CN111313970A

CN111313970A - Arbitrary waveform generating device of integrated chip

Info

Publication number: CN111313970A
Application number: CN202010112991.8A
Authority: CN
Inventors: 石暖暖; 李明; 祝宁华
Original assignee: Institute of Semiconductors of CAS
Current assignee: Institute of Semiconductors of CAS
Priority date: 2020-02-24
Filing date: 2020-02-24
Publication date: 2020-06-19
Anticipated expiration: 2040-02-24
Also published as: CN111313970B

Abstract

The invention provides an arbitrary waveform generating device of an integrated chip, which comprises: the device comprises a spectrum shaping unit and a frequency-time mapping unit connected with the spectrum shaping unit; the spectrum shaping unit is used for performing frequency-domain spectrum shaping on the optical signal to generate a frequency-domain discrete optical signal, inputting the shaped optical signal into the frequency-time mapping unit to map frequency-domain information of the frequency-domain discrete optical signal to a time domain, and generating a time-domain waveform corresponding to the frequency-domain discrete optical signal. The arbitrary waveform generating device provided by the invention belongs to a single integrated chip, and can effectively reduce the volume of the device and reduce the power consumption.

Description

Arbitrary waveform generating device of integrated chip

Technical Field

The invention relates to the technical field of optical signal processing, in particular to an arbitrary waveform generating device of an integrated chip.

Background

The waveform generating device achieves the purpose of pulse shaping by controlling certain tunable parameters of the optical pulse, such as spatial position, amplitude, phase, wavelength and the like on the basis that the pulse width reaches picoseconds or even femtoseconds, thereby obtaining any required waveform. As a tunable waveform generation technology with great potential, the all-optical arbitrary waveform generation not only can generate high-broadband analog microwave signals required in an advanced radar system and an ultra-wideband communication system, but also can generate return-to-zero pulses in a soliton system and an optical time division multiplexing system. In addition, the all-optical arbitrary waveform generator can also generate high-quality coded signals required in an optical code division multiple access system and optical driving signals in an ultra-wideband wireless communication system.

However, the existing waveform generating apparatus still has some disadvantages, such as large volume of the apparatus, high power consumption, and reduced stability of the waveform as the temperature of the chirped dispersive waveguide delay line in the apparatus increases.

Disclosure of Invention

It is an object of the present invention to provide an integrated-chip arbitrary waveform generating apparatus to solve at least one of the above-mentioned technical problems.

To achieve the above object, an embodiment of the present invention provides an arbitrary waveform generating apparatus of an integrated chip, the apparatus including:

the device comprises a spectrum shaping unit and a frequency-time mapping unit connected with the spectrum shaping unit;

the spectrum shaping unit is used for performing frequency-domain spectrum shaping on the optical signal to generate a frequency-domain discrete optical signal, inputting the shaped optical signal into the frequency-time mapping unit to map frequency-domain information of the frequency-domain discrete optical signal to a time domain, and generating a time-domain waveform corresponding to the frequency-domain discrete optical signal.

According to the technical scheme disclosed by the embodiment of the invention, the arbitrary waveform generating device provided by the invention belongs to an integrated chip, so that the volume of the arbitrary waveform generating device is reduced, and the power consumption is reduced.

Drawings

Fig. 1 is a schematic structural diagram of an arbitrary waveform generating apparatus integrated with a chip according to an embodiment of the present invention.

Description of reference numerals:

1. a mode-locked laser; 2-1, an optical switch; 2-2, an optical switch; 2-3, an optical switch; 2-4, an optical switch; 2-5, an optical switch; 3-1, waveguide delay line; 3-2, waveguide delay line; 3-3, waveguide delay line; 4. an optical isolator; 5. an optical power splitter; 6. a chirped dispersion waveguide delay line; 7. a photodetector.

Detailed Description

The technical solutions disclosed in the present invention will be described in detail with reference to the accompanying drawings and specific embodiments, which are understood to be illustrative only and not limiting to the scope of the invention, and various equivalent modifications of the invention will fall within the scope of the invention defined by the appended claims after reading the present invention.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

It will be understood that when an element is referred to as being "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

With reference to fig. 1, an arbitrary waveform generating apparatus of an integrated chip according to an embodiment of the present invention includes:

In some embodiments, the spectral shaping unit and the frequency-time mapping unit are connected by monolithic integration or hybrid integration. The spectrum shaping unit can comprise a mode-locked laser and an optical switch topological network. The mode-locked laser is used for generating a wide-spectrum coherent ultra-narrow optical pulse signal with repetition frequency f; the optical switch topology network is used for performing spectrum shaping on the optical pulse signal generated by the mode-locked laser and outputting a comb-shaped optical signal with any spectrum shape.

