Broadband microwave photon transceiving delay module and large-scale light-operated phased array system

Abstract

The invention discloses a broadband microwave photon transceiving delay module and a large-scale light-operated phased array system, and the module comprises a thin-film lithium niobate modulation delay chip, and a laser and a high-speed detector chip which are integrated on the thin-film lithium niobate modulation delay chip in a heterogeneous manner. The thin-film lithium niobate modulation time-delay chip comprises a thin-film lithium niobate single chip, an electro-optical modulator and a bidirectional numerical control optical true time-delay unit, wherein the electro-optical modulator and the bidirectional numerical control optical true time-delay unit are integrated on the thin-film lithium niobate single chip; and the bidirectional numerical control optical true time-delay unit is used for adjusting time delay of an optical path according to requirements. In the broadband microwave photon transceiving delay module, monolithic integration of electro-optical modulation and optical delay functions is realized by adopting the film lithium niobate monolithic, the integration level of the broadband microwave photon transceiving delay module is improved, and miniaturization and light weight of the broadband microwave photon transceiving delay module are realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of microwave photons, and in particular relates to a broadband microwave photon transceiver delay module and a large-scale optically controlled phased array system. Background Art

[0002] Microwave photonic technology can realize the transmission and processing of microwave signals in the optical domain. It has the advantages of high working frequency band, large instantaneous bandwidth, low delay loss, strong parallel processing capability, and can be integrated. It has broad application prospects in radar, communication, electronic countermeasures, measurement and control, etc. However, conventional microwave optical transceiver delay functional units are composed of discrete lasers, electro-optical modulators, photodetectors, and optical delay devices. They have problems such as large size, heavy weight, and poor reliability, which seriously limit the array scale and beam performance of optical phased array systems and cannot meet the application requirements of the new generation of broadband and multi-functional phased array systems. Summary of the invention

[0003] In view of the above-mentioned deficiencies in the prior art, the technical problem to be solved by the present invention is to provide a broadband microwave photon transceiver delay module and a large-scale optically controlled phased array system.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0005] A broadband microwave photon transceiver delay module comprises a thin film lithium niobate modulation delay chip and a laser and a high-speed detector chip heterogeneously integrated on the thin film lithium niobate modulation delay chip, wherein the thin film lithium niobate modulation delay chip comprises a thin film lithium niobate single chip and an electro-optic modulator and a bidirectional digitally controlled optical true delay unit integrated on the thin film lithium niobate single chip, wherein the first end of the electro-optic modulator is connected to the output end of the laser; the bidirectional digitally controlled optical true delay unit is used to adjust the delay of the optical path according to demand, and the first end of the bidirectional digitally controlled optical true delay unit has a first input interface and a second output interface; the first input interface of the bidirectional digitally controlled optical true delay unit is connected to the second end of the electro-optic modulator, and the second output interface of the bidirectional digitally controlled optical true delay unit is connected to the input end of the detector chip; the second end of the bidirectional digitally controlled optical true delay unit has a second input interface and a first output interface, and the second input interface and the first output interface of the bidirectional digitally controlled optical true delay unit are used to interconnect with external devices.

[0006] Furthermore, the first end of the electro-optic modulator is connected to the output end of the laser through a first optical waveguide unit etched on a thin-film lithium niobate monolithic chip, the first input interface of the bidirectional digitally controlled optical true delay unit is connected to the second end of the electro-optic modulator through a second optical waveguide unit etched on a thin-film lithium niobate monolithic chip, and the second output interface of the bidirectional digitally controlled optical true delay unit is connected to the input end of the detector chip through a third optical waveguide unit etched on a thin-film lithium niobate monolithic chip.

[0007] Furthermore, the first optical waveguide unit includes a first "Y" branch waveguide and a first connecting waveguide, the combined end of the first "Y" branch waveguide is connected to the first end of the electro-optical modulator, the first branch end of the first "Y" branch waveguide is connected to the first end of the first connecting waveguide, and the second end of the first connecting waveguide is connected to the output end of the laser as the first input end of the thin film lithium niobate modulation delay chip; the second optical waveguide unit includes a second connecting waveguide, and the first input interface of the bidirectional digitally controlled optical true delay unit is connected to the second end of the electro-optical modulator through the second connecting waveguide; the third optical waveguide unit includes a third connecting waveguide, the second output interface of the bidirectional digitally controlled optical true delay unit is connected to the first end of the third connecting waveguide, and the second end of the third connecting waveguide is used as the second output end of the thin film lithium niobate modulation delay chip.

