CN104111164A - Vector network analyzer based light wave component test calibration method - Google Patents

Abstract

The invention provides a vector network analyzer based light wave component test calibration method. A signal source of a vector network analyzer produces test signals, one test signal is coupled to the vector network analyzer through a coupler to be received by a receiver R1 channel, the other test signal enters an electro-optical conversion module, an optical signal output by the electro-optical conversion module is loaded to a light wave component to be tested, a transmission signal of the light wave component to be tested is converted into an electrical signal through a photovoltaic conversion module and received by a receiver B channel of the vector network analyzer, and a reflected signal of the light wave component to be tested is converted into an electrical signal through the other photovoltaic conversion module to be received by a receiver C channel of the vector network analyzer; the receiver R1 channel is a port 1, the receiver B channel is a port 2, and the receiver C channel is a port 3. The vector network analyzer based light wave component test calibration method is low in system cost, high in calibration accuracy, and simple in operation.

Description

A kind of calibration steps of the light wave component testing based on vector network analyzer

Technical field

The present invention relates to technical field of measurement and test, particularly a kind of calibration steps of the light wave component testing based on vector network analyzer.

Background technology

Along with the development of optical communication technique, the importance of light wave component testing and analysis all the more highlights.Current existing method of testing is divided into two kinds: a kind of is to use special light wave components and parts analyser, even with the tested components and parts of light wave direct-drive, analyze its reflection and transmission wave, directly measure tested part characteristic, the advantage of this method is instrument calibration technology maturation, but frequency (wavelength) resolution is lower; Another kind is to use photoelectronic method, uses microwave to be modulated to optical wavelength excitation measured piece, then transmission and reflected signal are demodulated to microwave frequency band analysis, and its advantage is that frequency (wavelength) resolution is higher, but systematic error is difficult to calibration.

Also have a kind of easy implementation method, directly use vector network analyzer and optoelectronic converter part to build light wave analysis platform, but the first step calibration of its calibration, its phase test result precision is not high.Light wave components and parts based on vector network analyzer calibration at present can only be led directly to calibration.

Summary of the invention

For the shortcoming of above-mentioned three kinds of light wave component testing methods, the present invention proposes a kind of optic component detection calibration method based on vector network analyzer.

Technical scheme of the present invention is achieved in that

A kind of calibration steps of the light wave component testing based on vector network analyzer, the signal source of vector network analyzer produces test signal, one drive test trial signal is coupled to vector network analyzer receiver R1 passage by coupling mechanism and receives, another drive test trial signal enters electrooptic conversion module, the light signal of electrooptic conversion module output loads on tested light wave components and parts, the signal transmission of tested light wave components and parts is converted to electric signal by photoelectric conversion module, by vector network analyzer receiver B passage, received, the reflected signal of tested light wave components and parts is received by vector network analyzer receiver C-channel after circulator is converted to electric signal by another photoelectric conversion module, described receiver R1 passage is port one, and receiver B passage is port 2, and receiver C-channel is port 3:

Port one microwave error comprises directional error EDF, transmission tracking error ESTF, source mismatch error ESF and skin tracking error E SRF;

E/O switching device model comprises the directional error EEODF of electric light converting transmission error coefficient ESOTF and E/O device microwave end;

O/E switching device model comprises the transmission error coefficient EOSTF of O/E device, the matching error EOESF of O/E device and an inner microwave matching error;

The microwave error of port 2 and port 3 comprises receiver transmission tracking error ERTF and receiver mismatches error E LF;

Tested light wave device model only comprises transmission error coefficient OS ₂₁with reflection error coefficient OS ₁₁two parameters;

Take tested light wave components and parts as test plane, the microwave error of the error of E/O and O/E device and port one, port 2, port 3 is merged, input end is used the inner receiver C/R1 of vector network analyzer, transmit port is vector network analyzer receiver B/R1, simplifies the light wave component testing error model based on vector network analyzer;

Calibration process comprises:

Step (a), will test E/O converter rear end vacant, test volume S in vector network analyzer _31Mand S _21Mfor:

