CN106199188A - A kind of device and method utilizing the change of removal cable phase place in circulator calibration vector field measurement - Google Patents

Abstract

A device for using a circulator to calibrate the phase change of a mobile cable in vector field measurement, including a radio frequency synthesizer and a local oscillator frequency synthesizer; the radio frequency synthesizer is connected to a first directional coupler, and the straight-through end of the first directional coupler is connected to a mobile cable , the coupling end is connected to the reference mixer; the mobile cable is connected to port one of the circulator, and the port two of the circulator is connected to the second directional coupler through the amplifier, and the straight-through end of the second directional coupler is connected to the radio frequency doubler, The coupling end is connected to three ports of the circulator, and the RF frequency multiplier is connected to the receiver; the intermediate frequency output terminal of the reference mixer is connected to the acquisition card; the local oscillator frequency synthesizer is connected to the local oscillator frequency multiplier and the reference The mixer and the local oscillator frequency multiplier are connected to the receiver; the receiver is connected to the acquisition card through the intermediate frequency processing module. The invention improves the signal-to-noise ratio of the reflected signal, and solves the problem that the reflected signal is too small to detect when the moving cable is too long.

Description

An Apparatus for Calibrating the Phase Variation of Moving Cables in Vector Field Measurement Using a Circulator and method

technical field

The invention belongs to the technical field of terahertz measurement, and in particular relates to a device and method for using a circulator to calibrate the phase change of a moving cable in terahertz frequency bands (including millimeter wave and submillimeter wave bands) during vector field measurement.

Background technique

Vector field measurement refers to the simultaneous measurement of the magnitude and phase distribution of an electromagnetic field. This measurement technology can deduce the three-dimensional electromagnetic field distribution and propagation characteristics of the radiation source to be measured in the whole space range by scanning the two-dimensional vector field shape measurement of a plane, cylinder or sphere, so it is widely used in large reflector antennas, feeder Performance measurements of source speakers, millimeter wave imaging systems, and quasi-optical systems.

A typical terahertz plane vector field measurement system is shown in Figure 1, in which the terahertz emission source is installed on a high-precision XY electric translation stage, and the terahertz signal is generated by multiplying the frequency of the microwave signal. During the measurement process, the electric translation stage scans on the selected plane, and then obtains the vector field information to be measured. The moving cable connected to the terahertz signal source will move along with the translation stage. Since the phase of the moving cable will change with the shape of the cable, the movement of the cable will introduce a certain phase error in the microwave frequency band. In the microwave frequency band, this error is negligible, but in the terahertz band, this phase error is amplified with the frequency multiplication of the signal. A tiny jitter in the phase of a 10GHz signal will be magnified 100 times at 1THz. The phase error introduced by the moving cable varies with the number of signal multiplications. In addition, the phase change is also related to the scanned area: the larger the scanned area, the larger the phase error introduced. Therefore, the phase error introduced by the movement of the moving cable will seriously affect the phase accuracy of the vector field.

In order to effectively reduce the effects of the above problems, the phase error caused by the movement of the moving cable must be calibrated. A simple way is to add an artificial impedance mismatch to the terahertz emission source, so that the incident microwave signal has a certain reflection, so that the reflected signal is reflected back along the same cable, and measured by detecting the phase of the reflected signal The movement of the moving cable introduces a phase error. However, when the length of the cable is relatively long, due to the loss of the cable itself, the strength of the reflected signal is too small to accurately obtain its phase, and a larger phase error will be introduced instead. If this signal can be amplified before being reflected back to the moving cable, and then the signal is injected into the moving cable, the signal-to-noise ratio of the reflected signal can be effectively improved, and then the phase error introduced by the moving cable can be calibrated.

Contents of the invention

Aiming at the deficiencies in the prior art, the present invention provides a device and method for calibrating the phase change of a moving cable in vector field measurement by using a circulator.

