Vector network analyzer frequency expander, system and measurement method

Abstract

The invention relates to a vector network analyzer frequency expander, system and measurement method, and the system comprises an ultra-wideband switch which is provided with a control port, a common port, a first channel port and a second channel port; the input end of the first bi-directional coupler is used for receiving a first low-frequency-band radio frequency signal from the vector network analyzer host, and the straight-through end of the first bi-directional coupler is connected to the first channel port of the switch; and the input end of the high-frequency spread spectrum module is used for receiving a second low-frequency-band radio frequency signal from the vector network analyzer host, and the output end of the high-frequency spread spectrum module is connected to the second channel port of the ultra-wideband switch. According to the frequency expander, the 67-110 GHz spread spectrum module and the 10 MHz-110 GHz switch are integrated, broadband coverage from 10 MHz to 110 GHz is achieved, a network analyzer host can support S parameter testing in an ultra-wide frequency range, and the testing frequency range and the application scene are remarkably expanded.

Description

Technical Field

[0001] This invention relates to the field of microwave and radio frequency engineering technology, and in particular to a vector network analyzer frequency extender, system, and measurement method. Background Technology

[0002] A vector network analyzer is a core test instrument used to measure the energy characteristics of electromagnetic waves. It can measure not only the amplitude information of network parameters (such as S-parameters) but also their precise phase information. Its basic working principle is based on an internal precision signal source that excites the device under test (DUT) by scanning a frequency band. In single-port measurements, the vector network analyzer accurately characterizes the impedance or reflection characteristics of the DUT, such as return loss, by measuring the amplitude and phase of the signal reflected from the port. In two-port and higher-port measurements, it can comprehensively evaluate transmission characteristics such as insertion loss, gain, and phase delay. Therefore, the vector network analyzer has become an indispensable tool in the research, development, manufacturing, and maintenance of components, circuits, and systems in the RF, microwave, and millimeter-wave fields.

[0003] Currently, with the rapid development of wireless communication, radar, aerospace and semiconductor technologies, the operating frequency of devices under test is constantly expanding to the millimeter wave and even terahertz bands, which puts forward increasingly higher requirements for the test frequency range of vector network analyzers.

[0004] In view of the above-mentioned shortcomings, the designer has actively researched and innovated in order to create a vector network analyzer frequency extender, system and measurement method, which will make it more industrially valuable. Summary of the Invention

[0005] To address the aforementioned technical problems, the present invention aims to provide a vector network analyzer frequency extender, system, and measurement method.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: One of the objectives of this invention is: A vector network analyzer frequency extender, comprising: An ultra-wideband switch has a control port, a common port, a first channel port and a second channel port. The control port is controlled by a test controller, and the common port serves as the test port for a frequency extender. A first dual directional coupler, the input of which is used to receive a first low-frequency radio frequency signal from the vector network analyzer host, and its through-end is connected to the first channel port of the switch; A high-frequency spread spectrum module, whose input is used to receive a second low-frequency radio frequency signal from the host of a vector network analyzer, and whose output is connected to the second channel port of an ultra-wideband switch; The ultra-wideband switch is configured such that: the control port is used for signal selection; in the transmission path, the low-frequency signal of the first channel port and the high-frequency signal of the second channel port are sequentially switched to the common port output; in the reception path, the signal received by its common port is sequentially directed to the first channel port and the second channel port.

[0007] As a further improvement of this invention, the frequency switching point of the ultra-wideband switch coincides with the maximum native output frequency of the vector network analyzer host. The low-frequency band covers a continuous frequency band from the lowest frequency of the vector network analyzer host to the frequency switching point, and the high-frequency band covers a continuous frequency band from the frequency switching point to the maximum extended frequency of the high-frequency spread spectrum module. Within the extreme wideband of 10MHz-100GHz, the ultra-wideband switch significantly improves the full-band insertion loss flatness and high-frequency isolation by employing a topology combining distributed compensation circuitry and multi-level isolation structures. Simultaneously, by combining three-dimensional heterogeneous integrated packaging and low-power latch drive technology, it achieves chip-level miniaturization while simultaneously ensuring high power capacity, fast switching speed, and low static power consumption.