Specifically, the optical switch topology network may include a plurality of optical switches and waveguide delay lines, and the plurality of optical switches and the waveguide delay lines are connected in series. Such as optical switches 2-1 to 2-5 in fig. 1; waveguide delay lines 3-1 to 3-3. The optical switch can be used for carrying out channel selection on input optical pulses, and when the optical switch is driven at a low level, the optical pulses are allowed to pass through the optical switch; when driven high, the light pulses are allowed to cross through the optical switch. The waveguide delay line can be used for delaying the input optical pulse, and when the optical pulse directly passes through the optical switch, the optical pulse is delayed; the light pulses are not delayed when they cross through them.

In a specific embodiment, the pulse repetition frequency of the mode-locked laser may be 200MHz, and the pulse width may be 100 femtoseconds, but the pulse repetition frequency and the pulse width may also be appropriately changed within a certain range, and the invention is not limited thereto. Alternatively, the mode-locked laser may be an active laser or a passive mode-locked laser.

In one particular embodiment, the waveguide delay line may be cascaded with the optical switches of the optical switch in sequence with an equal differential delay amount.

In a specific embodiment, the optical switch may be a silicon dioxide, silicon or indium phosphorus based optical switch, and the optical pulse channel switching may be performed by selecting a matching optical switch according to a difference in switching speed. The waveguide delay line may be an optical waveguide of various materials, and the present invention is not limited thereto.

In some embodiments, the frequency-time mapping unit may include an optical isolator 4, an optical power splitter 5, a chirped dispersive waveguide delay line 6, and a photodetector 7. The optical isolator 4 can perform optical pulse direction selective channel to enable optical signals in a specified direction to pass through; the optical power splitter 5 may be configured to perform power distribution on the output spectrally shaped optical pulse to form a three-port transmission system; the chirped dispersion waveguide delay line 6 can be used for performing frequency domain dispersion stretching on an optical signal to map the optical signal from a frequency domain to a time domain, the chirped dispersion waveguide delay line 6 can be made of a silicon dioxide, silicon or indium phosphorus based optical waveguide material, and the optical waveguide material is selected according to the requirement of delay amount; the photodetector 7 may be used to perform photoelectric conversion on the optical signal mapped to the time domain, thereby obtaining an electrical signal of an arbitrary waveform.

In one particular embodiment, the optical isolator 4 may allow a counter-clockwise spectrally shaped optical pulse to pass through and transmit, and cut off the optical pulse returning clockwise from the chirped dispersive waveguide delay line 6.

In one particular embodiment, the bandwidth of the photodetector 7 may be 50 GHz.

In some embodiments, the chirped dispersion waveguide delay line 6 may be in contact with an external semiconductor refrigerator to control the temperature of the chirped dispersion waveguide delay line 6, so as to avoid the problem that the temperature of the chirped dispersion waveguide delay line 6 is too high, which leads to the decrease of waveform stability.

The above embodiments in the present specification are all described in a progressive manner, and the same and similar parts among the embodiments may be referred to each other, and each embodiment is described with emphasis on being different from other embodiments.

The above description is only a few embodiments of the present invention, and although the embodiments of the present invention are described above, the above description is only for the convenience of understanding the technical scheme of the present invention, and is not intended to limit the present invention. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. An integrated chip arbitrary waveform generation apparatus, comprising:

2. The apparatus of claim 1, wherein the spectral shaping unit comprises:

the mode-locked laser is used for generating a wide-spectrum coherent ultra-narrow optical pulse signal with specified repetition frequency;

and the optical switch topology network is used for performing spectrum shaping on the optical pulse signal generated by the mode-locked laser and outputting a comb-shaped optical signal.

3. The apparatus of claim 2, wherein the optical switching topology network comprises:

the optical switch comprises a plurality of optical switches and a waveguide delay line, wherein the optical switches and the waveguide delay line are connected in series.

4. The apparatus of claim 2, wherein the mode-locked laser is an active laser or a passive mode-locked laser.

5. The apparatus of claim 3, wherein the topological network of optical switches is an integrated chip of silicon dioxide, silicon or indium phosphide.

6. The apparatus of claim 1, wherein the frequency-to-time mapping unit comprises:

an optical isolator for passing an optical signal in a specified direction;

the optical power divider is used for performing power distribution on the optical signal;

the chirp dispersion waveguide delay line is used for carrying out frequency domain dispersion stretching on the optical signal so as to map frequency domain information of the optical signal to a time domain;

and the photoelectric detector is used for performing photoelectric conversion on the optical signal mapped to the time domain.

7. The apparatus of claim 6, wherein the chirped, dispersive waveguide delay line is a silica, silicon or indium phosphide integrated chip.

8. The apparatus of claim 6, wherein the chirped, dispersive waveguide delay line is in contact with an external semiconductor refrigerator to control the temperature of the chirped, dispersive waveguide delay line.

9. The apparatus of claim 1, wherein the spectral shaping unit and the frequency-time mapping unit are connected by monolithic integration or hybrid integration.