Full-duplex terahertz and space laser fusion transmission system

Abstract

The invention discloses a full-duplex terahertz and space laser fusion transmission system, and relates to the field of terahertz communication and optical communication, and the system comprises an optical signal receiving and transmitting module which is used for intelligently selecting and switching a terahertz link or a space laser link according to a channel environment and a weather condition, an optical signal is transmitted to the terahertz / space laser optical fiber wireless conversion module or is received from the terahertz / space laser optical fiber wireless conversion module; the terahertz / space laser optical fiber wireless conversion module is used for completing carrier signal generation, data modulation, demodulation, amplification, splitting and combining and other processing on an optical domain and an electric domain; and the wireless transceiver module is used for transmitting or receiving the terahertz signal and the space laser signal in a wireless mode. According to the invention, the terahertz link or the space laser link can be switched to carry out signal transmission according to the channel condition and the weather environment, the anti-interference capability of the communication system is greatly improved, and stable and efficient communication in almost all-weather scenes such as rain, snow and fog is ensured.

Description

Technical Field

[0001] The present invention relates to the fields of terahertz communication and optical communication, and particularly to a full-duplex terahertz and space laser fusion transmission system. Background Art

[0002] In recent years, with the rapid development of communication technologies, the requirements of communication systems for high data transmission rate, low latency, high reliability, and wide-area coverage ability have been continuously increasing. Terahertz communication is considered to be one of the important candidate technologies for future 6G communication networks because of its ultra-large spectral bandwidth and high transmission rate. At the same time, free-space optical communication (FSO), as a wireless communication method based on laser beams, has advantages such as high confidentiality, high transmission rate, low power consumption, and no need for spectrum licensing, and is an effective complementary technology for broadband wireless communication.

[0003] However, there are limitations in using terahertz communication or free-space optical communication alone. Although terahertz communication can penetrate smoke, its performance will significantly decline in rainy and snowy environments. At the same time, terahertz links are easily affected by path loss and scattering effects. And free-space optical communication is prone to link interruption under environmental conditions such as smoke, haze, and atmospheric turbulence. In addition, to meet the high reliability requirements of future communication networks, it is difficult to adapt to complex and changeable actual application scenarios relying only on a certain communication technology.

[0004] The hardware structures of terahertz communication and free-space optical communication are quite different at the transmitter and receiver ends. Designing a unified system architecture to reduce hardware complexity is a key problem. The multi-modal coexistence and resource allocation problems of terahertz signals and laser signals need to be solved urgently, especially to achieve efficient link switching in different channel environments to improve system reliability. There are few full-duplex fusion transmission schemes for terahertz signals and laser signals in existing communication systems. Achieving simultaneous communication of uplink and downlink links under limited hardware resources is also an important research direction in the technical field. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a full-duplex terahertz and space laser fusion transmission system. The full-duplex terahertz and space laser fusion transmission system of the present invention adopts dual-link signal transmission of terahertz link and space laser link. When a signal interruption or other faults occur in one of the links, it can immediately switch to the other link, ensuring the stability of data transmission, achieving high-speed and highly reliable backup transmission, and enhancing the robustness of the system.

[0006] The present invention adopts the following technical solutions to solve the above technical problems:

[0007] A full-duplex terahertz and space laser fusion transmission system proposed according to the present invention includes at least one set of sequentially connected optical signal transceiver modules, terahertz / space laser fiber wireless conversion modules, and wireless transceiver modules; wherein,

[0008] The optical signal transceiver module is used for selecting and switching between the terahertz link and the space laser link. Among them, in the transmitting link, an optical signal is transmitted to the terahertz / space laser fiber wireless conversion module; in the receiving link, for the terahertz link, a single-sideband signal from the terahertz / space laser fiber wireless conversion module is received, and for the space laser link, an optical signal from the terahertz / space laser fiber wireless conversion module is received;

[0009] The terahertz / space laser fiber wireless conversion module is used for receiving the optical signal transmitted from the optical signal transceiver module in the transmitting link; wherein,

[0010] For the terahertz link, a radio frequency signal is used to drive the optical signal to generate a first-order sideband signal, forming an optical modulation signal. The optical modulation signal is divided into two signals, an odd-channel signal and an even-channel signal. The even-channel signal is beat to form a terahertz signal and the terahertz signal is amplified. The odd-channel signal is amplified, and these two signals are transmitted to the wireless transceiver module; these two signals refer to the amplified terahertz signal and the amplified odd-channel signal;

[0011] For the space laser link, the optical signal is amplified and then transmitted to the wireless transceiver module;

[0012] It is used in the receiving link:

[0013] For the terahertz link, it is used to modulate the terahertz signal input by the wireless transceiver module onto an optical carrier signal, forming an optical bandpass signal. The optical bandpass signal is filtered to remove any one sideband, forming a single-sideband signal and transmitting it to the optical signal transceiver module;

[0014] For the space laser link, the optical signal input by the wireless transceiver module is amplified and then transmitted to the optical signal transceiver module;

[0015] The wireless transceiver module is used for wirelessly transmitting one terahertz signal and one optical signal from the terahertz / space laser fiber wireless conversion module in the transmitting link; wherein, one terahertz signal refers to the amplified terahertz signal output by the terahertz / space laser fiber wireless conversion module, and one optical signal refers to the amplified odd-channel signal output by the terahertz / space laser fiber wireless conversion module or the optical signal output by the space laser link;

[0016] In the receiving link, a terahertz signal and an optical signal input externally in a wireless manner are received and sent to the terahertz / free-space laser fiber wireless conversion module.