[0008] Furthermore, the output end of the laser and the first input end of the thin-film lithium niobate modulation delay chip are coupled by light beam collimation through a lens isolator using a spatial optical path design.

[0009] Furthermore, the high-speed detector chip adopts a back-illuminated structure, and the input end of the high-speed detector chip is coupled with the second output end of the thin-film lithium niobate modulation delay chip through a waveguide grating.

[0010] Furthermore, the electro-optic modulator adopts a push-pull structure and a traveling wave electrode structure.

[0011] Furthermore, the bidirectional digitally controlled optical true delay unit comprises N cascade-connected optical switches and (N-1) delay components respectively connected between two adjacent optical switches, and the thin-film lithium niobate monolithic chip is further etched with a fourth connecting waveguide and a fifth connecting waveguide; the optical switch is based on MZ I interference structure of 2x2 optical switch; the first end of the first-stage optical switch is used as the first input interface of the first end of the bidirectional digitally controlled optical true delay unit, and the second end of the first-stage optical switch is used as the second output interface of the first end of the bidirectional digitally controlled optical true delay unit; the third end of the first-stage optical switch to the (N-1)-stage optical switch is respectively connected to the first end of the next-stage optical switch through a first arm, and each of the first arms is respectively provided with a delay component, thereby forming a delay arm; the fourth end of the first-stage optical switch to the (N-1)-stage optical switch is respectively connected to the second end of the next-stage optical switch through a second arm, and each of the second arms is a straight waveguide, thereby forming a reference arm; the third end of the N-stage optical switch is connected to the first end of the fourth connecting waveguide, and the second end of the fourth connecting waveguide is used as the first output interface of the bidirectional digitally controlled optical true delay unit, and the fourth end of the N-stage optical switch is connected to the first end of the fifth connecting waveguide, and the second end of the fifth connecting waveguide is used as the second input interface of the bidirectional digitally controlled optical true delay unit.

[0012] Furthermore, the delay component is an optical waveguide delay line formed on the first arm.

[0013] Furthermore, each of the first arms and each of the second arms is connected to an optical power monitoring detector, and the optical signal power ratio R of the first arm and the second arm at the corresponding position is 1 The calculation formula is:

[0014]

[0015] In the formula, I mpd1 Represents the output photocurrent of the optical power monitoring detector connected to the delay arm; I mpd2 represents the output photocurrent of the optical power monitoring detector connected to the reference arm; γ 1 represents the power ratio of the delay arm to the monitoring detector connected to it, γ 2 represents the power ratio distributed from the reference arm to the monitoring detector connected to it; Indicates the responsiveness of the optical power monitoring detector connected to the delay arm, Represents the responsivity of the optical power monitoring detector connected to the reference arm; P d Represents the optical power of the delay arm; P r Represents the optical power of the reference arm.

[0016] A large-scale optically controlled phased array system includes a plurality of broadband microwave photon transceiver delay modules.

[0017] In the present invention, a thin-film lithium niobate monolithic chip is used to realize the monolithic integration of electro-optic modulation and optical delay functions, and heterogeneous integration is used to realize the integrated packaging of thin-film lithium niobate modulation delay chip and laser and high-speed detector chip, realizing the de-fiberization design of the optical interconnection part, improving the integration of broadband microwave photon transceiver delay module, and realizing the miniaturization and lightweight of broadband microwave photon transceiver delay module. The use of a thin-film lithium niobate monolithic chip with strong electro-optical effect can improve the broadband high-efficiency capability of the electro-optic modulator and realize the high-speed and low-energy switching capability of optical delay; the use of heterogeneous optoelectronic multi-chip integration is helpful to realize the high performance and high reliability of microwave optical transceiver, and the use of lithium niobate optical waveguide to form an optical switch greatly improves the switching speed and can realize a higher switch extinction ratio. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0019] Figure 1 It is a schematic structural diagram of an embodiment of a broadband microwave photon transceiver delay module of the present invention.

