Millimeter wave multi-channel delay assembly

Abstract

The invention discloses a millimeter wave multichannel delay assembly, which comprises a control and modulation drive circuit, a whole delay amplification link comprises a main path five-bit delay amplification link and four channel five-bit delay amplification links, and power distribution and synthesis between a main path and channels are carried out by a one-to-four power distribution and synthesis network; the main path 5-bit delay amplification link comprises a 1-wavelength delay bit, a 2-wavelength delay bit, a 4-wavelength delay bit, an 8-wavelength delay bit, a 16-wavelength delay bit and a two-stage amplifier; each channel five-bit delay amplification link comprises a 0.25 wavelength, a 0.5 wavelength, a 1 wavelength, a 2 wavelength, a 2 wavelength delay bit and a two-stage amplifier, and the control and modulation driving circuit can independently control the delay amplification functions of the main path five-bit delay amplification link and the four channel five-bit delay amplification links. According to the millimeter wave four-channel delay assembly, the miniaturization, high-precision and high-reliability design of the millimeter wave four-channel delay assembly is realized, the array plane integration level can be effectively improved, and meanwhile, the high-precision performance index of the array plane is met.

Description

Technical Field

[0001] The present invention relates to antenna and microwave technologies, and particularly to a millimeter-wave multi-channel delay component. Background Art

[0002] The main functions of the delay component in a radar system are to provide real-time delay for the array surface, compensate for the transit time of the array surface, and amplify radio frequency signals.

[0003] Currently, delay components mainly focus on the Ku band and below. The article "Design and Implementation of a Subarray Drive Delay Component for X-Band Active Phased Array Radar" (authors Li Shuliang, Zhu Runyue, Liu Yang, "Modern Radar", 2016, Vol. 38, No. 7) discloses an active phased array delay component, the method of which is to use a microwave multilayer board to achieve 5-bit delay (1 / 2 / 4 / 8 / 16 wavelengths) in the X band. The disadvantage of such delay components is that they cannot meet the requirements of millimeter-wave radar systems. Under the same stack structure, the insertion loss of the delay line per unit length in the millimeter-wave band is more than 10 times that in the X band. To compensate for the above delay loss, amplifier chips with higher gain need to be selected in the link. However, when high-gain chips are cascaded, self-oscillation is likely to occur due to spatial coupling, and corresponding measures must be taken during design to avoid the generation of self-oscillation.

[0004] At the same time, as the antenna aperture and the number of component channels of active phased array radars are gradually increasing, multi-channel delay components are required to improve the delay compensation density of the array surface. The article "Implementation of a Miniaturized Millimeter-Wave Delay Component" (authors Lin Weitao, Li Shuliang, "Modern Radar", 2020, Vol. 42, No. 1, pp. 64-66) introduces a method for implementing a millimeter-wave delay component. This component uses a switch + amplifier + strip line form to achieve delay amplitude-phase switching and gain compensation. However, the disadvantage of this design is that it cannot meet the requirements of multi-channel high-precision compensation. The multi-channel operation of the delay component involves issues such as independent control of the delay states of each channel, independent modulation of the drive circuit, reasonable layout of the delay circuit, and effective isolation of radio frequency amplification between channels, rather than a direct splicing of single-channel delays.

[0005] In summary, there are limitations in the multi-channel design of current delay components in the millimeter-wave band. Summary of the Invention

[0006] In view of the problems existing in the prior art, the present invention provides a multi-channel delay component operating in the millimeter-wave band. The present invention realizes the miniaturized, high-precision, and highly reliable design of a millimeter-wave four-channel delay component, which can effectively improve the integration of the array surface and meet the high-precision performance indicators of the array surface at the same time.

[0007] The object of the present invention is achieved through the following technical solutions.

[0008] A millimeter-wave multi-channel delay component includes a control and modulation drive circuit. The entire delay amplification link includes a main path 5-bit delay amplification link and 4-channel 5-bit delay amplification links. A one-to-four power distribution and synthesis network is used for power distribution and synthesis between the main path and the channels. The main path 5-bit delay amplification link includes 1-wavelength, 2-wavelength, 4-wavelength, 8-wavelength, 16-wavelength delay bits and two-stage amplifiers. Each of the 4-channel 5-bit delay amplification links includes 0.25-wavelength, 0.5-wavelength, 1-wavelength, 2-wavelength, 2-wavelength delay bits and two-stage amplifiers. The control and modulation drive circuit can independently control the delay amplification functions on the main path 5-bit delay amplification link and the 4-channel 5-bit delay amplification links.