[0017] As a further optimization scheme of a full-duplex terahertz and free-space laser fusion transmission system according to the present invention, the optical signal transceiver module includes an optical module SFP+ and a link selection switch; wherein,

[0018] The link selection switch is used to select and switch between the terahertz link and the free-space laser link;

[0019] The optical module SFP+ is used to convert the electrical signal from the external main board into an optical signal and transmit the optical signal to the terahertz / free-space laser fiber wireless conversion module through an optical fiber in the transmitting link; in the receiving link, for the terahertz link, the single-sideband signal from the terahertz / free-space laser fiber wireless conversion module is received through the optical fiber, and for the free-space laser link, the optical signal from the terahertz / free-space laser fiber wireless conversion module is received through the optical fiber; and the single-sideband signal or the optical signal is converted into an electrical signal for further processing by the external main board.

[0020] As a further optimization scheme of a full-duplex terahertz and free-space laser fusion transmission system according to the present invention, the terahertz / free-space laser fiber wireless conversion module includes a first erbium-doped fiber amplifier, a phase modulator, an electro-absorption modulator, an interleaver filter, a second erbium-doped fiber amplifier, a photodetector, a first low-noise amplifier, an optical coupler, a third erbium-doped fiber amplifier, a second low-noise amplifier, an intensity modulator, an external cavity laser, a fourth erbium-doped fiber amplifier, a tunable optical filter, and a fifth erbium-doped fiber amplifier; wherein,

[0021] In the transmitting link,

[0022] The first erbium-doped fiber amplifier is used to amplify the optical signal to be transmitted in the terahertz link;

[0023] The electro-absorption modulator and the phase modulator are used to drive the amplified optical signal to be transmitted to generate a first-order sideband signal, forming an optical modulation signal;

[0024] The interleaver filter is used to separate the optical modulation signal into odd channels and even channels, obtaining an odd-channel signal and an even-channel signal; wherein, the odd-channel signal is the baseband signal in the optical modulation signal, and the even-channel signal is the two first-order sideband signals in the optical modulation signal;

[0025] The second erbium-doped fiber amplifier is used to amplify the even-channel signal;

[0026] The photodetector is used to perform beat frequency processing on the amplified even-channel signal to generate a terahertz signal;

[0027] The first low-noise amplifier is used to amplify the terahertz signal;

[0028] The optical coupler is used to transmit the odd-channel signal of the terahertz link and the optical signal of the spatial laser link into the same optical fiber;

[0029] The third erbium-doped fiber amplifier is used to amplify the odd-channel signal of the terahertz link or the optical signal of the spatial laser link in the optical fiber;

[0030] In the receiving link,

[0031] The second low-noise amplifier is used to amplify the terahertz signal input by the wireless transceiver module in the terahertz link;

[0032] The intensity modulator and the external cavity laser are used to modulate the amplified terahertz signal onto the optical carrier signal to form an optical bandpass signal;

[0033] The fourth erbium-doped fiber amplifier is used to amplify the optical bandpass signal;

[0034] The tunable optical filter is used to filter out any one of the sidebands of the amplified optical bandpass signal to obtain a single-sideband signal;

[0035] The fifth erbium-doped fiber amplifier is used to amplify the optical signal input from the wireless transceiver module in the spatial laser link.

[0036] As a further optimization scheme of the full-duplex terahertz and spatial laser fusion transmission system described in the present invention,

[0037] The wireless transceiver module includes an orthomode transducer, an optical circulator, a terahertz signal transceiver antenna, and an optical signal transceiver antenna; wherein,

[0038] The orthomode transducer is used to receive the amplified terahertz signal output from the terahertz / spatial laser fiber wireless conversion module in the transmitting link and output the amplified terahertz signal to the terahertz transceiver antenna for transmission; in the receiving link, it receives the terahertz signal transmitted by the terahertz signal transceiver antenna and outputs it to the terahertz / spatial laser fiber wireless conversion module;

[0039] The optical circulator is used to receive the amplified odd-channel signal output from the terahertz / spatial laser fiber wireless conversion module or the optical signal output from the spatial laser link in the transmitting link and output the amplified odd-channel signal or the optical signal output from the spatial laser link to the optical signal transceiver antenna; in the receiving link, it receives the optical signal transmitted by the optical signal transceiver antenna and outputs the optical signal to the terahertz / spatial laser fiber wireless conversion module;

[0040] A terahertz signal transceiver antenna is used to wirelessly transmit the amplified terahertz signal output from a terahertz / spatial laser fiber wireless conversion module in the transmitting link; in the receiving link, it is used to wirelessly receive an externally input terahertz signal and send it to the terahertz / spatial laser fiber wireless conversion module.

[0041] An optical signal transceiver antenna is used to wirelessly transmit the amplified odd-channel signal output from a terahertz / spatial laser fiber wireless conversion module or the optical signal output from a spatial laser link in the transmitting link; in the receiving link, it is used to wirelessly receive an externally input optical signal and send it to the terahertz / spatial laser fiber wireless conversion module.

[0042] As a further optimization scheme of the full-duplex terahertz and spatial laser fusion transmission system described in the present invention, two orthogonally polarized terahertz signals in the transmitting link and the receiving link are combined into one signal via an orthomode transducer, and mode separation is generated to realize the transmission and reception of terahertz signals using only one antenna; two optical signals in the transmitting link and the receiving link pass through an optical circulator to realize the separation and unidirectional transmission of the uplink and downlink optical signals, and the transmission and reception of optical signals using only one antenna are realized.

