Terahertz wave signal transmission method and system based on superheterodyne structure

Abstract

The invention discloses a terahertz wave signal transmission method and system based on a superheterodyne structure in the technical field of millimeter wave and terahertz wireless communication, and the method comprises a processing method of a transmitted signal and a processing method of a received signal. The transmitting signal processing method comprises the following steps: converting a baseband signal into a plurality of sub-intermediate-frequency signals through a plurality of intermediate-frequency sub-modules in an intermediate-frequency module; synthesizing the plurality of sub-intermediate-frequency signals into a broadband intermediate-frequency signal by using a power combiner, and feeding the broadband intermediate-frequency signal into a radio frequency module; the radio frequency module converts the broadband intermediate frequency signal into a terahertz wave radio frequency signal; the received signal processing method comprises the following steps: the radio frequency module converts a received terahertz wave radio frequency signal into a broadband intermediate frequency signal; dividing the broadband intermediate-frequency signal into a plurality of sub-intermediate-frequency signals by using a power divider; and respectively restoring the sub-intermediate-frequency signals into baseband signals through a plurality of intermediate-frequency sub-modules in the intermediate-frequency module. By optimizing the frequency synthesis and distribution of the signals, the transmission rate and the system capacity of the terahertz wave signals are improved.

Description

Technical Field

[0001] The invention relates to a terahertz wave signal transmission method and system based on a superheterodyne structure, belonging to the technical field of millimeter wave and terahertz wireless communication. Background Art

[0002] With the continuous development of science and technology and the continuous progress of society, the rapid development of wireless communication technology has brought about tremendous changes in people's lives. Terahertz waves are electromagnetic waves in the frequency band of 0.1~10THz, corresponding to a wavelength of 3~0.3mm, which is between millimeter waves and infrared light. The terahertz band has rich spectrum resources, the terahertz beam is narrower, the directionality is better, and the terahertz wave has better confidentiality and anti-interference ability. It can be used for short-distance high-speed wireless communication on the ground and space satellite communication, and is considered to be one of the candidate frequency bands for 6G. The millimeter wave band usually refers to 30GHz~300GHz. Millimeter waves also belong to the extremely high frequency band and have very rich spectrum resources. Compared with traditional radio frequency bands, they have a wider instantaneous bandwidth. Therefore, wireless communication technology in the field of terahertz waves and millimeter waves can provide a larger bandwidth, carry more information and have an extremely high information transmission rate.

[0003] The superheterodyne transceiver structure is a design architecture widely used in wireless communications. Its main feature is that after receiving the terahertz wave RF signal, it is first converted to an intermediate frequency, and then converted to baseband through the intermediate frequency. The intermediate frequency frequency is selected to be a frequency between the RF and the baseband. The IF in the medium frequency range can use a sharper cutoff filter to improve selectivity, and the application of the IF amplifier can obtain a higher intermediate frequency gain, which can well control the gain index of the transceiver. In the millimeter wave and terahertz fields, two-stage down-conversion and up-conversion are often required to avoid problems caused by the stability of the local oscillator. Therefore, superheterodyne receivers in the millimeter wave and terahertz fields use two local oscillators and two mixers to achieve down-conversion and up-conversion to baseband, corresponding to the symmetry of the transmitter and the receiver. Therefore, the superheterodyne transceiver system can be divided into three modules according to frequency, namely, the RF module, the intermediate frequency module, and the baseband module.

[0004] With the outbreak of the information age, the amount of information and the transmission rate have become a new industrial revolution in the field of communications. The development from 4G to 5G has transformed contemporary society from simple picture transmission to current video transmission. The current video calls, the development of short video self-media, the birth of the live broadcast industry, etc. are all based on the fifth generation of communications that carry more information and higher transmission rates. However, with the increasing demand for information, the current communication signal frequency and signal bandwidth carry a limited amount of information, and the transmission rate is also limited. Therefore, higher-frequency millimeter waves and terahertz bands have the characteristics of large instantaneous bandwidth, good anti-interference performance, small design device size, and fast transmission rate. Therefore, the development of higher-frequency transceiver signal circuits plays a vital role in the next generation of communication technology. Terahertz and millimeter wave bands, due to the extremely high signal frequency, the spectrum resources are also more abundant, and the high frequency corresponding to the modulated signal carries more information.