[0009] The 4-channel 5-bit delay amplification link adopts the form of cavity excavation on the LTCC substrate. Two-stage amplifiers and 0.25-wavelength, 0.5-wavelength, 1-wavelength, 2-wavelength, 2-wavelength delay chips are integrated in two shielding cavities with sizes of only 5.2mm * 7.5mm * 0.8mm and 5.2mm * 4.1mm * 0.8mm respectively. Each channel can be independently controlled by a multi-channel control chip.

[0010] The millimeter-wave LTCC stepped interconnection method is adopted: A microwave board transition piece with microstrip lines printed on its surface and several square debugging blocks printed on both sides of the microstrip lines is welded to the shell step at one end and to the step inside the LTCC substrate cavity at the other end. One end of the microstrip line on the transition piece is welded to the inner conductor of the connector, and the other end is interconnected with the microstrip line inside the LTCC substrate cavity through gold wire bonding for the transmission transition of radio frequency signals.

[0011] The 1-wavelength, 2-wavelength, 4-wavelength, 8-wavelength delay bits of the main path 5-bit delay amplification link are realized by gallium arsenide chips, and the 16-wavelength delay bit is realized by a coplanar waveguide - stripline transmission structure. The 0.25-wavelength, 0.5-wavelength, 1-wavelength, 2-wavelength, 2-wavelength delay lines on each of the 4-channel 5-bit delay amplification links are realized by gallium arsenide chips. The amplification compensation of the delay loss is realized by a gallium arsenide multi-functional bidirectional amplifier chip and is directly cascaded with the delay chips. Each chip is directly glued to the surface of the LTCC substrate shielding cavity.

[0012] Compared with the prior art, the advantages of the present invention are as follows:

[0013] 1. Multi-channel: The multi-channel delay component of the present invention is based on the LTCC substrate and realizes the control, amplification, and delay functions on the main path and four channels. The maximum delay amount of 31 wavelengths is realized on the main path, and the maximum delay amount of 5.75 wavelengths is realized on each channel. The layout of the delay lines is compact, and the integration degree of the component is high;

[0014] 2. Miniaturization and High Performance: The 1 / 2 / 4 / 8-wavelength delay units on the main path and the 0.25 / 0.5 / 1 / 2 / 2-wavelength delay units on the channels of the present invention are implemented using gallium arsenide chips. The 16-wavelength delay unit on the main path is implemented using a coplanar waveguide - stripline structure, enabling a balance among size, performance, and processability.

[0015] 3. High Reliability: The main path of the present invention includes two stages of amplifiers, and each of the four channels includes two stages of amplifiers, for a total of four stages of amplifiers. The components use a shielding cavity, a shielding cover plate, and absorbers to improve spatial isolation and reduce the risk of amplifier self-oscillation. Description of the Drawings

[0016] Figure 1 is a radio frequency principle block diagram.

[0017] Figure 2 is a control principle block diagram.

[0018] Figure 3 is an assembly schematic diagram of a millimeter-wave multi-channel delay component.

[0019] Figure 4 is a laminated diagram of a low-temperature co-fired ceramic substrate.

[0020] Figure 5 is an LTCC stepped interconnection model. Detailed Embodiments

[0021] The present invention will be described in detail below in conjunction with the drawings of the specification and specific embodiments.

[0022] A millimeter-wave multi-channel delay component includes a control and modulation drive circuit. The entire delay amplification link includes a 5-bit delay amplification link on the main path and 4 5-bit delay amplification links on the channels. A one-to-four power distribution and synthesis network is used for power distribution and synthesis between the main path and the channels. The 5-bit delay amplification link on the main path includes 1-wavelength, 2-wavelength, 4-wavelength, 8-wavelength, 16-wavelength delay units and two stages of amplifiers. Each of the 5-bit delay amplification links on the channels includes 0.25-wavelength, 0.5-wavelength, 1-wavelength, 2-wavelength, 2-wavelength delay units and two stages of amplifiers, realizing a 0.25-wavelength step in the millimeter-wave band and a maximum delay of 36.75 wavelengths. It realizes the delay control, power amplification, and transceiver conversion of radio frequency transceiver signals. The control and modulation drive circuit can independently control the delay amplification functions on the 5-bit delay amplification link on the main path and the 4 5-bit delay amplification links on the channels.