[0008] As a further improvement of the present invention, the high-frequency spread spectrum module includes: A transmit link is used to multiply the input second low-frequency radio frequency signal to generate a high-frequency excitation signal; the transmit link includes at least a first frequency multiplier and an isolator connected in sequence. A built-in second dual directional coupler, coupled to the output of the transmit link, is used to extract the high-frequency incident signal input to the device under test and the high-frequency reflected signal from the device under test; At least one mixer receiving link is used to receive the signal extracted by the built-in second dual directional coupler and mix it with a high-frequency local oscillator signal. After down-conversion, the reference intermediate frequency signal and the measurement intermediate frequency signal are output.

[0009] As a further improvement of the present invention, the high-frequency spread spectrum module also includes a single-vibrator power divider and two-channel mixer receiving links; The local oscillator power divider is used to split one high-frequency local oscillator signal into two; One of the mixing receiver links serves as a reference channel, which includes a second frequency multiplier and a first frequency mixer connected in sequence. The first mixer is used to mix the frequency-multiplied local oscillator signal with the incident signal extracted by the second dual directional coupler and output a reference intermediate frequency signal. Another mixing receiver link serves as a measurement channel, which includes a third frequency multiplier, a second frequency mixer, and an intermediate frequency power amplifier connected in sequence. The second frequency mixer is used to mix the frequency-multiplied local oscillator signal with the reflected or transmitted signal extracted by the second dual directional coupler to output the measurement intermediate frequency signal.

[0010] As a further improvement of the present invention, in the mixing receiver link of the measurement channel, the power amplifier connected in series after the second mixer is an adjustable gain power amplifier.

[0011] As a further improvement of the present invention, a first dual-directional coupler connected to the first channel port of the ultra-wideband switch outputs a reference signal for characterizing the energy of the incident wave and a measurement signal for characterizing the energy of the reflected wave or the transmitted wave, respectively.

[0012] As a further improvement of the present invention, the ultra-wideband switch, the first dual directional coupler, and the high-frequency spread spectrum module are integrated and packaged in a unified shielded housing.

[0013] The second objective of this invention is: A frequency extension system for a vector network analyzer, comprising: A vector network analyzer host is used to generate a first low-frequency band RF signal and a second low-frequency band RF signal; A frequency extender as described above has its first input port connected to the host of a vector network analyzer to receive a first low-frequency radio frequency signal, and its second input port connected to the host of the vector network analyzer to receive a second low-frequency radio frequency signal. The test port of the frequency extender is used to output a continuous spectrum excitation signal covering the frequency range from the lower limit of the first low-frequency band RF signal to the upper limit of the extended high-frequency band to the device under test, and to receive the full-band response signal from the device under test. The vector network analyzer host calculates the S-parameters of the device under test in the ultra-wideband based on the low-frequency band and the down-converted high-frequency band signal in the response signal.

[0014] The third objective of this invention: A continuous frequency sweep measurement method for a frequency extender as described above includes the following steps: Step 1: The vector network analyzer host generates a continuous sweep frequency signal covering its native frequency band as the first low-frequency band RF signal, and at the same time generates a single frequency point or narrowband sweep frequency signal as the second low-frequency band RF signal. Step 2: The first low-frequency band radio frequency signal is processed by the first dual directional coupler and the first channel of the ultra-wideband switch in the expander; the second low-frequency band radio frequency signal is up-converted by the high-frequency spread spectrum module and processed by the second channel of the ultra-wideband switch in the expander. Step 3: The ultra-wideband switch can generate a continuous spectrum excitation signal covering the low-frequency start point to the high-frequency cutoff point by switching its two channels, and apply it to the device under test through the test port; Step 4: The response signal from the device under test enters the ultra-wideband switch through the test port, and is switched by the switch control terminal to be introduced into the first channel port and the second channel port in sequence; Step 5: The low-frequency response signal is sampled by the first dual directional coupler to obtain the reference signal and the measurement signal, which are then directly returned to the vector network analyzer host; the high-frequency response signal is down-converted into the reference intermediate frequency signal and the measurement intermediate frequency signal in the high-frequency spread spectrum module and then returned to the vector network analyzer host. Step 6: The vector network analyzer host processes the two received signals sequentially, calculates and synthesizes the S-parameter curves of the device under test throughout the entire ultra-wideband.

[0015] By means of the above-described solution, the present invention has at least the following advantages: The frequency extender of this invention achieves wide bandwidth coverage from 10MHz to 110GHz by integrating a 67GHz-110GHz spread spectrum module and a 10MHz-110GHz switch, enabling the network analyzer host to support S-parameter testing over an ultra-wide frequency range, significantly expanding the test frequency range and application scenarios.

