Microwave photon signal generation module and method based on mutually injectable semiconductor lasers

Abstract

The application relates to the technical field of lasers, and provides a microwave photon signal generation module based on mutually injectable semiconductor lasers, which comprises two mutually injectable semiconductor lasers, one of the two semiconductor lasers is a straight modulation laser connected with an RF signal source, the mutual injection light path of the two semiconductor lasers is connected out to a third semiconductor laser through an adjustable optical coupler, the third semiconductor laser is a straight modulation laser connected with an arbitrary waveform generator. The application further provides a microwave photon signal generation method based on mutually injectable semiconductor lasers. The application can generate high-frequency sinusoidal wave signals and high-frequency broadband signals in the optical domain without high-stability light sources, waveguide devices and long optical fibers, reduces the cost of the system, improves the stability of the system, and the core device can be manufactured on a substrate, thereby providing great help for system integration.

Description

Technical Field

[0001] This invention relates to a microwave photonic signal generation module and method based on a mutually injectable semiconductor laser, belonging to the field of laser technology. Background Technology

[0002] In the prior art, to generate high-frequency sinusoidal signals and high-frequency broadband signals simultaneously, it is generally necessary to have a highly stable light source, waveguide devices, and a long circulator circuit. For example, the fast-response magnetic alloy high-frequency system for synchrotrons disclosed in Chinese invention patent application number CN202211709078.1 has high cost, high integration difficulty, and difficulty in ensuring system stability. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides a microwave photonic signal generation module based on a mutually injectable semiconductor laser. This module can generate high-frequency sinusoidal signals and high-frequency broadband signals in the optical domain without requiring highly stable light sources, waveguide devices, or long circulator circuits, thus reducing system costs and improving system stability.

[0004] The present invention is achieved through the following technical solutions.

[0005] The present invention provides a microwave photonic signal generation module based on inter-injectable semiconductor lasers, comprising two inter-injectable semiconductor lasers, one of which is a directly modulated laser connected to an RF signal source, and the inter-injection optical path of the two semiconductor lasers is connected to a third semiconductor laser through a tunable optical coupler. The third semiconductor laser is a directly modulated laser connected to an arbitrary waveform generator.

[0006] All of the semiconductor lasers mentioned are DFB lasers.

[0007] The adjustable optical coupler is a beam splitter with adjustable intensity, which is divided into two beams. The input of the beam splitter is a semiconductor laser optical path connected to an radio frequency signal source.

[0008] A circulator is located between the third semiconductor laser and the tunable optical coupler.

[0009] The present invention also provides a method for generating microwave photonic signals based on inter-injectable semiconductor lasers. The method uses the microwave photonic signal generation module based on inter-injectable semiconductor lasers as described above. By adjusting the frequency and harmonic order of the radio frequency signal source and adjusting the signal state of the arbitrary waveform generator, the method can control the signals emitted by the three semiconductor lasers.

[0010] The signal states of the arbitrary waveform generator include three types: off, same-frequency signal, and modulated signal.

[0011] When the signal state of the arbitrary waveform generator is off, the frequency of the microwave photonic signal is tuned by adjusting the frequency and harmonic order of the radio frequency signal source.

[0012] Two mutually injectable semiconductor lasers are controlled to inject each other to generate a single-cycle oscillation to obtain an optical subcarrier. An arbitrary waveform generator is then controlled to modulate the optical subcarrier to obtain a broadband optical signal.

[0013] Two mutually injectable semiconductor lasers are controlled to inject into each other to generate a single-cycle oscillation signal. This single-cycle oscillation signal is injected into a third semiconductor laser to generate chaos and obtain a chaotic optical carrier. An arbitrary waveform generator is controlled to modulate the chaotic optical carrier to obtain a chaotic signal.

