A radar array device and method based on on-chip antenna-pulse source integration

Abstract

The present invention discloses a radar array device and method based on on-chip antenna-pulse source integration, which relates to the field of antenna technology, including an excitation structure, which is composed of a photoconductive switch and generates a high-frequency pulse current through laser excitation for exciting the array antenna; a transmission structure, which uses a low-loss GSG coplanar waveguide to transmit the high-frequency current to the array antenna for low-loss transmission; an acquisition structure, which is composed of a photoconductive switch and receives electromagnetic signals from the array antenna and converts them into current signals for signal acquisition and transmission; a radiation structure, which is composed of an array passive antenna and is used for mutual conversion between electromagnetic waves and current; the present application can effectively excite and collect electromagnetic waves, and the bandwidth can be extended to millimeter waves or even higher frequency bands, and has the characteristics of higher signal-to-noise ratio, lower power consumption and smaller size compared with the existing technology; it improves the receiving sensitivity and transmission efficiency of electromagnetic signals and reduces transmission loss.

Description

Technical Field

[0001] The present invention relates to the field of antenna technology, and in particular to a radar array device and method based on on-chip antenna-pulse source integration. Background Art

[0002] Antennas, as classic passive devices, can convert high-frequency alternating current into electromagnetic waves radiated from space and vice versa, and have been widely used in various fields. With the advent of the big data era, the demand for high-speed data transmission is increasing, and the frequency bands of wireless communications are gradually increasing. Currently, mature passive antenna designs exist in the industry, supporting millimeter-wave passive antenna designs. However, due to leakage effects caused by miniaturization, the operating frequency of electrical pulse sources is limited to below 110 GHz. Continuously multiplying low-frequency signals significantly attenuates the excitation power, making it impossible to meet practical requirements. Without the support of high-frequency pulse sources, high-frequency passive antennas are like castles in the air, further restricting the development of high-frequency wireless communications. Consequently, new high-frequency electromagnetic wave transmitting devices, such as photoconductive antennas, spin terahertz devices, and photodiode antennas, have been widely researched. Compared to traditional passive antennas, these new devices do not require external AC current sources for excitation, thus breaking the current pulse source frequency limitation. Under laser excitation, these devices leverage the photoelectric conversion properties of the substrate material to autonomously generate AC current, thereby generating electromagnetic wave radiation. And the latest research shows that such devices can generate electromagnetic wave radiation at terahertz frequencies.

[0003] However, these devices currently face numerous challenges, including: 1. Difficulty increasing power; 2. Limited modulation methods; and 3. Low sampling sensitivity. Therefore, the specific form of the next-generation millimeter-wave transceiver system requires further exploration. This paper proposes a device design that integrates an entire array of high-frequency pulse sources with a millimeter-wave array antenna. By integrating an optoelectronic pulse source capable of generating electrical pulses exceeding 110 GHz with a passive antenna on the same chip, this device achieves both high-frequency electromagnetic wave radiation and reception, promising applications in wireless communications and radar ranging systems.

[0004] Currently, radiating antenna devices are divided into two categories: active devices and passive devices. Their respective advantages and disadvantages are as follows:

[0005] Passive devices: Advantages: mature design schemes and a wide range of modulation methods; Disadvantages: limited by the 110GHz frequency bottleneck of electrical pulses;

[0006] Active devices: Advantages: The frequency can break through the limitations of electrical pulse sources; Disadvantages: Limited radiation power, few modulation methods, low sampling sensitivity as a receiving module, and difficulty in integrating transceiver functions.

[0007] A comparison of the two types of devices mentioned above shows that the response of specific materials to laser irradiation can generate high-frequency alternating currents, whose frequencies can exceed the limitations of traditional electrical pulse sources. This coincides with the needs of passive antenna devices. However, the transmission of electrical signals between heterogeneous devices will produce huge losses, especially for high-frequency signals. The large amount of loss makes the devices unable to meet the power requirements of people's actual use. Therefore, integration on the same chip has become a more suitable solution. However, such optoelectronic materials are often semiconductors or conductors, which often have large dielectric losses or leakage effects.

