A radio frequency architecture for a terahertz active phased array

Abstract

This invention discloses a terahertz active phased array radio frequency architecture. Its core components include a system amplitude and phase synchronization control unit, an intermediate frequency amplitude and phase control unit array, a local oscillator phase-shifting channel unit array, and a terahertz frequency conversion unit array. The system amplitude and phase synchronization control unit ensures coordinated operation of all units in the architecture. The intermediate frequency amplitude and phase control unit array transmits and receives the intermediate frequency signals required by the terahertz transceiver array. The terahertz frequency conversion unit array performs up-conversion and down-conversion switching of the terahertz signal. The local oscillator phase-shifting channel unit array provides the local oscillator for the terahertz frequency conversion unit array. This invention proposes an active phased array radio frequency architecture suitable for the terahertz band. This architecture avoids the use of attenuators and phase shifters in the terahertz band, reducing losses; it improves the scanning accuracy of the phase shifter and enhances the beam scanning function of the phased array; compared with general phased arrays, this architecture can be used in high linearity and saturation states, meeting the requirements for both communication and radar applications.

Description

Technical Field

[0001] This invention belongs to the field of terahertz phased array technology, specifically relating to a radio frequency architecture for a terahertz active phased array. Background Technology

[0002] Phased array technology is a technique that uses phase compensation or delay adjustment to adjust each array element, thereby adjusting the performance of an array of a certain size. It can be divided into receiving phased arrays and transmitting phased arrays. However, whether it is a receiving phased array or a transmitting phased array, its overall architecture is similar. The working principle can be summarized as applying appropriate phase shift (or delay) to the signals of array elements arranged in a certain pattern to obtain the deflection of the array beam. By simultaneously performing phase (or delay) compensation in different directions, multi-beam can be obtained.

[0003] Current phased array technology mainly focuses on the Ka band and below, especially in microwave applications. Existing phased array systems primarily rely on the phased array antenna subsystem to achieve radio frequency phase shifting and beamforming. The phased array antenna changes the shape of its radiation pattern by controlling the feed phase of the radiating elements within the array antenna. This method not only alters the direction of the antenna's maximum radiation value to achieve beam scanning but also allows for rapid changes in the direction of the maximum radiation value or other parameters through computer control. The phased array antenna is the foundation of modern phased array systems, and its key components are the phase shifter and the antenna radiating elements.

[0004] Currently, the communications field has gradually opened up the Ka band (20-40GHz) and Q band (30-50GHz), while also exploring the V band (50-75GHz). The radar field is also gradually developing from the X band to Ka, W, and even bands above 100GHz. Particularly in areas such as autonomous driving in civilian vehicles and intelligent detection and sensing, there is a significant demand for the 77GHz band. This vast application market will inevitably drive research to cover even higher frequency bands. It is expected that within the next three years, millimeter-wave RF front-ends in the E (60-90GHz) to W (75-110GHz) bands will be commercialized. Therefore, with technological advancements, the demand for high-frequency phased arrays in the millimeter-wave / terahertz bands will gradually emerge. However, existing phased array antenna research mainly focuses on the L, S, C, and X bands. The RF architecture based on phased array antennas is no longer fully suitable for the current state and future of high-frequency bands, necessitating a new architecture to supplement the current RF architecture of phased array systems. Summary of the Invention

[0005] In view of this, the present invention proposes a radio frequency architecture for a terahertz active phased array, which solves the problem that the performance of RF (radio frequency) phase shifters rapidly decreases as the frequency increases. In the absence of phase shifters in the terahertz band, a usable high-precision terahertz phased array radio frequency architecture is constructed.

[0006] To achieve this objective, the present invention adopts the following technical solution: a radio frequency architecture for a terahertz active phased array, the architecture comprising: a baseband digital system, an intermediate frequency unit, a microwave unit, and a terahertz unit;

[0007] The baseband digital system includes a baseband transmitter, a signal processing unit, and a baseband receiver connected in sequence, as well as a system amplitude and phase synchronization control unit;

[0008] The intermediate frequency unit includes an intermediate frequency synthesis network, an intermediate frequency transceiver array, and an intermediate frequency amplitude and phase control unit array connected in sequence; wherein the intermediate frequency transceivers in the intermediate frequency transceiver array and the intermediate frequency amplitude and phase control units in the intermediate frequency amplitude and phase control unit array are connected in a one-to-one correspondence;

[0009] The microwave unit includes a frequency synthesizer unit and a local oscillator frequency doubling channel unit connected in sequence;

[0010] The terahertz unit includes a local oscillator feed network, a local oscillator phase-shifting channel unit array, and a terahertz frequency conversion unit array connected in sequence, wherein the local oscillator phase-shifting channel unit in the local oscillator phase-shifting channel unit array is connected to the terahertz frequency conversion unit in the terahertz frequency conversion unit array in a one-to-one correspondence.