[0005] However, in the high-frequency millimeter wave, especially the terahertz frequency band, there are many technical challenges in designing wireless communication links. For example, due to the short wavelength, high-frequency terahertz waves are prone to parasitic effects in the circuit, easy to generate radiation, and high signal loss in the transmission path. It is difficult to directly process terahertz frequency band signals, and they are often up-converted to baseband for processing. In addition, due to the large span from the terahertz frequency band to the baseband frequency, a double up-conversion transceiver with a superheterodyne structure is often used to process terahertz frequency band signals, and the intermediate frequency is selected as the intermediate frequency signal. However, there is also a problem that although the first frequency conversion module where the terahertz wave is located can be designed to have a large bandwidth of tens of gigahertz or even larger, the intermediate frequency converted to it is often difficult to provide a bandwidth of tens of gigahertz level, especially in the baseband signal module. The baseband platform that supports tens of gigahertz bandwidth is not yet mature. Therefore, how to achieve efficient transmission and processing of terahertz wave signals based on the superheterodyne structure has become a key technical problem that needs to be solved in this field. Summary of the invention

[0006] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a terahertz wave signal transmission method and system based on a superheterodyne structure, which improves the transmission rate and system capacity of the terahertz wave signal by optimizing the synthesis and distribution of signals, while ensuring high-quality restoration of the receiving unit signal and reducing noise interference.

[0007] To achieve the above object, the present invention is implemented by adopting the following technical solutions:

[0008] In a first aspect, the present invention provides a terahertz wave signal transmission method based on a superheterodyne structure, including a transmission signal processing method and a reception signal processing method.

[0009] The transmission signal processing method comprises:

[0010] The baseband signal is up-converted into multiple sub-IF signals through multiple IF sub-modules in the IF module; the multiple sub-IF signals are synthesized into a broadband IF signal by a power synthesizer, and fed into the RF module; the broadband IF signal is up-converted into a terahertz wave RF signal through the RF module, and the terahertz wave RF signal is output;

[0011] The received signal processing method comprises:

[0012] The RF module down-converts the received terahertz wave RF signal into a broadband intermediate frequency signal; uses a power divider to divide the broadband intermediate frequency signal into multiple sub-intermediate frequency signals; and uses multiple intermediate frequency sub-modules in the intermediate frequency module to down-convert the sub-intermediate frequency signals and restore them to baseband signals.

[0013] Furthermore, the baseband signal is generated by the baseband module and transmitted to the intermediate frequency module; when processing the received signal, the baseband module is also used to process the baseband signal restored by the intermediate frequency module;

[0014] The terahertz wave radio frequency signal output by the radio frequency module is transmitted to the free space through the antenna module; the terahertz wave radio frequency signal in the free space is received by the antenna module and transmitted to the radio frequency module.

[0015] Furthermore, the operating frequency ranges of the power synthesizer and the power divider cover the frequency range of the radio frequency module, the power synthesizer is used to realize the synthesis of multi-channel intermediate frequency signals; the power divider is used to realize the distribution of multi-channel intermediate frequency signals.

[0016] Furthermore, the bandwidth of the intermediate frequency submodule is determined by dividing the bandwidth of the radio frequency module, and each intermediate frequency submodule after division has a uniform bandwidth, and the bandwidth of each sub-intermediate frequency signal satisfies ;

[0017] in, Indicates The bandwidth of each IF submodule; Indicates the bandwidth of the RF module; Indicates the number of IF submodules.

[0018] Furthermore, each intermediate frequency submodule corresponds to an independent baseband module, and the bandwidth of each sub-intermediate frequency module is consistent with the bandwidth m of the baseband module, and the bandwidth of each baseband module satisfies ;

[0019] Through the power combiner The sub-IF signals corresponding to the IF sub-modules are synthesized into a broadband IF signal IF, and the bandwidth of the broadband IF signal IF is equal to The sum of the bandwidths of the intermediate frequency submodules, the starting frequency of the broadband intermediate frequency signal IF and the first sub-intermediate frequency signal The starting frequency The termination frequency is consistent with the Sub-IF signal The stop frequency Consistent, the frequency range of the broadband intermediate frequency signal IF is consistent with the frequency range of the RF module Consistent.