[0020] Figure 2 This is the structural block diagram of the broadband microwave photon transceiver delay module;

[0021] Figure 3 This is a schematic diagram of the layout of the broadband microwave photonic transceiver delay module.

[0022] Figure 4 Schematic diagram of the structure of the electro-optic modulator.

[0023] Figure 5 A schematic diagram of a structure for monitoring the optical power on the first arm and the second arm.

[0024] Figure 6 The figure is a schematic diagram of the layout of a broadband microwave photonic transceiver delay module in a specific example.

[0025] Figure 7 It is a schematic structural diagram of an embodiment of a large-scale optically controlled phased array system of the present invention.

[0026] The accompanying drawings in the specification are numeraled as follows:

[0027] Thin-film lithium niobate modulation delay chip-100; thin-film lithium niobate monolithic chip-110; first "Y" branch waveguide-121; second "Y" branch waveguide-122; first connecting waveguide-131; second connecting waveguide-132; third connecting waveguide-133; fourth connecting waveguide-134; fifth connecting waveguide-135;

[0028] Electro-optic modulator-200; interferometer arm-210; radio frequency electrode-220; ground electrode-230;

[0029] Bidirectional digital controlled optical true delay unit-300; first arm-310; delay unit-311, S 1 , S 2 , S 3 , S 4 , S 5 , S 6 , S 7 , S 8 , S N-1 ; Second arm-320; Optical switch-330, K 1 , K 2 , K 3 , K 4 , K 5 , K 6 , K 7 , K 8 , K 9 , K N-1 , K N ;

[0030] Laser-400; Lens isolator-500; High-speed detector chip-600; Optical power monitoring detector-700; Polarization-maintaining fiber-800;

[0031] Broadband microwave photon transceiver delay module-910; integrated signal processing system-920; beam synthesis module-930; excitation signal module-940; array antenna-950. DETAILED DESCRIPTION

[0032] The following describes the implementation methods of the present invention through specific examples. The illustrations provided in the following embodiments are only used to schematically illustrate the basic concept of the present invention. The following embodiments and features in the embodiments may be combined with each other without conflict.

[0033] See also Figure 1 , Figure 1 The schematic diagram of the structure of an embodiment of a broadband microwave photon transceiver delay module of the present invention. The broadband microwave photon transceiver delay module of this embodiment includes a thin-film lithium niobate modulation delay chip 100 and a laser 400 and a high-speed detector chip 600 heterogeneously integrated on the thin-film lithium niobate modulation delay chip 100. The laser 400 generally adopts a low-noise high-power laser source.

[0034] See also Figure 2 and Figure 3The thin-film lithium niobate modulation delay chip 100 includes a thin-film lithium niobate monolithic chip 110 and an electro-optic modulator 200 and a bidirectional digitally controlled optical true delay unit 300 integrated on the thin-film lithium niobate monolithic chip 110. The thin-film lithium niobate monolithic chip 110 with strong electro-optical effect integrates the electro-optic modulation function and the optical delay function. On the one hand, the broadband high-efficiency capability of the electro-optic modulator 200 can be improved, and on the other hand, the high-speed and low-energy switching capability of the optical delay can be realized. The use of a heterogeneous method for optoelectronic multi-chip integration is conducive to achieving high performance and high reliability of microwave optical transceiver. The first end of the electro-optic modulator 200 is connected to the output end of the laser 400; in order to adopt a fiber-free design in the optical interconnection part, the first end of the electro-optic modulator 200 can be connected to the output end of the laser 400 through a first optical waveguide unit etched on the thin-film lithium niobate monolithic chip 110. Specifically, the first optical waveguide unit includes a first "Y" branch waveguide 121 and a first connecting waveguide 131. The combined end of the first "Y" branch waveguide 121 is connected to the first end of the electro-optic modulator 200, the first branch end of the first "Y" branch waveguide 121 is connected to the first end of the first connecting waveguide 131, and the second end of the first connecting waveguide 131 serves as the first input end of the thin-film lithium niobate modulation delay chip 100. In this embodiment, the output end of the laser 400 and the first input end of the thin-film lithium niobate modulation delay chip 100 are coupled by light beam collimation through a lens isolator 500 using a spatial optical path design. The second branch end of the first "Y" branch waveguide 121 is used to monitor the output state of the electro-optic modulator 200.