[0011] The baseband transmitter and baseband receiver are connected to an intermediate frequency synthesis network;

[0012] The frequency amplitude phase control unit in the intermediate frequency amplitude phase control unit array is connected one-to-one with the terahertz frequency conversion unit in the terahertz frequency conversion unit array.

[0013] The local oscillator frequency doubling channel unit is connected to the local oscillator feed network;

[0014] The system amplitude and phase synchronization control unit is connected to each terahertz frequency converter and the intermediate frequency amplitude and phase control unit.

[0015] Preferably, the terahertz frequency conversion unit includes a mixer, a first terahertz switching switch, a medium power amplifier, a low noise amplifier, and a second terahertz switching switch; the medium power amplifier and the low noise amplifier are connected in parallel between the first terahertz switching switch and the second terahertz switching switch, the other end of the first terahertz switching switch is connected to the mixer, and the other end of the second terahertz switching switch is connected to the antenna.

[0016] Preferably, the intermediate frequency amplitude and phase control unit includes a millimeter-wave switching switch, an adjustable attenuator, a phase shifter, an amplifier, and a low-noise amplifier; the adjustable attenuator, phase shifter, and amplifier form an up-conversion channel, and the adjustable attenuator, phase shifter, and low-noise amplifier form a down-conversion channel. The up-conversion channel and the down-conversion channel are arranged in parallel between two millimeter-wave switching switches, wherein the other end of the first millimeter-wave switching switch is connected to the corresponding intermediate frequency transceiver, and the other end of the second millimeter-wave switching switch is connected to the mixer of the corresponding terahertz frequency conversion unit.

[0017] Preferably, the local oscillator phase-shifting channel unit includes a frequency multiplier, an amplifier, a filter, a millimeter-wave power divider network, an amplifier array, an adjustable attenuator array, and a phase shifter array connected in sequence;

[0018] The amplifiers, adjustable attenuators, and phase shifters in the amplifier array, adjustable attenuator array, and phase shifter array are connected in a one-to-one correspondence in sequence.

[0019] The outputs of the phase shifter array are all connected to the mixers of the corresponding terahertz frequency conversion units.

[0020] Preferably, the connection order of the adjustable attenuator, phase shifter and amplifier in the upconversion channel can be adjusted according to the actual situation.

[0021] Preferably, the millimeter-wave switching switch can be replaced with a millimeter-wave circulator.

[0022] The beneficial effects of this invention are as follows: This invention proposes a radio frequency architecture for a terahertz active phased array, which is suitable for the terahertz frequency band. This architecture avoids the use of attenuators and phase shifters in the terahertz frequency band, thus reducing losses. This architecture improves the scanning accuracy of the phase shifter and enhances the beam scanning function of the phased array. Compared with general phased arrays, this architecture can be used in high linearity and saturation states, which is suitable for both communication and radar applications. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the radio frequency architecture of the terahertz active phased array in an embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram of the terahertz frequency conversion unit in an embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of the intermediate frequency amplitude phase control unit in an embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram of the structure of the phase-shifting channel unit in an embodiment of the present invention. Detailed Implementation

[0027] Those skilled in the art will recognize that the embodiments described herein are intended to help the reader understand the principles of the invention, and should be understood that the scope of protection of the invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific modifications and combinations based on the technical teachings disclosed in this invention without departing from the spirit of the invention, and these modifications and combinations are still within the scope of protection of this invention.

[0028] The present application will be further described below with reference to the embodiments and accompanying drawings.

[0029] See Figure 1 A terahertz active phased array radio frequency architecture includes: a baseband digital system, an intermediate frequency unit, a microwave unit, and a terahertz unit; wherein the baseband digital system includes a baseband transmitter, a signal processing unit, and a baseband receiver connected in sequence, as well as a system amplitude and phase synchronization control unit;

[0030] The intermediate frequency (IF) unit comprises an IF synthesis network, an IF transceiver array, and an IF amplitude phase control unit array connected in sequence; wherein the IF transceivers in the IF transceiver array and the IF amplitude phase control units in the IF amplitude phase control unit array are connected in a one-to-one correspondence.

[0031] The microwave unit consists of a frequency synthesizer unit and a local oscillator frequency doubling channel unit connected in sequence;

[0032] The terahertz unit includes a local oscillator feed network, a local oscillator phase-shifting channel unit array, and a terahertz frequency conversion unit array connected in sequence, wherein the local oscillator phase-shifting channel unit in the local oscillator phase-shifting channel unit array is connected to the terahertz frequency conversion unit in the terahertz frequency conversion unit array in a one-to-one correspondence.