[0043] Compared with the prior art, the present invention adopts the above technical solutions and has the following technical effects:

[0044] (1) The full-duplex terahertz and spatial laser fusion transmission system disclosed by the present invention can select a terahertz link or a spatial laser link for signal transmission according to the channel conditions and link environment, making up for the limitations of a single terahertz link or a single spatial laser link, greatly improving the anti-interference ability of the communication system, and ensuring stable and efficient communication in almost all-weather scenarios such as rain, snow, and fog.

[0045] (2) The full-duplex terahertz and spatial laser fusion transmission system of the present invention adopts dual-link signal transmission of a terahertz link and a spatial laser link. When a signal interruption or other faults occur in one of the links, it can immediately switch to the other link, ensuring the stability of data transmission, realizing high-speed and highly reliable backup transmission, and enhancing the robustness of the system. Description of the Drawings

[0046] Figure 1 It is a module schematic diagram of a full-duplex terahertz and spatial laser fusion transmission system provided by an embodiment of the present invention;

[0047] Figure 2 It is another module schematic diagram of a full-duplex terahertz and spatial laser fusion transmission system provided by an embodiment of the present invention;

[0048] Figure 3Block diagram of a full-duplex terahertz and spatial laser fusion transmission system provided by an embodiment of the present invention;

[0049] Figure 4 Block diagram of a full-duplex structure of a full-duplex terahertz and spatial laser fusion transmission system provided by an embodiment of the present invention;

[0050] Figure 5 Spectral schematic diagrams of corresponding nodes in the link of a full-duplex terahertz and spatial laser fusion transmission system provided by an embodiment of the present invention; wherein, (a) is the spectral schematic diagram of the first node A located between the first phase modulator 2a2 and the first bandpass filter 2a4, (b) is the spectral schematic diagram of the second node B located between the first bandpass filter 2a4 and the second erbium-doped fiber amplifier 2a5, (c) is the spectral schematic diagram of the third node C located between the first bandpass filter 2a4 and the first optical coupler 2a8, (d) is the spectral schematic diagram of the fourth node D located between the second intensity modulator 5a2 and the sixth erbium-doped fiber amplifier 5a4, (e) is the spectral schematic diagram of the fifth node E located between the second tunable optical filter 5a5 and the link selection switch 63 at the Rx end of the second optical signal transceiver module 6.

[0051] Explanation of reference numerals:

[0052] 1 - First optical signal transceiver module, 2 - First terahertz / spatial laser fiber wireless conversion module, 3 - First wireless transceiver module, 4 - Second wireless transceiver module, 5 - Second terahertz / spatial laser fiber wireless conversion module, 6 - Second optical signal transceiver module;

[0053] 11 - First optical module SFP+, 12 - Link selection switch at the Tx end of the first optical signal transceiver module 1, 13 is the link selection switch at the Rx end of the first optical signal transceiver module 1, 2a1 - First erbium-doped fiber amplifier, 2a2 - First phase modulator, 2a3 - First electro-absorption modulator, 2a4 - First bandpass filter, 2a5 - Second erbium-doped fiber amplifier, 2a6 - First photodetector, 2a7 - First low-noise amplifier, 2a8 - First optical coupler, 2a9 - Third erbium-doped fiber amplifier, 31 - First orthomode transducer, 32 First terahertz signal transceiver antenna, 33 - First optical circulator, 34 - First optical signal transceiver antenna, 2b1 is the second low-noise amplifier, 2b2 - First intensity modulator, 2b3 - First external cavity laser, 2b4 - Fourth erbium-doped fiber amplifier, 2b5 - First tunable optical filter, 2b6 - Fifth erbium-doped fiber amplifier,

[0054] A, B, C, D, E are the first to fifth nodes respectively;

[0055] 41 - Second terahertz signal transceiver antenna, 42 - Second orthogonal mode converter;

[0056] 5a1 - Third low noise amplifier, 5a2 - Second intensity modulator, 5a3 - Second external cavity laser, 5a4 - Sixth erbium-doped fiber amplifier, 5a5 - Second tunable optical filter, 5a6 - Seventh erbium-doped fiber amplifier,

[0057] 5b1 - Eighth erbium-doped fiber amplifier, 5b2 - Second phase modulator, 5b3 - Second electro-absorption modulator, 5b4 - Second bandpass filter, 5b5 - Ninth erbium-doped fiber amplifier, 5b6 - Second photodetector, 5b7 - Fourth low noise amplifier, 5b8 - Second optical coupler, 5b9 - Tenth erbium-doped fiber amplifier;

[0058] 43 - Second optical signal transceiver antenna, 44 - Second optical circulator, 61 - Second optical module SFP+, 62 - Link selection switch at the Tx end of the second optical signal transceiver module 6, 63 - Link selection switch at the Rx end of the second optical signal transceiver module 6. Detailed implementation mode

[0059] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0060] Figure 1 It is a module schematic diagram of a full-duplex terahertz and space laser fusion transmission system provided by an embodiment of the present invention. In the terahertz and space laser fusion transmission system of this embodiment, it can select a terahertz link or a space laser link for signal transmission according to the channel conditions and link environment, making up for the limitations of a single terahertz link or a single space laser link, greatly improving the anti-interference ability of the communication system, and ensuring stable and efficient communication in almost all-weather scenarios such as rain, snow, and fog; the terahertz and space laser fusion transmission system in this embodiment adopts dual-link signal transmission of the terahertz link and the space laser link. When a signal interruption or other faults occur in one of the links, it can immediately switch to the other link, ensuring the stability of data transmission, realizing high-speed and highly reliable backup transmission, and enhancing the robustness of the system.

