Communication systems and methods based on integrated photonics for fiber optic and wireless communication

Abstract

This invention provides a communication system and method based on integrated photonics for optical fiber communication and wireless communication. The system includes: a baseband transmitter, a first optical fiber link, a radio frequency (RF) repeater, a second optical fiber link, and a baseband receiver. The baseband transmitter converts the original electrical signal into an optical baseband signal. The baseband transmitter and the RF repeater are connected via the first optical fiber link. The RF repeater converts the received optical baseband signal into a target electrical signal in the target terahertz frequency band. The target electrical signal is transmitted through a wireless transmission module, and a wireless receiving module receives the target electrical signal. A second integrated electro-optic modulator converts the target electrical signal into an optical intermediate frequency (IF) signal. The RF repeater and the baseband receiver are connected via the second optical fiber link. The baseband receiver converts the optical IF signal into an output electrical signal. This invention's system can balance the high speed of optical fiber communication and the flexibility of wireless communication, achieving ultra-high-speed, low-latency communication transmission across the entire link.

Description

Technical Field

[0001] This invention relates to the field of communication technology, and in particular to a communication system and method based on integrated photonics for optical fiber communication and wireless communication. Background Technology

[0002] With the rapid development of diverse applications such as the Internet of Things, ultra-high-definition video, and holographic communication, higher demands are being placed on data transmission capacity and latency in different scenarios. In the field of wired communication, fiber optic communication has become the main connection method in metropolitan area networks or data centers due to its larger bandwidth and ability to support longer transmission distances. However, its transmission relies on fiber optics as the propagation medium, which limits its flexible deployment. Furthermore, the laying and maintenance of fiber optic infrastructure in harsh environments or remote areas is one of the urgent problems to be solved in the field of fiber optic communication.

[0003] Wireless communication, due to its lack of fixed physical channels, offers superior characteristics such as flexible transmission and rapid topology reconfiguration, making it the mainstream technology for mobile access networks. However, limited by carrier frequency, the total allocated bandwidth of current wireless communication is still confined to within 10 GHz, which restricts the total channel throughput and cannot further meet the ever-increasing demand for communication capacity.

[0004] In summary, existing technologies cannot simultaneously achieve the high speed of fiber optic communication and the flexibility of wireless communication, as well as the non-blocking conversion between them. A completely new solution is urgently needed to achieve ultra-high-speed, low-latency communication transmission across the entire link. Summary of the Invention

[0005] This invention provides a communication system based on integrated photonics for optical fiber communication and wireless communication, which solves the shortcomings of existing technologies such as the inability of optical fiber communication to achieve flexible deployment and the limitation of wireless communication to carrier frequency. It combines the high speed of optical fiber communication with the flexibility of wireless communication to achieve ultra-high speed and low latency communication transmission across the entire link.

[0006] This invention also proposes a communication method based on integrated photonics for optical fiber communication and wireless communication.

[0007] This invention discloses a communication system based on integrated photonics for fiber optic and wireless communication, comprising: The baseband transmitter includes a first integrated electro-optic modulator, which is used to convert the original electrical signal of the baseband transmitter into an optical baseband signal. The radio frequency (RF) relay terminal is connected to the baseband transmitter terminal via a first optical fiber link. The optical baseband signal is transmitted to the RF relay terminal via the first optical fiber link. The RF relay terminal includes a first integrated photodetector, a wireless transmitting module, a wireless receiving module, and a second integrated electro-optic modulator. The first integrated photodetector is used to convert the received optical baseband signal into a target electrical signal in the target terahertz frequency band. The target electrical signal is transmitted through the wireless transmitting module, and the wireless receiving module is used to receive the target electrical signal. The second integrated electro-optic modulator is used to convert the target electrical signal into an optical intermediate frequency (IF) signal. The baseband receiver is connected to the radio frequency relay terminal via a second optical fiber link. The optical intermediate frequency signal is transmitted to the baseband receiver via the second optical fiber link. The baseband receiver includes a second integrated photodetector, which is used to convert the optical intermediate frequency signal into an output electrical signal.

[0008] It is understandable that the first integrated electro-optic modulator, the first integrated photodetector, the second integrated electro-optic modulator, and the second integrated photodetector are components of terahertz wireless communication technology with integrated photons.

[0009] According to the present invention, a communication system based on integrated photonics for optical fiber communication and wireless communication is provided. The baseband transmitter includes a signal source, a first integrated electro-optic modulator, and a first laser. The first laser is used to generate a transmitter optical carrier, and the signal source is used to generate a raw electrical signal. The optical input terminal of the first integrated electro-optic modulator is connected to the first laser, and the electrical input terminal is connected to the signal source. The first integrated electro-optic modulator is used to convert the raw electrical signal and the transmitter optical carrier into an optical baseband signal.

[0010] According to the present invention, a communication system based on integrated photonics for fiber optic and wireless communication includes a radio frequency relay terminal comprising a second laser, a first integrated photodetector, a wireless transmitting module, a wireless receiving module, a third laser, and a second integrated electro-optic modulator. The second laser generates a local oscillator signal, and a preset frequency difference exists between the local oscillator signal and the optical baseband signal, the preset frequency difference corresponding to the carrier frequency of a target terahertz frequency. The first integrated photodetector combines the local oscillator signal with the optical baseband signal amplified by the first fiber optic link to generate a target electrical signal in the target terahertz frequency band. The wireless transmitting module is connected to the first integrated photodetector and transmits the target electrical signal wirelessly. The wireless receiving module receives the target electrical signal. The third laser generates a receiving optical carrier. The optical input terminal of the second integrated electro-optic modulator is connected to the third laser, and the electrical input terminal is connected to the wireless receiving module. The second integrated electro-optic modulator converts the receiving optical carrier and the target electrical signal into an optical intermediate frequency signal.

[0011] According to the present invention, a communication system based on integrated photonics for optical fiber communication and wireless communication is provided. The baseband receiver includes a second integrated photodetector and a receiving processing unit. The second integrated photodetector is used to perform photoelectric conversion on the optical intermediate frequency signal amplified by the second optical fiber link to generate an output electrical signal. The receiving processing unit is connected to the second integrated photodetector.

[0012] According to the present invention, a communication system based on integrated photonics for optical fiber communication and wireless communication is provided, wherein the first optical fiber link includes a first optical fiber and a first optical fiber amplifier, and the first optical fiber amplifier is disposed on one end of the first optical fiber near the radio frequency relay end; And / or, The second optical fiber link includes a second optical fiber and a second optical fiber amplifier, with the second optical fiber amplifier located on one end of the second optical fiber near the baseband receiver.