[0033] The aforementioned baseband transmitter and baseband receiver are connected to the intermediate frequency synthesis network; the frequency amplitude and phase control unit in the intermediate frequency amplitude and phase control unit array is connected one-to-one with the terahertz frequency conversion unit in the terahertz frequency conversion unit array, providing intermediate frequency signals to the mixer of the terahertz frequency conversion unit; the local oscillator frequency doubling channel unit is connected to the local oscillator feed network; the system amplitude and phase synchronization control unit is connected to each terahertz frequency conversion unit and the intermediate frequency amplitude and phase control unit, controlling the time-division control, phase shifter control and switching of these units, so that the entire architecture operates in a coordinated manner.

[0034] As an example, such as Figure 2 As shown, the terahertz frequency conversion unit includes a mixer, a first terahertz switching switch, a medium power amplifier, a low noise amplifier, and a second terahertz switching switch; the medium power amplifier and the low noise amplifier are connected in parallel between the first terahertz switching switch and the second terahertz switching switch, the other end of the first terahertz switching switch is connected to the mixer, and the other end of the second terahertz switching switch is connected to the antenna.

[0035] The core function of this unit is to realize the up-conversion and down-conversion switching of terahertz signals, including: ① up-conversion and down-conversion mixing unit; ② switching power amplifier transmission channel and low-noise amplifier reception channel. Functionally, it mainly utilizes a time-division multiplexing mechanism. When the phased array is in the transmission phase, the mixer automatically turns on for up-conversion, and the signal is selected to the power amplifier channel by the switching switch. The signal is then transmitted through the antenna. When the phased array is in the reception phase, the signal is fed from the antenna into the switching switch and selected to the low-noise amplifier channel. The signal then enters the mixer and automatically turns on for down-conversion, completing the reception and frequency conversion of the terahertz signal.

[0036] As an example, such as Figure 3 As shown, the intermediate frequency amplitude and phase control unit includes a millimeter-wave switching switch, an adjustable attenuator, a phase shifter, an amplifier, and a low-noise amplifier. The adjustable attenuator, phase shifter, and amplifier form an up-conversion channel, and the adjustable attenuator, phase shifter, and low-noise amplifier form a down-conversion channel. The up-conversion channel and the down-conversion channel are arranged in parallel between two millimeter-wave switching switches. The other end of the first millimeter-wave switching switch is connected to the corresponding intermediate frequency transceiver, and the other end of the second millimeter-wave switching switch is connected to the mixer of the corresponding terahertz frequency conversion unit.

[0037] The core function of this unit is to transmit and receive the intermediate frequency (IF) signal required by the terahertz transceiver array. In practice, the adjustable attenuator, phase shifter, and amplifier in the upconversion channel can be adjusted according to the actual situation, and the millimeter-wave switching switch can also be changed to a millimeter-wave circulator. Specifically, it still operates in a switching time-division multiplexing mode. When the phased array is in the transmit state, the millimeter-wave switching switch switches to the upconversion channel, that is, it enters the adjustable attenuation, phase shift, and amplification path, and finally enters the terahertz mixer IF to complete the upconversion. When the phased array enters the receive state, the millimeter-wave switching switch switches to the downconversion channel, that is, the signal enters the low-noise amplifier, phase shifter, and adjustable attenuator to complete the terahertz downconversion IF signal processing.

[0038] As an example, such as Figure 4 As shown, the local oscillator phase-shifting channel unit array includes a frequency multiplier, an amplifier, a filter, a millimeter-wave power divider network, an amplifier array, an adjustable attenuator array, and a phase shifter array connected in sequence. The amplifiers, adjustable attenuators, and phase shifters in the amplifier array, adjustable attenuator array, and phase shifter array are connected in a one-to-one correspondence. The local oscillator phase-shifting channel unit array includes multiple signal outputs, that is, one local oscillator phase-shifting channel unit can provide multiple local oscillator signals. The frequency multiplier (frequency multiplier + power amplifier + filter) is divided into multiple paths by the millimeter-wave power divider. Each path is fed into a single-path drive amplifier, an adjustable attenuator (which can be omitted when appropriate), and a phase shifter, thereby providing local oscillator for the terahertz frequency converter unit. Therefore, the output of the phase shifter array is connected to the mixer of the corresponding terahertz frequency converter unit.