[0061] The system corresponding to this embodiment includes a group of successively connected optical signal transceiver modules, terahertz / space laser fiber wireless conversion modules, and wireless transceiver modules;

[0062] The optical signal transceiver module is used for selecting and switching between a terahertz link and a free-space laser link. In the transmitting link, it transmits an optical signal to the terahertz / free-space laser fiber wireless conversion module. In the receiving link, for the terahertz link, it receives a single-sideband signal from the terahertz / free-space laser fiber wireless conversion module, and for the free-space laser link, it receives an optical signal from the terahertz / free-space laser fiber wireless conversion module.

[0063] The terahertz / free-space laser fiber wireless conversion module is used for receiving the optical signal transmitted from the optical signal transceiver module in the transmitting link. Among them,

[0064] For the terahertz link, it drives an optical signal through a radio frequency signal to generate a first-order sideband signal, forms an optical modulation signal, divides the optical modulation signal into two signals: an odd-channel signal and an even-channel signal, beats the even-channel signal to form a terahertz signal and amplifies the terahertz signal, amplifies the odd-channel signal, and transmits these two signals to the wireless transceiver module. These two signals refer to the amplified terahertz signal and the amplified odd-channel signal.

[0065] For the free-space laser link, it amplifies the optical signal and then transmits it to the wireless transceiver module.

[0066] It is used in the receiving link:

[0067] For the terahertz link, it modulates the terahertz signal input by the wireless transceiver module onto an optical carrier signal, forms an optical bandpass signal, filters any one sideband from the optical bandpass signal, forms a single-sideband signal and transmits it to the optical signal transceiver module.

[0068] For the free-space laser link, it amplifies the optical signal input by the wireless transceiver module and then transmits it to the optical signal transceiver module.

[0069] The wireless transceiver module is used for wirelessly transmitting a terahertz signal and an optical signal from the terahertz / free-space laser fiber wireless conversion module in the transmitting link. Among them, one terahertz signal refers to the amplified terahertz signal output by the terahertz / free-space laser fiber wireless conversion module, and one optical signal refers to the amplified odd-channel signal output by the terahertz / free-space laser fiber wireless conversion module or the optical signal output by the free-space laser link.

[0070] In the receiving link, it wirelessly receives an external input terahertz signal and an optical signal and sends them to the terahertz / free-space laser fiber wireless conversion module.

[0071] As Figure 3 shown, in one embodiment, the optical signal transceiver module includes an optical module SFP+ and a link selection switch.

[0072] The link selection switch is used to select and switch between the terahertz link and the free-space laser link according to the channel conditions and weather environment; the commercial optical module SFP+ is used in the transmitting link to convert the electrical signal from the external main board into an optical signal and transmit the optical signal through the optical fiber to the terahertz / free-space laser fiber-wireless conversion module; in the receiving link, for the terahertz link, the single-sideband signal from the terahertz / free-space laser fiber-wireless conversion module is received through the optical fiber, and for the free-space laser link, the optical signal from the terahertz / free-space laser fiber-wireless conversion module is received through the optical fiber; and the single-sideband signal or the optical signal is converted into an electrical signal.

[0073] As Figure 3 shown, in one embodiment, the terahertz / free-space laser fiber-wireless conversion module includes a first erbium-doped fiber amplifier, a first phase modulator, a first electro-absorption modulator, a first interleaver filter, a second erbium-doped fiber amplifier, a first photodetector, a first low-noise amplifier, a first optical coupler, a third erbium-doped fiber amplifier, a second low-noise amplifier, a first intensity modulator, a first external cavity laser, a fourth erbium-doped fiber amplifier, a first tunable optical filter, and a fifth erbium-doped fiber amplifier;

[0074] For the transmitting link, the first erbium-doped fiber amplifier is used to amplify the optical signal to be transmitted in the terahertz link; the first electro-absorption modulator and the first phase modulator are used to drive the optical signal to be transmitted to generate a first-order sideband signal, forming an optical modulation signal; the first interleaver filter is used to separate the optical modulation signal into odd channels and even channels, obtaining an odd-channel signal and an even-channel signal; wherein, the odd-channel signal is the baseband signal in the optical modulation signal, and the even-channel signal is the two first-order sideband signals in the optical modulation signal; the second erbium-doped fiber amplifier is used to amplify the even-channel signal, the first photodetector is used to perform beat-frequency processing on the even-channel signal to generate the terahertz signal; the first low-noise amplifier is used to amplify the terahertz signal; the first optical coupler is used to transmit the odd-channel signal in the terahertz link and the optical signal in the free-space laser link to the same optical fiber; the third erbium-doped fiber amplifier is used to amplify the odd-channel signal in the terahertz link or the optical signal in the free-space laser link in the optical fiber;

[0075] For the receiving link, the second low-noise amplifier is used to amplify the terahertz signal input by the wireless transceiver module in the terahertz link; the first intensity modulator and the first external cavity laser are used to modulate the terahertz signal onto an optical carrier signal to form the optical bandpass signal; the fourth erbium-doped fiber amplifier is used to amplify the optical bandpass signal; the first tunable optical filter is used to filter out any one of the sidebands of the optical bandpass signal to obtain the single-sideband signal. The fifth erbium-doped fiber amplifier is used to amplify the optical signal in the free-space optical link.