[0014] The beneficial effects of this invention are as follows: it can generate high-frequency sinusoidal signals and high-frequency broadband signals in the optical domain without requiring highly stable light sources, waveguide devices, and long circulator circuits, thus reducing system costs and improving system stability; the core components can be fabricated on a single substrate, greatly facilitating system integration; it can generate multiple frequencies, including tunable single-frequency signals and chaotic signals, and all generated signals can be high-frequency signals above 60 GHz. Attached Figure Description

[0015] Figure 1 This is a connection diagram of at least one embodiment of the present invention. Detailed Implementation

[0016] The technical solution of the present invention is further described below, but the scope of protection is not limited to what is described.

[0017] The first embodiment of the present invention relates to a microwave photonic signal generation module based on a mutually injectable semiconductor laser, such as... Figure 1As shown, it includes two mutually injected semiconductor lasers LD1 and LD2, wherein semiconductor laser LD1 is connected to an RF signal source, and the mutual injection optical path of the two semiconductor lasers is connected to a third semiconductor laser through an adjustable optical coupler (AOC), and the third semiconductor laser LD3 is connected to an arbitrary waveform generator (AWG). Thus, the two semiconductor lasers form a mutual injection structure. When the RF signal source is not working, the microwave seed signal originates from a single-cycle oscillation P1 in semiconductor laser LD1. The other semiconductor laser LD2 performs microwave envelope detection and feedback modulation. Due to the optical injection locking and optical modulation effects in the semiconductor lasers, the P1 signal is enhanced. By coupling the P1 signal with the resonant mode of the mutual injection loop, the stability of the P1 signal can be improved, thereby improving the stability of the P1 signal and finally generating a stable microwave photonic signal without electro-optic modulation and photoelectric conversion. Based on the third semiconductor laser, a chaotic photonic signal is generated through the chaotic state of the semiconductor laser. The vector signal is directly modulated onto the chaotic spectrum through an arbitrary waveform generator, which can realize the modulation of the chaotic optical signal. Moreover, since the microwave photonic signal input from the third semiconductor laser has excellent stability, the chaotic optical signal also has excellent stability.

[0018] Therefore, when RF, DFB-LD3, and AWG are turned off, the first two lasers form a mutual injection structure. By adjusting the power and polarization parameters of the mutual injection loop, a tunable microwave photonic signal output of 5GHz-30GHz can be achieved, and the generated signal can be observed through port 30 of OC1. When only AWG is turned off, the redshift mode and higher harmonics of the first two lasers generate single-cycle oscillations or chaotic states in DFB-LD3, thereby generating a high-frequency microwave photonic signal. By adjusting the frequency and harmonic order of the RF signal, the frequency of the microwave photonic signal can be tunable. The generated microwave signal can be tunable from 30GHz to 150GHz. When all devices are turned on, the signal can be modulated onto a photonic subcarrier or a chaotic carrier to achieve broadband signal generation.

[0019] Therefore, by adopting this scheme, the phase correlation of the two semiconductor lasers is improved through feedback injection of the mutual injection loop. This not only enhances the single-cycle oscillation signal but also greatly improves its stability. As a result, only one mutual injection loop is needed to meet the requirements of stably generating high-frequency sinusoidal signals and high-frequency broadband signals, which greatly reduces costs. This provides a strong foundation for the design and application of on-chip photonic systems and greatly facilitates system integration.

[0020] Furthermore, all semiconductor lasers used are DFB lasers. DFB lasers have advantages such as high single-mode operating stability, narrow linewidth, and fiber compatibility, making them highly effective in this embodiment. In particular, based on the characteristics of DFB lasers, the frequency of the generated microwave signal is determined by the frequency of the P1 signal and the FSR of the mutual injection loops. Therefore, the operating frequency can be easily adjusted by changing the power and polarization of the injected light, as well as the bias current and operating temperature of the DFB-LDs.

[0021] Furthermore, the tunable optical coupler is a 1-to-2 beam splitter, with the optical path of a semiconductor laser connected to an RF signal source serving as the input to the tunable optical coupler. This increases the input light intensity of the third semiconductor laser, ensuring easier modulation of chaotic optical signals. Specifically, when the frequency of one P1 signal is twice that of the other, both P1 signals may be amplified. Normally, when the mutual injection loop is closed, one of the two P1 oscillations will suppress the other, thus dominating the oscillation of the coupled system. However, in the special case where the frequency of one P1 oscillation is twice that of the other, the result is very different.

