CN101413987A - Automatic test system of sound surface filtering device - Google Patents

Abstract

An automatic measuring system for a surface acoustic wave filter device is composed of a measurement fixture, a network analyzer, a GPIB-PCI switching circuit, a computer, a human-machine interface, and an I/O interface circuit which are connected. The filter device is inserted in the measurement fixture, and the network analyzer scans the filter device to acquire testing parameters; the acquired testing parameters are output by a GPIB interface of the network analyzer and read in the computer by the GPIB-PCI switching circuit; the testing of the filter device is finished by an algorithm which is built in the computer; and finally the testing result is output and stored, and the computer automatically finishes the output of a grading signal by the I/O interface circuit. The setting of the network analyzer can be changed by the human-machine interface, or the testing can be directly finished in the computer by selecting the testing parameters of the surface acoustic wave filter device. The automatic measuring system can simultaneously measure a plurality of parameters without personnel participation during the data testing for once, and has the functions of parameter setting, data analysis, data storage, diagram generation and printing. The grading output signal is provided to control a grading mechanism to grade products.

Description

Automatic test system of sound surface filtering device

Technical field

The present invention relates to the parameter of acoustic surface wave filter device is tested test macro with performance evaluation automatically.

Background technology

Acoustic surface wave filter device is referred to as sound surface filtering device again, because it has characteristics such as antijamming capability is strong, volume is little, noiselessness, market demand is bigger, and description is various, and its manufacturer is also more.The main means of testing of acoustic surface wave filter device is to adopt the network analyzer that is connected with measured material by manually carrying out parameter testing at present, network analyzer is by swept signal source, detecting device and receiver three parts connect to form, in test process, reflection characteristic or transport property to device under test under the control of the microprocessor that is installed on detecting device inside scan, the collecting test parameter, the parameter that the tester gathers according to network analyzer, manually the parameter quality is comprehensively judged, interference and uncertain factor are bigger, can reduce the fiduciary level of test, and manual testing's efficient is low, labour intensity is big, far can not satisfy the detection demand of filtering device high-quality and high-efficiency.Network analyzer has only the function of acquisition parameter simultaneously, lacks the analytic function to supplemental characteristic, can not be applicable to the automatic monitoring to the sound surface filtering device quality.

The content of invention

The applicant at above-mentioned employing network analyzer by manually carrying out the problem that parameter testing exists, having carried out research improves, a kind of multi-functional automatic test system of sound surface filtering device is provided, in the process of test parameter, after the network analyzer collecting test parameter, do not need the parameter of gathering to be carried out analysis and judgement and parameter testing, and once can measure a plurality of parameters simultaneously with artificial.

Technical scheme of the present invention is as follows:

Measured material is used for the clamping device under test;

The network analyzer that is connected with measured material, connect to form by swept signal source, detecting device and receiver three parts, reflection characteristic or transport property to device under test under the control of the microprocessor that is installed on detecting device inside scan, the collecting test parameter, and the result that will scan (test parameter of collection) is by the gpib interface output of network analyzer;

Also comprise:

The GPIB-PCI change-over circuit is connected with the gpib interface of network analyzer, and gpib bus output is converted to pci bus output;

The row format conversion of going forward side by side of computing machine, the data of importing the output of described GPIB-PCI change-over circuit, and finish test to device detection scheme to be measured, output and store test results by built-in algorithms;

The man-machine interface that is connected with fanout is used to show test results and by user's measurement requirement test parameter is set;

The I/O interface circuit that is connected with fanout is used for the stepping signal of described test result is carried out interface output.

Further:

Described man-machine interface can be carried out the test parameter setting to described network analyzer by user's measurement requirement.

Perhaps described man-machine interface is carried out the test parameter setting by user's measurement requirement, each test event is assigned under the different data layouts, form in the corresponding testing scheme input computing machine and directly test, and show the test result of computing machine in man-machine interface.

Technique effect of the present invention is:

The present invention imports computing machine according to the test parameter of network analyzer collection by change-over circuit, finishes the test of parameter automatically by computing machine, and judges the quality quality of SAW (Surface Acoustic Wave) device.Do not need human brain to participate in judging in the data test, avoided the accidental error that artificial participation causes, effectively improved the fiduciary level of measurement result, easy to detect quick, the Measuring Time of individual devices is no more than 1 second.Can also change the setting of network analyzer by man-machine interface, perhaps select the test parameter of SAW (Surface Acoustic Wave) device, directly in computing machine, finish test by man-machine interface.The present invention once can measure a plurality of parameters simultaneously, has parameter setting, data analysis, data preservation, chart generation and printing function, and the stepping output signal is arranged, and the controllable sub gear mechanism carries out stepping to product.

Description of drawings

Fig. 1 is a frame assumption diagram of the present invention.

Fig. 2 is man-machine interface figure of the present invention, the test parameter of selecting shown in the figure, parameter value and the testing scheme of being formed.

Embodiment

Below in conjunction with accompanying drawing the specific embodiment of the present invention is described further.

