one path of optical signals except the N-1 paths of optical signals in the N paths of optical signals to obtain the analog optical signals. The optical attenuator group is used for attenuating optical signals, after the optical signals pass through the optical digital-to-analog converter, the analog quantity of the output analog optical signals is in direct proportion to the digital quantity of the input digital signals, and conversion from the digital quantity to the analog quantity is achieved.
Description
Technical Field
The application relates to the technical field of photon calculation, in particular to an optical digital-to-analog converter, a signal processing system and a photonic neural network chip.
Background
A digital-to-analog converter is a device that converts a digital signal into an analog signal, and in many electronic circuits, the signal is stored and transmitted in a digital manner, and the digital-to-analog converter can convert such a signal into an analog signal so that the signal can be recognized by the outside (including a person or an external device). Digital-to-analog converters are bridges connecting the analog world and the digital world, and in the current information explosion era, in order to meet the requirements of users on mass data and the requirements of various fields on the quality of acquired information, digital-to-analog converters are continuously developed in the direction of higher speed and higher precision. However, at present, three key indexes of bandwidth, sampling rate and quantization precision of a digital-to-analog converter based on an electronic technology are all close to physical limits, and further improvement on an original framework is difficult to realize. Meanwhile, high-precision and high-speed digital-to-analog converters are limited in foreign countries, and the price of the high-speed digital-to-analog converters and analog-to-digital converters with frequency reaching GHz in the market is very expensive.
As a technology completely different from electronic computation, optical computation uses photons as an information processing carrier, relies on optical hardware rather than electronic hardware, and replaces electrical computation with optical computation, so that highly complex computation tasks can be rapidly and parallelly processed. In the process of the cooperation of the photonic chip and the electronic chip, the technical problem of converting the digital signal of the electronic chip into the analog optical signal required by the photonic chip needs to be faced, and the optical digital-to-analog converter suffers from technical bottleneck because the amplifier is difficult to be made on the silicon substrate.
Disclosure of Invention
An object of the embodiments of the present application is to provide an optical digital-to-analog converter, a signal processing system, and a photonic neural network chip, which utilize an optical attenuator to implement an optical digital-to-analog conversion function, thereby overcoming a rate bottleneck of an electrical domain digital-to-analog converter, and significantly improving a processing rate of the optical domain digital-to-analog converter.
In a first aspect, an embodiment of the present application provides an optical digital-to-analog converter, including: the photoelectric converter is used for receiving N-bit digital signals transmitted by the electric chip, respectively converting data of each bit in the digital signals into corresponding optical signals, and then parallelly outputting N paths of optical signals corresponding to the digital signals, wherein N is a positive integer; the optical attenuator group is used for receiving N-1 paths of optical signals in the N paths of optical signals and attenuating the N-1 paths of optical signals to obtain N-1 paths of attenuated optical signals; and the adder is used for adding the N-1 paths of attenuated optical signals and one path of optical signals except the N-1 paths of optical signals in the N paths of optical signals to obtain analog optical signals.
In the above scheme, the optical signal is attenuated by the optical attenuator group, and in the optical digital-to-analog converter, the analog quantity of the output analog optical signal is proportional to the digital quantity of the input digital signal, so that the conversion from the digital quantity to the analog quantity is realized. Because the optical digital-to-analog converter indirectly amplifies signals based on the optical attenuator, compared with an amplifier, the optical digital-to-analog converter can effectively reduce power consumption, and meanwhile, compared with a digital-to-analog converter based on an electronic technology, the optical digital-to-analog converter is higher in precision and speed and lower in cost.
In one embodiment of the first aspect, the optical attenuator group includes M optical attenuators, and the N-bit digital signal has the following relationship with the number M of optical attenuators: n-1 is less than or equal to M, wherein each optical attenuator only processes one path of optical signal, and M is a positive integer.
The processing algorithm in the electrical chip should control the number of bits of the digital signal output to the optical-to-electrical converter to be equal to or less than M +1 so that the number of the digital signal and the number of the optical attenuators satisfy the above relationship, and the M optical attenuators can attenuate at most M optical signals.