[0016] This invention integrates the spread spectrum module and the switch into one unit. The frequency extender has a compact structure, which effectively reduces the size of the device, making it easy to carry and integrate into existing test systems, while improving the overall stability and reliability of the system.

[0017] The frequency extender design of this invention can be directly used with a 10MHz-67GHz network analyzer host without complex modifications or additional configurations, achieving efficient expansion of existing test systems and reducing upgrade costs and operational complexity.

[0018] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the following are preferred embodiments of the present invention described in detail with reference to the accompanying drawings. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the structure of a frequency extender for a vector network analyzer according to the present invention; Figure 2 yes Figure 1 A schematic diagram of the spread spectrum module.

[0021] The meanings of the labels in the figures are as follows.

[0022] 1. First dual directional coupler; 2. High-frequency spread spectrum module; 3. Ultra-wideband switch; 4. First frequency multiplier; 5. Isolator; 6. Second dual directional coupler; 7. Local oscillator power divider; 8. Second frequency multiplier; 9. First mixer; 10. Third frequency multiplier; 11. Second mixer; 12. Power amplifier. Detailed Implementation

[0023] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0024] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0025] First embodiment of the present invention: like Figures 1-2 As shown, a vector network analyzer frequency extender according to this embodiment includes: An ultra-wideband switch 3 has a control port, a common port, a first channel port and a second channel port. The control port is controlled by a test controller, and the common port serves as the test port for the frequency extender. A first dual directional coupler 1, the input of which is used to receive a first low-frequency radio frequency signal RF1 from the vector network analyzer host, and the through end of which is connected to the first channel port of the ultra-wideband switch 3; A high-frequency spread spectrum module 2, whose input is used to receive a second low-frequency radio frequency signal RF2 from the vector network analyzer host, and whose output is connected to the second channel port of the ultra-wideband switch 3; The ultra-wideband switch 3 is configured such that: the control port is used for signal selection; in the transmission path, the low-frequency signal of the first channel port and the high-frequency signal of the second channel port are sequentially switched to the common port output; in the reception path, the signal received by its common port is sequentially directed to the first channel port and the second channel port.

[0026] The core protection point of this embodiment lies in the specific connection relationship and functional configuration of "ultra-wideband switch + first dual directional coupler + high-frequency spread spectrum module".

[0027] 1. Ultra-wideband switch: In the existing system, it functions as a fixed signal path selector, switching between different radio frequency channels.

[0028] In this embodiment, it is the core of the system's "frequency domain intelligent scheduler" and "multi-functional test interface". Its common port is a critical, full-band signal access point, dynamically executing the generation of excitation signals and the acquisition of response signals.

[0029] Functional Expansion and Architectural Significance: When applied to the front end of a test system, it covers extreme bandwidths (10MHz~110GHz) and serves as the core architectural cornerstone for achieving "single-port direct scan," solving the fundamental problem of providing a physically single, spectrum-continuous test port.

[0030] 2. Connect the first dual directional coupler: In the existing technology, it is a general-purpose signal sampling device in microwave testing and can be used in any link that requires sampling.

[0031] In this embodiment, a dedicated sampling channel for vector information in the native low-frequency band (such as 10MHz-67GHz) is provided. This ensures that the host performs vector sampling in the most direct and least lossy way within its native frequency band where performance is optimal.

[0032] Path exclusivity and functional purification: It is fixedly deployed before the first channel of the switch to form an independent and isolated low-frequency measurement reference channel, which ensures that the basic accuracy of the system does not deteriorate due to expansion and avoids high-frequency signal interference.

[0033] 3. Connect the high-frequency spread spectrum module: In the existing technology, it is a fully functional, independent "spread spectrum head" or "harmonic mixer".

[0034] In this embodiment, it is a subordinate subsystem for high-frequency band (e.g., 67GHz ~ 110GHz) excitation generation and response reception. Its operating frequency band start point is strictly aligned with the host's maximum native output frequency, and the output / input is subject to switching management by a switch.

[0035] Interface standardization and functional subordination: its role has shifted from "independent measurement unit" to "dedicated generator and receiver that provides high-frequency material for synthesizing full-band signals." This positioning is key to achieving "seamless integration" with native frequency bands rather than "simple replacement."

[0036] The synergistic effect of the above core protection points 1-3: The architecture works together to form a "reconfigurable signal path": this combination defines a hardware-seamless and logically controllable dual-channel processing system. The signal flow is highly programmable: during transmission, low-frequency or high-frequency excitation paths can be dynamically selected, and during reception, the response signal can be routed to the corresponding analysis channel. The ultra-wideband switch, as the core selector, ensures that low-frequency and high-frequency signals can be independently excited and acquired in preset, physically isolated paths, and achieves quasi-simultaneous measurement through rapid switching, eliminating the uncertainty caused by frequency band splicing at the physical level.