[0020] Furthermore, the intermediate frequency module includes a bandpass filter, each of which is used to select the allocated sub-intermediate frequency signal and limit the frequency range of the sub-intermediate frequency signal to between the starting frequency and the ending frequency of the sub-intermediate frequency signal.

[0021] In a second aspect, the present invention provides a terahertz wave signal transmission system based on a superheterodyne structure, comprising:

[0022] An intermediate frequency module, comprising a plurality of intermediate frequency submodules, wherein a transmitting unit of each intermediate frequency submodule is used to up-convert a baseband signal into a plurality of sub-intermediate frequency signals, and a receiving unit is used to down-convert the sub-intermediate frequency signal into a baseband signal;

[0023] A power synthesizer, connected to the intermediate frequency module, for synthesizing a plurality of sub-intermediate frequency signals into a broadband intermediate frequency signal;

[0024] A radio frequency module, wherein the transmitting unit of the radio frequency module is connected to the power synthesizer and is used to up-convert the broadband intermediate frequency signal into a terahertz wave radio frequency signal; the receiving unit of the radio frequency module is used to down-convert the terahertz wave radio frequency signal into a broadband intermediate frequency signal;

[0025] The power distributor is connected to the receiving unit of the radio frequency module and is used to distribute the broadband intermediate frequency signal to multiple intermediate frequency sub-modules.

[0026] Furthermore, the terahertz wave signal transmission system based on the superheterodyne structure also includes a baseband module and an antenna module.

[0027] The transmitting unit of the baseband module generates a baseband signal and transmits the baseband signal to the intermediate frequency module; the receiving unit of the baseband module processes the baseband signal restored by the intermediate frequency module;

[0028] The transmitting unit of the antenna module is used to transmit the terahertz wave radio frequency signal to the free space; the receiving unit of the antenna module is used to receive the terahertz wave radio frequency signal in the free space.

[0029] Furthermore, the transmitting unit of the intermediate frequency module up-converts the baseband signal into a plurality of sub-intermediate frequency signals through step-by-step processing of a low noise amplifier, a bandpass filter, a mixer and a bandpass filter; the receiving unit of the intermediate frequency module down-converts the sub-intermediate frequency signal into a baseband signal through step-by-step processing of a bandpass filter, a mixer, a bandpass filter and a variable gain amplifier;

[0030] The transmitting unit of the radio frequency module up-converts the broadband intermediate frequency signal into a terahertz wave radio frequency signal through the step-by-step processing of a low noise amplifier, a mixer, a power amplifier, a bandpass filter and a power amplifier; the receiving unit of the radio frequency module down-converts the terahertz wave radio frequency signal into a broadband intermediate frequency signal through the step-by-step processing of a low noise amplifier, a bandpass filter, a mixer and a low noise amplifier.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] The terahertz wave signal transmission method based on the superheterodyne structure provided by the present invention effectively improves the bandwidth and transmission rate of the signal by converting the baseband signal into multiple sub-intermediate frequency signals in the transmitting unit and synthesizing the broadband intermediate frequency signal using a power synthesizer. The receiving unit uses a power divider to divide the broadband intermediate frequency signal into multiple sub-intermediate frequency signals, and further restores them to the baseband signal through the intermediate frequency module. This method not only improves the bandwidth utilization, but also effectively reduces noise interference, ensures the high quality and high efficiency of signal transmission, and is suitable for terahertz communication systems with high bandwidth requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is a schematic block diagram of a terahertz wave signal transmission method based on a superheterodyne structure provided in the first embodiment of the present invention;

[0034] Figure 2 1 is a schematic diagram of the architecture of a superheterodyne double up-conversion transceiver provided in Embodiment 1 of the present invention;

[0035] Figure 3 It is a schematic block diagram of the mirror frequency principle in the superheterodyne structure provided in the first embodiment of the present invention. DETAILED DESCRIPTION

[0036] The technical solution of the present invention is described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical solution of the present application, rather than limitations on the technical solution of the present application. In the absence of conflict, the embodiments of the present application and the technical features in the embodiments can be combined with each other.