[0008] Existing high-frequency electromagnetic wave emitting devices, such as photoconductive antennas and spin terahertz devices, can overcome the frequency limitations of traditional electrical pulse sources. However, they still have many deficiencies in power enhancement, modulation methods, and reception capabilities. Therefore, device design requires special design based on material properties. Here, we use the simulation design software HFSS to complete the integrated design of the pulse source and passive antenna, realizing the radiation and reception functions of high-frequency electromagnetic waves. Summary of the Invention

[0009] The present invention provides a radar array device and method based on on-chip antenna-pulse source integration. The goal of this application is to construct a high-efficiency, low-loss, highly integrated ultrafast integrated antenna array of photoconductive materials to achieve high-frequency millimeter-wave communication, high-precision radar detection, and ultra-high-speed photoelectric detection, so as to solve the problems in the background technology.

[0010] To achieve the above-mentioned object, the present invention provides the following technical solutions: a radar array device based on on-chip antenna-pulse source integration, comprising a radiation structure, a collection structure, a transmission structure and an excitation structure;

[0011] The radiation structure consists of an array of passive antennas, which is used for the mutual conversion of electromagnetic waves and electric currents;

[0012] The acquisition structure, composed of a photoconductive switch, receives electromagnetic signals from the array antenna and converts them into current signals for signal acquisition and transmission;

[0013] The transmission structure uses a low-loss GSG coplanar waveguide to transmit high-frequency current to the array antenna for low-loss transmission;

[0014] The excitation structure is composed of a photoconductive switch, which generates a high-frequency pulse current through laser excitation to excite the array antenna.

[0015] Furthermore, the radiation structure is composed of multiple passive antennas, the number of which can be adjusted according to application requirements.

[0016] Furthermore, the excitation structure is a gap electrode on a photoconductive substrate. By providing a DC bias from the bottom, when the laser irradiates the photoconductive substrate material between the electrode gaps, picosecond electric pulses are excited upward to feed the array antenna.

[0017] Furthermore, the excitation structure increases the output power by increasing the number of excitation structures, and the coupling structure of multiple excitation structures requires a matching transmission structure to be designed for transmission.

[0018] Furthermore, the transmission structure is optimized through electromagnetic simulation to match the transmission of electromagnetic waves of different frequencies and powers.

[0019] Furthermore, the transmission structure adopts a low-loss GSG coplanar waveguide, which is a low-loss transmission line obtained by simulation using electromagnetic simulation software. At the same time, different transmission structures need to be designed according to the input requirements of different radiation structure radiation antennas.

[0020] Furthermore, the collection structure is a gap electrode on a photoconductive substrate, one side of which is a signal collection outlet and the other side of which is a signal input port.

[0021] Furthermore, the signal at the signal input port is obtained by converting the spatial electromagnetic wave collected by the radiating structure antenna into an electrical signal. When there is an electrical signal at the signal input port, the laser irradiates the photoconductive substrate between the gaps, and the signal is transmitted to the signal collection port to complete the signal collection.

[0022] Furthermore, the radiation structure is composed of multiple passive antennas, the number of which can be adjusted according to application requirements and is designed to be no less than one.

[0023] The method of the radar array device based on on-chip antenna-pulse source integration includes the following steps:

[0024] Applying a DC bias to the lower port of the excitation structure to pre-bias the photoconductive switch of the excitation structure;

[0025] Femtosecond laser is used to excite the photoconductive substrate in the gap of the excitation structure to generate high-frequency pulses;

[0026] The high-frequency pulse is transmitted to the radiation structure through the transmission structure, radiating electromagnetic waves outward;

[0027] When external electromagnetic waves are transmitted to the radiating structure, the spatial electromagnetic waves are converted into on-chip currents;

[0028] When the current is transmitted downward through the transmission structure, a voltage bias is applied to the right port of the acquisition structure;

[0029] Femtosecond laser is used to excite the photoconductive switch in the gap of the collection structure to conduct current and complete signal collection.