To achieve the above object, the present invention adopts the following technical solutions:

A device for using a circulator to calibrate the phase change of a moving cable in vector field measurement, characterized in that it includes a radio frequency synthesizer and a local oscillator frequency synthesizer; the radio frequency synthesizer is connected to the first directional coupler, and the first directional coupler straight-through end It is connected to the mobile cable, and the coupling end is connected to the reference mixer; the mobile cable is connected to port one of the circulator, and the port two of the circulator is connected to the second directional coupler through the amplifier, and the straight-through end of the second directional coupler is connected to the RF multiplier The frequency converter is connected, the coupling end is connected to the port three of the circulator, the RF frequency multiplier is connected to the receiver; the intermediate frequency output terminal of the reference mixer is connected to the acquisition card; Frequency converter and reference mixer, the local oscillator frequency multiplier is connected to the receiver; the receiver is connected to the acquisition card through the intermediate frequency processing module.

In order to optimize the above technical solutions, the specific measures taken also include:

The first directional coupler is a dual directional coupler, the reference mixer includes a reference mixer one and a reference mixer two, and the two coupling ends of the first directional coupler are respectively connected to the reference mixer One is connected to reference mixer two.

The intermediate frequency output end of the reference mixer 1 is connected to the acquisition card, and the intermediate frequency output end of the reference mixer 2 is connected to the acquisition card through a duplexer.

The power divider includes a first power divider and a second power divider, and the local oscillator frequency is divided into two paths through the first power divider, one path is connected to the local oscillator frequency multiplier, and the other path is passed through the second power divider It is further divided into two paths, which are respectively connected to the reference mixer 1 and the reference mixer 2.

The acquisition card is a high-speed A/D acquisition card.

The receiver includes a HEB mixer.

The coupling coefficient of the second directional coupler is equivalent to the amplification factor of the amplifier.

In addition, a calibration method using the above-mentioned device for calibrating phase changes of moving cables in vector field measurements using a circulator is proposed:

The radio frequency synthesizer generates the radio frequency microwave signal, and the local oscillator frequency synthesizer generates the local oscillator microwave signal. After the radio frequency microwave signal and the local oscillator microwave signal are multiplied M times, the intermediate frequency signal is generated by the receiver, where M is the frequency multiplier of the terahertz signal. frequency;

The radio frequency microwave signal flows in from port one of the circulator through the mobile cable, passes through the amplifier and the second directional coupler, flows from the coupling end of the second directional coupler through port three of the circulator, and then injects into the mobile cable, and is mixed by the reference Receiver two;

Reference mixer 1 outputs a system reference signal, and reference mixer 2 outputs a mobile reflection signal;

Use the duplexer to collect the intermediate frequency signal and the mobile reflection signal together by the acquisition card, and the acquisition card also collects the system reference signal;

The phase information is obtained according to the signal collected by the acquisition card, and the phase error introduced by the moving cable is calculated and calibrated.

And, further:

The initial phases of RF frequency synthesis and local oscillator frequency synthesis signals are respectively and The phase of the system reference signal is:

${\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; r</span>}\mathrm{<span\; class="notranslate">\; e</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; L</span>}\mathrm{<span\; class="notranslate">\; o</span>}}^{\mathrm{<span\; class="notranslate">\; 0</span>}}$

The electrical length of the moving cable is The phase of the RF signal entering reference mixer two is:

${\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 2</span>}{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; l</span>}}$

The phase of the reference mixer two IF output is:

${\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; r</span>}\mathrm{<span\; class="notranslate">\; e</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; L</span>}\mathrm{<span\; class="notranslate">\; o</span>}}^{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 2</span>}{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; l</span>}}$

The phase of the detected change over the moving cable is thus:

${\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; l</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; r</span>}\mathrm{<span\; class="notranslate">\; e</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; r</span>}\mathrm{<span\; class="notranslate">\; e</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; 2</span>}$

The detected intermediate frequency phase is f _IF , then the calibrated intermediate frequency phase is:

${\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; I</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; c</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; l</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; I</span>}\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; mf</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; l</span>}}<span\; class="notranslate">\; .</span>$

The beneficial effects of the invention are: a circulator is connected to the end of the moving cable, and the three-port characteristic of the circulator is used to amplify the reflection signal first and then reflect the signal. The device and method are simple to implement, can effectively improve the signal-to-noise ratio of reflected signals, solve the problem of too small reflected signals caused by too long cables, and can be applied to large-scale vector field measurement systems.