[0037] Functional collaboration addresses the challenge of calibration traceability: when the switch routes the signal to the low-frequency path (via the first dual directional coupler), this path provides a traceable accuracy benchmark for the entire system. Measurements from the high-frequency path can be compared and verified at crossover points (e.g., 67 GHz) with measurements taken when switched to the low-frequency path. The switch ensures strict control over the signal path in both time and space, making it possible to transfer calibration confidence from the low-frequency band to the high-frequency band via cross-validation, thereby improving the consistency and reliability of measurements across the entire ultra-wideband.

[0038] Synergistic effects give rise to a new paradigm of "intelligent direct scanning": it is this programmable signal flow defined by a switch that ultimately presents to the user as an intelligent instrument whose behavior is highly consistent with the standard vector network detector (set start and end frequencies, click to scan), but with a greatly expanded frequency range. This "seamless uniformity of experience" and "automatic frequency band switching" is a completely new measurement paradigm that cannot be achieved by discrete solutions that rely on manually changing connections.

[0039] The switching logic of the ultra-wideband switch 3 is deeply integrated with the maximum native output frequency of the vector network analyzer host: one channel directly carries the continuous low-frequency signal generated by the host, from the lowest frequency to its maximum native frequency; the other channel carries the high-frequency signal after frequency conversion and expansion by the high-frequency spread spectrum module 2. The core objective of this design is to absolutely ensure that the host's core performance, such as source matching, power flatness, and signal purity within its native frequency band, is not compromised by the introduction of the expansion module. It allows the low-frequency signal to completely bypass the high-frequency module, which may introduce additional noise, nonlinearity, and errors, fundamentally guaranteeing the purity and highest accuracy of the reference measurement path. This is an optimized architectural decision made under the inherent contradiction between "pursuing the ultimate bandwidth expansion" and "defending the core measurement fidelity".

[0040] High-frequency spread spectrum module 2 includes: A transmit link is used to multiply the input second low-frequency radio frequency signal RF2 to generate a high-frequency excitation signal; the transmit link includes at least a first frequency multiplier 4 and an isolator 5 connected in sequence. A built-in second dual directional coupler 6 is coupled to the output of the transmit link to extract the high-frequency incident signal input to the device under test and the high-frequency reflected signal from the device under test; At least one mixer receiving link is used to receive the signal extracted by the built-in second dual directional coupler 6 and mix it with a high-frequency local oscillator signal LO. After down-conversion, the reference intermediate frequency signal Ref.IF and the measurement intermediate frequency signal Mea.IF are output.

[0041] The high-frequency spread spectrum module also includes a single-channel power divider 7 and two-channel mixer receiver links; Local oscillator power divider 7 is used to split one high-frequency local oscillator signal LO into two paths; One of the mixing receiver links serves as a reference channel, which includes a second frequency multiplier 8 and a first frequency mixer 9 connected in sequence. The first frequency mixer 9 is used to mix the frequency-multiplied local oscillator signal with the incident signal extracted by the second dual directional coupler 6, and output a reference intermediate frequency signal Ref.IF. Another mixing receiver link serves as a measurement channel, which includes a third frequency multiplier 10, a second frequency mixer 11, and an intermediate frequency power amplifier 12 connected in sequence. The second frequency mixer 11 is used to mix the frequency-multiplied local oscillator signal with the reflected or transmitted signal extracted by the second dual directional coupler 6, and output the measurement intermediate frequency signal Mea.IF.

[0042] Local oscillators (local oscillators with power dividers): This is the only reliable means to ensure strict phase synchronization between the reference and measurement channels during the mixing process, thereby ensuring the accuracy of vector phase measurement. Using two independent local oscillators would make the phase relationship undeterminable.

[0043] Asymmetric amplification (adjustable only for the measurement path): This innovatively enables independent optimization of the dynamic range of the device under test's response signal without altering the scale of the reference signal. This is specifically designed for the unique requirements of network analyzers that must simultaneously and accurately measure both the incident (reference) and reflected (measurement) waves, and is not a general-purpose receiver design.

[0044] In the mixing and receiving link of the measurement channel, the power amplifier 12 connected in series after the second mixer 11 is an adjustable gain power amplifier.