In one embodiment of the first aspect, the attenuation ratio of each optical attenuator in the optical attenuator group is different from each other, and the attenuation ratio between the plurality of attenuators is 2-1Wherein the minimum attenuation ratio of the optical attenuator is 1/2.
In one embodiment of the first aspect, the photoelectric converter comprises M +1 output terminals; the M output ends of the photoelectric converter are connected with the M optical attenuators in the optical attenuator group one by one, wherein the M output ends of the photoelectric converter are respectively the output ends from the second high bit data to the lowest bit data in the digital signal.
In one embodiment of the first aspect, the output of the second high bit data to the lowest bit data in the photoelectric converter is connected in sequence with the optical attenuator having the largest attenuation ratio to the smallest attenuation ratio.
In an implementation manner of the first aspect, one output terminal of the optical-to-electrical converter except the M output terminals is connected to the adder, and the output terminal connected to the adder is configured to output one optical signal of the N optical signals except the N-1 optical signals to the adder.
In one embodiment of the first aspect, the output terminal of the photoelectric converter connected to the adder is an output terminal of highest bit data in the digital signal.
In an embodiment of the first aspect, M output terminals of the photoelectric converter and M optical attenuators of the optical attenuator group, output terminals of the photoelectric converter except the M output terminals and the adder, and the M optical attenuators and the adder are connected through silicon waveguides.
M +1 independent transmission optical paths are formed in the optical digital-to-analog converter through silicon waveguides, and each optical path transmits one optical signal.
In a second aspect, an embodiment of the present application provides a signal processing system, including: an electrical chip, an optical digital-to-analog converter and a photonic chip as described in the first aspect; the electrical chip is used for sending a digital signal carrying information to the optical digital-to-analog converter, the optical digital-to-analog converter is used for receiving the digital signal, converting the digital signal into an analog optical signal, and then outputting the analog optical signal to the photonic chip, and the photonic chip is used for performing operation based on the information carried in the analog optical signal.
In a third aspect, an embodiment of the present application provides a photonic neural network chip, where the photonic neural network chip is provided with a processing device and the optical digital-to-analog converter according to the first aspect, the optical digital-to-analog converter is configured to receive a digital signal transmitted from an electrical chip, convert the digital signal into an analog optical signal, and send the analog optical signal to the processing device, and the processing device is configured to perform an operation based on information carried in the analog optical signal.
The optical digital-to-analog converter can be integrated on a photonic chip and integrated into an independent microchip together with the processing device to form a photonic neural network chip so as to realize the function of on-chip digital-to-analog conversion. The optical digital-to-analog converter is used as the front end of the photonic neural network chip and is used for preprocessing an input digital signal.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments of the present application will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and that those skilled in the art can also obtain other related drawings based on the drawings without inventive efforts.
FIG. 1 is a simplified diagram of a prior art digital-to-analog converter based on electronics;
fig. 2 is a schematic structural diagram of an optical digital-to-analog converter according to an embodiment of the present disclosure;
fig. 3 is another schematic structural diagram of an optical digital-to-analog converter according to an embodiment of the present disclosure;
fig. 4 is a schematic structural diagram of an optical digital-to-analog converter according to an embodiment of the present disclosure;
FIG. 5 is a schematic diagram of a photonic neural network chip provided in an embodiment of the present application;
fig. 6 is a schematic diagram of a signal processing system according to an embodiment of the present application.
Icon: 110-a photoelectric converter; 120-a group of optical attenuators; 130-an adder; 100-an optical digital-to-analog converter; 210-a processing device; 310-an electrical chip; 320-photonic chip.
Detailed Description
The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application.
Photon calculation uses light to provide calculation power, can bring apparent promotion to calculation power, simultaneously, because replace electronic signal with optical signal on the silicon chip to transmit data, can promote signal transmission speed greatly, reduce the consumption. In view of the great advantages of photonic chips in terms of computational rate, power consumption, etc. compared to conventional electronic digital processing chips, and the need for current photonic chips to rely on cooperation with an electrical chip, the present embodiment thus provides an optical digital-to-analog converter. The electrical chip processes digital signals, and the photonic chip processes analog optical signals, so that signal transmission between the electrical chip and the photonic chip needs to convert between digital signals and analog optical signals.