[0013] According to the present invention, a communication system based on integrated photonics for optical fiber communication and wireless communication is provided, wherein the first integrated electro-optic modulator and the second integrated electro-optic modulator are thin-film lithium niobate electro-optic modulators.

[0014] According to the present invention, a communication system based on integrated photonics for optical fiber communication and wireless communication includes a thin-film lithium niobate electro-optic modulator comprising: The system consists of an input end-face coupler, an input low-loss optical waveguide, an input multimode interferometer, a modulation arm optical waveguide, an output multimode interferometer, an output low-loss optical waveguide, and an output end-face coupler, all connected sequentially. The modulation arm optical waveguide is equipped with a coplanar waveguide traveling-wave electrode, which includes an electro-optic interaction region. Parallel to the surface of the electro-optic modulator substrate, the signal lines of the electro-optic interaction region facing the surface of the corresponding modulation arm optical waveguide are provided with multiple patterned slow-wave electrode structures.

[0015] According to the present invention, a communication system based on integrated photonics for optical fiber communication and wireless communication is provided, wherein the first integrated photodetector and the second integrated photodetector are single-row carrier photodetectors.

[0016] According to the present invention, a communication system based on integrated photonics for optical fiber communication and wireless communication includes a single-row carrier photodetector comprising a substrate structure, an epitaxial structure, and a metal output structure. The substrate structure is connected to the epitaxial structure. The epitaxial structure comprises an InGaAsP waveguide layer, an InP drift layer, and an InGaAs absorption layer. The InGaAsP waveguide layer is connected to the substrate structure, the InP drift layer is connected to the InGaAsP waveguide layer, and the InGaAs absorption layer is connected to the InP drift layer. The metal output structure comprises a first metal element, a second metal element, and a BCB buffer. A first end of the first metal element is connected to the substrate structure, a first end of the second metal element is connected to the InGaAs absorption layer, and the BCB buffer is disposed below the second ends of the first metal element and the second metal element.

[0017] This invention provides a communication method for optical fiber communication and wireless communication based on integrated photonics, comprising the following steps.

[0018] At the baseband transmitter, the original electrical signal is converted into an optical baseband signal by the first integrated electro-optic modulator; The optical baseband signal is transmitted to the radio frequency relay end through the first optical fiber link; At the radio frequency relay end, the optical baseband signal is converted into a target electrical signal in the target terahertz frequency band by the first integrated photodetector, and the target electrical signal is wirelessly transmitted through the wireless transmission module; The target electrical signal is received by a wireless receiving module, and the target electrical signal is converted into an optical intermediate frequency signal by a second integrated electro-optic modulator. The optical intermediate frequency signal is transmitted to the baseband receiver via a second optical fiber link; At the baseband receiver, the optical intermediate frequency signal is converted into an output electrical signal by a second integrated photodetector.

[0019] This invention provides a communication system based on integrated photonics for fiber optic and wireless communication. A baseband transmitter converts a raw electrical signal into an optical baseband signal, which can be transmitted at high speed to a radio frequency (RF) repeater via a first fiber optic link. A first integrated photodetector at the RF repeater converts the received optical baseband signal into a target electrical signal in the target terahertz frequency band. The RF repeater's wireless transmitter module transmits the target electrical signal into external space, where it is received by a wireless receiver module. A second integrated electro-optic modulator at the RF repeater then converts the target electrical signal into an optical intermediate frequency (IF) signal. This IF signal is transmitted to the baseband receiver via the second fiber optic link. The second integrated photodetector at the baseband receiver converts the IF signal into an output electrical signal. The efficient and wideband conversion between light and electricity is achieved through the first integrated electro-optic modulator, first integrated photodetector, second integrated electro-optic modulator, and second integrated photodetector. This effectively utilizes the ultra-high bandwidth and low-loss characteristics of the fiber optic link to handle backbone signal transmission and effectively leverages the extremely high bandwidth and flexibility of terahertz wireless communication to achieve flexible access. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of the communication system based on integrated photonics for optical fiber communication and wireless communication provided by the present invention.

[0022] Figure 2 This is one of the structural schematic diagrams of the thin-film lithium niobate electro-optic modulator provided by the present invention.

[0023] Figure 3 This is the second schematic diagram of the thin-film lithium niobate electro-optic modulator provided by the present invention.

[0024] Figure 4 This is a schematic diagram of the structure of the single-row carrier photodetector provided by the present invention.

[0025] Figure 5 This is a flowchart illustrating the communication method for optical fiber communication and wireless communication based on integrated photonics provided by the present invention.

[0026] Figure 6 This is a schematic diagram of the structure of the electronic device provided by the present invention.

[0027] Figure label: 100. Baseband transmitter; 110. First integrated electro-optic modulator; 120. First laser; 130. Signal source; 200, Radio frequency repeater; 210, First integrated photodetector; 220, Second laser; 230, Wireless transmitter module; 240, Wireless receiver module; 250, Third laser; 260, Second integrated electro-optic modulator; 300, Baseband receiver; 310, Second integrated photodetector; 320, Receiver processing unit; 400, First fiber optic link; 410, First fiber optic amplifier; 420, First fiber optic cable; 500, Second fiber optic link; 510, Second fiber optic amplifier; 520, Second fiber optic cable; 1001. Input end-face coupler; 1002. Input low-loss optical waveguide; 1003. Input multimode interferometer; 1004. Modulation arm optical waveguide; 1005. Output multimode interferometer; 1006. Output low-loss optical waveguide; 1007. Output end-face coupler; 1008. Coplanar waveguide traveling wave electrode; 10080. Patterned slow-wave electrode structure; 10081. Electro-optic interaction region; 10082. Input / output region; 10083. Transition region; 2010, Substrate structure; 2020, Epitaxial structure; 2021, InGaAsP waveguide layer; 2022, InP drift layer; 2023, InGaAs absorption layer; 2030, Metal extraction structure; 2031, First metal component; 2032, Second metal component; 2033, BCB buffer component. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0029] The following is combined Figures 1 to 6 The present invention describes a communication system and method for optical fiber communication and wireless communication based on integrated photonics.