[0076] As Figure 3 shown, in one embodiment, the wireless transceiver module includes a first orthomode transducer, a first optical circulator, a first terahertz signal transceiver antenna, and a first optical signal transceiver antenna;

[0077] The first orthomode transducer is configured to, in the transmitting link, receive the amplified terahertz signal output from the terahertz / free-space optical fiber wireless conversion module and output the amplified terahertz signal to the first terahertz transceiver antenna for transmission; in the receiving link, receive the terahertz signal transmitted by the first terahertz signal transceiver antenna and output it to the terahertz / free-space optical fiber wireless conversion module; the first optical circulator is configured to, in the transmitting link, receive the amplified odd-channel signal output from the terahertz / free-space optical fiber wireless conversion module or the optical signal output from the free-space optical link and output the amplified odd-channel signal or the optical signal output from the free-space optical link to the first optical signal transceiver antenna; in the receiving link, receive the optical signal transmitted by the first optical signal transceiver antenna and output the optical signal to the terahertz / free-space optical fiber wireless conversion module; the first terahertz signal transceiver antenna is configured to, in the transmitting link, wirelessly transmit the amplified terahertz signal output from the terahertz / free-space optical fiber wireless conversion module; in the receiving link, wirelessly receive the externally input terahertz signal and send it to the terahertz / free-space optical fiber wireless conversion module; the first optical signal transceiver antenna is configured to, in the transmitting link, wirelessly transmit the amplified odd-channel signal output from the terahertz / free-space optical fiber wireless conversion module or the optical signal output from the free-space optical link; in the receiving link, wirelessly receive the externally input optical signal and send it to the terahertz / free-space optical fiber wireless conversion module.

[0078] Figure 2 Another schematic diagram of a module of a full-duplex terahertz and free-space optical fusion transmission system provided by an embodiment of the present invention. The system includes two groups of optically-signal transceiver modules, terahertz / free-space optical fiber wireless conversion modules, and wireless transceiver modules that are connected in sequence, and can achieve full-duplex transmission of signals;

[0079] As shown Figure 4 The specific structure of a full-duplex terahertz and spatial laser fusion transmission system corresponding to an embodiment of the present invention is given, including two groups of optically-signal transceiver modules, terahertz / spatial laser fiber wireless conversion modules, and wireless transceiver modules connected in sequence;

[0080] Specifically, the uplink includes: the first optically-signal transceiver module 1, the first terahertz / spatial laser fiber wireless conversion module 2, the first wireless transceiver module 3, the second wireless transceiver module 4, the second terahertz / spatial laser fiber wireless conversion module 5, and the second optically-signal transceiver module 6;

[0081] The downlink includes: the second optically-signal transceiver module 6, the second terahertz / spatial laser fiber wireless conversion module 5, the second wireless transceiver module 4, the first wireless transceiver module 3, the first terahertz / spatial laser fiber wireless conversion module 2, and the first optically-signal transceiver module 1;

[0082] As shown Figure 5 The spectral schematic diagrams of corresponding nodes in the link of a full-duplex terahertz and spatial laser fusion transmission system corresponding to a specific embodiment of the present invention are given, Figure 5 The five diagrams (a), (b), (c), (d), and (e) in Figure 4 correspond to the first node A, the second node B, the third node C, the fourth node D, and the fifth node E in