[0035] See also Figure 4 The electro-optic modulator 200 includes two interference arms 210, a radio frequency electrode 220 is arranged between the two interference arms 210, and a ground electrode 230 is respectively arranged on the outer sides of the two interference arms 210, thereby forming a push-pull structure. The radio frequency electrode 220 and the two ground electrodes 230 are arranged in parallel with the interference arms 210, so that the direction of the radio frequency signal in the radio frequency electrode 220 is consistent with the direction of the optical signal in the interference arm 210, so that the optical signal is modulated while being transmitted during the transmission process, forming a traveling wave electrode structure. The electro-optical modulation functional unit adopts a push-pull structure to improve the modulation efficiency, and the use of a traveling wave electrode can improve the modulation bandwidth.

[0036] Please continue reading Figure 2 and Figure 3The bidirectional digitally controlled optical true delay unit 300 is used to adjust the delay of the optical path according to the demand. The first end of the bidirectional digitally controlled optical true delay unit 300 has a first input interface and a second output interface. The first input interface of the bidirectional digitally controlled optical true delay unit 300 is connected to the second end of the electro-optical modulator 200, and the second output interface of the bidirectional digitally controlled optical true delay unit 300 is connected to the input end of the detector chip. The second end of the bidirectional digitally controlled optical true delay unit 300 has a second input interface and a first output interface. The second input interface and the first output interface of the bidirectional digitally controlled optical true delay unit 300 are used to interconnect with external devices.

[0037] The first input interface of the bidirectional digitally controlled optical true delay unit 300 is connected to the second end of the electro-optic modulator 200 through the second optical waveguide unit etched on the thin-film lithium niobate monolithic chip 110; specifically, the second optical waveguide unit includes a second "Y" branch waveguide 122 and a second connecting waveguide 132. The combined end of the second "Y" branch waveguide 122 is connected to the second end of the electro-optic modulator 200, the first branch end of the second "Y" branch waveguide 122 is connected to the first end of the second connecting waveguide 132, the second branch end of the second "Y" branch waveguide 122 is suspended, and the second end of the second connecting waveguide 132 is connected to the first input interface of the bidirectional digitally controlled optical true delay unit 300. Of course, the second "Y" branch waveguide 122 can also be removed, so that the first input interface of the bidirectional digitally controlled optical true delay unit 300 is directly connected to the second end of the electro-optic modulator 200 through the second connecting waveguide 132.

[0038] The second output interface of the bidirectional digitally controlled optical true delay unit 300 is connected to the input end of the detector chip through the third optical waveguide unit etched on the thin film lithium niobate monolithic chip 110. In this embodiment, the third optical waveguide unit is defined as the third connecting waveguide 133, the second output interface of the bidirectional digitally controlled optical true delay unit 300 is connected to the first end of the third connecting waveguide 133, and the second end of the third connecting waveguide 133 serves as the second output end of the thin film lithium niobate modulation delay chip 100. The high-speed detector chip 600 adopts a back-illuminated structure, and the input end of the high-speed detector chip 600 is coupled to the second output end of the thin film lithium niobate modulation delay chip 100 through a waveguide grating.

[0039] The second input interface and the first output interface of the bidirectional digitally controlled optical true delay unit 300 are respectively used as the second input end and the first output end of the thin film lithium niobate modulation delay chip 100, and the second input end and the first output end of the thin film lithium niobate modulation delay chip 100 are used as the external interconnection interface of the broadband microwave photon transceiver delay module, and polarization-maintaining optical fiber is used for coupling and interconnection. The bottom of the thin film lithium niobate modulation delay chip 100 can also use a TEC temperature control module to improve the working stability of the module under high and low temperature conditions.