[0030] like Figure 1As shown, this invention provides a communication system (hereinafter referred to as the system) based on integrated photonics for optical fiber communication and wireless communication, mainly comprising a baseband transmitter 100, a radio frequency repeater 200, and a baseband receiver 300. The system combines high-speed optical fiber links with high-bandwidth terahertz wireless communication, utilizing integrated photonic devices to achieve efficient, low-loss signal conversion and transmission. It is suitable for future 6G mobile communication fronthaul, data center interconnection, satellite ground stations, and other application scenarios requiring high capacity, long distance, and flexible access convergence.

[0031] The communication system based on integrated photonics for fiber optic and wireless communication of the present invention includes: The baseband transmitter 100 includes a first integrated electro-optic modulator 110, which is used to convert the original electrical signal of the baseband transmitter 100 into an optical baseband signal. The radio frequency (RF) relay terminal 200 is connected to the baseband transmitter terminal 100 via a first optical fiber link 400. The optical baseband signal is transmitted to the RF relay terminal 200 via the first optical fiber link 400. The RF relay terminal 200 includes a first integrated photodetector 210, a wireless transmitter module 230, a wireless receiver module 240, and a second integrated electro-optic modulator 260. The first integrated photodetector 210 is used to convert the received optical baseband signal into a target electrical signal in the target terahertz frequency band. The target electrical signal is transmitted through the wireless transmitter module 230, and the wireless receiver module 240 is used to receive the target electrical signal. The second integrated electro-optic modulator 260 is used to convert the target electrical signal into an optical intermediate frequency (IF) signal. The baseband receiver 300 is connected to the radio frequency relay 200 via a second optical fiber link 500. The optical intermediate frequency signal is transmitted to the baseband receiver 300 via the second optical fiber link 500. The baseband receiver 300 includes a second integrated photodetector 310, which is used to convert the optical intermediate frequency signal into an output electrical signal.

[0032] Understandably, the baseband transmitter 100 can be deployed in a central computer room or on the data source side, and the first integrated electro-optic modulator 110 can be fabricated using a lithium niobate thin-film platform. The original electrical signal undergoes electro-optic conversion through the first integrated electro-optic modulator 110, outputting an optical baseband signal carrying baseband electrical signal information.

[0033] The first fiber optic link 400 can range in length from hundreds of meters to tens of kilometers, and is responsible for transmitting optical baseband signals at low loss and high speed to the remote radio frequency repeater 200.

[0034] The radio frequency (RF) repeater 200 integrates photoelectric conversion, wireless transceiver, and electro-optic remodulation functions. The RF repeater 200 receives the optical baseband signal from the first optical fiber link 400, which is then converted into a target electrical signal by the first integrated photodetector 210 and subsequently sent to the wireless transmission module 230. After transmitting a distance in space, the electrical signal is received by the wireless receiving module 240 at the same node. This electrical signal then undergoes a second electro-optic conversion by the second integrated electro-optic modulator 260 to generate an optical intermediate frequency (IF) signal.

[0035] The second fiber optic link 500 transmits the optical intermediate frequency signal back to the baseband receiver 300. Similarly, the length of the second fiber optic link 500 can range from hundreds of meters to tens of kilometers.

[0036] The baseband receiver 300 is deployed in a data center or on the user side, and the second integrated photodetector 310 converts the optical intermediate frequency signal into an output electrical signal for subsequent digital signal processing or direct use.

[0037] The integrated photonics-based converged communication system provided by this invention, compared to traditional systems built with discrete devices or independently deployed wired and wireless systems, boasts ultra-high bandwidth and ultra-large capacity. The system fully utilizes the enormous physical bandwidth potential of fiber optic communication and terahertz wireless communication. The inherent broadband characteristics (up to hundreds of GHz) of integrated photonic devices ensure that signal conversion between the optical and electrical domains does not become a bottleneck, achieving end-to-end ultra-high-speed data transmission. Furthermore, it enhances flexibility and scalability by perfectly combining stable long-distance fiber optic transmission with flexible short-distance wireless access through an architecture of "fiber optic transmission + terahertz wireless access." The RF repeater 200 can be flexibly deployed in "last mile" areas where direct fiber optic cabling is difficult (such as indoors, street corners, and temporary meeting venues). Multiple RF repeaters 200 can be connected through the same trunk fiber, facilitating on-demand allocation of network capacity and flexible expansion of coverage.

[0038] The working process of the system of this invention is a complete closed loop of signal flow from "electricity-optical-electricity-wireless-electricity-optical-electricity". It achieves efficient and broadband conversion between light and electricity through the first integrated electro-optic modulator 110, the first integrated photodetector 210, the second integrated electro-optic modulator 260, and the second integrated photodetector 310. This effectively utilizes the ultra-high bandwidth and low loss characteristics of the optical fiber link to carry out backbone signal transmission, and effectively utilizes the extremely high bandwidth and flexibility of terahertz wireless communication to achieve flexible access.

[0039] It is understood that the first integrated electro-optic modulator 110, the first integrated photodetector 210, the second integrated electro-optic modulator 260, and the second integrated photodetector 310 are components of terahertz wireless communication technology with integrated photons.

[0040] According to the present invention, a communication system based on integrated photonics for optical fiber communication and wireless communication is provided. The baseband transmitter 100 includes a signal source 130, a first integrated electro-optic modulator 110, and a first laser 120. The first laser 120 is used to generate a transmitter optical carrier, and the signal source 130 is used to generate a raw electrical signal. The optical input terminal of the first integrated electro-optic modulator 110 is connected to the first laser 120, and the electrical input terminal is connected to the signal source 130. The first integrated electro-optic modulator 110 is used to convert the raw electrical signal and the transmitter optical carrier into an optical baseband signal.

[0041] Understandably, signal source 130 generates the original electrical signal to be transmitted. This original electrical signal can be a high-speed digital baseband signal from the digital signal processing unit or an analog intermediate frequency signal. First laser 120 generates a transmitting optical carrier. The optical input of first integrated electro-optic modulator 110 is connected to first laser 120 via an on-chip waveguide or optical fiber to receive continuous transmitting optical carriers; its electrical input is connected to signal source 130 via a high-frequency probe or wire to receive the original electrical signal. First integrated electro-optic modulator 110, based on silicon-based or thin-film lithium niobate platforms, utilizes the electro-optic effect to convert voltage changes in the electrical signal into intensity or phase changes in the optical carrier, thereby outputting an optical baseband signal.