[0037] Embodiment 1:

[0038] Figure 1This is a schematic block diagram of a terahertz wave signal transmission method based on a superheterodyne structure in Embodiment 1 of the present invention. This schematic block diagram only shows the logical sequence of the method described in this embodiment. In other possible embodiments of the present invention, different Figure 1 The steps shown or described are accomplished in the order shown.

[0039] See also Figure 1 The method of this implementation specifically includes the following steps:

[0040] The transmission signal processing method comprises:

[0041] The baseband signal is up-converted into multiple sub-IF signals through multiple IF sub-modules in the IF module; the multiple sub-IF signals are synthesized into a broadband IF signal by a power synthesizer, and fed into the RF module; the broadband IF signal is up-converted into a terahertz wave RF signal through the RF module, and the terahertz wave RF signal is output;

[0042] The received signal processing method comprises:

[0043] The RF module down-converts the received terahertz wave RF signal into a broadband intermediate frequency signal; uses a power divider to divide the broadband intermediate frequency signal into multiple sub-intermediate frequency signals; and uses multiple intermediate frequency sub-modules in the intermediate frequency module to down-convert the sub-intermediate frequency signals and restore them to baseband signals.

[0044] like Figure 1 As shown, the signal transmitting unit and receiving unit present a symmetrical structure, both of which have a baseband module, an intermediate frequency module and an RF module. Since the terahertz band has an extremely high frequency, the instantaneous bandwidth in the terahertz band is relatively wide, and it can carry a large amount of data while having an extremely high transmission rate. The use of a superheterodyne structured transceiver to process the terahertz band can reduce the extremely high frequency terahertz wave to a relatively low frequency band for further processing, which can reduce the difficulty of design and better handle some crosstalk. However, the problem is that the RF module can be designed as a module that supports a large bandwidth, so that it has an extremely high data transmission capability in the terahertz frequency band. However, during the signal transmission process, the terahertz wave RF signal needs to be converted into an intermediate frequency signal through an intermediate frequency module, and then further converted into a baseband signal. Due to the limited circuit design of the intermediate frequency module, it is usually difficult to achieve the same ultra-wideband capability as the RF module. Therefore, when selecting an intermediate frequency signal, its bandwidth is usually much smaller than the bandwidth of the RF module, resulting in the signal being limited by bandwidth matching during transmission.

[0045] In addition, the bandwidth of the baseband signal is also much smaller than that of the RF module. As the starting point and end point of signal processing, the bandwidth of the baseband module is usually smaller than that of the intermediate frequency module, and the bandwidth of the intermediate frequency module is smaller than that of the RF module. This hierarchical relationship of bandwidth means that in the terahertz wave communication system, although the RF module can support ultra-wideband signal transmission, the bandwidth utilization of the overall system is affected due to the bandwidth limitations of the intermediate frequency and baseband modules. Therefore, in the present invention, the bandwidth matching efficiency of each module in the superheterodyne structure is improved through reasonable signal allocation and frequency planning to optimize the signal transmission performance. The specific process is as follows:

[0046] Baseband signal is represented by Baseband, and intermediate frequency sub-signals are represented by The terahertz wave radio frequency signal is represented by RF (Radio Frequency). Each baseband module has the same bandwidth, represented by m. The bandwidth of the RF module is represented by M, and the bandwidth of each submodule in the intermediate frequency module is represented by express.

[0047] In the transmitting unit, first, the baseband signal is transmitted through the intermediate frequency module The intermediate frequency submodules are up-converted into Sub-IF signal The bandwidth of each IF submodule is determined by dividing the bandwidth of the RF module. After division, each IF submodule has a uniform bandwidth, satisfying This division ensures that the large bandwidth signal of the RF module can be decomposed into multiple narrowband signals for easy processing.