Fig. 1 is a frame assumption diagram of the present invention.As shown in Figure 1, the present invention includes:

Measured material 1 is used for the clamping device under test;

The network analyzer 2 that is connected with measured material 1, it is connected to form by swept signal source, detecting device and receiver three parts, reflection characteristic or transport property to device under test under the control of the microprocessor that is installed on detecting device inside scan, the collecting test parameter, and the result that will scan (test parameter of collection) is by the gpib interface output of network analyzer 2;

The present invention also comprises:

GPIB-PCI change-over circuit 3 is connected with the gpib interface of network analyzer 2, and gpib bus output is converted to pci bus output;

The row format conversion of going forward side by side of computing machine 4, the data of importing the output of described GPIB-PCI change-over circuit, and finish test to device detection scheme to be measured, output and store test results by built-in algorithms;

With the man-machine interface 5 that computing machine 4 output terminals are connected, be used to show test results and by user's measurement requirement test parameter be set: described man-machine interface 5 can be carried out the test parameter setting to described network analyzer by user's measurement requirement; Perhaps described man-machine interface 5 is carried out the test parameter setting by user's measurement requirement, each test event is assigned under the different data layouts, form in the corresponding testing scheme input computing machine 4, in computing machine, directly carry out SAW (Surface Acoustic Wave) device is tested, and show the test result of computing machine 4 in man-machine interface 5;

With the I/O interface circuit 6 that computing machine 4 output terminals are connected, be used for the stepping signal of described test result is carried out interface output.

When the present invention works, measured device is inserted in the test fixture 1, automatically the reflection characteristic or the transport property of device are scanned by network analyzer 2, the result of scanning is by gpib bus (the General Purpose Interface Bus of network analyzer 2, general purpose interface bus, IEEE488.2) interface socket output, pass through GPIB-PCI (PCI then, Peripheral Component Interconnection, the peripheral component interconnection bus) change-over circuit 3 reads in the internal memory of computing machine 4, format conversion through computing machine 4 inside, generate required measurement data, and then finish the test of scheme by built-in algorithm, output and store test results at last, and have chart to generate and printing function; The test result of output shows that on man-machine interface 5 computing machine is finished the output of stepping signal in the test result by I/O interface circuit 6, and a control minute gear mechanism carries out stepping to product.

Be the speed of raising data transfer, the The data binary transfer of native system, transmitting content is formative polar coordinates (POLAR) data.Is LOG MAG (Bode diagram), PHASE (phase diagram), DELAY required data layouts such as (group delay figure) in computing machine 4 inside with polar coordinates (POLAR) Data Format Transform, thereby the part that has realized instrument is virtual, has reduced the degree of dependence of system to network analyzer.The calculating formula of Data Format Transform is as follows:

LOG MAG, its data source is the POLAR formatted data that network analyzer passes over,

$L_i=20*\log \left(\sqrt{{\mathrm{real}}_i^2+{\mathrm{image}}_i^2}\right)$

Real and image are respectively the real part and the imaginary part of former POLAR formatted data in the formula, down together.

PHASE, its data source is the POLAR formatted data that network analyzer passes over,

$P_i=a\tan 2({\mathrm{image}}_i,{\mathrm{real}}_i)\frac{180}{\mathrm{\π}}$

DELAY, its data source is the PHASE formatted data after transforming,

u _i＝P _i+1-P _i

$v_i=\left\{\begin{array}{cc}{u}_i-360& u_i>180\\ u_i+360& u_i<-180\end{array}\right.$

$D_i=\frac{v_i}{(P_{i+1}-P_i)\&times;{10}^6}\&CenterDot;\frac{\mathrm{\&pi;}}{180}\&CenterDot;\frac{1}{2\mathrm{\&pi;}}=\frac{v_i}{(P_{i+1}-P_i)\&times;{10}^6}\&CenterDot;\frac{1}{360}$

Above calculating formula is known computing method.

Fig. 2 is man-machine interface figure of the present invention, the test parameter of selecting shown in the figure, parameter value and the testing scheme of being formed.

As shown in Figure 2, the content that " setting of network analysis instrument parameter " hurdle can be provided with comprises: centre frequency, sweep bandwidth, nominal frequency, number of scan points, measurement kind, test mode, measurement parameter and measurement passage, and mean filter, smoothing processing option are arranged, it is consistent with the content of the required setting of being adopted of network analyzer that it is provided with content.

Among Fig. 2, the setting that can measure, stop and resetting in " operation " hurdle, and (the continuous coverage pattern then is artificial measurement pattern if do not choose this can to select to adopt the machine measurement, whenever press device of one-shot measurement) and select saving result, and show stepping information.Described stepping information comprises the total number of measuring element, and according to Grade A, goods of inferior quality and underproof device number that the result that basic parameter is measured divides, finishes stepping work.