[0042] According to one embodiment of the present invention, the radio frequency relay terminal 200 includes a second laser 220, a first integrated photodetector 210, a wireless transmitting module 230, a wireless receiving module 240, a third laser 250, and a second integrated electro-optic modulator 260. The second laser 220 is used to generate a local oscillator signal, and the local oscillator signal and the optical baseband signal have a preset frequency difference, the preset frequency difference corresponding to the carrier frequency of the target terahertz. The first integrated photodetector 210 is used to connect the local oscillator signal with the optical baseband signal amplified by the first optical fiber link 400. The signals are combined to generate a target electrical signal in the target terahertz frequency band; the wireless transmitting module 230 is connected to the first integrated photodetector 210 and is used to wirelessly transmit the target electrical signal; the wireless receiving module 240 is used to receive the target electrical signal; the third laser 250 is used to generate a receiving optical carrier; the optical input terminal of the second integrated electro-optic modulator 260 is connected to the third laser 250, and the electrical input terminal is connected to the wireless receiving module 240; the second integrated electro-optic modulator 260 is used to convert the receiving optical carrier and the target electrical signal into an optical intermediate frequency signal.

[0043] Understandably, the second laser 220 generates a highly stable local oscillation source signal, and its optical carrier frequency maintains a fixed preset frequency difference with the baseband transmitter 100. The preset frequency difference directly corresponds to the target terahertz carrier frequency. For example, if a 300 GHz wireless signal needs to be generated, the preset frequency difference is set to 300 GHz.

[0044] The optical input end of the first integrated photodetector 210 combines the optical baseband signal from the first optical fiber link 400 with the local oscillator signal from the second laser 220. When the two beams interfere within the detector, a target electrical signal in the target terahertz frequency band is generated, the frequency of which is precisely determined by the optical frequency difference and has low phase noise.

[0045] The wireless transmitting module 230 is connected to the output of the first integrated photodetector 210 to propagate the target electrical signal in the terahertz frequency band into space, and the wireless receiving module 240 receives the target electrical signal that has been propagated into space and returned.

[0046] The third laser 250 generates the optical carrier at the receiver for subsequent electro-optical conversion.

[0047] The second integrated electro-optic modulator 260 has its optical input connected to the third laser 250 and its electrical input connected to the output of the wireless receiver module 240. It modulates the electrical signal recovered by the wireless receiver module 240 onto the optical carrier at the receiver end, generating an optical intermediate frequency signal, which is prepared for transmission to the baseband receiver end 300 via the second optical fiber link 500.

[0048] Understandably, generating terahertz electrical signals directly from the optical frequency difference using the optical heterodyne method avoids the inefficiencies, phase noise accumulation, and bandwidth limitations of traditional electronic frequency doubling chains. The frequency of the generated terahertz signal is precisely determined by the optical frequency difference between the two lasers, offering high flexibility.

[0049] According to one embodiment of the present invention, the baseband receiver 300 includes a second integrated photodetector 310 and a receiving processing unit 320. The second integrated photodetector 310 is used to perform photoelectric conversion on the optical intermediate frequency signal amplified by the second optical fiber link 500 to generate an output electrical signal. The receiving processing unit 320 is connected to the second integrated photodetector 310.

[0050] The second integrated photodetector 310 receives the optical intermediate frequency signal transmitted back through the second optical fiber link 500, performs photoelectric conversion, and generates the initial output electrical signal.

[0051] According to one embodiment of the present invention, the first optical fiber link 400 includes a first optical fiber 420 and a first optical fiber amplifier 410, wherein the first optical fiber amplifier 410 is disposed on one end of the first optical fiber near the radio frequency relay end 200.

[0052] According to one embodiment of the present invention, the second optical fiber link 500 includes a second optical fiber 520 and a second optical fiber amplifier 510, wherein the second optical fiber amplifier 510 is disposed on the second optical fiber near the baseband receiver 300.

[0053] According to one embodiment of the present invention, referring to Figure 2 and Figure 3 The first integrated electro-optic modulator 110 and the second integrated electro-optic modulator 260 are thin-film lithium niobate electro-optic modulators.

[0054] According to one embodiment of the present invention, the thin-film lithium niobate electro-optic modulator includes: The input end-face coupler 1001, input low-loss optical waveguide 1002, input multimode interferometer 1003, modulation arm optical waveguide 1004, output multimode interferometer 1005, output low-loss optical waveguide 1006, and output end-face coupler 1007 are sequentially optically connected. The modulation arm optical waveguide 1004 is correspondingly provided with a coplanar waveguide traveling wave electrode 1008, which includes an electro-optic interaction region 10081. Parallel to the surface of the electro-optic modulator substrate, the signal lines of the electro-optic interaction region 10081 facing the surface of the corresponding modulation arm optical waveguide 1004 are provided with multiple patterned slow-wave electrode structures 10080.

[0055] Specifically, sequential optical connection refers to the direct connection between optical elements through optical propagation components, enabling optical signals to be transmitted from one element to the next in a specified order. Input end-face coupler 1001 and output end-face coupler 1007 are located at the chip's input and output ends, respectively, and are components used to couple optical signals between external optical fibers and internal waveguides within the chip. Input low-loss optical waveguide 1002 and output low-loss optical waveguide 1006 are waveguide structures used to transmit optical signals with low loss within the chip. Input multimode interferometer 1003 and output multimode interferometer 1005 are optical elements that utilize the principle of multimode interference to achieve optical signal beam splitting and combining. Modulation arm optical waveguide 1004 is located between the multimode interferometers, and its optical properties can be modulated by an external electric field; it is used to carry phase modulation. Coplanar waveguide traveling wave electrode 1008 is a microwave transmission line structure in which the central signal line and the preset potential signal lines on both sides, such as ground lines, are located on the same plane; it is used to transmit high-frequency modulated electrical signals. The electro-optic interaction region 10081 is the section in the coplanar waveguide traveling wave electrode 1008 where the generated electric field effectively interacts with the optical field in the modulation arm optical waveguide 1004, thereby achieving electro-optic modulation. The patterned slow-wave electrode structure 10080 is an electrode configuration with specific repeating or non-repeating patterns fabricated on the transmission line side of the coplanar waveguide traveling wave electrode 1008, which can reduce the microwave phase velocity.