$S_{31M}=\frac{C}{R_1}=e_{00}=M_1---\left(1\right)$

$S_{21M}=\frac{B}{R_1}=e_{31}=M_2---\left(2\right)$

Step (b), access light total reflection meter, its reflection characteristic coefficient OS ₁₁=1, test volume S in vector network analyzer _31Mfor:

$S_{31M}=\frac{C}{R_1}=e_{00}+\frac{e_{10}*e_{01}}{1-e_{41}*e_{14}}=M_3---\left(3\right)$

Step (c), is directly connected E/O converter back end test port with O/E converter head end test port, transport property coefficient OS ₂₁=1, test volume S in vector network analyzer _21Mfor:

$S_{21M}=\frac{B}{R_1}=e_{31}+\frac{e_{10}*e_{32}}{1-e_{35}*e_{53}}=M_4---\left(4\right)$

Calibrate completely, access tested light wave components and parts, the measuring transmission loss value OS of tested light wave components and parts _11Mwith reflection characteristic test value OS _21Mexpression formula be:

$S_{31M}=\frac{C}{R_1}=e_{00}+\frac{e_{10}*e_{01}}{1-e_{41}*e_{14}}*O{S}_{11}---\left(5\right)$

$S_{21M}=\frac{B}{R_1}=e_{31}+\frac{e_{10}*e_{32}}{1-e_{35}*e_{53}}*O{S}_{21}---\left(6\right)$

Test result after calibration is:

${\mathrm{OS}}_{11}=\frac{S_{31M}-M_1}{M_3-M_1}---\left(7\right)$

${\mathrm{OS}}_{21}=\frac{S_{21M}-M_2}{M_4-M_2}---\left(8\right).$

The invention has the beneficial effects as follows:

(1) vector network analyzer internal error and photoelectron modular converter error are calibrated simultaneously;

(2) improve phase place and amplitude measuring accuracy simultaneously;

(3) improve platform test dynamic range.

Accompanying drawing explanation

In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, to the accompanying drawing of required use in embodiment or description of the Prior Art be briefly described below, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skills, do not paying under the prerequisite of creative work, can also obtain according to these accompanying drawings other accompanying drawing.

Fig. 1 is the test philosophy figure of calibration steps that the present invention is based on the light wave component testing of vector network analyzer;

Fig. 2 is the light wave component testing error model figure based on vector network analyzer;

Fig. 3 is the light wave component testing error equivalent model figure based on vector network analyzer;

Fig. 4 is the vacant error model figure of E/O back end test port;

Fig. 5 is E/O back end test port access light total reflection meter error model figure;

Fig. 6 is the test port error model figure that is directly connected.

Embodiment

Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is clearly and completely described, obviously, described embodiment is only the present invention's part embodiment, rather than whole embodiment.Embodiment based in the present invention, those of ordinary skills, not making the every other embodiment obtaining under creative work prerequisite, belong to the scope of protection of the invention.

Straight-through calibration has only been carried out in light wave components and parts based on vector network analyzer calibration at present.The present invention uses vector network analyzer and optoelectronic converter part to build light wave analysis platform, sets up its test error model, provides a kind of method that precision is higher, can calibrate vector network analyzer inside and optoelectronic module error simultaneously.

The present invention is based on vector network analyzer light wave component testing calibration steps test philosophy as shown in Figure 1.The signal source of vector network analyzer VNA produces test signal, uses a coupling mechanism drive test trial signal to the VNA receiver R1 passage that is coupled to receive.Another drive test trial signal enters electrooptic conversion module E/O, and the light signal of E/O output loads on tested photoelectric component DUT.The signal transmission of tested photoelectric component is converted to electric signal by photoelectric conversion module O/E, by VNA receiver B passage, is received.The reflected signal of tested photoelectric component is received by receiver C-channel after another photoelectric conversion module O/E is converted to electric signal through circulator.Vector network analysis internal signal sources He Yi road local vibration source Lo is produced by same frequency reference; Modulation source provides modulation signal for electrooptic conversion module E/O; Demodulation source provides restituted signal for photoelectric conversion module O/E.Above-mentioned coupling mechanism also can use electric bridge to substitute.