Among Fig. 2, the basic parameter measurement comprises: centre frequency, insertion loss, passband fluctuation, group delay GD, group delay fluctuation GDV and stopband loss.Can increase test event by the interpolation button of below, " basic parameter measurement " hurdle or delete above-mentioned test event.Each test event is pressed classifying requirement and is shown many group measurement results.The measuring principle of each parameter is as follows:

Centre frequency: this test event is the test event under the LOG MAG data layout.Nominal frequency F at first measures in system in the measuring process _rThe decay L at place _r, and then measure L _rThe last lower limiting frequency of-3 place's bandwidth, and ask the measured value of the average of the two as centre frequency.

Insert loss: this test event is the test event under the LOG MAG data layout.For the intermediate frequency device, nominal frequency F will measure in system _rThe pad value L at place _r, and with its measured value as the insertion loss; For high-frequency element, minimal attenuation value L in the additional bandwidth scope will search in system _Min, and with its measured value as the insertion loss.

Passband fluctuation: this test event is the test event under the LOG MAG data layout.In the measuring process, the minimal attenuation point L in the wave zone wide region will search in system _MinWith maximum attenuation point L _Max, and with L _Max-L _MinMeasured value as passband fluctuation.

Group delay GD: this test event is the test event under the DELAY data layout.In the measuring process, the average of all some group delays in the additional bandwidth scope will be calculated by system, with its measured value as group delay GD.

Group delay fluctuation GDV: this test event is the test event under the DELAY data layout.In the measuring process, the minimum group delay D in the additional bandwidth scope will search in system _MinWith maximum cluster time-delay D _Max, with D _Max-D _MinMeasured value as group delay fluctuation GDV.

Stopband loss: this test event is the test event under the LOG MAG data layout.In the measuring process, the maximum attenuation point L in the stopband will search in system _Max, for high-frequency element, system is with L _MaxMeasured value as stopband loss; For the intermediate frequency device, system is with L _Max-L _rMeasured value (L as stopband loss _rBe reference frequency F _rThe decay at place).

All the other test events comprise: N-DB bandwidth measurement, Waviness measurement, particular point group delay are measured and the particular point attenuation measurement.Each test event all can be by the interpolation button settings user input values of corresponding column below.The measuring principle of each parameter is as follows:

The N-DB bandwidth measurement: this test event is the test event under the LOG MAG data layout.In the measuring process, L will measure in system _r+ L _Input(L _InputBe user input values) bandwidth located, and with its measured value as the N-DB bandwidth.

Waviness measurement: this test event is the test event under the LOG MAG data layout.The smoothness of its main detection means.In the measuring process, system will scan all the crest L in the specific bandwidth _HWith trough L _L, and then the difference of adjacent peaks and trough judged, if L _H-L _LThen count greater than setting value.Total number that system will add up is as the measured value of Waviness measurement.

The particular point group delay is measured: with user's incoming frequency F _InputThe group delay D at place is the systematic survey value, and it is the test event under the DELAY data layout.

Particular point attenuation measurement: with user's incoming frequency F _InputThe pad value L at place is the systematic survey value, and it is the test event under the LOG MAG data layout.

Above test event is according under three the different data layouts of LOG MAG, PHASE, DELAY that require separately to be assigned to, carry out the conversion of data layout by the aforementioned calculation formula, calculate according to measuring principle separately then, its built-in algorithms is all marked the standard implementation of Q/320211DKW01-2006 according to enterprise, and is integrated in the computing machine 4.Among Fig. 1, block diagram 1 all adopts prior art to the hardware in the block diagram 6, and block diagram 2 to the software in the block diagram 6 is all write by prior art.

Claims (3)

1. automatic test system of sound surface filtering device comprises:

Measured material (1) is used for the clamping device under test;

The network analyzer (2) that is connected with measured material (1), connect to form by swept signal source, detecting device and receiver three parts, reflection characteristic or transport property to device under test under the control of the microprocessor that is installed on detecting device inside scan, and the result that will scan is by the gpib interface output of network analyzer (2);

It is characterized in that also comprising:

GPIB-PCI change-over circuit (3) is connected with the gpib interface of network analyzer (2), and gpib bus output is converted to pci bus output;

The row format conversion of going forward side by side of computing machine (4), the data of importing described GPIB-PCI change-over circuit (3) output, and finish test to device detection scheme to be measured, output and store test results by built-in algorithms;

With the man-machine interface (5) that computing machine (4) output terminal is connected, be used to show test results and test parameter be set by user's measurement requirement;

With the I/O interface circuit (6) that computing machine (4) output terminal is connected, be used for the stepping signal of described test result is carried out interface output.

2. automatic test system of sound surface filtering device as claimed in claim 1 is characterized in that: described man-machine interface (5) is carried out the test parameter setting by user's measurement requirement to described network analyzer (2).

3. automatic test system of sound surface filtering device as claimed in claim 1, it is characterized in that: described man-machine interface (5) is carried out the test parameter setting by user's measurement requirement, each test event is assigned under the different data layouts, form in the corresponding testing scheme input computing machine (4) and directly test, and show the test result of computing machine (4).

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