[0040] Please continue reading Figure 2 The bidirectional digitally controlled optical true delay unit 300 includes N cascade-connected optical switches 330 (in this embodiment, optical switches K 1 , Optical switch K 2 , Optical switch K 3 , Optical switch K 4 , Optical switch K 5 , ..., optical switch K N-1 , Optical switch K N ) and (N-1) delay components 311 (delay units S in this embodiment) respectively connected between two adjacent optical switches 1 , Delay unit S 2 , Delay unit S 3 , Delay unit S 4 , ..., delay unit S N-1 ), the optical switch is a 2x2 optical switch (i.e., 2x2 OSW) based on an MZ I interference structure. The waveguide formed on the thin-film lithium niobate monolithic chip 110 is used to realize the switching function. On the one hand, the switching speed can be increased by more than three orders of magnitude to the ns or even ps level by utilizing its electro-optical effect, and the thin-film lithium niobate waveguide has extremely low absorption loss, so a high switching extinction ratio can be achieved.

[0041] The first end of the first optical switch 330 serves as the first input interface of the first end of the bidirectional digitally controlled optical true delay unit 300, and the second end of the first optical switch 330 serves as the second output interface of the first end of the bidirectional digitally controlled optical true delay unit 300. The third ends of the first optical switch 330 to the (N-1)th optical switch 330 are respectively connected to the first end of the next optical switch 330 through a first arm 310, and each of the first arms 310 is respectively provided with a delay component 311, thereby forming a delay arm; in this embodiment, the delay component 311 is an optical waveguide delay line formed on the first arm 310. The fourth ends of the first optical switch 330 to the (N-1)th optical switch 330 are respectively connected to the second end of the next optical switch 330 through a second arm 320, and each of the second arms 320 is a straight waveguide, thereby forming a reference arm. The third end of the optical switch 330 of the Nth stage is connected to the first end of the fourth connecting waveguide 134, and the second end of the fourth connecting waveguide 134 serves as the first output interface of the bidirectional digitally controlled optical true delay unit 300. The fourth connecting waveguide 134 and the fifth connecting waveguide 135 are also etched on the thin-film lithium niobate monolithic chip 110; the fourth end of the optical switch 330 of the Nth stage is connected to the first end of the fifth connecting waveguide 135, and the second end of the fifth connecting waveguide 135 serves as the second input interface of the bidirectional digitally controlled optical true delay unit 300.

[0042] The delay of the bidirectional digital controlled optical true delay unit 300 needs to be finally determined according to the signal frequency, array size and scanning angle. The delay of the lithium niobate optical waveguide can be expressed as:

[0043]

[0044] Where N 0 is the effective refractive index of lithium niobate optical waveguide; ΔL is the delay difference between the delay arm and the reference arm; c represents the speed of light.

[0045] The delay time of the (N-1) delay components 311 can be set in binary mode. That is, when the required basic delay time unit is Δτ, the delay time of the (N-1) delay components 311 is Δτ, 2Δτ, 2 2 Δτ, ..., 2 N-1 Δτ; thus, the delay time can be controlled by the optical switch 330 in Δτ~(2 N -1)Δτ can take any integer multiple of Δτ. The (N-1) delay components 311 can be arranged in order from small to large delay time between the N-level optical switches 330 for easy control. Of course, the (N-1) delay components 311 can also be arranged in other orders or randomly arranged between the N-level optical switches 330.

[0046] See also Figure 5When a 9-bit 18 GHz broadband microwave photon transceiver delay module is to be implemented, the bidirectional digitally controlled optical true delay unit 300 includes an optical switch K 1 , Optical switch K 2 , Optical switch K 3 , Optical switch K 4 , Optical switch K 5 , Optical switch K 6 , Optical switch K 7 , Optical switch K 8 , Optical switch K 9 A total of 9 cascade-connected optical switches 330 and delay components S 1 , Delay component S 2 , Delay component S 3 , Delay component S 4 , Delay component S 5 , Delay component S 6 , Delay component S 7 , Delay component S 8 There are 8 delay components 311 in total. At this time, the delay times of the 8 delay components 311 are Δτ, 2Δτ, and 4Δτ respectively (i.e., 2 2 Δτ), 8Δτ (i.e. 2 3 Δτ), 16Δτ (i.e. 2 4 Δτ), 32Δτ (i.e. 2 5 Δτ), 64Δτ (i.e. 2 6 Δτ), 128Δτ (i.e. 2 7 Δτ), 256Δτ (i.e. 2 9-1 Δτ), so that in Δτ~(2 9 -1)Δτ (i.e., 511Δτ) can take any integer multiple of Δτ.