Description of drawings

Figure 1 is a system block diagram of a general vector field.

Fig. 2 is a block diagram of the vector field measurement system and the mobile cable phase calibration of the present invention.

Figure 3 is a block diagram of a specific embodiment of the invention.

Reference signs are as follows: RF frequency synthesizer 1, local oscillator frequency synthesizer 2, first directional coupler 3, mobile cable 4, reference mixer one 5, reference mixer two 6, circulator 7, amplifier 8, the first Two directional coupler 9, radio frequency multiplier 10, receiver 11, acquisition card 12, local oscillator frequency multiplier 13, intermediate frequency processing module 14, duplexer 15, first power divider 16, second power divider 17 , reference mixer 18 .

detailed description

The present invention is described in further detail now in conjunction with accompanying drawing.

As shown in Figure 2, the device for using the circulator to calibrate the phase change of the mobile cable in the vector field measurement includes a radio frequency synthesizer 1 and a local oscillator frequency synthesizer 2, the radio frequency synthesizer 1 is connected with the first directional coupler 3, and the first directional coupler The device 3 is a double directional coupler, the straight-through end is connected to the mobile cable 4, and the two coupling ends are connected to the reference mixer one 5 and the reference mixer two 6 respectively.

The mobile cable 4 is connected to port one of the circulator 7, and the port two of the circulator 7 is connected to the amplifier 8, and the output terminal of the amplifier 8 is connected to the second directional coupler 9, and its coupling coefficient is equivalent to the amplification factor of the amplifier 8. The through end of the second directional coupler 9 is connected to the radio frequency doubler 10 , and the coupling end is connected to the port three of the circulator 7 . The radio frequency multiplier 10 is connected to the radiation source to be measured and the receiver 11 capable of receiving and mixing radio frequency signals in turn, and the receiver 11 is connected to the acquisition card 12 through the intermediate frequency processing module 14 and the duplexer 15 in turn, and the acquisition card 12 can adopt High-speed A/D acquisition card.

The IF output end of reference mixer one 5 is connected to the acquisition card 12 , and the IF output end of reference mixer two 6 is connected to the acquisition card 12 through a duplexer 15 . The local oscillator frequency synthesis 2 is divided into two paths by the first power divider 16, one path is connected to the local oscillator frequency multiplier 13, and the other path is divided into two paths by the second power divider 17, respectively connected to the reference mixer-5 It is connected to the reference mixer 26.

When the above devices are used for measurement, the radio frequency synthesizer 1 generates a radio frequency microwave signal, and the local oscillator frequency synthesizer 2 generates a local oscillator microwave signal. signal, where M is the multiplication frequency of the terahertz signal.

The radio frequency microwave signal flows in from the port one of the circulator 7 through the mobile cable 4, passes through the amplifier 8 and the second directional coupler 9, flows through the port three of the circulator 7 from the coupled end of the second directional coupler 9, and then injects into the mobile Cable 4, received by reference mixer two 6. The first reference mixer 5 outputs the system reference signal, and the second reference mixer 6 outputs the mobile reflection signal; the intermediate frequency signal and the mobile reflection signal are collected together by the acquisition card 12 by the duplexer 15, and the acquisition card 12 also collects the system reference signal.

The signals collected by the collection card 12 are time-domain signals, and after FFT transformation, the phase information of each signal is obtained. The phase analysis of the system is as follows: components such as circulators, directional couplers, and power dividers are fixed. When the radio frequency signal passes through these components, only a fixed phase will be added, which has no effect on the final detected phase of the system. consider.