Vector network analyzer VNA comprises 4 ports, and VNA of the present invention has been used wherein three ports, and choosing of port one, port 2 and port 3 is randomness, not as limiting the scope of the invention.Port one has been used R1 receiver, is R1 passage; Port 2 has been used receiver B, is B passage; Port 3 has been used receiver C, is C-channel.

Based on vector network analyzer light wave component testing error model as shown in Figure 2, port one microwave error comprises directional error EDF, transmission tracking error ESTF, source mismatch error ESF and skin tracking error E SRF.

In E/O switching device, because light does not exist matching problem, reflection of light echo does not cause the variation of E/O microwave incoming signal, so E/O switching device model comprises the directional error EEODF of electric light converting transmission coefficient ESOTF and E/O device microwave end.

In O/E switching device model, because light does not exist matching problem, without transmitting optical echo, so its model comprises the transmission coefficient EOSTF of O/E device, the matching error EOESF of O/E device and an inner microwave matching error.The microwave matching error of O/E inside is exported without light wave, is therefore a closed circuit.

The microwave error of port 2 and port 3 comprises receiver transmission tracking error ERTF and receiver mismatches error E LF.

There is not matching problem in tested light wave device, and O/E device no reflection events light, and therefore tested light wave device model only includes transmission error coefficient OS ₂₁with reflection error coefficient OS ₁₁two parameters.

The circulator degree of coupling is very high, can think that the reflected light of tested light wave device all reflects to enter another O/E device.

Take tested light wave device DUT as test plane, the microwave error of the error of E/O and O/E device and port one, port 2, port 3 is merged, input end is used the inner receiver C/R1 of VNA, transmit port is VNA receiver B/R1, now can simplify the light wave component testing error model obtaining based on VNA, as shown in Figure 3.

Calibration process comprises the following steps:

Step (a), will test E/O converter rear end vacant.The now light of E/O converter output enters in air, and no reflection events, is equivalent to test port in microwave and connects desired load, and now error model as shown in Figure 4.

Test volume S in VNA _31Mand S _21Mfor

$S_{31M}=\frac{C}{R_1}=e_{00}=M_1---\left(1\right)$

$S_{21M}=\frac{B}{R_1}=e_{31}=M_2---\left(2\right)$

Step (b), access light total reflection meter.The principle of light total reflection meter can analogy and microwave test in ideal open circuit device, its reflection error coefficient OS ₁₁=1, so error model is as shown in Figure 5.

Test volume S in VNA _31Mfor

$S_{31M}=\frac{C}{R_1}=e_{00}+\frac{e_{10}*e_{01}}{1-e_{41}*e_{14}}=M_3---\left(3\right)$

Step (c), is directly connected E/O converter back end test port with O/E converter head end test port, now can be analogous to leading directly in microwave test, transmission error coefficient OS ₂₁=1, so error model is as shown in Figure 6.

Test volume S in VNA _21Mfor:

$S_{21M}=\frac{B}{R_1}=e_{31}+\frac{e_{10}*e_{32}}{1-e_{35}*e_{53}}=M_4---\left(4\right)$

So far calibrate complete, access device under test, as shown in Figure 3, the measuring transmission loss value OS of light wave components and parts _11Mwith reflection characteristic test value OS _21Mexpression formula be:

$S_{31M}=\frac{C}{R_1}=e_{00}+\frac{e_{10}*e_{01}}{1-e_{41}*e_{14}}*O{S}_{11}---\left(5\right)$

$S_{21M}=\frac{B}{R_1}=e_{31}+\frac{e_{10}*e_{32}}{1-e_{35}*e_{53}}*O{S}_{21}---\left(6\right)$

Therefore the test result after calibration is

${\mathrm{OS}}_{11}=\frac{S_{31M}-M_1}{M_3-M_1}---\left(7\right)$

${\mathrm{OS}}_{21}=\frac{S_{21M}-M_2}{M_4-M_2}---\left(8\right)$

In above-mentioned calibration process, the sequencing of step (a), step (b) and step (c) can be adjusted, and these conversion all should belong to the protection domain of claims of the present invention.