[0047] Since the 2x2 optical switch based on the MZI interference structure formed by the thin-film lithium niobate waveguide is greatly affected by temperature, in order to solve the degradation of the switch performance caused by the temperature drift caused by the pyroelectric effect of the lithium niobate waveguide, this embodiment adopts a method of monitoring the optical power on the first arm 310 and the second arm 320 to adjust the state of the optical switch 330 in real time, thereby eliminating the influence of the temperature drift caused by the pyroelectric effect on the optical switch 330, so that the optical switch 330 remains in the through state (that is, the optical signal in the first arm 310 of the previous stage is transmitted to the first arm 310 of the next stage, and the optical signal in the second arm 320 of the previous stage is transmitted to the second arm 320 of the next stage) or the cross state (that is, the optical signal in the first arm 310 of the previous stage is transmitted to the second arm 320 of the next stage, and the optical signal in the second arm 320 of the previous stage is transmitted to the first arm 310 of the next stage).

[0048] See also Figure 3 , Figure 5 and Figure 6 In this embodiment, an optical power monitoring detector 700 (i.e., MPD) is connected to each of the first arms 310 and each of the second arms 320, and the optical power monitoring detector 700 can be installed and fixed by using a surface mounting process. Of course, in order to monitor the optical signal more comprehensively, in this embodiment, an optical power monitoring detector 700 is also connected to the second connecting waveguide 132, the fourth connecting waveguide 134, and the fifth connecting waveguide 135. The optical power monitoring detector 700 can simultaneously monitor the light-passing state of the reference arm and the delay arm, that is, a small part of the light is separated from the reference arm and the delay arm and sent to the surface mounted optical power monitoring detector 700 for detection, and the optical signal is converted into an electrical signal. By adjusting the optical power ratio of the two signals in real time, the optical switch 330 can be stably operated in a straight-through state or a cross state.

[0049] The optical signal power ratio R of the first arm 310 and the second arm 320 at the corresponding position 1 The calculation formula is:

[0050]

[0051] In the formula, I mpd1 I represents the output photocurrent of the optical power monitoring detector 700 connected to the delay arm; mpd2 represents the output photocurrent of the optical power monitoring detector 700 connected to the reference arm; γ 1 represents the power ratio of the delay arm to the monitoring detector connected to it, γ 2 represents the power ratio distributed from the reference arm to the monitoring detector connected to it; represents the responsiveness of the optical power monitoring detector 700 connected to the delay arm, represents the responsivity of the optical power monitoring detector 700 connected to the reference arm; P d Represents the optical power of the delay arm; P r Represents the optical power of the reference arm. 1 After the value of R 1 The value of determines whether the optical switch 330 is working in the through state or the cross state. 1 When it deviates from the maximum value or the minimum value, the driving voltage of the optical switch 330 can be adjusted in real time according to the value of R1, thereby adjusting the optical power ratio of the two signals of the first arm 310 and the second arm 320, so that R 1 The value of is maintained at the maximum or minimum value, that is, the optical switch 330 is maintained in the required state, eliminating the influence of temperature drift caused by the pyroelectric effect on the optical switch 330.