[0048] During the frequency planning process, the sub-IF signal The frequency range of is determined by its start and end frequencies, for example : , : , and so on, until : These sub-IF signals are synthesized into a broadband IF signal IF through a power synthesizer. The synthesized broadband IF signal IF has the following characteristics:

[0049] 1. The total bandwidth of the synthetic signal is M, that is ;

[0050] 2. The starting frequency of the synthetic signal and The starting frequency Consistency;

[0051] 3. The end frequency of the synthetic signal and The stop frequency Consistent.

[0052] Subsequently, the broadband intermediate frequency signal IF is transmitted to the RF module, where it is up-converted into a terahertz wave RF signal RF, and the terahertz wave RF signal is transmitted into free space through the antenna module. This method achieves broadband consistent transmission from baseband to RF by dividing and synthesizing multiple signals, effectively improving the system's signal processing capability and data carrying capacity.

[0053] In the receiving unit, the signal is processed in a symmetrical way with the transmitting unit. The receiving unit of the antenna module receives the terahertz wave radio frequency signal RF from free space and transmits it to the radio frequency module. In the radio frequency module, the terahertz wave radio frequency signal RF is down-converted into a broadband intermediate frequency signal IF. At this time, the bandwidth of the terahertz wave radio frequency signal RF and the broadband intermediate frequency signal IF are both M, maintaining the bandwidth consistency of the system.

[0054] Then, the broadband intermediate frequency signal IF is decomposed into n intermediate frequency signals through a power divider. Each intermediate frequency signal has a specific frequency range, which is determined by the starting frequency and the ending frequency. : , : , , : The power divider ensures that the bandwidth of the decomposed sub-IF signals remains uniform. The bandwidth of each sub-IF signal is , total bandwidth It is consistent with the bandwidth of the input wideband intermediate frequency signal IF.

[0055] The bandpass filter in the IF module has a gating function, which can accurately filter the frequency range signal corresponding to each IF sub-module to avoid frequency band overlap or interference. The gated sub-IF signal is further down-converted into a baseband signal Baseband in the IF module, and its bandwidth is consistent with the baseband signal bandwidth m of the transmitting unit, ensuring the integrity and consistency of signal transmission.

[0056] Each intermediate frequency submodule corresponds to a baseband module one by one. The signal processed by each intermediate frequency submodule is restored through a separate baseband module. The structure and parameters of all baseband modules remain consistent, ensuring that the final output baseband signal completely restores the original signal of the transmitting unit. Through this method, the receiving unit realizes efficient frequency conversion processing of terahertz wave RF signals from high frequency to low frequency, making full use of the large bandwidth characteristics of the system while ensuring signal integrity and data carrying capacity.

[0057] In this embodiment, the terahertz wave radio frequency signal is transmitted and received based on the superheterodyne structure. The signal processing process includes multiple modules of the transmitting unit and the receiving unit, combined with Figure 2The superheterodyne double-conversion transceiver architecture shown in the figure is used to perform a detailed description of the terahertz wave RF signal transmission and reception process as follows:

[0058] In the transmitting unit, each intermediate frequency sub-module in the intermediate frequency module is processed step by step by a low noise amplifier, a bandpass filter, a mixer and a bandpass filter to up-convert each baseband signal generated by the baseband module into each sub-intermediate frequency signal. Specifically, the baseband signal is initially amplified by a low noise amplifier and then filtered by a bandpass filter to remove unnecessary frequency components. Next, the mixer mixes the baseband signal with the local oscillator signal to generate a sub-intermediate frequency signal, and then further filters the signal output by the mixer through a bandpass filter to remove useless frequency components (such as image frequencies) generated during the mixing process, retaining only the target sub-intermediate frequency signal. Each sub-intermediate frequency signal is synthesized into a broadband intermediate frequency signal by a power synthesizer, and then the broadband intermediate frequency signal is sent to the RF module for processing.

[0059] In the RF module, the broadband intermediate frequency signal is amplified by a low-noise amplifier and then mixed with the local oscillator signal through a mixer to generate a terahertz wave RF signal. The terahertz wave RF signal is further enhanced by a power amplifier and filtered out unnecessary frequency bands through a bandpass filter. Finally, the power is increased by a power amplifier and the terahertz wave RF signal is transmitted into free space through an antenna module.