[0045] A first dual-directional coupler 1 is connected to the first channel port of the ultra-wideband switch 3, and its coupling port outputs a reference signal Ref. for characterizing the energy of the incident wave and a measurement signal Mea. for characterizing the energy of the reflected wave or the transmitted wave.

[0046] Clearly defined signal interfaces and data flows: By explicitly defining the reference signal Ref. and the measurement signal Mea., a standardized data interface protocol is essentially defined between the low-frequency path and the host. This ensures that the functions of each component in the system are clearly defined, providing an indispensable logical basis for the host to synchronously process two data streams and correctly synthesize S-parameters. It is a necessary information definition for the system to function as a whole.

[0047] The ultra-wideband switch 3, the first dual directional coupler 1, and the high-frequency spread spectrum module 2 are integrated and packaged in a unified shielded housing.

[0048] The ultimate manifestation and commercial necessity of functional integration: This feature transforms the aforementioned precision RF architecture into a user-plug-and-play, reliably calibrated "instrument." It eliminates the greatest source of uncertainty by replacing all external movable connections with internal permanent microwave interconnects; and ensures long-term stability through unified shielding and thermal design. This allows the extender itself to be treated as a standalone "calibration unit," a decisive step towards achieving highly reliable commercial testing, its technological sophistication reflected in its overall electromagnetic and mechanical design.

[0049] The second embodiment of the present invention: This embodiment of a vector network analyzer frequency extension system includes: A vector network analyzer host is used to generate a first low-frequency band radio frequency signal RF1 and a second low-frequency band radio frequency signal RF2; A frequency extender as described above has its first input port connected to the host of a vector network analyzer to receive a first low-frequency band radio frequency signal RF1, and its second input port connected to the host of the vector network analyzer to receive a second low-frequency band radio frequency signal RF2. The test port of the frequency extender is used to output a continuous spectrum excitation signal covering the frequency range from the lower limit of the first low-frequency band RF1 signal to the upper limit of the extended high-frequency band to the device under test, and to receive the full-band response signal from the device under test. The vector network analyzer host calculates the S-parameters of the device under test in the ultra-wideband based on the low-frequency band and the down-converted high-frequency band signal in the response signal.

[0050] The third embodiment of the present invention: The continuous frequency sweep measurement method of the frequency extender described above in this embodiment includes the following steps in sequence: Step 1: The vector network analyzer host generates a continuous sweep frequency signal covering its native frequency band as the first low-frequency band RF signal RF1, and at the same time generates a single frequency point or narrowband sweep frequency signal as the second low-frequency band RF signal RF2. Step 2: Control the ultra-wideband switch 3 to select the first low-frequency band RF signal RF1 to the transmission path. After being processed by the first dual directional coupler 1 in the expander, the first low-frequency band RF signal RF1 is directly fed to the selected channel of the ultra-wideband switch 3, ready to be output to the device under test; Step 3: Control the ultra-wideband switch 3 to switch to another channel, selecting the second low-frequency band RF signal RF2 to the transmission path. The second low-frequency band RF signal RF2 is then up-converted by the high-frequency spread spectrum module 2 in the expander and fed to the corresponding channel of the ultra-wideband switch 3; Step 4: Through the fast channel switching and signal synthesis control of the ultra-wideband switch 3, a continuous spectrum excitation signal covering from the low-frequency start point to the high-frequency cutoff point is generated and output on the test port in a time-division manner, and applied to the device under test; Step 5: The response signal from the device under test enters the ultra-wideband switch 3 through the test port and is routed to different receiving paths according to its frequency range: the low-frequency response signal is routed to the first dual directional coupler 1, and the high-frequency response signal is routed to the high-frequency spread spectrum module 2. Step 6: The low-frequency response signal is sampled by the first dual directional coupler 1 to obtain the reference signal Ref. and the measurement signal Mea. and is directly returned to the vector network analyzer host; the high-frequency response signal is down-converted into the reference intermediate frequency signal Ref.IF and the measurement intermediate frequency signal Mea.IF in the high-frequency spread spectrum module 2 and then returned to the vector network analyzer host. Step 7: The vector network analyzer host synchronously processes the received signals of the corresponding path according to the switch status, calculates and synthesizes the S-parameter curve of the device under test in the entire ultra-wideband by timing alignment and data splicing.