[0052] This embodiment proposes a broadband microwave photon transceiver delay module based on hybrid integration: wherein, a thin-film lithium niobate monolithic chip 110 is used to realize the monolithic integration of electro-optical modulation and optical delay functions; heterogeneous integration is used to realize the integrated packaging of the thin-film lithium niobate modulation delay chip 100, the laser 400, and the high-speed detector chip 600, realizing the de-fiberization design of the optical interconnection part, improving the integration of the broadband microwave photon transceiver delay module, and realizing the miniaturization and lightness of the broadband microwave photon transceiver delay module. In this embodiment, the thin-film lithium niobate monolithic chip 110 with strong electro-optical effect is used to integrate the electro-optical modulation function and the optical delay function, which can improve the broadband high-efficiency capability of the electro-optical modulator 200 on the one hand, and realize the high-speed and low-energy switching capability of the optical delay on the other hand; the heterogeneous method is used to carry out optoelectronic multi-chip integration, which is helpful to realize the high performance and high reliability of microwave optical transceiver, and the lithium niobate optical waveguide is used to form the optical switch 330, which greatly improves the switching speed and can achieve a higher switching extinction ratio.

[0053] See also Figure 7 , Figure 7 This is a schematic diagram of the structure of an embodiment of a large-scale optically controlled phased array system of the present invention. The large-scale optically controlled phased array system of this embodiment includes a plurality of broadband microwave photon transceiver delay modules 910 as described in any of the above embodiments. Of course, the large-scale optically controlled phased array system also includes other structures necessary for the phased array system, such as an integrated signal processing system 920, a beamforming module 930, an excitation signal module 940, and an array antenna 950. These are all current technologies and will not be described in detail here.

[0054] The working principle of the large-scale optically controlled phased array system of this embodiment is as follows:

[0055] See also Figures 1 to 7 The laser 400 of the broadband microwave photon transceiver delay module 910 provides an optical carrier to be injected into the electro-optical modulator 200 to complete the electro-optical conversion of the microwave downlink signal. The modulated optically-carried microwave signal passes through the multi-bit CNC bidirectional CNC optical true delay unit 300 to complete a specific signal delay, and then is output to the back end for beam synthesis and other processing; after the uplink optically-carried microwave signal enters the broadband microwave photon transceiver delay module 910, it first completes the optical delay function, and then is input into the photoelectric detector and restored to a microwave signal through photoelectric demodulation, and finally is sent to the array antenna for transmission.

[0056] This embodiment solves the problem of insufficient array integration capability of the core receiving and transmitting delay function of the optically controlled phased array system, reduces the volume and weight of the optically controlled phased array system, improves the reliability of the optically controlled phased array system, and can be widely used in the unit level or sub-array level of a broadband phased array system.

[0057] The above embodiments only express the preferred implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A broadband microwave photon transceiver delay module, characterized in that: It includes a thin-film lithium niobate modulation delay chip and a laser and a high-speed detector chip heterogeneously integrated on the thin-film lithium niobate modulation delay chip. The thin-film lithium niobate modulation delay chip includes a thin-film lithium niobate single chip and an electro-optical modulator and a bidirectional digitally controlled optical true delay unit integrated on the thin-film lithium niobate single chip. The first end of the electro-optical modulator is connected to the output end of the laser; the bidirectional digitally controlled optical true delay unit is used to adjust the delay of the optical path according to demand, and the first end of the bidirectional digitally controlled optical true delay unit has a first input interface and a second output interface; the first input interface of the bidirectional digitally controlled optical true delay unit is connected to the second end of the electro-optical modulator, and the second output interface of the bidirectional digitally controlled optical true delay unit is connected to the input end of the detector chip; the second end of the bidirectional digitally controlled optical true delay unit has a second input interface and a first output interface, and the second input interface and the first output interface of the bidirectional digitally controlled optical true delay unit are used to interconnect with external devices.

2. The broadband microwave photon transceiver delay module according to claim 1, characterized in that: The first end of the electro-optic modulator is connected to the output end of the laser through a first optical waveguide unit etched on a thin-film lithium niobate monolithic chip, the first input interface of the bidirectional digitally controlled optical true delay unit is connected to the second end of the electro-optic modulator through a second optical waveguide unit etched on a thin-film lithium niobate monolithic chip, and the second output interface of the bidirectional digitally controlled optical true delay unit is connected to the input end of the detector chip through a third optical waveguide unit etched on a thin-film lithium niobate monolithic chip.