[0023] The 5-bit delay amplification link of the channel features miniaturization. In the form of cavity excavation on a low-temperature co-fired ceramic (LTCC) substrate, two-stage amplifiers and 0.25-wavelength, 0.5-wavelength, 1-wavelength, 2-wavelength, and 2-wavelength delay chips are integrated in two shielded cavities with dimensions of only 5.2mm * 7.5mm * 0.8mm and 5.2mm * 4.1mm * 0.8mm. The 1:4 power distribution (synthesis) network and the delay amplification chip are designed in the inner-layer cavity of the substrate and interconnected through strip lines. The wave control and power components are integrally installed on the surface layer of the substrate, and the signals are interconnected and transmitted in the inner layer of the substrate; each channel can be independently controlled by a multi-channel control chip. Under the conditions of high loss and low excitation in the millimeter-wave frequency band, the expected performance is achieved in a compact space.

[0024] The millimeter-wave LTCC step interconnection method is adopted: A microwave board transition piece with microstrip lines printed on its surface and several square debugging blocks printed on both sides of the microstrip lines is welded at one end to the shell step and at the other end to the step in the LTCC substrate cavity; one end of the microstrip line on the transition piece is welded to the inner conductor of the connector, and the other end is interconnected with the microstrip line in the LTCC substrate cavity through gold wire bonding for the transmission transition of radio frequency signals. Several tuning blocks are arranged on both sides of the microstrip line on the transition piece, improving the debuggability of the delay component. This method overcomes the lack of debugging means caused by directly welding the inner conductor of the connector to the microstrip line in the LTCC substrate cavity, increases the debuggability of the delay component, and is beneficial to improving the component performance.

[0025] The 1-wavelength, 2-wavelength, 4-wavelength, and 8-wavelength delay bits of the main path 5-bit delay amplification link are realized by gallium arsenide chips, and the 16-wavelength delay bit is realized by a coplanar waveguide - strip line transmission structure; the 0.25-wavelength, 0.5-wavelength, 1-wavelength, 2-wavelength, and 2-wavelength delay lines on each channel's 5-bit delay amplification link are realized by gallium arsenide chips, and the amplification compensation of the delay loss is realized by a gallium arsenide multifunctional bidirectional amplifier chip and is directly cascaded with the delay chip. Each chip is directly glued to the surface of the LTCC substrate shield cavity. Saving the wiring area, the miniaturization of the component is achieved. Shield covers and absorbers are arranged on each shield cavity, improving the electromagnetic environment of the amplifier.

[0026] Figure 1 It is a radio frequency principle block diagram. After the transmitted signal is input from the transmit input port, it sequentially passes through amplifier A, 1 / 2 / 4 / 8-wavelength delay bits, amplifier B, 16-wavelength delay bit, a one-to-four power divider, amplifier C, 0.5 / 1 / 2 / 2-wavelength delay bits, and amplifier D and then outputs; the received signal is input from the receive input port in the opposite direction and sequentially passes through amplifier D, 0.5 / 1 / 2 / 2-wavelength delay bits, amplifier C, power divider, 16-wavelength delay bit, amplifier B, 1 / 2 / 4 / 8-wavelength delay bits, amplifier A, and power divider and then outputs.

[0027] Figure 2 It is a control principle block diagram. After the control signal and power supply signal enter the multi-channel control chip, the first channel outputs an independent transceiver switching signal to Amplifier A and Amplifier B to control the receive / transmit state of the amplifiers. At the same time, a signal is output to the transceiver modulation chip, and then power is supplied to each stage of the amplifier. The second to fifth channels of the control chip output independent transceiver switching signals to Amplifier C and Amplifier D of each channel to control the receive / transmit state of the amplifiers. At the same time, a signal is output to the transceiver modulation chip, and then power is supplied to each stage of the amplifier. The control chip outputs 1 / 2 / 4 / 8 / 16 wavelength delay bits on the main path of the delay control signal and 0.25 / 0.5 / 1 / 2 / 2 delay bits on each channel.