[0056] An optical signal enters the input end-face coupler 1001 from an external optical fiber and is efficiently coupled into the electro-optic modulator chip. The coupled optical signal is transmitted to the input multimode interferometer 1003 via the input low-loss optical waveguide 1002, where it is split into, for example, two optical signals of equal intensity, and then enter the two modulation arm optical waveguides 1004 respectively. Simultaneously, a high-frequency electrical signal, i.e., microwaves, is applied to the traveling wave electrodes 1008 of the coplanar waveguide and propagates in the form of a traveling wave. In the electro-optic region 10081, multiple patterned slow-wave electrode structures 10080 can alter the propagation characteristics of the microwaves. When microwaves pass through, these patterned slow-wave electrode structures 10080 generate local electromagnetic field disturbances, effectively increasing the distributed capacitance and / or distributed inductance of the microwave transmission line, thereby reducing the phase velocity of the microwaves, i.e., increasing the effective refractive index of the microwaves. This allows the microwaves to maintain approximately synchronization with the light waves propagating in the modulation arm optical waveguides 1004. During this process, the microwave signal changes the refractive index of the modulation arm waveguide 1004 through the electro-optic effect, thereby modulating the phase of the two optical signals. The two modulated optical signals interfere in the output multimode interferometer 1005 and are combined into a single beam of modulated optical signal, which is finally output to the electro-optic modulator chip via the output low-loss waveguide 1006 and the output end coupler 1007.

[0057] Therefore, this embodiment of the invention achieves effective control of microwave propagation speed by setting multiple patterned slow-wave electrode structures 10080 on the signal line of the electro-optic region 10081, matching it with the speed of light. This solves the problem of limited modulation bandwidth caused by speed mismatch in traditional traveling-wave electrodes, realizing ultra-wideband electro-optic modulation. Furthermore, by constructing the entire modulator based on a thin-film lithium niobate material platform, sufficient refractive index change can be generated with only a very low driving voltage, achieving low-power modulation. Combined with a multimode interferometer and modulation arm waveguide 1004, the chip integration density is greatly improved. Simultaneously, the design of the end-face coupler structure improves optoelectronic coupling efficiency.

[0058] Specifically, addressing the technical problem of bandwidth limitation, this embodiment of the invention provides a coplanar waveguide traveling-wave electrode 1008, combined with multiple patterned slow-wave electrode structures 10080 on the signal line of the electro-optic interaction region 10081. The traveling-wave electrode itself is designed to solve high-speed modulation, allowing microwave signals to propagate along with light waves in a traveling-wave form, overcoming the bandwidth limitation of lumped electrodes. In thin-film lithium niobate modulators, the speed of light is still faster than the speed of microwaves on conventional electrodes. This embodiment of the invention increases the distributed capacitance of the microwave transmission line by creating specific patterns on the signal line, thereby reducing the phase velocity of the microwave, i.e., increasing the effective refractive index of the microwave. This allows the speed of the microwave to be increased to a level matching the speed of the light wave. Speed ​​matching ensures that the microwave and light waves remain synchronized throughout the entire interaction region, thus pushing the electro-optic bandwidth to its theoretical limit and fundamentally solving the bandwidth limitation problem caused by speed mismatch.

[0059] In some embodiments, referring to Figures 1-2, the coplanar waveguide traveling wave electrode 1008 further includes an input / output region and a transition region connecting the input / output region and the electro-optic region 10081. The transition region includes an impedance-gradient transmission line for continuously transitioning the characteristic impedance between the input / output region and the electro-optic region 10081.

[0060] Specifically, the input / output region is the area where the coplanar waveguide traveling wave electrode 1008 connects to the external circuit. It can be designed with a standard impedance for impedance matching with the external signal source 130. The transition region is the segment connecting the input / output region and the electro-optic interaction region 10081. An impedance-gradient transmission line is a transmission line whose characteristic impedance changes continuously or quasi-continuously along its length.

[0061] Because the electro-optic interaction region 10081 employs a patterned slow-wave electrode structure 10080 to optimize electro-optic interaction, its characteristic impedance differs from that of the standard impedance input and output regions. Direct connection would cause microwave signal reflection at the interface due to impedance abrupt changes. The transition region is designed as an impedance-gradient transmission line, ensuring its characteristic impedance smoothly and continuously changes from the impedance value of the input / output regions along the signal transmission direction to the impedance value of the electro-optic interaction region 10081. This gradual impedance profile avoids drastic impedance mismatch, allowing microwave signals to be transmitted from the input / output regions to the electro-optic interaction region 10081 with almost no reflection. Therefore, this embodiment of the invention, by setting an impedance-gradient transition region, greatly suppresses microwave reflection, ensuring effective utilization of microwave power and flatness of the frequency response, which is a crucial guarantee for achieving ultra-wideband performance.

[0062] This invention relates to an integrated electro-optic modulator built on a thin-film lithium niobate material platform. Thin-film lithium niobate possesses a very large linear electro-optic coefficient, much stronger than the free carrier effect of silicon. Its modulation mechanism directly changes the refractive index through an electric field, without the need for carrier injection or depletion. Therefore, only a very low driving voltage is required to generate sufficient refractive index change, achieving low-power modulation.

[0063] In this embodiment of the invention, end-face couplers are provided at the optical path inlet and outlet. The refractive index difference between the thin-film lithium niobate and the silicon dioxide cladding is moderate. Although the mode field size of its single-mode waveguide is still smaller than that of optical fiber, the degree of mismatch is much smaller than that of silicon waveguide. By optimizing the end-face coupler structure, the conversion from the large mode field of optical fiber to the small mode field of electro-optic modulator chip can be efficiently completed, thereby improving the optoelectronic coupling efficiency.

[0064] In one embodiment, to achieve ultra-wideband, high-linearity electro-optic modulation from DC to terahertz frequency bands, the traveling wave electrodes of the first integrated electro-optic modulator 110 and the second integrated electro-optic modulator 260 of the present invention both adopt an optimized patterned slow-wave electrode structure 10080.

[0065] The patterned slow-wave electrode structure 10080 is preferably a T-shaped structure. By precisely optimizing the geometric parameters of the patterned slow-wave electrode structure 10080 (including the trunk length, trunk width, and top width), the propagation characteristics of the microwave signal can be simultaneously controlled. The T-shaped structure effectively reduces the effective refractive index of the microwave signal by increasing the coupling capacitance between the electrode and the ground plane, achieving speed matching between the effective refractive index of the microwave signal and the effective refractive index of the optical signal in the DC to terahertz frequency band, and reducing microwave transmission loss.

[0066] This invention effectively reduces the refractive index of microwaves, making it consistent with the effective refractive index of optical signals in the range exceeding 200 GHz. The mismatch error between the two refractive indices is less than 1%, thereby achieving excellent speed matching performance, avoiding frequency response jitter caused by speed mismatch, and realizing flat electro-optic conversion from DC to terahertz.