[0022] The second embodiment of the present invention is largely equivalent to the first embodiment, mainly in that a circulator is present between the third semiconductor laser and the tunable optical coupler. This facilitates the extraction of the optical path and enables convenient debugging and real-time control.

[0023] The third embodiment of the present invention relates to a method for generating microwave photonic signals based on inter-injectable semiconductor lasers. The method uses the microwave photonic signal generation module based on inter-injectable semiconductor lasers described in the above embodiment to control the signals emitted by three semiconductor lasers by adjusting the frequency and harmonic order of the radio frequency signal source and adjusting the signal state of the arbitrary waveform generator.

[0024] Furthermore, the signal states of an arbitrary waveform generator include three types: off, same-frequency signal, and modulated signal.

[0025] Specifically:

[0026] When the signal state of the arbitrary waveform generator is off, the frequency of the microwave photonic signal is tuned by adjusting the frequency and harmonic order of the radio frequency signal source.

[0027] When the signal state of the arbitrary waveform generator is a signal of the same frequency, the arbitrary waveform generator sends a single-cycle oscillation signal to obtain a wideband signal.

[0028] When the signal state of the arbitrary waveform generator is a modulation signal, the arbitrary waveform generator modulates the signals of the three semiconductor lasers to obtain a chaotic signal.

[0029] This demonstrates that the semiconductor laser without a connected radio frequency signal source in one of the two semiconductor lasers exhibits sideband injection lock-in. The P1 generated by the two semiconductor lasers, coupled with sideband injection lock-in, produces microwave photonic signals at higher frequencies (e.g., 100 GHz).

[0030] Therefore, this invention can generate multiple frequencies, including tunable single-frequency signals and chaotic signals, all of which are high-frequency signals above 60 GHz.

[0031] Those skilled in the art will understand that the above embodiments are mainly used to illustrate the principles of the present invention, and in practical applications, various changes can be made in form and detail without departing from the spirit and scope of the present invention.

Claims

1. A method for generating microwave photonic signals based on a mutually injectable semiconductor laser, characterized in that: This method uses a microwave photonic signal generation module based on inter-injectable semiconductor lasers, including two inter-injectable semiconductor lasers. One of the two semiconductor lasers is a directly modulated laser connected to an RF signal source. The inter-injection optical paths of the two semiconductor lasers are connected to a third semiconductor laser via a tunable optical coupler. The third semiconductor laser is a directly modulated laser connected to an arbitrary waveform generator. By adjusting the frequency and harmonic order of the RF signal source and the signal state of the arbitrary waveform generator, the signals emitted by the three semiconductor lasers can be controlled. The signal state of the arbitrary waveform generator includes off, on, and off states. There are three types of signals: frequency signals and modulation signals. When the signal state of the arbitrary waveform generator is off, the frequency of the microwave photonic signal is tuned by adjusting the frequency of the radio frequency signal source. Two mutually injectable semiconductor lasers are controlled to mutually inject each other to generate a single-cycle oscillation to obtain an optical subcarrier. The arbitrary waveform generator is then controlled to modulate the optical subcarrier to obtain a broadband optical signal. Two mutually injectable semiconductor lasers are controlled to mutually inject each other to generate a single-cycle oscillation signal. This single-cycle oscillation signal is injected into a third semiconductor laser to generate chaos to obtain a chaotic optical carrier. The arbitrary waveform generator is then controlled to modulate the chaotic optical carrier to obtain a chaotic signal.

2. The method as described in claim 1, characterized in that: All of the semiconductor lasers mentioned are DFB lasers.

3. The method as described in claim 1, characterized in that: The adjustable optical coupler is a beam splitter with adjustable intensity, which is divided into two beams. The input of the beam splitter is a semiconductor laser optical path connected to an radio frequency signal source.

4. The method as described in claim 1, characterized in that: There is a circulator between the third semiconductor laser and the tunable optical coupler.

Images