In order to facilitate understanding of the technical solution, a digital-to-analog converter based on electronic technology in the prior art is briefly introduced. Fig. 1 shows the basic principle of an electronic-based digital-to-analog converter, the input of which receives an n-bit binary digital signal, where msb (most Significant bit) refers to the most Significant bit (hereinafter also referred to as the most Significant bit) and has the highest weight 2n-1LSB (LSB) (Least Significant bit) refers to the least Significant bit (hereinafter also referred to as the least Significant bit) and has the lowest weight of 20. In the received n-bit digital signal, the data from the high bit to the low bit are: dn-1、dn-2、…、d1、d0. For any one n-bit binary number DnThey can be expressed by the following expansion by weight: dn=dn-1×2n-1+dn-2×2n-2+…+d1×21+d0×20Wherein 2 isn-1、2n-2、…、21、20Respectively, the weights of the corresponding data. Digital-to-analog converter receiving digital signal DnThen, each bit of data is converted into corresponding analog quantity according to the weight value, then all the analog quantities are added, the sum is the analog quantity corresponding to the digital quantity, and the final output analog quantity is: v. ofo=K*(dn-1×2n-1+dn-2×2n-2+…+d1×21+d0×20)=K*DnThe output analog voltage is proportional to the input digital signal DnThereby realizing conversion from digital quantity to analog quantity.
Fig. 2 shows a schematic structural diagram of the optical digital-to-analog converter in this embodiment. As shown in fig. 2, the optical digital-to-analog converter includes: the optical fiber module comprises an optical-to-electrical converter 110, an optical attenuator group 120 and an adder 130, wherein an output of the optical-to-electrical converter 110 is connected with an input of the optical attenuator group 120, an output of the optical attenuator group 120 is connected with an input of the adder 130, one output of the optical-to-electrical converter 110 is connected with an input of the adder 130, an input of the optical-to-electrical converter 110 is used as an input of an optical digital-to-analog converter, and an output of the adder 130 is used as an output of the. The photoelectric converter 110 is used for performing photoelectric conversion, and converting an input electrical signal carrying information into a corresponding optical signal carrying information; the optical attenuator group 120 is configured to perform optical attenuation on the power of an input optical signal by a predetermined amount in the transmission process of the optical signal, where the predetermined amount is related to an attenuation ratio of optical attenuators in the optical attenuator group, in this embodiment, the optical attenuator may be any optical device capable of achieving optical power attenuation in the prior art, including but not limited to a variable optical attenuator and a fixed optical attenuator, as long as the optical attenuators having the same functions as those described in this embodiment are all applicable to this embodiment, the optical attenuator group 120 includes a plurality of optical attenuators, and the types of the plurality of optical attenuators may be the same or different; the adder 130 is used for adding and superimposing the input multiple optical signals, and combining the multiple optical signals into one optical signal for output.
The optical-to-electrical converter 110 may be connected to the electrical chip, and configured to receive a digital signal transmitted from the electrical chip, for example, a digital signal with N bits, where N is a positive integer, and then perform optical-to-electrical conversion on data of each bit in the N-bit digital signal, convert the data of the corresponding bit into a corresponding optical signal, obtain N paths of optical signals, and output the N paths of optical signals, where N-1 paths of optical signals in the N paths of optical signals are output to the optical attenuator group, and one path of optical signals except the N-1 paths of optical signals in the N paths of optical signals is directly output to the adder. The optical attenuator group 120 is configured to receive the N-1 optical signals output by the optical-to-electrical converter, attenuate each of the N-1 optical signals to obtain N-1 attenuated optical signals, and output the N-1 attenuated optical signals to the adder. The adder 130 is configured to receive one path of optical signal output by the optical-to-electrical converter and N-1 paths of attenuated optical signals output by the optical attenuator group, and add the one path of optical signal output by the optical-to-electrical converter and the N-1 paths of attenuated optical signals output by the optical attenuator group to obtain one path of analog optical signal. Therefore, the digital signal output by the electric chip sequentially passes through the photoelectric converter, the optical attenuator group and the adder, and digital-to-analog conversion from the digital signal to the analog optical signal is realized. The output end of the adder can be connected with a photonic chip, the adder is used for outputting the analog optical signal obtained after conversion to the photonic chip, and the photonic chip can carry out operation based on the information carried in the analog optical signal.