[0060] In the receiving unit, the receiving unit uses a symmetrical method with the transmitting unit to receive the terahertz wave RF signal. First, the terahertz wave RF signal from the free space is received by the antenna module and transmitted to the RF module. According to the cascade noise coefficient formula It can be seen that the overall cascade noise coefficient is mainly related to the previous stage. In order to reduce the impact of noise, the RF module first significantly reduces the noise through a low-noise amplifier. The low-noise amplifier in the RF module amplifies the weak terahertz wave RF signal and filters the signal through a bandpass filter. Since the superheterodyne structure will have image frequency interference, the image frequency signal will be mixed with the received terahertz wave RF signal after mixing, so it is necessary to add a bandpass filter before the mixer to filter out these image frequency signals to avoid interference. Figure 3 This is a schematic diagram of the mirror frequency principle in the superheterodyne structure, showing how the signal is filtered to remove interference signals after mixing. Next, the mixer mixes the terahertz wave RF signal with the local oscillator signal, and the frequency of the terahertz wave RF signal is reduced to the broadband intermediate frequency range. The mixed signal contains some useless frequency components, so it passes through a low-noise amplifier again, which further amplifies the signal while suppressing the introduction of noise to ensure that the purity and strength of the signal meet the requirements of subsequent processing. Through the above steps, the terahertz wave RF signal is gradually down-converted to a broadband intermediate frequency signal.

[0061] The broadband intermediate frequency signal is divided into sub-intermediate frequency signals through a power divider. The intermediate frequency module first processes the sub-intermediate frequency signal through a bandpass filter to remove unnecessary frequency components in the signal and retain only the signal within a specific frequency band to reduce noise and interference. Next, the signal enters the mixer and mixes with the local oscillator signal to achieve frequency down-conversion, reducing the frequency of the signal from the sub-intermediate frequency to a lower frequency close to the baseband frequency. The mixed signal passes through a bandpass filter again to further filter out the useless frequency components generated during the mixing process, such as the image frequency and mixing products, to ensure that only signals within the target frequency range pass. Finally, the signal enters the variable gain amplifier, which dynamically adjusts the gain according to the strength of the signal to ensure that the amplitude of the output signal is within a suitable range to meet the needs of the subsequent processing circuit and ensure the stability and quality of the signal. Through the above steps, the sub-intermediate frequency signal is gradually down-converted and restored to the baseband signal, ready for subsequent demodulation and processing.

[0062] In the superheterodyne double up-conversion structure of the present invention, the frequency conversion of the signal depends on two local oscillator signals, namely Figure 2 The local oscillator signal 1 and the local oscillator signal 2 are shown. The local oscillator signal is a stable high-frequency signal, which is used to up-convert the baseband signal to the intermediate frequency signal and up-convert the intermediate frequency signal to the radio frequency signal in the transmitting unit; or down-convert the terahertz wave radio frequency signal to the intermediate frequency signal and down-convert the intermediate frequency signal to the baseband signal in the receiving unit. In order to generate a stable and accurate local oscillator signal, the present invention adopts a local oscillator phase-locked loop as a signal source. During the design, the phase-locked loop module needs to meet the driving power requirements of the mixer to ensure the efficiency and signal quality of the mixing process. At the same time, in order to avoid signal distortion caused by frequency drift or phase noise, the phase-locked loop design needs to ensure that the output signal has good frequency stability and low phase noise. In the present invention, the phase-locked loop module realizes different local oscillator frequencies by adjusting the division ratio to meet the needs of multi-band signal processing. In addition, its output power needs to match the mixer, which should not be too low to avoid reducing the mixing efficiency, nor too high to avoid introducing nonlinear distortion. This design ensures the efficiency and reliability of the signal during the frequency conversion process.

[0063] Through the structural design and signal processing process of the transmitting unit and the receiving unit, this embodiment realizes efficient terahertz wave signal transmission, ensuring the quality and data carrying capacity of the terahertz wave signal in the entire communication link.