[0030] Compared with the prior art, the present invention provides a radar array device and method based on on-chip antenna-pulse source integration, which has the following beneficial effects:

[0031] The radar array device and method based on on-chip antenna-pulse source integration have high integration: the excitation, transmission, collection and radiation structures are integrated into one, reducing the complexity of the antenna system; low loss: the transmission loss is reduced through the optimized coplanar waveguide transmission structure; efficient collection: the fast response characteristics of the photoconductive switch are utilized to achieve efficient signal collection; reciprocity: the reciprocity characteristics of the antenna enable the same structure to be used for the transmission and reception of electromagnetic waves. The present application can effectively excite and collect electromagnetic waves, and the bandwidth can be extended to millimeter waves or even higher frequency bands, with a higher signal-to-noise ratio, lower power consumption and smaller size compared to existing technologies. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0033] Figure 1 A schematic diagram of a radiation structure of the present invention;

[0034] Figure 2 It is a schematic diagram of two radiation structures of the present invention;

[0035] In the figure: 1. Radiation structure; 2. Collection structure; 3. Transmission structure; 4. Excitation structure. DETAILED DESCRIPTION

[0036] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0037] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0038] Secondly, the term "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in various places throughout this specification does not necessarily refer to the same embodiment, nor does it constitute a separate or selective embodiment that is mutually exclusive with other embodiments.

[0039] See also Figure 1-2 The present invention discloses a radar array device based on on-chip antenna-pulse source integration, comprising a radiation structure 1, a collection structure 2, a transmission structure 3 and an excitation structure 4;

[0040] The radiation structure 1 is composed of an array of passive antennas and is used for mutual conversion between electromagnetic waves and electric current.

[0041] The acquisition structure 2, composed of a photoconductive switch, receives electromagnetic signals from the array antenna and converts them into current signals for signal acquisition and transmission.

[0042] Transmission structure 3 uses a low-loss GSG coplanar waveguide to transmit high-frequency current to the array antenna for low-loss transmission.

[0043] The excitation structure 4 is composed of a photoconductive switch, which generates a high-frequency pulse current through laser excitation to excite the array antenna.

[0044] The goal of this application is to construct a high-efficiency, low-loss, highly integrated ultrafast integrated antenna array of photoconductive materials to realize a series of potential application scenarios, such as: high-frequency millimeter-wave communications, high-precision radar detection, and ultra-high-speed photoelectric detection.

[0045] The integrated solution of the array antenna and the array photoconductive device of the present application enables excitation and sampling to be completed on the same chip through the cooperation between the array antenna and the array photoconductive device.

[0046] This application achieves its goals through the following methods:

[0047] 1) Based on the characteristics of photoconductive materials, an efficient excitation structure 4, transmission structure 3, and collection structure 2 were designed. These structures were implemented using a gap electrode photoconductive switch and a GSG coplanar waveguide, respectively. Electromagnetic simulation software was used to optimize the structural parameters and reduce transmission losses.

[0048] 2) Use array passive antennas to realize the conversion between the electric pulses generated by photoconductive materials and external electromagnetic waves: effectively stimulate space electromagnetic waves and realize the collection of external space electromagnetic waves.

[0049] Specifically, the excitation structure 4 is a gap electrode on a photoconductive substrate. When a DC bias is provided from the bottom, when the laser irradiates the photoconductive substrate material between the electrode gaps, picosecond electric pulses are excited upward to feed the array antenna. The output power of the excitation structure 4 is increased by increasing the number of excitation structures 4 ( Figure 1 Only 1 incentive structure 4 integration is shown in Figure 2 Only two excitation structures 4 are shown in the figure). The coupling structure of multiple excitation structures 4 requires the design of a matching transmission structure 3 for transmission.

[0050] Specifically, the transmission structure 3 is optimized through electromagnetic simulation to match the electromagnetic wave transmission of different frequencies and powers. The transmission structure 3 adopts a low-loss GSG coplanar waveguide, which is a low-loss transmission line obtained by simulation of electromagnetic simulation software. At the same time, different transmission structures 3 need to be designed according to the input requirements of different radiation structure 1 radiation antennas.

[0051] Specifically, the collection structure 2 is a gap electrode on a photoconductive substrate, with a signal collection outlet on the left and a signal input port on the right. The signal at the signal input port is obtained by converting the spatial electromagnetic wave collected by the antenna of the radiation structure 1 into an electrical signal. When there is an electrical signal at the signal input port, the laser irradiates the photoconductive substrate between the gaps, and the signal is transmitted to the signal collection outlet to complete the signal collection.

[0052] Specifically, the radiation structure 1 is composed of multiple passive antennas, the number of which can be adjusted according to application requirements and is designed to be no less than one.

[0053] Specifically, the laser input of the excitation structure 4 and the collection structure 2 can be free-space light, which can be replaced by an on-chip silicon optical waveguide input.