[0051] Fourth embodiment of the present invention: like Figures 1-2 As shown, the core purpose of designing the vector network analyzer frequency extender in this embodiment is to overcome the frequency limitations of the instrument itself in an economical and efficient manner, enabling it to measure higher frequency microwave, millimeter-wave, and even terahertz devices. It uses an external module for frequency conversion, allowing the host computer to process high-frequency signals that could not be directly generated or received, thereby protecting the user's existing equipment investment while meeting the high-frequency testing needs of cutting-edge technology fields.

[0052] This embodiment designs a frequency extender for a millimeter-wave vector network analyzer. This extender is used with a 67GHz vector network analyzer host and can achieve continuous measurement of S-parameters in the 10MHz~110GHz frequency band.

[0053] To achieve the above objectives, this embodiment adopts the following technical solution: To achieve continuous S-parameter measurement in the 10MHz to 110GHz frequency band, the entire band is divided into two sub-bands: 10MHz~67GHz and 67GHz~110GHz. The system uses a vector network analyzer host with 10MHz~67GHz signal output capability, and is externally connected to a 10MHz~110GHz vector network analyzer frequency extender. This frequency extender integrates a 67GHz~110GHz spread spectrum module (i.e., high-frequency spread spectrum module 2), a 10MHz~67GHz dual directional coupler (i.e., first dual directional coupler 1), and a 10MHz~110GHz switch (i.e., ultra-wideband switch 3).

[0054] The specific signal path is as follows: The 10MHz~67GHz RF signal generated by the vector network analyzer host, i.e., the first low-frequency band RF signal RF1, is fed to the low-frequency input channel of the ultra-wideband switch 3 after passing through the first dual directional coupler 1. Simultaneously, another low-frequency signal output by the vector network analyzer host, i.e., the second low-frequency band RF signal RF2, is first sent to the high-frequency spread spectrum module 2, up-converted to the 67GHz~110GHz band after frequency multiplication, and then fed to the high-frequency input channel of the ultra-wideband switch 3. The ultra-wideband switch 3 rapidly switches its channels, sequentially outputting either low-frequency or high-frequency signals from the common port, thereby synthesizing an excitation signal covering 10MHz~110GHz in the time domain and applying it to the system test port to achieve integrated measurement of S-parameters across the entire frequency band.

[0055] The high-frequency spread spectrum module 2 operates based on the principle of frequency multiplication and mixing reception. During operation, the RF transmitting link first multiplies the input second low-frequency RF signal RF2 via the first frequency multiplier 4, and then performs impedance isolation and signal protection through the isolator 5, thereby generating the required high-frequency excitation signal. This signal is applied to the device under test (DUT) via the second dual-directional coupler 6. Simultaneously, the second dual-directional coupler 6 is also responsible for separating and extracting the forward incident signal and the reverse reflected signal. At the receiving end, the local oscillator power divider splits one high-frequency local oscillator signal LO into two paths, which are fed into the reference and measurement mixing receiving links respectively. The local oscillator signals in both links are first multiplied by a local oscillator frequency multiplier (second frequency multiplier 8 or third frequency multiplier 10), and then mixed with the signal extracted by the second dual-directional coupler 6. In the measurement receiving link, a power amplifier 12 is introduced after mixing to increase the amplitude of the measurement signal, ultimately obtaining the reference intermediate frequency signal Ref.IF and the measurement intermediate frequency signal Mea.IF, completing the down-conversion detection of the incident and reflected signals of the DUT.

[0056] The first dual directional coupler 1 is placed in the signal path, and its direct end outputs a first low-frequency radio frequency signal RF1, while the two coupling ports couple out a reference signal Ref. and a measurement signal Mea., respectively. The reference signal is used to characterize the energy of the incident wave, and the measurement signal is used to characterize the energy of the reflected wave or the transmitted wave, thereby providing the network analyzer host with the vector data required for S-parameter calculation.

[0057] The ultra-wideband switch 3 is a multi-port microwave device used for high-speed path selection and routing of radio frequency signals over an extremely wide frequency range. The switch has one common port and two independent input channel ports. During operation, the common port is used to input or output radio frequency signals covering 10MHz to 110GHz. In receiving mode, the switch routes the composite radio frequency signal input to the common port to the corresponding channel port according to a preset control timing sequence: the lower frequency band signal (10MHz to 67GHz) is routed to the first channel port, while the higher frequency band signal (67GHz to 110GHz) is routed to the second channel port, thus achieving high-isolation decoupling of the two frequency bands. Conversely, in transmitting mode, when the low-frequency band signal and the high-frequency band signal are input from the first channel port and the second channel port respectively, the switch, according to control commands, rapidly switches and sequentially selects the two signals for output to the common port, thereby synthesizing a single excitation signal covering 10MHz to 110GHz in the time domain, realizing the timing merging and output function of the signals.