[0083] When the uplink is working, in the first optical signal transceiver module 1, the first optical module SFP+11 converts the electrical signal from the external main board into an optical signal, and selects and switches the terahertz link or the space laser link through the link selection switch 12 at the Tx end of the first optical signal transceiver module 1. Moreover, the link selection situation of the link selection switch 12 at the Tx end of the first optical signal transceiver module 1 is the same as that of the link selection switch 63 at the Rx end of the second optical signal transceiver module 6. If the link selection switch 12 at the Tx end of the first optical signal transceiver module 1 selects the terahertz link, the optical signal to be transmitted enters the first terahertz / space laser fiber wireless conversion module 2. The optical signal to be transmitted is preliminarily power-amplified by the first erbium-doped fiber amplifier 2a1 to improve the quality of subsequent signal processing. Subsequently, the first phase modulator 2a2 and the first electro-absorption modulator 2a3 perform phase modulation on the optical signal to be transmitted, and the radio frequency signal drives the optical signal to be transmitted to generate the first-order sideband, forming an optical modulation signal. For example, if the frequency of the optical signal transmitted by the first optical signal transceiver module 1 is f2 and the frequency of the radio frequency signal is f clock = 50 GHz, then the radio frequency signal f clock drives the optical signal to be transmitted to generate the first-order sideband, with frequencies f1 and f3, as shown in Figure 5 Figure (a). Among them, f2 - f1 = 50 GHz, f3 - f2 = 50 GHz, fΔ = f3 - f = 100 GHz. Then the frequency of the subsequent beat-generated terahertz signal is 100 GHz. The optical modulation signal is separated into an odd-channel signal and an even-channel signal by the first interleaver 2a4. The even-channel signal is the first-order sideband signal in the optical modulation signal, as shown in Figure 5 Figure (b). The odd-channel signal is the baseband signal in the optical modulation signal, as shown in Figure 5As shown in figure (c), the odd communication signal and the even channel signal are transmitted in two paths. The even channel signal is amplified in power by the second erbium-doped fiber amplifier 2a5, then subjected to beat frequency through the first photodetector 2a6 to convert the optical signal into a terahertz signal with a frequency of 100 GHz. The obtained terahertz signal is amplified by the first low-noise amplifier 2a7 and transmitted into the first wireless transceiver module. The terahertz signal is input from the horizontal polarization port of the first orthomode transducer 31 and output from the common port of the first terahertz orthomode transducer 31, and then transmitted wirelessly through the first terahertz transceiver antenna 32. The first optical coupler 2a8 transmits the odd channel signal in the terahertz link and the optical signal in the free-space optical link into the same optical fiber. After passing through the first optical coupler 2a8, the odd channel signal is amplified in power by the third erbium-doped fiber amplifier 2a9 and enters the first wireless transceiver module 3. This odd channel signal is input from the first port of the first optical circulator 33, output from the second port of the first optical circulator 33 and transmitted through the first optical signal transceiver antenna 34. If the link selection switch 12 at the Tx end of the first optical signal transceiver module 1 selects the free-space optical link, the transmission path of the optical signal to be transmitted is the same as that of the odd channel signal in the terahertz link. Specifically, the optical signal to be transmitted enters the first terahertz / free-space optical fiber wireless conversion module 2, is amplified in power by the third erbium-doped fiber amplifier 2a9 after passing through the first optical coupler 2a8, and enters the first wireless transceiver module 3. This optical signal to be transmitted is input from the first port of the first optical circulator 33, output from the second port of the first optical circulator 33 and transmitted through the first optical signal transceiver antenna 34. The first optical signal transceiver antenna 34 can transmit the odd channel signal in the terahertz link or the optical signal in the free-space optical link according to the link selection situation. In the second wireless transceiver module 4, in the terahertz link, the second terahertz signal transceiver antenna 41 receives the terahertz signal transmitted from the first terahertz signal transceiver antenna 32 in the first wireless transceiver module 3. This terahertz signal is input from the common port of the second orthomode transducer 41 and output from the horizontal polarization port of the second orthomode transducer 41, and enters the second terahertz / free-space optical fiber wireless conversion module 5, where it is amplified by the third low-noise amplifier 5a1. The second intensity modulator 5a2 and the second external cavity laser 5a3 modulate this terahertz signal onto the optical signal to form an optical bandpass signal. Specifically, the frequency of the terahertz signal is 100 GHz. If the frequency of the optical carrier signal provided by the second external cavity laser 5a3 is f5, then after receiving the terahertz signal and the optical carrier signal, the second intensity modulator 5a2 modulates the terahertz signal onto the optical carrier signal to generate two first-order sideband signals with frequencies of f4 = f5 - fΔ and f6 = f5 + fΔ, as Figure 5as shown in figure (d); the optical passband signal is amplified in signal power by the sixth erbium-doped optical fiber amplifier 5a4, and then any sideband in the optical bandpass signal is filtered out by the second tunable optical filter 5a5 to obtain a single-sideband signal. Specifically, if the sideband corresponding to the high frequency f6 is filtered out, the obtained single-sideband signal is as shown in Figure 5 figure (e); this single-sideband signal enters the second optical signal transceiver module 6, passes through the link selection switch 63 at the Rx end of the second optical signal transceiver module 6 and then enters the second optical module SFP+61. The first optical module SFP+61 converts the optical signal into an electrical signal for further processing by an external main board; in the space laser link, the second optical signal transceiver antenna 43 receives the optical signal transmitted by the first optical signal transceiver antenna 34 in the first wireless transceiver module 3. This optical signal is input from the second port of the second optical circulator 44 and output from the third port of the second optical circulator 44, amplified in power by the seventh erbium-doped optical fiber amplifier 5a6, enters the second optical signal transceiver module 6, passes through the link selection switch 63 at the Rx end of the second optical signal transceiver module 6 and then enters the second optical module SFP+61. The second optical module SFP+61 converts the optical signal into an electrical signal for further processing by an external main board.