[0054] Specifically, the light collection module of the collection structure 2 can be replaced by a purely electrical collection solution of a radio frequency circuit.

[0055] Specifically, for the low frequency band, the transmission structure 3 can replace the coplanar waveguide with a microstrip line.

[0056] During use: a femtosecond laser is used to vertically illuminate the gap on the photoconductive switch excitation structure 4 to excite the photoconductive material to generate a high-frequency pulse current; the high-frequency current is transmitted to the array antenna through a well-designed transmission structure 3; the array antenna converts the high-frequency current into a spatial electromagnetic wave and radiates it outward; when external electromagnetic waves or signals of a specific frequency are irradiated onto the array antenna, the antenna principle converts the electromagnetic wave into an on-chip current according to the reciprocity characteristic, causing it to flow through the transmission structure 3 and reach the collection structure 2; when the voltage bias of the collection structure 2 reaches a certain threshold, the laser irradiates the gap of the collection structure 2, turns on the photoconductive switch, and collects and transmits the received current.

[0057] The method of the radar array device based on the on-chip antenna-pulse source integration is specifically an electromagnetic wave excitation and acquisition method, comprising the following steps:

[0058] Applying a DC bias to the lower port of the excitation structure 4 to pre-bias the photoconductive switch of the excitation structure 4;

[0059] A femtosecond laser is used to excite the photoconductive substrate in the gap of the excitation structure 4 to generate a high-frequency pulse;

[0060] The high-frequency pulse is transmitted to the radiation structure 1 through the transmission structure 3, and radiates electromagnetic waves outward;

[0061] When external electromagnetic waves are transmitted to the radiation structure 1, the space electromagnetic waves are converted into on-chip currents;

[0062] When the current passes through the transmission structure 3 and reaches the right port of the collection structure 2, it provides a voltage bias for the photoconductive switch of the collection structure 2;

[0063] The femtosecond laser is used to excite the photoconductive switch in the gap of the collection structure 2 to conduct the current and complete the signal collection.

[0064] The method of a radar array device based on on-chip antenna-pulse source integration includes the following steps:

[0065] Applying a DC bias to the lower port of the excitation structure 4 to pre-bias the photoconductive switch of the excitation structure 4;

[0066] A femtosecond laser is used to excite the photoconductive substrate in the gap of the excitation structure 4 to generate a high-frequency pulse;

[0067] The high-frequency pulse is transmitted to the radiation structure 1 through the transmission structure 3, and radiates electromagnetic waves outward;

[0068] When external electromagnetic waves are transmitted to the radiation structure 1, the space electromagnetic waves are converted into on-chip currents;

[0069] When the current is transmitted downward through the transmission structure 3, a voltage bias is applied to the right port of the acquisition structure 2;

[0070] The photoconductive switch in the gap of the collection structure 2 is excited by a femtosecond laser to conduct current and complete signal collection.

[0071] The technical solution of this patent application mainly adopts the following design ideas:

[0072] Adopting a feedback structure: by applying DC bias and laser signal, the conductive properties of the photoconductive material are controlled, thereby achieving efficient signal transmission and reception.

[0073] Exquisite transmission design: Through the carefully designed coplanar waveguide circuit, the loss during transmission is reduced, ensuring efficient signal transmission.

[0074] Optimized acquisition structure: By designing a specific photoconductive switch structure, it is not only possible to quickly acquire feedback signals, but also to effectively reduce noise interference.

[0075] Radiating structure 1- Array passive antenna used to transmit and receive electromagnetic waves.

[0076] Transmission structure 3 - coplanar waveguide, used to transmit electrical signals.

[0077] Acquisition structure 2 - photoconductive switch, used to collect feedback signals.

[0078] Excitation structure 4 - photoconductive switch, used to generate high-frequency pulses.

[0079] This application achieves a significant improvement in transmission efficiency through feedback structure design while maintaining low energy consumption and miniaturization of the device;

[0080] How to achieve it: Optimize the transmission structure and reduce losses through carefully designed electromagnetic simulation software; optimize the acquisition structure through feedback design to improve signal reliability.

[0081] Implementation description: This technical solution achieves efficient and low-loss electromagnetic wave collection and emission by integrating photoconductive switches, transmission structures, collection structures, and radiation structures. Its compact structure makes it easy to integrate into a system-on-chip.