[0058] The specific implementation process of this embodiment is as follows: Figure 1 and Figure 2 As shown: like Figure 1 The frequency extender, through its internally integrated ultra-wideband switch, distributes the full-band signal to two physical paths—low frequency (10MHz~67GHz) and high frequency (67GHz~110GHz)—in a time-division multiplexing manner. For the low-frequency path, the first low-frequency RF signal RF1 (10MHz~67GHz) generated by the vector network analyzer host is coupled and sampled by the internal first dual directional coupler 1, and then selected to the low-frequency channel by the ultra-wideband switch. For the high-frequency path, another signal output by the vector network analyzer host, the second low-frequency RF signal RF2, first enters the high-frequency spread spectrum module 2, where it is up-converted to the 67GHz~110GHz band through a frequency multiplication mechanism, and then selected to the high-frequency channel by the ultra-wideband switch. The ultra-wideband switch, through a fast switching mechanism, sequentially outputs the two signals at its common terminal, thereby synthesizing them in the time domain into a continuous spectrum excitation signal covering 10MHz to 110GHz. This design enables timing synthesis and seamless excitation of the native and extended frequency bands of the vector network host on a single port, thereby completing the S-parameter measurement of the entire ultra-wideband.

[0059] like Figure 2 The high-frequency spread spectrum module 2 mainly includes: an RF transmission link, a second dual-directional coupler 6, a mixer receiving link, and a local oscillator power divider. The RF transmission link includes, for example, a first frequency multiplier 4 that receives the RF signal (second low-frequency band RF signal RF2) and an isolator 5 connected between the first frequency multiplier 4 and the second dual-directional coupler 6. This RF transmission link provides the excitation signal required by the measured signal. The second dual-directional coupler 6 acts as a signal separation device, extracting the input and reflected signals of the measured signal. The mixer receiving link is divided into a reference receiving link and a measurement receiving link, measuring the input and reflected signals of the measured signal. The reference receiving link includes, for example, a second frequency multiplier 8 and a first mixer 9. The measurement receiving link includes, for example, a third frequency multiplier 10, a second mixer 11, and an intermediate frequency power amplifier 12. The local oscillator power divider splits one input signal into two paths, providing excitation signals to the two mixer receiving links respectively.

[0060] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0061] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0062] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A frequency extender for a vector network analyzer, characterized in that, include: An ultra-wideband switch (3) has a control port, a common port, a first channel port and a second channel port, wherein the control port is controlled by a test controller and the common port serves as the test port of the frequency extender; A first dual directional coupler (1) has an input terminal for receiving a first low-frequency band radio frequency signal (RF1) from the vector network analyzer host, and its through terminal is connected to the first channel port of the switch; A high-frequency spread spectrum module (2) has an input terminal for receiving a second low-frequency radio frequency signal (RF2) from the vector network analyzer host, and its output terminal is connected to the second channel port of the ultra-wideband switch (3); The ultra-wideband switch (3) is configured such that: the control port is used for signal selection; in the transmission path, the low-frequency signal of the first channel port and the high-frequency signal of the second channel port are sequentially switched to the common port output; in the receiving path, the signal received by its common port is sequentially directed to the first channel port and the second channel port.

2. The vector network analyzer frequency extender as described in claim 1, characterized in that, The frequency switching point of the ultra-wideband switch (3) is consistent with the maximum native output frequency of the vector network analyzer host; the low frequency band covers the continuous frequency band from the lowest frequency of the vector network analyzer host to the frequency switching point, and the high frequency band covers the continuous frequency band from the frequency switching point to the maximum spread frequency of the high frequency spread spectrum module (2).

3. A vector network analyzer frequency extender as described in claim 2, characterized in that, The high-frequency spread spectrum module (2) includes: A transmit link is used to multiply the input second low-frequency band radio frequency signal (RF2) to generate a high-frequency band excitation signal; the transmit link includes at least a first frequency multiplier (4) and an isolator (5) connected in sequence. A built-in second dual directional coupler (6) is coupled to the output of the transmit link to extract the high-frequency incident signal input to the device under test and the high-frequency reflected signal from the device under test; At least one mixer receiving link is used to receive the signal extracted by the built-in second dual directional coupler (6) and mix it with a high-frequency local oscillator signal (LO). After down-conversion, the reference intermediate frequency signal (Ref.IF) and the measurement intermediate frequency signal (Mea.IF) are output.