In a specific embodiment, the optical attenuator group includes a plurality of optical attenuators, the number of the plurality of optical attenuators is M, and the N-bit digital signal has the following relationship with the number of the optical attenuators: n-1 is less than or equal to M, and in principle, the processing algorithm in the electric chip should control the bit number of the digital signal output to the photoelectric converter to be less than or equal to M +1, wherein M is a positive integer. The photoelectric converter outputs N-1 paths of optical signals to the optical attenuator group, N-1 optical attenuators in the optical attenuator group (M optical attenuators) respectively perform attenuation processing on the N-1 paths of optical signals, and each optical attenuator only performs processing on one path of optical signals. In the M optical attenuators, the attenuation ratio of each optical attenuator is different from each other, and the attenuation ratio between the plurality of attenuators is 2-1Wherein the minimum attenuation ratio of the optical attenuator is 1/2, that is, the attenuation ratio of the M optical attenuatorsThe proportion is from big to small: 1/2, 1/4, 1/8, …, 1/2(M-1)、1/2MTherefore, the attenuation amplitude of each optical signal in the N-1 optical signals is different.
Fig. 3 shows a schematic structural diagram of a specific optical digital-to-analog converter, and as shown in fig. 3, the optical attenuator group 120 includes: the optical attenuator 1, the optical attenuators 2 and …, the optical attenuator M-1 and the optical attenuator M, wherein the photoelectric converter 110 comprises M +1 output ends; the M output terminals of the optical-to-electrical converter 110 are connected to the M optical attenuators of the optical attenuator group 120 one by one, and the remaining one output terminal of the optical-to-electrical converter 110 except the M output terminals is directly connected to the adder 130. After receiving the N-bit digital signals, the photoelectric converter outputs N paths of optical signals through N output ends of M +1 output ends, each path of optical signal is obtained by performing photoelectric conversion on data of one bit in the digital signals, among the N paths of optical signals, N-1 paths of optical signals are respectively output to an optical attenuator correspondingly connected with the output end, and the rest paths of optical signals are output to the adder; each optical attenuator receives one path of optical signal respectively, then attenuates the received optical signal according to the attenuation proportion corresponding to the optical attenuator, and N-1 paths of optical signals are attenuated by 1/2, 1/4, 1/8, … and 1/2 respectively(N-2)、1/2(N-1)And (4) doubling. In the above connection relationship, M output terminals of the photoelectric converter 110 connected to the M optical attenuators are output terminals of the second highest bit data to the lowest bit data in the digital signal, respectively, and one output terminal of the photoelectric converter connected to the adder is an output terminal of the highest bit data in the digital signal. The output end of the lowest bit data here means an output end for outputting the optical signal after the photoelectric converter converts the data of the lowest bit in the digital signal into the corresponding optical signal, and the explanations of the other output ends are the same. It should be noted that the output end of the second high bit data to the lowest bit data in the photoelectric converter is connected with the optical attenuator with the maximum attenuation ratio to the minimum attenuation ratio in sequence. For example, the output terminal of the second high bit data in the photoelectric converter is connected with an optical attenuator with an attenuation ratio of 1/2, and the photoelectric conversion is carried outThe output end of the third high bit data in the converter is connected with an optical attenuator with the attenuation ratio of 1/4, and so on, the output end of the lowest bit data in the photoelectric converter is connected with an optical attenuator with the attenuation ratio of 1/2MAre connected to the optical attenuator.
It should be noted that the number M of optical attenuators in the optical attenuator group is determined during manufacturing, that is, after the optical digital-to-analog converter is manufactured, M is a fixed value, while the number of bits of the N-bit digital signal received by the optical digital-to-analog converter varies depending on the size of the information transmitted by the electrical chip to the photonic chip, so that during use, the number of optical attenuators actually used is determined according to a specific digital signal and may be smaller than the number M of optical attenuators, and for digital signals of different bits, the number of optical attenuators used is different, and for a certain digital signal, the number of optical attenuators required is 1 less than the number of bits of the digital signal. In use, for the unused optical attenuators among the M optical attenuators, the outputs of the photoelectric converters respectively connected to the optical attenuators do not output optical signals, so that the optical attenuators do not work in the current digital-to-analog conversion process.