[0067] Meanwhile, traditional rectangular electrodes tend to cause abnormal concentration of current density near the edge of the optical waveguide, thereby increasing ohmic loss. The T-shaped structure effectively alleviates this effect by providing a better current distribution path, significantly reducing microwave transmission loss and improving the electro-optic bandwidth of the modulator.

[0068] In one embodiment, the optimized electrode topography parameters of the input end-face coupler 1001, input low-loss optical waveguide 1002, input multimode interferometer 1003, modulation arm optical waveguide 1004, output multimode interferometer 1005, output low-loss optical waveguide 1006, output end-face coupler 1007, and coplanar waveguide traveling wave electrode 1008 enable the characteristic impedance of the electrodes to achieve a high degree of matching with the 50-ohm impedance of a standard microwave RF system over a wide bandwidth exceeding 200 GHz, with an impedance error of less than 1%. This excellent impedance matching significantly suppresses microwave signal reflection at the electrode input, effectively avoiding electro-optic response resonance peaks and ripples caused by reflection, ensuring stable and linear operation of the modulator in the ultra-wideband range, and seamless connection with peripheral drive / amplifier circuits.

[0069] According to one embodiment of the present invention, referring to Figure 4 The first integrated photodetector 210 and the second integrated photodetector 310 are single-row carrier photodetectors.

[0070] According to one embodiment of the present invention, the single-row carrier photodetector includes a substrate structure 2010, an epitaxial structure 2020, and a metal extraction structure 2030. The substrate structure 2010 is connected to the epitaxial structure 2020. The epitaxial structure 2020 includes an InGaAsP waveguide layer 2021, an InP drift layer 2022, and an InGaAs absorption layer 2023. The InGaAsP waveguide layer 2021 is connected to the substrate structure 2010, and the InP drift layer 2022 is connected to the InGaAsP waveguide layer 2023. 21. The InGaAs absorption layer 2023 is connected to the InP drift layer 2022. The metal extraction structure 2030 includes a first metal element 2031, a second metal element 2032, and a BCB buffer element 2033. The first end of the first metal element 2031 is connected to the substrate structure 2010. The first end of the second metal element 2032 is connected to the InGaAs absorption layer 2023. The BCB buffer element 2033 is disposed below the second end of the first metal element 2031 and the second end of the second metal element 2032.

[0071] Understandably, the InGaAs absorption layer 2023 employs a stepped doping concentration, with a lower concentration near the drift layer and a higher concentration on the other side. This facilitates rapid electron transfer to the drift layer, improving the detection bandwidth and saturation power. The InP drift layer 2022, serving as the cladding for the InGaAsP waveguide layer 2021, provides a high-speed, low-scattering drift channel for photogenerated carriers. Furthermore, its refractive index matches the underlying waveguide layer, helping to confine the optical field and allowing light energy to spread more uniformly to the absorption layer. This effectively avoids early saturation caused by excessively high local light intensity, thereby improving the overall saturation output power of the device. The InGaAsP waveguide layer 2021, acting as the optical input coupling layer, efficiently and uniformly guides the incident light signal into the absorption region, ensuring optimized optical field distribution. Below the first metal element 2031 and the second metal element 2032, a BCB buffer element 2033 serves as a buffer layer, effectively reducing the parasitic capacitance between the metal electrodes and the semiconductor material, thus improving the RC bandwidth of the single-row carrier photodetector.

[0072] In this UTC-PD, incident light is absorbed in the InGaAs absorption layer 2023, generating only electrons as useful charge carriers. These photogenerated electrons are rapidly injected into the InP drift layer 2022 with the assistance of an internal electric field within the absorption layer, and then traverse at extremely high saturation drift velocities. Combined with the reduced parasitic capacitance of the BCB buffer layer, this structure achieves a combination of ultra-high 3dB optoelectronic bandwidth (greater than 200GHz) and high saturation output power (greater than 0dBm), meeting the requirements of the fiber-to-wireless converged communication system based on integrated photonics proposed in this invention.

[0073] In one embodiment, the InGaAs absorption layer 2023 includes an InGaAs first layer, an InP cliff layer, and an InGaAs second layer, with the InP cliff layer disposed between the InGaAs first layer and the InGaAs second layer. The InGaAs first layer is disposed on the side closer to the second metal member 2032, and the InGaAs second layer is disposed on the side closer to the InP drift layer 2022.

[0074] The InP cliff layer increases the electric field strength at the heterojunction and extends the electric field into the InGaAs absorption layer 2023, reducing the transit time and accumulation of electrons in the InGaAs absorption layer 2023 and increasing the saturated output power, thereby meeting the communication system requirements for optical fiber communication and wireless communication proposed in this invention.

[0075] At the RF repeater 200, the first integrated photodetector 210, with its high bandwidth, ensures distortion-free response to the heterodyne beat frequency of the optical baseband signal and the optical local oscillator signal, directly generating a pure, high-power terahertz target electrical signal (e.g., 300 GHz). High saturation power ensures linear operation even with high input optical power (amplified by the first fiber amplifier 410), providing sufficient RF power to drive subsequent terahertz amplifiers.

[0076] At the baseband receiver 300, the second integrated photodetector 310 has a high bandwidth that ensures the complete reproduction of the high-speed modulated optical intermediate frequency signal; its high linearity ensures that no nonlinear distortion is introduced when receiving the signal amplified by the second fiber amplifier 510, providing a high-quality electrical signal for subsequent digital signal processing.

[0077] This invention provides a communication method for fiber optic and wireless communication based on integrated photonics, referring to... Figure 5 The process includes the following steps.

[0078] Step 10: At the baseband transmitter 100, the original electrical signal is converted into an optical baseband signal by the first integrated electro-optic modulator 110.

[0079] Step 20: The optical baseband signal is transmitted to the radio frequency relay terminal 200 through the first optical fiber link 400.

[0080] Step 30: At the radio frequency relay terminal 200, the optical baseband signal is converted into a target electrical signal in the target terahertz frequency band by the first integrated photodetector 210, and the target electrical signal is wirelessly transmitted through the wireless transmission module 230.

[0081] Step 40: Receive the target electrical signal through the wireless receiving module 240, and convert the target electrical signal into an optical intermediate frequency signal using the second integrated electro-optic modulator 260.

[0082] Step 50: The optical intermediate frequency signal is transmitted to the baseband receiver 300 through the second optical fiber link 500.