4. A vector network analyzer frequency extender as described in claim 3, characterized in that, The high-frequency spread spectrum module also includes a single-vibration power divider (7) and two-channel mixer receiving links; The local oscillator power divider (7) is used to split one high-frequency local oscillator signal (LO) into two; One of the mixing receiver links serves as a reference channel, which includes a second frequency multiplier (8) and a first frequency mixer (9) connected in sequence. The first frequency mixer (9) is used to mix the frequency-multiplied local oscillator signal with the incident signal extracted by the second dual directional coupler (6) and output a reference intermediate frequency signal (Ref.IF). Another mixing receiver link serves as a measurement channel, which includes a third frequency multiplier (10), a second frequency mixer (11), and an intermediate frequency power amplifier (12) connected in sequence. The second frequency mixer (11) is used to mix the frequency-multiplied local oscillator signal with the reflected or transmitted signal extracted by the second dual directional coupler (6) to output the measurement intermediate frequency signal (Mea.IF).

5. A vector network analyzer frequency extender as described in claim 4, characterized in that, In the mixing and receiving link of the measurement channel, the power amplifier (12) connected in series after the second mixer (11) is an adjustable gain power amplifier.

6. A vector network analyzer frequency extender as described in claim 1, characterized in that, The first dual directional coupler (1) connected to the first channel port of the ultra-wideband switch (3) outputs a reference signal (Ref.) for characterizing the energy of the incident wave and a measurement signal (Mea.) for characterizing the energy of the reflected wave or the transmitted wave, respectively.

7. A vector network analyzer frequency extender as described in claim 1, characterized in that, The ultra-wideband switch (3), the first dual directional coupler (1), and the high-frequency spread spectrum module (2) are integrated and packaged in a unified shielded housing.

8. A frequency extension system for a vector network analyzer, characterized in that, include: A vector network analyzer host is used to generate a first low-frequency band radio frequency signal (RF1) and a second low-frequency band radio frequency signal (RF2). A frequency extender as described in any one of claims 1 to 7, wherein a first input port is connected to the vector network analyzer host to receive the first low-frequency band radio frequency signal (RF1), and a second input port is connected to the vector network analyzer host to receive the second low-frequency band radio frequency signal (RF2). The test port of the frequency extender is used to output a continuous spectrum excitation signal covering the frequency range from the lower limit of the first low-frequency band radio frequency signal (RF1) to the upper limit of the extended high-frequency band to the device under test, and to receive the full-band response signal from the device under test; the vector network analyzer host calculates the S-parameters of the device under test in the ultra-wideband based on the low-frequency band and the down-converted high-frequency band signal in the response signal.

9. A continuous frequency sweep measurement method for a frequency extender as described in any one of claims 1 to 7, characterized in that, The steps are as follows: Step 1: The vector network analyzer host generates a continuous sweep frequency signal covering its native frequency band as the first low-frequency band radio frequency signal (RF1), and at the same time generates a single frequency point or narrowband sweep frequency signal as the second low-frequency band radio frequency signal (RF2). Step 2: The first low-frequency radio frequency signal (RF1) is processed by the first dual directional coupler (1) and the first channel of the ultra-wideband switch (3) in the expander, and the second low-frequency radio frequency signal (RF2) is processed by the high-frequency spread spectrum module (2) and the second channel of the ultra-wideband switch (3) in the expander. Step 3: The ultra-wideband switch (3) can generate a continuous spectrum excitation signal covering the low-frequency start point to the high-frequency cutoff point by switching its two channels, and apply it to the device under test through the test port; Step 4: The response signal from the device under test enters the ultra-wideband switch (3) through the test port, and is switched by the switch control terminal to be introduced into the first channel port and the second channel port in sequence; Step 5: The low-frequency response signal is sampled by the first dual directional coupler (1) to obtain the reference signal (Ref.) and the measurement signal (Mea.) and is directly returned to the vector network analyzer host; the high-frequency response signal is down-converted into the reference intermediate frequency signal (Ref.IF) and the measurement intermediate frequency signal (Mea.IF) in the high-frequency spread spectrum module (2) and then returned to the vector network analyzer host; Step 6: The vector network analyzer host processes the two received signals sequentially, calculates and synthesizes the S-parameter curves of the device under test throughout the entire ultra-wideband.

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