Fig. 4 shows a structural schematic diagram of a specific optical digital-to-analog converter, and for convenience of description, N =6 and M =5 are taken as examples in fig. 4, that is, N = M +1, that is, 5 optical attenuators are used to perform digital-to-analog conversion on a 6-bit digital signal. However, it should be understood that the number M of the optical attenuator groups may be other values, for example, 10, 20, 30, etc., the structure shown in fig. 4 is only an example and should not be understood as a limitation to the technical solution of the present embodiment, and when M =5, the N-bit digital signal received by the photoelectric converter may also be 3 bits, 4 bits, etc. The 5 optical attenuators shown in fig. 4 are 1/2 attenuator, 1/4 attenuator, 1/8 attenuator, 1/16 attenuator and 1/32 attenuator, and their corresponding attenuation ratios are: 1/2, 1/4, 1/8, 1/16, 1/32.
In a specific embodiment, the electrical chip outputs a 6-bit digital signal, for example 010101, to the optical-to-electrical converter; the photoelectric converter receives the digital signal to obtain data of each bit in the digital signal, and the data of each bit in the digital signal sequentially comprises the following bits from the highest bit to the lowest bit: 0. 1, 0, 1, 0 and 1, wherein, according to the sequence from left to right, the first 0 is the data of the highest bit, the second 1 to the last 1 are the data of the second highest bit to the data of the lowest bit, then the data of each bit is subjected to photoelectric conversion, 6 paths of optical signals are output simultaneously through 6 output ends, wherein, the output end of the highest bit (used for outputting the optical signal corresponding to the first 0) is directly connected with the adder and is not connected with the optical attenuator, and the output optical signal does not pass through the optical attenuator, therefore, the path of optical signal is not attenuated; the output terminal of the second bit data (for outputting the optical signal corresponding to 1 of the second bit) is connected to the optical attenuator with the maximum attenuation ratio (the attenuation ratio is 1/2), so the optical signal corresponding to the second high bit data will be attenuated by 1/2 times; an output end (for outputting the optical signal corresponding to 0 of the third bit) of the third bit data is connected to an optical attenuator with an attenuation ratio of 1/4, so that the optical signal corresponding to the third bit data is attenuated by 1/4 times; an output end (for outputting the optical signal corresponding to 1 of the fourth bit data) of the fourth bit data is connected with an optical attenuator with an attenuation ratio of 1/8, so that the optical signal corresponding to the fourth bit data is attenuated by 1/8 times; an output end (for outputting an optical signal corresponding to 0 of the fifth bit) of the fifth bit data is connected to an optical attenuator with an attenuation ratio of 1/16, so that the optical signal corresponding to the fifth bit data is attenuated by 1/16 times; an output terminal of the sixth bit data (for outputting the optical signal corresponding to the last 1) is connected to the optical attenuator with the attenuation ratio of 1/32, so that the optical signal corresponding to the sixth bit data is attenuated by 1/32 times.
The input of the adder is connected with the outputs of the 5 optical attenuators and one output of the photoelectric converter, and the input of the adder comprises: the optical signal corresponding to the highest bit is not attenuated, the optical signal corresponding to the second bit is attenuated by 1/2 times, the optical signal corresponding to the third bit is attenuated by 1/4 times, the optical signal corresponding to the fourth bit is attenuated by 1/8 times, the optical signal corresponding to the fifth bit is attenuated by 1/16 times, and the optical signal corresponding to the sixth bit is attenuated by 1/32 times. The adder adds the received multiple paths of optical signals, and finally, the optical signals are combined to obtain a needed path of analog optical signal.
As can be seen from the above example, the 6-bit digital signal D output by the electrical chip to the photoelectric converter6The expansion by weight of (1) is: d6=d5×25+d4×24+d3×23+d2×22+d1×21+d0×20The analog optical signal y output from the adder is processed by photoelectric conversion of the photoelectric converter, attenuation of the optical attenuator group, and superposition of the adder on the 6-bit digital signaloCan be expressed as:
yo=d5×20+d4×2-1+d3×2-2+d2×2-3+d1×2-4+d0×2-5
=2-5*(d5×25+d4×24+d3×23+d2×22+d1×21+d0×20)
=K’*D6
it can be seen that after passing through the optical DAC, the analog quantity of the output optical signal is also proportional to the input digital signal D6Thereby realizing conversion from digital quantity to analog quantity.