3. The broadband microwave photon transceiver delay module according to claim 2, characterized in that: The first optical waveguide unit includes a first "Y" branch waveguide and a first connecting waveguide, the combined end of the first "Y" branch waveguide is connected to the first end of the electro-optical modulator, the first branch end of the first "Y" branch waveguide is connected to the first end of the first connecting waveguide, and the second end of the first connecting waveguide is connected to the output end of the laser as the first input end of the thin film lithium niobate modulation delay chip; the second optical waveguide unit includes a second connecting waveguide, and the first input interface of the bidirectional digitally controlled optical true delay unit is connected to the second end of the electro-optical modulator through the second connecting waveguide; the third optical waveguide unit includes a third connecting waveguide, the second output interface of the bidirectional digitally controlled optical true delay unit is connected to the first end of the third connecting waveguide, and the second end of the third connecting waveguide is used as the second output end of the thin film lithium niobate modulation delay chip.

4. The broadband microwave photon transceiver delay module according to claim 3, characterized in that: The output end of the laser and the first input end of the thin-film lithium niobate modulation delay chip are coupled by light beam collimation through a lens isolator using a spatial optical path design.

5. The broadband microwave photon transceiver delay module according to claim 3, characterized in that: The high-speed detector chip adopts a back-illuminated structure, and the input end of the high-speed detector chip is coupled with the second output end of the thin-film lithium niobate modulation delay chip through a waveguide grating.

6. The broadband microwave photon transceiver delay module according to claim 1, characterized in that: The electro-optic modulator adopts a push-pull structure and a traveling wave electrode structure.

7. The broadband microwave photon transceiver delay module according to any one of claims 1 to 6, characterized in that: The bidirectional digitally controlled optical true delay unit comprises N cascade-connected optical switches and (N-1) delay components respectively connected between two adjacent optical switches; a fourth connecting waveguide and a fifth connecting waveguide are also etched on the thin-film lithium niobate monolithic chip; the optical switch is a 2x2 optical switch based on an MZI interference structure; the first end of the first-stage optical switch serves as a first input interface of the first end of the bidirectional digitally controlled optical true delay unit, and the second end of the first-stage optical switch serves as a second output interface of the first end of the bidirectional digitally controlled optical true delay unit; the third ends of the first-stage optical switch to the (N-1)-stage optical switch are respectively connected to the first end of the next-stage optical switch through a first arm, and each of the first arms is respectively provided with a delay component, thereby forming a delay arm; The fourth ends of the first-stage optical switch to the (N-1)-stage optical switch are respectively connected to the second end of the next-stage optical switch through a second arm, and each of the second arms is a straight waveguide, thereby forming a reference arm; the third end of the N-stage optical switch is connected to the first end of the fourth connecting waveguide, and the second end of the fourth connecting waveguide serves as the first output interface of the bidirectional digitally controlled optical true delay unit; the fourth end of the N-stage optical switch is connected to the first end of the fifth connecting waveguide, and the second end of the fifth connecting waveguide serves as the second input interface of the bidirectional digitally controlled optical true delay unit.

8. The broadband microwave photon transceiver delay module according to claim 7, characterized in that: The delay component is an optical waveguide delay line formed on the first arm.

9. The broadband microwave photon transceiver delay module according to claim 7, characterized in that: Each of the first arms and each of the second arms is connected to an optical power monitoring detector, and the calculation formula for the optical signal power ratio R1 of the first arm and the second arm at the corresponding position is: In the formula, I mpd1 Represents the output photocurrent of the optical power monitoring detector connected to the delay arm; I mpd2 represents the output photocurrent of the optical power monitoring detector connected to the reference arm; γ1 represents the power ratio of the delay arm to the monitoring detector connected to it, and γ2 represents the power ratio of the reference arm to the monitoring detector connected to it; Indicates the responsiveness of the optical power monitoring detector connected to the delay arm, Represents the responsivity of the optical power monitoring detector connected to the reference arm; P d Represents the optical power of the delay arm; P r Represents the optical power of the reference arm.

10. A large-scale optically controlled phased array system, characterized in that: It comprises a plurality of broadband microwave photon transceiver delay modules as claimed in any one of claims 1 to 9.

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