[0084] When the downlink is working, in the second optical signal transceiver module 6, the second optical module SFP+61 converts the electrical signal from the external main board into an optical signal, and the link selection switch 62 at the Tx end of the second optical signal transceiver module 6 selects and switches between the terahertz link and the space laser link. The link selection situation of the link selection switch 62 at the Tx end of the second optical signal transceiver module 6 is the same as that of the link selection switch 13 at the Rx end of the first optical signal transceiver module 1. If the link selection switch 62 at the Tx end of the second optical signal transceiver module 6 selects the terahertz link, the optical signal to be transmitted enters the second terahertz / space laser fiber wireless conversion module 5. The optical signal to be transmitted is preliminarily amplified in power by the eighth erbium-doped optical fiber amplifier 5b1 to improve the quality of subsequent signal processing. Subsequently, the second phase modulator 5b2 and the second electro-absorption modulator 5b3 perform phase modulation on the optical signal to be transmitted, and the radio frequency signal f clockDrive the optical signal to be transmitted to generate first-order sidebands to form an optical modulation signal. This optical signal is separated into an odd-channel signal and an even-channel signal by the second bandpass filter 5b4 and enters different processing paths respectively. Among them, the even-channel signal is power-enhanced by the ninth erbium-doped fiber amplifier 5b5, and then subjected to beat frequency by the second photodetector 5b6 to convert the optical signal into a terahertz signal. The obtained terahertz signal is amplified by the fourth low-noise amplifier 5b7 and transmitted to the second wireless transceiver module 4. The terahertz signal is input from the vertical polarization port of the second orthomode transducer 42 and output from the common port of the second orthomode transducer 42, and then wirelessly transmitted through the second terahertz signal transceiver antenna 41; the second optical coupler 5b8 transmits the odd-channel signal in the terahertz link and the optical signal in the spatial laser link to the same optical fiber. After passing through the second optical coupler 5b8, the odd-channel signal is power-enhanced by the tenth erbium-doped fiber amplifier 5b9 and enters the second wireless transceiver module 4. The odd-channel signal is input from the first port of the second optical circulator 44, output from the second port of the second optical circulator 44 and wirelessly transmitted through the second optical signal transceiver antenna 43; if the link selection switch 62 at the Tx end of the second optical signal transceiver module 6 selects the spatial laser link, the transmission path of the optical signal to be transmitted is the same as that of the odd-channel signal in the terahertz link. Specifically, the optical signal to be transmitted enters the second terahertz / spatial laser fiber wireless conversion module 5, is power-enhanced by the tenth erbium-doped fiber amplifier 5b9 after passing through the second optical coupler 5b8, enters the second wireless transceiver module 4, the signal is input from the first port of the second optical circulator 44, output from the second port of the second optical circulator 44 and wirelessly transmitted through the second optical signal transceiver antenna 43. The second optical signal transceiver antenna 43 can transmit the odd-channel signal in the terahertz link or the optical signal in the spatial laser link according to the link selection situation.In the first wireless transceiver module 3, in the terahertz link, the first terahertz signal transceiver antenna 32 receives the terahertz signal transmitted by the second terahertz signal transceiver antenna 41 in the second wireless transceiver module 4. This terahertz signal is input from the common port of the first orthomode transducer 31 and output from the vertical polarization port of the first orthomode transducer 31, then enters the first terahertz / spatial laser fiber wireless conversion module 2. The signal is amplified by the second low-noise amplifier 2b1. The first intensity modulator 2b2 and the first external cavity laser 2b3 modulate this terahertz signal onto an optical signal to form an optical bandpass signal. The signal power is amplified by the fourth erbium-doped fiber amplifier 2b4, and then an arbitrary sideband in the optical bandpass signal is filtered out by the first tunable optical filter 2b5 to obtain a single-sideband signal. This single-sideband signal enters the first optical signal transceiver module 1, passes through the link selection switch 13 at the Rx end of the first optical signal transceiver module 1, and then enters the first optical module SFP+11. The first optical module SFP+11 converts the optical signal into an electrical signal for further processing by the external main board. In the spatial laser link, the first optical signal transceiver antenna 34 receives the optical signal transmitted by the second optical signal transceiver antenna 43 in the second wireless transceiver module 4. This optical signal is input from the second port of the first optical circulator 33 and output from the third port of the first optical circulator 33, then enters the first terahertz / spatial laser fiber wireless conversion module 2. After the power is amplified by the fifth erbium-doped fiber amplifier 2b6, it enters the first optical signal transceiver module 1, passes through the link selection switch 13 at the Rx end of the first optical signal transceiver module 1, and then enters the first optical module SFP+11. The first optical module SFP+11 converts the optical signal into an electrical signal for further processing by the external main board.

[0085] It should be noted that the terms "first", "second", etc. in the description, claims and above-mentioned drawings of the present invention are used to distinguish similar objects and do not necessarily have to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0086] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this invention belongs. The terms used in the description of the present invention herein are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0087] It should be understood that the various forms of the processes shown above can be used, with steps reordered, added, or deleted. For example, the steps recited in the present invention can be executed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution of the present invention can be achieved, and the present invention is not limited herein.

[0088] The above specific embodiments do not constitute a limitation on the protection scope of the present invention. Those skilled in the art should understand that various modifications, combinations, sub - combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A full-duplex terahertz and spatial laser fusion transmission system, characterized in that It includes at least one set of sequentially connected optical signal transceiver modules, terahertz / space laser fiber wireless conversion modules, and wireless transceiver modules; among them, The optical signal transceiver module is used for selecting and switching between the terahertz link or the space laser link. Among them, in the transmitting link, it transmits an optical signal to the terahertz / space laser fiber wireless conversion module; in the receiving link, for the terahertz link, it receives the single-sideband signal from the terahertz / space laser fiber wireless conversion module, and for the space laser link, it receives the optical signal from the terahertz / space laser fiber wireless conversion module; The terahertz / space laser fiber wireless conversion module is used for receiving the optical signal transmitted from the optical signal transceiver module in the transmitting link; among them, For the terahertz link, it drives the optical signal through a radio frequency signal to generate a first-order sideband signal, forms an optical modulation signal, divides the optical modulation signal into two signals, namely an odd-channel signal and an even-channel signal, beats the even-channel signal to form a terahertz signal and amplifies the terahertz signal, amplifies the odd-channel signal, and transmits these two signals to the wireless transceiver module; these two signals refer to the amplified terahertz signal and the amplified odd-channel signal; For the space laser link, it amplifies the optical signal and then transmits it to the wireless transceiver module; It is used in the receiving link: For the terahertz link, it is used to modulate the terahertz signal input by the wireless transceiver module onto an optical carrier signal, form an optical bandpass signal, filter any one of the sidebands from the optical bandpass signal, form a single-sideband signal and transmit it to the optical signal transceiver module; For the space laser link, it amplifies the optical signal input by the wireless transceiver module and then transmits it to the optical signal transceiver module; The wireless transceiver module is used for wirelessly transmitting one terahertz signal and one optical signal from the terahertz / space laser fiber wireless conversion module in the transmitting link; among them, one terahertz signal refers to the amplified terahertz signal output by the terahertz / space laser fiber wireless conversion module, and one optical signal refers to the amplified odd-channel signal output by the terahertz / space laser fiber wireless conversion module or the optical signal output by the space laser link; In the receiving link, it wirelessly receives one terahertz signal and one optical signal input from the outside and sends them to the terahertz / space laser fiber wireless conversion module.