[0039] The entire terahertz phased array system contains multiple unit modules such as phase shifters, adjustable attenuators, and switching devices. To ensure coordinated operation of the entire system, the system amplitude and phase synchronization control unit is essential. The system amplitude and phase synchronization control unit mainly performs the following tasks: ① Time-division control: selecting the switching devices in the terahertz unit and intermediate frequency unit at appropriate time intervals to select the transmit / receive channel, meeting the system's time-division transmission and reception requirements; ② Controlling the phase shifters of the intermediate frequency amplitude and phase control unit. The system adopts a high-intermediate frequency mode; the phase shifters of the intermediate frequency amplitude and phase control unit perform coarse phase adjustment, while those of the intermediate frequency amplitude and phase control unit perform precise phase adjustment; ③ Controlling the attenuators in each channel of the intermediate frequency amplitude and phase control unit to perform system linear amplitude modulation, and beam control together with phase adjustment.

Claims

1. A radio frequency architecture for a terahertz active phased array, characterized in that, The architecture includes: a baseband digital system, an intermediate frequency unit, a microwave unit, and a terahertz unit; The baseband digital system includes a baseband transmitter, a signal processing unit, and a baseband receiver connected in sequence, as well as a system amplitude and phase synchronization control unit; The intermediate frequency unit includes an intermediate frequency synthesis network, an intermediate frequency transceiver array, and an intermediate frequency amplitude and phase control unit array connected in sequence; wherein the intermediate frequency transceivers in the intermediate frequency transceiver array and the intermediate frequency amplitude and phase control units in the intermediate frequency amplitude and phase control unit array are connected in a one-to-one correspondence; The microwave unit includes a frequency synthesizer unit and a local oscillator frequency doubling channel unit connected in sequence; The terahertz unit includes a local oscillator feed network, a local oscillator phase-shifting channel unit array, and a terahertz frequency conversion unit array connected in sequence, wherein the local oscillator phase-shifting channel unit in the local oscillator phase-shifting channel unit array is connected to the terahertz frequency conversion unit in the terahertz frequency conversion unit array in a one-to-one correspondence. The baseband transmitter and baseband receiver are connected to an intermediate frequency synthesis network; The frequency amplitude phase control unit in the intermediate frequency amplitude phase control unit array is connected one-to-one with the terahertz frequency conversion unit in the terahertz frequency conversion unit array. The local oscillator frequency doubling channel unit is connected to the local oscillator feed network; The system amplitude and phase synchronization control unit is connected to each terahertz frequency converter and the intermediate frequency amplitude and phase control unit.

2. The radio frequency architecture of the terahertz active phased array according to claim 1, characterized in that, The terahertz frequency conversion unit includes a mixer, a first terahertz switching switch, a medium power amplifier, a low noise amplifier, and a second terahertz switching switch; the medium power amplifier and the low noise amplifier are connected in parallel between the first terahertz switching switch and the second terahertz switching switch, the other end of the first terahertz switching switch is connected to the mixer, and the other end of the second terahertz switching switch is connected to the antenna.

3. The radio frequency architecture of the terahertz active phased array according to claim 1, characterized in that, The intermediate frequency amplitude and phase control unit includes a millimeter-wave switching switch, an adjustable attenuator, a phase shifter, an amplifier, and a low-noise amplifier. The adjustable attenuator, phase shifter, and amplifier form an up-conversion channel, and the adjustable attenuator, phase shifter, and low-noise amplifier form a down-conversion channel. The up-conversion channel and the down-conversion channel are arranged in parallel between two millimeter-wave switching switches. The other end of the first millimeter-wave switching switch is connected to the corresponding intermediate frequency transceiver, and the other end of the second millimeter-wave switching switch is connected to the mixer of the corresponding terahertz frequency conversion unit.

4. The radio frequency architecture of the terahertz active phased array according to claim 1, characterized in that, The local oscillator phase-shifting channel unit includes a frequency multiplier, an amplifier, a filter, a millimeter-wave power divider network, an amplifier array, an adjustable attenuator array, and a phase shifter array connected in sequence. The amplifiers, adjustable attenuators, and phase shifters in the amplifier array, adjustable attenuator array, and phase shifter array are connected in a one-to-one correspondence in sequence. The outputs of the phase shifter array are all connected to the mixers of the corresponding terahertz frequency conversion units.

5. The radio frequency architecture of the terahertz active phased array according to claim 3, characterized in that, The connection order of the adjustable attenuator, phase shifter and amplifier in the upconversion channel can be adjusted according to the actual situation.

6. The radio frequency architecture of the terahertz active phased array according to claim 3, characterized in that, The millimeter-wave switching switch can be replaced with a millimeter-wave circulator.

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