Assume that the initial phase of the RF frequency synthesis and local oscillator frequency synthesis signals is and The phase of the system reference signal is:

${\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; r</span>}\mathrm{<span\; class="notranslate">\; e</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; L</span>}\mathrm{<span\; class="notranslate">\; o</span>}}^{\mathrm{<span\; class="notranslate">\; 0</span>}}$

Assume that the electrical length of the moving cable 4 (which can be equated to the phase of the moving cable 4 here) is The phase of the RF signal entering the reference mixer 26 is:

${\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 2</span>}{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; l</span>}}$

The coefficient 2 is because the signal passes through the mobile cable 4 twice, and the phase output by the reference mixer 2 6 IF is:

${\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; r</span>}\mathrm{<span\; class="notranslate">\; e</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; L</span>}\mathrm{<span\; class="notranslate">\; o</span>}}^{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 2</span>}{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; l</span>}}$

The phase of the detected change via the moving cable 4 is thus:

${\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; l</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; r</span>}\mathrm{<span\; class="notranslate">\; e</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; r</span>}\mathrm{<span\; class="notranslate">\; e</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; 2</span>}$

Assuming that the detected IF phase is f _IF , the calibrated IF phase is:

${\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; I</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; c</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; l</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; I</span>}\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; mf</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; f</span>}}^{\mathrm{<span\; class="notranslate">\; l</span>}}<span\; class="notranslate">\; .</span>$

Phase errors introduced by the moving cable 4 are thus detected and calibrated in the final test results.

As shown in Figure 3, the device is applied to the 495GHz vector field measurement system, in which the frequencies of the RF frequency synthesizer and the local oscillator frequency synthesizer are microwave signals of 13.75GHz and 13.76GHz, respectively, after 36 frequency multiplication, the 495GHz The Hertz RF signal and the 495.36GHz terahertz local oscillator signal are mixed by the HEB mixer to generate a 360MHz intermediate frequency signal. The system 10MHz reference signal is generated by reference mixer one 5, and the radio frequency microwave signal is received by reference mixer two 6 after being reflected by moving cable 4. The output signal of the reference mixer 2 6 is collected by the channel 1 of the acquisition card 12 through the duplexer 15 together with the 360MHz intermediate frequency signal. The acquisition card 12 specifically adopts the NI5772R dual-channel high-speed A/D acquisition card. The signal collected by the acquisition card 12 is a time-domain signal. After FFT transformation, the phases of the 360MHz intermediate frequency signal, the system 10MHz reference signal and the mobile reflection signal can be obtained respectively. After data processing, the phase change of the mobile cable can be obtained and calibrated.

The above are only preferred implementations of the present invention, and the protection scope of the present invention is not limited to the above-mentioned embodiments, and all technical solutions under the idea of the present invention belong to the protection scope of the present invention. It should be pointed out that for those skilled in the art, some improvements and modifications without departing from the principle of the present invention should be regarded as the protection scope of the present invention.

Claims (9)

1. one kind utilizes the device of removal cable phase place change in circulator calibration vector field measurement, it is characterised in that: include penetrating Again and again combine (1) and local oscillator frequency combines (2)；Radio frequency frequency is combined (1) and is connected with the first directional coupler (3), and the first directional coupler (3) is straight Go side is connected with removal cable (4), and coupled end is connected with parametric mixer；Removal cable (4) is connected to the port of circulator (7) One, the port two of circulator (7) is connected to the second directional coupler (9) by amplifier (8), the second directional coupler (9) Straight-through end is connected with radio frequency doubler (10), and coupled end is connected with the port three of circulator (7), and radio frequency doubler (10) is connected to Receiver (11)；The medium frequency output end of parametric mixer is connected to capture card (12)；Local oscillator frequency is combined (2) and is connected respectively by power splitter Being connected to local oscillator doubler (13) and parametric mixer, local oscillator doubler (13) is connected to receiver (11)；Receiver (11) passes through IF process module (14) is connected to capture card (12).