2. The full-duplex terahertz and spatial laser fusion transmission system according to claim 1, wherein The optical signal transceiver module includes an optical module SFP+ and a link selection switch; among them, The link selection switch is used for selecting and switching between the terahertz link or the space laser link; The optical module SFP+ is used for converting the electrical signal from the external main board into an optical signal and transmitting the optical signal to the terahertz / space laser fiber wireless conversion module through the optical fiber in the transmitting link; in the receiving link, for the terahertz link, it receives the single-sideband signal from the terahertz / space laser fiber wireless conversion module through the optical fiber, and for the space laser link, it receives the optical signal from the terahertz / space laser fiber wireless conversion module through the optical fiber; and converts the single-sideband signal or the optical signal into an electrical signal for further processing by the external main board.

3. A full-duplex terahertz and spatial laser fusion transmission system according to claim 1, characterized in that, The terahertz / spatial laser fiber wireless conversion module includes a first erbium-doped fiber amplifier, a phase modulator, an electro-absorption modulator, an interleaver filter, a second erbium-doped fiber amplifier, a photodetector, a first low-noise amplifier, an optical coupler, a third erbium-doped fiber amplifier, a second low-noise amplifier, an intensity modulator, an external cavity laser, a fourth erbium-doped fiber amplifier, a tunable optical filter, and a fifth erbium-doped fiber amplifier; wherein, In the transmitting link, The first erbium-doped fiber amplifier is used to amplify the optical signal to be transmitted in the terahertz link; The electro-absorption modulator and the phase modulator are used to drive the amplified optical signal to be transmitted to generate a first-order sideband signal, forming an optical modulation signal; The interleaver filter is used to separate the optical modulation signal into odd channels and even channels, obtaining an odd-channel signal and an even-channel signal; wherein, the odd-channel signal is the baseband signal in the optical modulation signal, and the even-channel signal is the two first-order sideband signals in the optical modulation signal; The second erbium-doped fiber amplifier is used to amplify the even-channel signal; The photodetector is used to perform beat frequency processing on the amplified even-channel signal to generate a terahertz signal; The first low-noise amplifier is used to amplify the terahertz signal; The optical coupler is used to transmit the odd-channel signal in the terahertz link and the optical signal in the spatial laser link to the same optical fiber; The third erbium-doped fiber amplifier is used to amplify the odd-channel signal in the terahertz link or the optical signal in the spatial laser link in the optical fiber; In the receiving link, The second low-noise amplifier is used to amplify the terahertz signal input by the wireless transceiver module in the terahertz link; The intensity modulator and the external cavity laser are used to modulate the amplified terahertz signal onto the optical carrier signal to form an optical bandpass signal; The fourth erbium-doped fiber amplifier is used to amplify the optical bandpass signal; The tunable optical filter is used to filter out any one of the sidebands of the amplified optical bandpass signal to obtain a single-sideband signal; The fifth erbium-doped fiber amplifier is used to amplify the optical signal input from the wireless transceiver module in the spatial laser link.

4. The full-duplex terahertz and spatial laser fusion transmission system according to claim 1, wherein The wireless transceiver module includes an orthomode transducer, an optical circulator, a terahertz signal transceiver antenna, and an optical signal transceiver antenna; wherein, The orthomode transducer is used to, in the transmitting link, receive the amplified terahertz signal output from the terahertz / spatial laser fiber wireless conversion module and output the amplified terahertz signal to the terahertz transceiver antenna for transmission; in the receiving link, receive the terahertz signal transmitted by the terahertz signal transceiver antenna and output it to the terahertz / spatial laser fiber wireless conversion module; The optical circulator is used to, in the transmitting link, receive the amplified odd-channel signal output from the terahertz / spatial laser fiber wireless conversion module or the optical signal output from the spatial laser link and output the amplified odd-channel signal or the optical signal output from the spatial laser link to the optical signal transceiver antenna; in the receiving link, receive the optical signal transmitted by the optical signal transceiver antenna and output the optical signal to the terahertz / spatial laser fiber wireless conversion module; A terahertz signal transceiver antenna is used to wirelessly transmit the amplified terahertz signal output from the terahertz / spatial laser fiber wireless conversion module in the transmit link; in the receive link, it is used to wirelessly receive the externally input terahertz signal and send it to the terahertz / spatial laser fiber wireless conversion module. An optical signal transceiver antenna is used to wirelessly transmit the amplified odd-channel signal output from the terahertz / spatial laser fiber wireless conversion module or the optical signal output from the spatial laser link in the transmit link; in the receive link, it is used to wirelessly receive the externally input optical signal and send it to the terahertz / spatial laser fiber wireless conversion module.

5. A full-duplex terahertz and spatial laser fusion transmission system according to claim 4, wherein, The two-mode orthogonal terahertz signals in the transmit link and the receive link are combined into one signal via an orthogonal mode converter, and mode separation is generated to realize the transmission and reception of terahertz signals using only one antenna; the two optical signals in the transmit link and the receive link pass through an optical circulator to realize the separation and unidirectional transmission of the uplink and downlink optical signals, and realize the transmission and reception of optical signals using only one antenna.

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