In the above description of the present invention, taking N =6 and M =5 as an example, when the number of bits of the digital signal extends from 6 bits to another number of bits and the number M of the optical attenuators extends from 5 to another number, the analog optical signal y output by the optical digital-to-analog converter is outputoIs always proportional to the digital quantity of the digital signal received by the optical digital-to-analog converter. In fig. 4, when N is less than M +1, for example, at M =5 and N =2, the remaining four optical attenuators except the 1/2 attenuator do not receive the optical signal, so that the remaining four optical attenuatorsThe optical attenuator is not active.
Based on the optical digital-to-analog converter, the embodiment provides a photonic neural network chip, and the optical digital-to-analog converter can be integrated on a photonic chip to realize an on-chip digital-to-analog conversion function. FIG. 5 shows a simple schematic of the photonic neural network chip, which includes: the output of the optical digital-to-analog converter 100 is connected with the input of the processing device 210, the photonic neural network chip receives the digital signal transmitted from the electrical chip through the optical digital-to-analog converter 100, converts the received digital signal into an analog optical signal through the optical digital-to-analog converter 100, and then transmits the converted analog optical signal to the processing device 210, the analog optical signal and the digital signal output by the electrical chip carry the same information, and the processing device 210 performs operation based on the information carried in the analog optical signal.
In this embodiment, the optical digital-to-analog converter on the photonic neural network chip is the same as the optical digital-to-analog converter described in the previous embodiment, and the specific structure thereof can refer to the detailed description of the previous embodiment, which is not described herein again; the processing device on the photon neural network chip can be used for processing an artificial intelligence algorithm and calculating based on information carried in the analog optical signal, the processing device can be composed of a specific optical device, the specific hardware structure of the processing device can be the same as or similar to that of the existing photon chip, and the optical digital-to-analog converter is used as the front end of the photon neural network chip and used for preprocessing the input digital signal.
In the optical digital-to-analog converter, M output ends in the photoelectric converter are connected with M optical attenuators in the optical attenuator group, output ends except the M output ends in the photoelectric converter are connected with the adder, and the M optical attenuators are connected with the adder through silicon waveguides on a chip, M +1 independent transmission light paths are formed in the optical digital-to-analog converter through the silicon waveguides, and each light path transmits one path of optical signals.
After the photonic neural network chip receives an N-bit digital signal transmitted by the electric chip, the digital signal is subjected to 1-bit photoelectric conversion through the photoelectric converter and is converted into N paths of analog optical signals, N-1 optical attenuators in M optical attenuators attenuate optical signals corresponding to different bit data in proportion, and then the attenuated N-1 paths of optical signals and one path of non-attenuated optical signals are superposed through the adder. Since the silicon substrate is difficult to be used as an amplifier on a chip, the present embodiment realizes amplification of optical signals of different bit data by opposite-direction attenuation, and further realizes conversion from digital quantity to analog quantity, wherein different attenuation ratios of the optical attenuator are used to represent weights.
The attenuation in the opposite direction is from the N-bit digital signal DNIt can be seen that the weight of the highest bit should be 2n-1The weight of the lowest bit should be 20The weight of the middle bit is from high to low according to 21The proportional relation of (A) is decreased in turn, and the weight of the highest bit is changed to 2 due to the use of the optical attenuator0The weight of the lowest bit becomes 2-(n-1)The weight of the middle bit is from high to low according to 2-1The proportional relation of the amplifier is decreased gradually in sequence, so that the finally output analog quantity has a proportional relation with the input digital quantity, the function of the amplifier is indirectly realized, the power consumption can be effectively reduced, and if the amplifier is used for amplifying the optical signal, the extra power consumption is increased.