[0083] Step 60: At the baseband receiver 300, the optical intermediate frequency signal is converted into an output electrical signal by the second integrated photodetector 310.

[0084] In step 10, at the baseband transmitter 100, the original electrical signal to be transmitted is input to the first integrated electro-optic modulator 110. Simultaneously, a highly stable laser provides a continuous optical carrier for the first integrated electro-optic modulator 110. The first integrated electro-optic modulator 110 completes the electro-optic conversion based on the original electrical signal to generate an optical baseband signal.

[0085] In step 20, the generated optical baseband signal is injected into the first optical fiber link 400. This link typically includes transmission optical fibers and an optical fiber amplifier located at a remote end to ensure that the signal retains sufficient power after long-distance transmission. The optical signal is transmitted at high speed to the radio frequency repeater 200 in the optical fiber link with extremely low loss and low latency.

[0086] In step 30, at the radio frequency relay end 200, the first integrated photodetector 210 receives the optical baseband signal from the optical fiber. In a preferred embodiment, this signal is coherently combined with a local optical oscillator signal within the detector. The first integrated photodetector 210 directly converts the optical frequency difference between the two beams into a target electrical signal in a preset frequency band through the photoelectric effect. This target electrical signal is radiated into free space via the antenna of the wireless transmission module 230, thus achieving wireless coverage.

[0087] In step 40, the wireless receiving module 240 corresponding to the wireless transmitting module 230 captures the target electrical signal from the wireless transmitting module 230 and transmits it to the second integrated electro-optic modulator 260. The second integrated electro-optic modulator 260 uses an optical carrier provided by another laser to modulate the electrical signal onto the optical wave again to generate an optical intermediate frequency signal.

[0088] In step 50, the optical intermediate frequency signal is sent to the second optical fiber link 500 and transmitted back to the baseband receiver 300 on the network core side via optical fiber. Similarly, the second optical fiber link 500 also includes an optical fiber amplifier to compensate for return loss.

[0089] In step 60, at the baseband receiver 300, the second integrated photodetector 310 performs photoelectric conversion on the returned optical intermediate frequency signal to obtain a simulated output electrical signal.

[0090] The output electrical signal is then sent to the receiving and processing unit 320 for a full set of digital signal processing, including clock recovery, digital equalization, demodulation and decoding, and finally the original transmitted information is restored with high fidelity, completing the entire communication process.

[0091] By performing the above steps, the method of this invention connects the huge bandwidth and stable transmission capability of optical fiber with the high speed and flexible access capability of terahertz wireless through high-performance integrated photonic conversion technology, thereby realizing ultra-high speed and low latency communication transmission across the entire link.

[0092] Figure 6 This is a schematic diagram of the structure of the electronic device provided by the present invention, such as... Figure 6As shown, the electronic device may include: a processor 610, a communications interface 620, a memory 630, and a communications bus 640, wherein the processor 610, the communications interface 620, and the memory 630 communicate with each other through the communications bus 640. The processor 610 can call logic instructions in the memory 630 to execute a communication method based on integrated photonics for fiber optic communication and wireless communication. The method includes: at a baseband transmitter, converting a raw electrical signal into an optical baseband signal using a first integrated electro-optic modulator; transmitting the optical baseband signal to a radio frequency repeater via a first optical fiber link; at the radio frequency repeater, converting the optical baseband signal into a target electrical signal in a target terahertz frequency band using a first integrated photodetector, and wirelessly transmitting the target electrical signal via a wireless transmitter module; receiving the target electrical signal via a wireless receiver module, and converting the target electrical signal into an optical intermediate frequency (IF) signal using a second integrated electro-optic modulator; transmitting the optical IF signal to a baseband receiver via a second optical fiber link; and at the baseband receiver, converting the optical IF signal into an output electrical signal using a second integrated photodetector.

[0093] Furthermore, the logical instructions in the aforementioned memory 630 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0094] On the other hand, the present invention also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer is able to execute a communication method based on integrated photonics for fiber optic communication and wireless communication. The method includes: at a baseband transmitter, converting a raw electrical signal into an optical baseband signal using a first integrated electro-optic modulator; transmitting the optical baseband signal to a radio frequency relay end via a first optical fiber link; at the radio frequency relay end, converting the optical baseband signal into a target electrical signal in a target terahertz frequency band using a first integrated photodetector, and wirelessly transmitting the target electrical signal via a wireless transmitter module; receiving the target electrical signal via a wireless receiver module, and converting the target electrical signal into an optical intermediate frequency signal using a second integrated electro-optic modulator; transmitting the optical intermediate frequency signal to a baseband receiver end via a second optical fiber link; and at the baseband receiver end, converting the optical intermediate frequency signal into an output electrical signal using a second integrated photodetector.

[0095] In another aspect, the present invention also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements a communication method for fiber optic communication and wireless communication based on integrated photonics. The method includes: at a baseband transmitter, converting a raw electrical signal into an optical baseband signal using a first integrated electro-optic modulator; transmitting the optical baseband signal to a radio frequency relay end via a first optical fiber link; at the radio frequency relay end, converting the optical baseband signal into a target electrical signal in a target terahertz frequency band using a first integrated photodetector, and wirelessly transmitting the target electrical signal via a wireless transmitter module; receiving the target electrical signal via a wireless receiver module, and converting the target electrical signal into an optical intermediate frequency (IF) signal using a second integrated electro-optic modulator; transmitting the optical IF signal to a baseband receiver end via a second optical fiber link; and at the baseband receiver end, converting the optical IF signal into an output electrical signal using a second integrated photodetector.

[0096] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0097] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A communication system based on integrated photonics for fiber optic and wireless communication, characterized in that, include: The baseband transmitter (100) includes a first integrated electro-optic modulator (110), which is used to convert the original electrical signal of the baseband transmitter (100) into an optical baseband signal. A radio frequency relay (200) is connected to the baseband transmitter (100) via a first optical fiber link (400). The optical baseband signal is transmitted to the radio frequency relay (200) via the first optical fiber link (400). The radio frequency relay (200) includes a first integrated photodetector (210), a wireless transmitter module (230), a wireless receiver module (240), and a second integrated electro-optic modulator (260). The first integrated photodetector (210) is used to convert the received optical baseband signal into a target electrical signal in the target terahertz frequency band. The target electrical signal is transmitted through the wireless transmitter module (230), and the wireless receiver module (240) is used to receive the target electrical signal. The second integrated electro-optic modulator (260) is used to convert the target electrical signal into an optical intermediate frequency signal. The baseband receiver (300) is connected to the radio frequency relay (200) via a second optical fiber link (500). The optical intermediate frequency signal is transmitted to the baseband receiver (300) via the second optical fiber link (500). The baseband receiver (300) includes a second integrated photodetector (310), which is used to convert the optical intermediate frequency signal into an output electrical signal.