[0064] Embodiment 2:

[0065] This embodiment provides a terahertz wave signal transmission system based on a superheterodyne structure, including:

[0066] An intermediate frequency module, comprising a plurality of intermediate frequency submodules, wherein a transmitting unit of each intermediate frequency submodule is used to up-convert a baseband signal into a plurality of sub-intermediate frequency signals, and a receiving unit is used to down-convert the sub-intermediate frequency signal into a baseband signal;

[0067] A power synthesizer, connected to the intermediate frequency module, for synthesizing a plurality of sub-intermediate frequency signals into a broadband intermediate frequency signal;

[0068] A radio frequency module, wherein the transmitting unit of the radio frequency module is connected to the power synthesizer and is used to up-convert the broadband intermediate frequency signal into a terahertz wave radio frequency signal; the receiving unit of the radio frequency module is used to down-convert the terahertz wave radio frequency signal into a broadband intermediate frequency signal;

[0069] The power distributor is connected to the receiving unit of the radio frequency module and is used to distribute the broadband intermediate frequency signal to multiple intermediate frequency sub-modules.

[0070] The terahertz wave signal transmission system based on the superheterodyne structure also includes a baseband module and an antenna module. The transmitting unit of the baseband module generates a baseband signal and transmits the baseband signal to the intermediate frequency module; the receiving unit of the baseband module processes the baseband signal restored by the intermediate frequency module;

[0071] The transmitting unit of the antenna module is used to transmit the terahertz wave radio frequency signal to the free space; the receiving unit of the antenna module is used to receive the terahertz wave radio frequency signal in the free space.

[0072] The transmitting unit of the intermediate frequency module up-converts the baseband signal into multiple sub-intermediate frequency signals through step-by-step processing of a low noise amplifier, a bandpass filter, a mixer and a bandpass filter; the receiving unit of the intermediate frequency module down-converts the sub-intermediate frequency signal into a baseband signal through step-by-step processing of a bandpass filter, a mixer, a bandpass filter and a variable gain amplifier;

[0073] The transmitting unit of the radio frequency module up-converts the broadband intermediate frequency signal into a terahertz wave radio frequency signal through the step-by-step processing of a low noise amplifier, a mixer, a power amplifier, a bandpass filter and a power amplifier; the receiving unit of the radio frequency module down-converts the terahertz wave radio frequency signal into a broadband intermediate frequency signal through the step-by-step processing of a low noise amplifier, a bandpass filter, a mixer and a low noise amplifier.

[0074] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A terahertz wave signal transmission method based on a superheterodyne structure, characterized in that: It includes a transmission signal processing method and a reception signal processing method, The transmission signal processing method comprises: The baseband signal is up-converted into multiple sub-IF signals through multiple IF sub-modules in the IF module; the multiple sub-IF signals are synthesized into a broadband IF signal by a power synthesizer, and fed into the RF module; the broadband IF signal is up-converted into a terahertz wave RF signal through the RF module, and the terahertz wave RF signal is output; The received signal processing method comprises: The RF module down-converts the received terahertz wave RF signal into a broadband intermediate frequency signal; uses a power divider to divide the broadband intermediate frequency signal into multiple sub-intermediate frequency signals; and uses multiple intermediate frequency sub-modules in the intermediate frequency module to down-convert the sub-intermediate frequency signals and restore them to baseband signals.

2. The terahertz wave signal transmission method based on a superheterodyne structure according to claim 1, characterized in that: The baseband signal is generated by the baseband module and transmitted to the intermediate frequency module; when processing the received signal, the baseband module is also used to process the baseband signal restored by the intermediate frequency module; The terahertz wave radio frequency signal output by the radio frequency module is transmitted to the free space through the antenna module; the terahertz wave radio frequency signal in the free space is received by the antenna module and transmitted to the radio frequency module.

3. The terahertz wave signal transmission method based on a superheterodyne structure according to claim 1, characterized in that: The operating frequency ranges of the power synthesizer and the power divider cover the frequency range of the radio frequency module. The power synthesizer is used to realize the synthesis of multi-channel intermediate frequency signals; the power divider is used to realize the distribution of multi-channel intermediate frequency signals.