Further, an embodiment of the present application also provides a signal processing system, as shown in fig. 6, where the signal processing system includes: the optical digital-to-analog converter 100 is connected between the electric chip 310 and the photonic chip 320 in series and serves as a conversion bridge of a digital signal and an analog optical signal; the electrical chip 310 is configured to send a digital signal carrying information to the optical digital-to-analog converter 100, the optical digital-to-analog converter 100 is configured to receive the digital signal, convert the digital signal into an analog optical signal, and output the analog optical signal to the photonic chip 320, where the photonic chip 320 is configured to perform an operation based on the information carried in the analog optical signal. In this embodiment, the specific structure of the optical digital-to-analog converter 100 may refer to the detailed description of the previous embodiment, and the photonic chip 320 may be any photonic chip based on photonic technology in the prior art, and is used for performing the massive parallel computation of artificial intelligence.
To sum up, the optical digital-to-analog converter provided in the embodiment of the present application uses the optical attenuator to perform opposite-direction attenuation on the optical signal, so as to indirectly amplify the signal, thereby solving the technical bottleneck problem suffered by the optical digital-to-analog converter, and the precision and the speed of the optical digital-to-analog converter are higher than those of the electronic digital-to-analog converter, and the cost price is lower than that of the electronic digital-to-analog converter. The optical digital-to-analog converter can be integrated with the processing device (formed by other optical devices) into a separate microchip to form a photonic neural network chip, so that the photonic chip integrates the function of digital-to-analog conversion on the chip.
In the embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other ways. The above-described embodiments of the apparatus are merely illustrative, and for example, the division of the units is only one logical division, and there may be other divisions when actually implemented, and for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection of devices or units through some communication interfaces, and may be in an electrical, mechanical or other form.
In addition, units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.
Furthermore, the functional modules in the embodiments of the present application may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.
In this document, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions.
The above description is only an example of the present application and is not intended to limit the scope of the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims (10)
1. An optical digital-to-analog converter, comprising:
the photoelectric converter is used for receiving N-bit digital signals transmitted by the electric chip, respectively converting data of each bit in the digital signals into corresponding optical signals, and then parallelly outputting N paths of optical signals corresponding to the digital signals, wherein N is a positive integer;
the optical attenuator group is used for receiving N-1 paths of optical signals in the N paths of optical signals and attenuating the N-1 paths of optical signals to obtain N-1 paths of attenuated optical signals;
and the adder is used for adding the N-1 paths of attenuated optical signals and one path of optical signals except the N-1 paths of optical signals in the N paths of optical signals to obtain analog optical signals.
2. The digital-to-analog converter according to claim 1, wherein the optical attenuator group comprises M optical attenuators, and the N-bit digital signal has the following relationship with the number M of optical attenuators: n-1 is less than or equal to M, wherein each optical attenuator only processes one path of optical signal, and M is a positive integer.
3. The DAC of claim 1 wherein the attenuation ratio of each of the plurality of optical attenuators is different from each other, and the attenuation ratio between the plurality of attenuators is 2-1Wherein the minimum attenuation ratio of the optical attenuator is 1/2.
4. The digital-to-analog converter according to claim 2, characterized in that said photoelectric converter comprises M +1 outputs; the M output ends of the photoelectric converter are connected with the M optical attenuators in the optical attenuator group one by one, wherein the M output ends of the photoelectric converter are respectively the output ends from the second high bit data to the lowest bit data in the digital signal.
5. The DAC as claimed in claim 4 wherein the second higher bit data to lowest bit data output of the optical-to-electrical converter is connected in series with the optical attenuator with the largest attenuation ratio to the smallest attenuation ratio.
6. The DAC according to claim 4, wherein an output terminal of the optical-to-electrical converter other than the M output terminals is connected to the adder, and the output terminal connected to the adder is used for outputting one of the N optical signals other than the N-1 optical signals to the adder.
7. The DAC according to claim 6 wherein said output of said photoelectric converter connected to said adder is the output of the highest bit data of the digital signal.
8. The DAC of claim 6 wherein M outputs of the photoelectric converter and M optical attenuators of the optical attenuator group, outputs of the photoelectric converter other than the M outputs and the adder, and the M optical attenuators and the adder are connected by silicon waveguides.