2. The communication system based on integrated photonics for fiber optic and wireless communication according to claim 1, characterized in that, The baseband transmitter (100) includes a signal source (130), a first integrated electro-optic modulator (110), and a first laser (120). The first laser (120) is used to generate an optical carrier at the transmitter. The signal source (130) is used to generate a raw electrical signal. The optical input terminal of the first integrated electro-optic modulator (110) is connected to the first laser (120), and the electrical input terminal is connected to the signal source (130). The first integrated electro-optic modulator (110) is used to convert the raw electrical signal and the optical carrier at the transmitter into an optical baseband signal.

3. The communication system based on integrated photonics for fiber optic and wireless communication according to claim 1, characterized in that, The radio frequency relay terminal (200) includes a second laser (220), a first integrated photodetector (210), a wireless transmitting module (230), a wireless receiving module (240), a third laser (250), and a second integrated electro-optic modulator (260). The second laser (220) is used to generate a local oscillator signal, and there is a preset frequency difference between the local oscillator signal and the optical baseband signal. The preset frequency difference corresponds to the carrier frequency of the target terahertz frequency band. The first integrated photodetector (210) is used to combine the local oscillator signal with the optical baseband signal amplified by the first optical fiber link (400) to generate a target electrical signal in the target terahertz frequency band. The wireless transmitting module (230) is connected to the first integrated photodetector (210) and is used to wirelessly transmit the target electrical signal; the wireless receiving module (240) is used to receive the target electrical signal; the third laser (250) is used to generate a receiving optical carrier; the optical input end of the second integrated electro-optic modulator (260) is connected to the third laser (250), and the electrical input end is connected to the wireless receiving module (240); the second integrated electro-optic modulator (260) is used to convert the receiving optical carrier and the target electrical signal into an optical intermediate frequency signal.

4. The communication system based on integrated photonics for fiber optic and wireless communication according to claim 1, characterized in that, The baseband receiver (300) includes a second integrated photodetector (310) and a receiving processing unit (320). The second integrated photodetector (310) is used to perform photoelectric conversion on the optical intermediate frequency signal amplified by the second optical fiber link (500) to generate an output electrical signal. The receiving processing unit (320) is connected to the second integrated photodetector (310).

5. The communication system based on integrated photonics for fiber optic communication and wireless communication according to any one of claims 1 to 4, characterized in that, The first optical fiber link (400) includes a first optical fiber (420) and a first optical fiber amplifier (410), wherein the first optical fiber amplifier (410) is disposed on the first optical fiber at one end near the radio frequency relay end (200); And / or, The second optical fiber link (500) includes a second optical fiber (520) and a second optical fiber amplifier (510), the second optical fiber amplifier (510) being disposed on the second optical fiber near the baseband receiver (300).

6. The communication system based on integrated photonics for optical fiber communication and wireless communication according to any one of claims 1 to 4, characterized in that, The first integrated electro-optic modulator (110) and the second integrated electro-optic modulator (260) are thin-film lithium niobate electro-optic modulators.

7. The communication system based on integrated photonics for fiber optic and wireless communication according to claim 6, characterized in that, The thin-film lithium niobate electro-optic modulator includes: The input end face coupler (1001), input low-loss optical waveguide (1002), input multimode interferometer (1003), modulation arm optical waveguide (1004), output multimode interferometer (1005), output low-loss optical waveguide (1006) and output end face coupler (1007) are connected in sequence. The modulation arm optical waveguide (1004) is provided with a coplanar waveguide traveling wave electrode (1008), which includes an electro-optic interaction region (10081). In a direction parallel to the surface of the electro-optic modulator substrate, the signal lines of the electro-optic interaction region (10081) facing the surface of the corresponding modulation arm optical waveguide (1004) are provided with multiple patterned slow wave electrode structures (10080).

8. The communication system based on integrated photonics for optical fiber communication and wireless communication according to any one of claims 1 to 4, characterized in that, The first integrated photodetector (210) and the second integrated photodetector (310) are single-row carrier photodetectors.

9. The communication system based on integrated photonics for fiber optic communication and wireless communication according to claim 8, characterized in that, The single-row carrier photodetector includes a substrate structure (2010), an epitaxial structure (2020), and a metal extraction structure (2030). The substrate structure (2010) is connected to the epitaxial structure (2020). The epitaxial structure (2020) includes an InGaAsP waveguide layer (2021), an InP drift layer (2022), and an InGaAs absorption layer (2023). The InGaAsP waveguide layer (2021) is connected to the substrate structure (2010), and the InP drift layer (2022) is connected to the InGaAsP waveguide layer (2021). The nGaAs absorber layer (2023) is connected to the InP drift layer (2022). The metal extraction structure (2030) includes a first metal element (2031), a second metal element (2032), and a BCB buffer element (2033). The first end of the first metal element (2031) is connected to the substrate structure (2010), the first end of the second metal element (2032) is connected to the InGaAs absorber layer (2023), and the BCB buffer element (2033) is disposed below the second end of the first metal element (2031) and the second end of the second metal element (2032).

10. A communication method based on integrated photonics for fiber optic communication and wireless communication, characterized in that, A communication system based on integrated photonics for optical fiber communication and wireless communication, applicable to any one of claims 1 to 9, comprising: At the baseband transmitter (100), the original electrical signal is converted into an optical baseband signal by the first integrated electro-optic modulator (110); The optical baseband signal is transmitted to the radio frequency relay end (200) through the first optical fiber link (400); At the radio frequency relay terminal (200), the optical baseband signal is converted into a target electrical signal in the target terahertz frequency band by the first integrated photodetector (210), and the target electrical signal is wirelessly transmitted through the wireless transmission module (230). The target electrical signal is received by the wireless receiving module (240), and the target electrical signal is converted into an optical intermediate frequency signal by the second integrated electro-optic modulator (260). The optical intermediate frequency signal is transmitted to the baseband receiver (300) through the second optical fiber link (500). At the baseband receiver (300), the optical intermediate frequency signal is converted into an output electrical signal by a second integrated photodetector (310).

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