Utilizing the device of removal cable phase place change in circulator calibration vector field measurement the most as claimed in claim 1, it is special Levy and be: described first directional coupler (3) is dual directional coupler, and described parametric mixer includes parametric mixer one (5) With parametric mixer two (6), two coupled end of the first directional coupler (3) are mixed with parametric mixer one (5) and reference respectively Frequently device two (6) is connected.

Utilizing the device of removal cable phase place change in circulator calibration vector field measurement the most as claimed in claim 2, it is special Levy and be: the medium frequency output end of described parametric mixer one (5) is connected to capture card (12), described parametric mixer two (6) Medium frequency output end is connected with capture card (12) by duplexer (15).

Utilizing the device of removal cable phase place change in circulator calibration vector field measurement the most as claimed in claim 3, it is special Levy and be: described power splitter includes that the first power splitter (16) and the second power splitter (17), local oscillator frequency combine (2) by the first power splitter (16) being divided into two-way, a road is connected to local oscillator doubler (13), and the second power splitter (17) of separately leading up to is divided into again two-way, respectively It is connected with parametric mixer one (5) and parametric mixer two (6).

Utilizing the device of removal cable phase place change in circulator calibration vector field measurement the most as claimed in claim 4, it is special Levy and be: described capture card (12) is high-speed a/d capture card.

Utilizing the device of removal cable phase place change in circulator calibration vector field measurement the most as claimed in claim 4, it is special Levy and be: described receiver (11) includes HEB frequency mixer.

Utilizing the device of removal cable phase place change in circulator calibration vector field measurement the most as claimed in claim 4, it is special Levy and be: the coefficient of coup of described second directional coupler (9) is suitable with the amplification of amplifier (8).

8. one kind uses and utilizes removal cable phase in circulator calibration vector field measurement as according to any one of claim 4-7 The calibration steps of the device of position change, it is characterised in that including:

Radio frequency frequency combine (1) produce frequency microwave signal, local oscillator frequency combine (2) produce local oscillator microwave signal, frequency microwave signal and this After microwave signal of shaking is respectively through M frequency multiplication, being received machine (11) and produce intermediate-freuqncy signal, wherein M is the frequency multiplication of terahertz signal Number of times；

Frequency microwave signal flows into from the port one of circulator (7) through removal cable (4), fixed through amplifier (8) and second To bonder (9), the coupled end of the second directional coupler (9) flow through the port three of circulator (7), be re-introduced into removal cable (4), parametric mixer two (6) receive；

Parametric mixer one (5) exports system reference signal, parametric mixer two (6) output mobile reflected signal；Utilize duplex Intermediate-freuqncy signal is gathered together with mobile reflected signal by device (15) by capture card (12), and capture card (12) also acquisition system is with reference to letter Number；

Obtain phase information according to the signal that capture card (12) collects, calculate and calibrate the phase place that removal cable (4) is introduced Error.

Utilize the calibration of the device of removal cable phase place change in circulator calibration vector field measurement the most as claimed in claim 8 Method, it is characterised in that:

Radio frequency frequency combines (1) and local oscillator frequency combines the initial phase of (2) signal respectivelyAndThe phase place of system reference signal is:

$f_{ref}^0=f_{RF}^0-f_{LO}^0$

The electrical length of removal cable (4) isThe radiofrequency signal phase place entering parametric mixer two (6) is:

$f_{RF}^1=f_{RF}^0+2f_{RF}^l$

The phase place of parametric mixer two (6) intermediate frequency output is:

$f_{ref}^1=f_{RF}^0-f_{LO}^0+2f_{RF}^l$

Therefore the phase place through the change of removal cable (4) detected is:

$f_{RF}^l=(f_{ref}^1-f_{ref}^0)/2$

The intermediate frequency phase place detected is f_IF, then the intermediate frequency phase place after calibration is:

$f_{IF}^{cal}=f_{IF}-{\mathrm{Mf}}_{RF}^l.$