9. A signal processing system, comprising: an electrical chip, an optical digital-to-analog converter according to any of claims 1-8 and a photonic chip; the electrical chip is used for sending a digital signal carrying information to the optical digital-to-analog converter, the optical digital-to-analog converter is used for receiving the digital signal, converting the digital signal into an analog optical signal, and then outputting the analog optical signal to the photonic chip, and the photonic chip is used for performing operation based on the information carried in the analog optical signal.
10. A photonic neural network chip, wherein the photonic neural network chip is provided with a processing device and an optical digital-to-analog converter according to any one of claims 1 to 8, the optical digital-to-analog converter is configured to receive a digital signal transmitted from an electrical chip, convert the digital signal into an analog optical signal, and then transmit the analog optical signal to the processing device, and the processing device is configured to perform an operation based on information carried in the analog optical signal.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111884727A (en) * | 2020-07-15 | 2020-11-03 | 杭州电子科技大学 | High-speed photon digital-to-analog conversion method and system based on digital mapping |
| CN116124482A (en) * | 2023-04-17 | 2023-05-16 | 北京赛德车门制造有限公司 | Sliding plug door switch and auxiliary debugging system and method |
| US11817903B2 (en) | 2020-08-06 | 2023-11-14 | Celestial Ai Inc. | Coherent photonic computing architectures |
| US11835777B2 (en) | 2022-03-18 | 2023-12-05 | Celestial Ai Inc. | Optical multi-die interconnect bridge (OMIB) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6160504A (en) * | 1999-06-30 | 2000-12-12 | Trw Inc. | Repetitive absorptive thresholding optical quantizer |
| CN1652008A (en) * | 2004-02-03 | 2005-08-10 | 朗迅科技公司 | Optical digital-to-analog converter |
| CN102621768A (en) * | 2012-03-22 | 2012-08-01 | 中国科学院半导体研究所 | N-bit optical digital-to-analog converter based on micro ring resonator |
| CN103809346A (en) * | 2014-02-26 | 2014-05-21 | 上海交通大学 | Ultra high-speed optical analog-to-digital conversion device |
| CN104133336A (en) * | 2014-08-12 | 2014-11-05 | 中国科学院半导体研究所 | On-chip integrated optical digital-to-analog converter based on silicon-based nanowire waveguide |
| CN106647102A (en) * | 2016-12-27 | 2017-05-10 | 南京航空航天大学 | Ultra high-speed digital-to-analogue conversion method and device based on optical time domain compression |
-
2020
- 2020-04-23 CN CN202010324501.0A patent/CN111208690B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6160504A (en) * | 1999-06-30 | 2000-12-12 | Trw Inc. | Repetitive absorptive thresholding optical quantizer |
| CN1652008A (en) * | 2004-02-03 | 2005-08-10 | 朗迅科技公司 | Optical digital-to-analog converter |
| CN102621768A (en) * | 2012-03-22 | 2012-08-01 | 中国科学院半导体研究所 | N-bit optical digital-to-analog converter based on micro ring resonator |
| CN103809346A (en) * | 2014-02-26 | 2014-05-21 | 上海交通大学 | Ultra high-speed optical analog-to-digital conversion device |
| CN104133336A (en) * | 2014-08-12 | 2014-11-05 | 中国科学院半导体研究所 | On-chip integrated optical digital-to-analog converter based on silicon-based nanowire waveguide |
| CN106647102A (en) * | 2016-12-27 | 2017-05-10 | 南京航空航天大学 | Ultra high-speed digital-to-analogue conversion method and device based on optical time domain compression |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111884727A (en) * | 2020-07-15 | 2020-11-03 | 杭州电子科技大学 | High-speed photon digital-to-analog conversion method and system based on digital mapping |
| CN111884727B (en) * | 2020-07-15 | 2021-11-16 | 杭州电子科技大学 | High-speed photon digital-to-analog conversion method and system based on digital mapping |
| US11817903B2 (en) | 2020-08-06 | 2023-11-14 | Celestial Ai Inc. | Coherent photonic computing architectures |
| US11835777B2 (en) | 2022-03-18 | 2023-12-05 | Celestial Ai Inc. | Optical multi-die interconnect bridge (OMIB) |
| CN116124482A (en) * | 2023-04-17 | 2023-05-16 | 北京赛德车门制造有限公司 | Sliding plug door switch and auxiliary debugging system and method |
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|---|---|
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