[0028] Figure 3 It is an assembly schematic diagram. The 1 / 2 / 4 / 8 wavelength delay chip on the main path and Amplifier A are located in the same shielding cavity (at A); Amplifier B and the switch for switching between the 16-wavelength delay state and the ground state are located in the same shielding cavity (at B), and the 16-wavelength delay line is implemented in the LTCC substrate in the form of a strip line; Three power dividers located in independent shielding cavities form a one-to-four power division network (at C), the main port is interconnected with the main path, and the branch ports are interconnected with each channel; Amplifier C on the channel is located in an independent shielding cavity (at D), and Amplifier D and the 0.25 / 0.5 / 1 / 2 / 2 wavelength delay chip are located in the same shielding cavity (at E). Each shielding cavity improves the spatial isolation through a shielding cover plate and an absorber. The control chip (at F), the transceiver modulation chip (at G), etc. are located on the surface of the substrate to independently control the amplifiers and delay states of the main path and each channel.

[0029] Figure 4 It is an LTCC substrate stack-up diagram, which consists of 17 layers of LTCC substrates with a thickness of 0.1 mm each, totaling 1.7 mm. There are 18 metal layers in total, including the surface layer (for mounting devices), the low-frequency layer (layers 2 - 8), the RF layer (layers 9 and 15), the ground layer (layers 12 and 18), and the remaining layers are blank boards. The signals in the low-frequency layer are control signals and power supply signals; the signals in the RF layer are RF signals. Each shielding cavity is formed by digging a cavity in the 1st - 8th layers of the substrate to provide good spatial isolation for the amplifier. The shielding cavity is covered with a shielding cover plate, and the shielding cover plate is embedded with an absorber, which can improve the electromagnetic environment where the high-gain amplifier is located and avoid electromagnetic leakage.

Claims

1. A millimeter wave multi-channel delay component, including a control and modulation drive circuit, characterized in that: The entire delay amplification link includes a main 5-bit delay amplification link and 4 channel 5-bit delay amplification links, and the power distribution and synthesis between the main path and the channel are performed by a one-to-four power distribution and synthesis network; the main 5-bit delay amplification link includes 1 wavelength, 2 wavelengths, 4 wavelengths, 8 wavelengths, 16 wavelengths delay positions and a two-stage amplifier; each channel 5-bit delay amplification link includes 0.25 wavelength, 0.5 wavelength, 1 wavelength, 2 wavelengths, 2 wavelengths delay positions and a two-stage amplifier, and the control and modulation drive circuit can independently control the delay amplification function on the main 5-bit delay amplification link and the 4 channel 5-bit delay amplification links.

2. A millimeter wave multi-channel delay component according to claim 1, characterized in that: The channel 5-bit delay amplification link adopts the form of LTCC substrate cavity digging, integrating the two-stage amplifier and 0.25 wavelength, 0.5 wavelength, 1 wavelength, 2 wavelength, and 2 wavelength delay chips in two shielded cavities with sizes of only 5.2mm*7.5mm*0.8mm and 5.2mm*4.1mm*0.8mm. Each channel can be independently controlled by a multi-channel control chip.

3. The millimeter wave multi-channel delay component according to claim 1, characterized in that: A millimeter-wave LTCC step interconnection method is adopted: a microwave board transition piece with a microstrip line printed on the surface and several square debugging blocks printed on both sides of the microstrip line is welded to the shell step at one end and to the step inside the LTCC substrate cavity at the other end; one end of the microstrip line on the transition piece is welded to the conductor inside the connector, and the other end is interconnected with the microstrip line in the LTCC substrate cavity through gold wire bonding, which is used for the transmission transition of RF signals.

4. A millimeter wave multi-channel delay component according to claim 3, characterized in that: The 1-wavelength, 2-wavelength, 4-wavelength, and 8-wavelength delay bits of the main 5-bit delay amplification link are realized through gallium arsenide chips, and the 16-wavelength delay bit is realized through a coplanar waveguide-stripline transmission structure; the 0.25-wavelength, 0.5-wavelength, 1-wavelength, 2-wavelength, and 2-wavelength delay lines on the 5-bit delay amplification link of each channel are realized through gallium arsenide chips, and the amplification compensation of delay loss is achieved through a gallium arsenide multifunctional bidirectional amplifier chip, which is directly cascaded with the delay chip, and each chip is directly glued to the surface of the shielding cavity of the LTCC substrate.

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