The present invention is based on the calibration steps of the light wave component testing of vector network analyzer, based on VNA and an electrical to optical converter and two photoelectric commutators, so system cost is lower; The present invention considers the electricity error of vector network analyzer and photoelectric commutator simultaneously, and calibration accuracy is higher, so measuring accuracy is higher; Only need make test port vacant, connect light total reflection meter and straight-throughly can complete calibration, simple to operate; Owing to being vector calibration, therefore can provide amplitude and the phase place of tested components and parts.

The foregoing is only preferred embodiment of the present invention, in order to limit the present invention, within the spirit and principles in the present invention not all, any modification of doing, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.

Claims (1)

1. the calibration steps of the light wave component testing based on vector network analyzer, it is characterized in that, the signal source of vector network analyzer produces test signal, one drive test trial signal is coupled to vector network analyzer receiver R1 passage by coupling mechanism and receives, another drive test trial signal enters electrooptic conversion module, the light signal of electrooptic conversion module output loads on tested light wave components and parts, the signal transmission of tested light wave components and parts is converted to electric signal by photoelectric conversion module, by vector network analyzer receiver B passage, received, the reflected signal of tested light wave components and parts is received by vector network analyzer receiver C-channel after circulator is converted to electric signal by another photoelectric conversion module, described receiver R1 passage is port one, and receiver B passage is port 2, and receiver C-channel is port 3,

Port one microwave error comprises directional error EDF, transmission tracking error ESTF, source mismatch error ESF and skin tracking error E SRF;

E/O switching device model comprises the directional error EEODF of electric light converting transmission error coefficient ESOTF and E/O device microwave end;

O/E switching device model comprises the transmission error coefficient EOSTF of O/E device, the matching error EOESF of O/E device and an inner microwave matching error;

The microwave error of port 2 and port 3 comprises receiver transmission tracking error ERTF and receiver mismatches error E LF;

Tested light wave device model only comprises transmission error coefficient OS ₂₁with reflection error coefficient OS ₁₁;

Take tested light wave components and parts as test plane, the microwave error of the error of E/O and O/E device and port one, port 2, port 3 is merged, input end is used the inner receiver C/R1 of vector network analyzer, transmit port is vector network analyzer receiver B/R1, simplifies the light wave component testing error model based on vector network analyzer;

Calibration process comprises:

Step (a), will test E/O converter rear end vacant, test volume S in vector network analyzer _31Mand S _21Mfor:

$S_{31M}=\frac{C}{R_1}=e_{00}=M_1---\left(1\right)$

$S_{21M}=\frac{B}{R_1}=e_{31}=M_2---\left(2\right)$

Step (b), access light total reflection meter, its reflection characteristic coefficient OS ₁₁=1, test volume S in vector network analyzer _31Mfor:

$S_{31M}=\frac{C}{R_1}=e_{00}+\frac{e_{10}*e_{01}}{1-e_{41}*e_{14}}=M_3---\left(3\right)$

Step (c), is directly connected E/O converter back end test port with O/E converter head end test port, transport property coefficient OS ₂₁=1, test volume S in vector network analyzer _21Mfor:

$S_{21M}=\frac{B}{R_1}=e_{31}+\frac{e_{10}*e_{32}}{1-e_{35}*e_{53}}=M_4---\left(4\right)$

Calibrate completely, access tested light wave components and parts, the measuring transmission loss value OS of tested light wave components and parts _11Mwith reflection characteristic test value OS _21Mexpression formula be:

$S_{31M}=\frac{C}{R_1}=e_{00}+\frac{e_{10}*e_{01}}{1-e_{41}*e_{14}}*O{S}_{11}---\left(5\right)$

$S_{21M}=\frac{B}{R_1}=e_{31}+\frac{e_{10}*e_{32}}{1-e_{35}*e_{53}}*O{S}_{21}---\left(6\right)$

Test result after calibration is:

${\mathrm{OS}}_{11}=\frac{S_{31M}-M_1}{M_3-M_1}---\left(7\right)$

${\mathrm{OS}}_{21}=\frac{S_{21M}-M_2}{M_4-M_2}---\left(8\right).$