[0082] In summary, the radar array device and method based on on-chip antenna-pulse source integration have high integration: the excitation, transmission, acquisition and radiation structures are integrated into one, reducing the complexity of the antenna system; low loss: the transmission loss is reduced by optimizing the coplanar waveguide transmission structure 3; efficient acquisition: the fast response characteristics of the photoconductive switch are utilized to achieve efficient signal acquisition; reciprocity: the reciprocity characteristics of the antenna enable the same structure to be used for the transmission and reception of electromagnetic waves. The present application can effectively excite and collect electromagnetic waves, and the bandwidth can be extended to millimeter waves or even higher frequency bands, with higher signal-to-noise ratio, lower power consumption and smaller size compared with the existing technology.

[0083] It should be understood that various parts of the present invention can be implemented using hardware, software, firmware, or a combination thereof. In the above-described embodiments, multiple steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used: a discrete logic circuit having logic gate circuits for implementing logic functions on data signals, an application-specific integrated circuit having suitable combinational logic gate circuits, a programmable gate array (PGA), a field-programmable gate array (FPGA), etc.

[0084] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A radar array device based on on-chip antenna-pulse source integration, characterized by: Including radiation structure, collection structure, transmission structure and excitation structure; The radiation structure consists of an array of passive antennas, which is used for the mutual conversion of electromagnetic waves and electric currents; The acquisition structure, composed of a photoconductive switch, receives electromagnetic signals from the array antenna and converts them into current signals for signal acquisition and transmission; The transmission structure uses a low-loss GSG coplanar waveguide to transmit high-frequency current to the array antenna for low-loss transmission; The excitation structure is composed of a photoconductive switch, which generates a high-frequency pulse current through laser excitation to excite the array antenna.

2. The radar array device based on on-chip antenna-pulse source integration according to claim 1, characterized in that: The excitation structure is a gap electrode on a photoconductive substrate. When a DC bias is provided from the bottom, when the laser irradiates the photoconductive substrate material between the electrode gaps, picosecond electric pulses are excited upward to feed the array antenna.

3. The radar array device based on on-chip antenna-pulse source integration according to claim 2, characterized in that: The excitation structure increases the output power by increasing the number of excitation structures, and the coupling structure of multiple excitation structures requires a matching transmission structure to be designed for transmission.

4. The radar array device based on on-chip antenna-pulse source integration according to claim 1, characterized in that: The transmission structure is optimized through electromagnetic simulation to match the transmission of electromagnetic waves of different frequencies and powers.

5. The radar array device based on on-chip antenna-pulse source integration according to claim 4, characterized in that: The transmission structure uses a low-loss GSG coplanar waveguide, which is a low-loss transmission line obtained by simulation using electromagnetic simulation software. Different transmission structures need to be designed according to the input requirements of different radiation structure radiating antennas.

6. The radar array device based on on-chip antenna-pulse source integration according to claim 1, characterized in that: The collection structure is a gap electrode on a photoconductive substrate, one side of which is a signal collection outlet and the other side is a signal input port.

7. The radar array device based on on-chip antenna-pulse source integration according to claim 6, characterized in that: The signal at the signal input port is obtained by converting the spatial electromagnetic wave collected by the radiating structure antenna into an electrical signal. When there is an electrical signal at the signal input port, the laser irradiates the photoconductive substrate between the gaps, and the signal is transmitted to the signal collection port to complete the signal collection.

8. The radar array device based on on-chip antenna-pulse source integration according to claim 1, characterized in that: The radiation structure is composed of multiple passive antennas, the number of which can be adjusted according to application requirements and is designed to be no less than one.

9. The method for a radar array device based on on-chip antenna-pulse source integration according to any one of claims 1 to 8, characterized in that: The following steps are involved: Applying a DC bias to the lower port of the excitation structure to pre-bias the photoconductive switch of the excitation structure; Femtosecond laser is used to excite the photoconductive substrate in the gap of the excitation structure to generate high-frequency pulses; The high-frequency pulse is transmitted to the radiation structure through the transmission structure, radiating electromagnetic waves outward; When external electromagnetic waves are transmitted to the radiating structure, the spatial electromagnetic waves are converted into on-chip currents; When the current is transmitted downward through the transmission structure, a voltage bias is applied to the right port of the acquisition structure; Femtosecond laser is used to excite the photoconductive switch in the gap of the collection structure to conduct current and complete signal collection.

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