4. The terahertz wave signal transmission method based on a superheterodyne structure according to claim 1, characterized in that: The bandwidth of the intermediate frequency submodule is determined by dividing the bandwidth of the radio frequency module. The intermediate frequency submodules after division have uniform bandwidth, and the bandwidth of each sub-intermediate frequency signal satisfies ; in, Indicates The bandwidth of the IF submodule; Indicates the bandwidth of the RF module; Indicates the number of IF submodules.

5. The terahertz wave signal transmission method based on a superheterodyne structure according to claim 4, characterized in that: Each IF submodule corresponds to an independent baseband module. The bandwidth of each sub-IF module is consistent with the bandwidth m of the baseband module. The bandwidth of each baseband module satisfies ; Through the power combiner The sub-IF signals corresponding to the IF sub-modules are synthesized into a broadband IF signal IF, and the bandwidth of the broadband IF signal IF is equal to The sum of the bandwidths of the intermediate frequency submodules, the starting frequency of the broadband intermediate frequency signal IF and the first sub-intermediate frequency signal The starting frequency The termination frequency is consistent with the Sub-IF signal The stop frequency Consistent, the frequency range of the broadband intermediate frequency signal IF is consistent with the frequency range of the RF module Consistent.

6. The terahertz wave signal transmission method based on a superheterodyne structure according to claim 1, characterized in that: The intermediate frequency module includes bandpass filters, each of which is used to select the allocated sub-intermediate frequency signal and limit the frequency range of the sub-intermediate frequency signal to between the starting frequency and the ending frequency of the sub-intermediate frequency signal.

7. A terahertz wave signal transmission system based on a superheterodyne structure, characterized in that: include: An intermediate frequency module, comprising a plurality of intermediate frequency submodules, wherein a transmitting unit of each intermediate frequency submodule is used to up-convert a baseband signal into a plurality of sub-intermediate frequency signals, and a receiving unit is used to down-convert the sub-intermediate frequency signal into a baseband signal; A power synthesizer, connected to the intermediate frequency module, for synthesizing a plurality of sub-intermediate frequency signals into a broadband intermediate frequency signal; A radio frequency module, wherein the transmitting unit of the radio frequency module is connected to the power synthesizer and is used to up-convert the broadband intermediate frequency signal into a terahertz wave radio frequency signal; the receiving unit of the radio frequency module is used to down-convert the terahertz wave radio frequency signal into a broadband intermediate frequency signal; The power distributor is connected to the receiving unit of the radio frequency module and is used to distribute the broadband intermediate frequency signal to multiple intermediate frequency sub-modules.

8. The terahertz wave signal transmission system based on a superheterodyne structure according to claim 7, characterized in that: It also includes baseband module and antenna module. The transmitting unit of the baseband module generates a baseband signal and transmits the baseband signal to the intermediate frequency module; the receiving unit of the baseband module processes the baseband signal restored by the intermediate frequency module; The transmitting unit of the antenna module is used to transmit the terahertz wave radio frequency signal to the free space; the receiving unit of the antenna module is used to receive the terahertz wave radio frequency signal in the free space.

9. The terahertz wave signal transmission system based on a superheterodyne structure according to claim 7, characterized in that: The transmitting unit of the intermediate frequency module up-converts the baseband signal into multiple sub-intermediate frequency signals through step-by-step processing of a low noise amplifier, a bandpass filter, a mixer and a bandpass filter; the receiving unit of the intermediate frequency module down-converts the sub-intermediate frequency signal into a baseband signal through step-by-step processing of a bandpass filter, a mixer, a bandpass filter and a variable gain amplifier; The transmitting unit of the radio frequency module up-converts the broadband intermediate frequency signal into a terahertz wave radio frequency signal through the step-by-step processing of a low noise amplifier, a mixer, a power amplifier, a bandpass filter and a power amplifier; the receiving unit of the radio frequency module down-converts the terahertz wave radio frequency signal into a broadband intermediate frequency signal through the step-by-step processing of a low noise amplifier, a bandpass filter, a mixer and a low noise amplifier.

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