CN105137243B - A kind of method for determining LNA degeneration power threshold and damage power threshold - Google Patents
A kind of method for determining LNA degeneration power threshold and damage power threshold Download PDFInfo
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- CN105137243B CN105137243B CN201510573741.3A CN201510573741A CN105137243B CN 105137243 B CN105137243 B CN 105137243B CN 201510573741 A CN201510573741 A CN 201510573741A CN 105137243 B CN105137243 B CN 105137243B
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Abstract
The invention discloses a kind of method for determining LNA degeneration power threshold and damage power threshold, it comprises the following steps：First, test platform is built；2nd, Injection Signal is constructed：3rd, test：(1) small signal S-parameters of testing sample are measured | S21| and noise coefficient NF, (2) persistently inject certain time to testing sample, and (3) measure testing sample after this injects | S21| and NF, (4) increase Injection Signal mean power, (2) and (3) two steps are repeated, until | S21| and untill acute exacerbation occurs for NF；4th, draw | S21| and NF is with injecting power PinThe double y-axis coordinate system curve maps for increasing and changing, therefrom extract degeneration power threshold and damage power threshold.The present invention is advantageous in that：Power injection effect is more preferable, and threshold measurement result can more reflect the anti-power level under LNA actual operating conditions；Degeneration power threshold can be obtained, meets LNA high reliability and the requirement for low noise in high sensitivity electronic equipment.
Description
Technical field
The present invention relates to a kind of method for determining microelectronic component and circuit performance parameters, and in particular to one kind measure low noise
The method for putting degeneration power threshold and damage power threshold, belongs to microelectronics technology.
Background technology
With the increasingly complexity of electromagnetic environment, microelectronic component and the threat that circuit is subject to are increasing.Microelectronic component
The susceptibility of electromagnetic pulse environment can be characterized with degeneration or damage power threshold with circuit.However, micro- electricity is available at present
The experimental method of sub- device and circuit degradation or damage threshold measure reference only has People's Republic of China's GJB《Half
Conductor device Electromagnetic pulse damage threshold experimental method》, it is (discrete the standard specifies semiconductor devices is determined with direct injection
Device, microcircuit) Electromagnetic pulse damage threshold basic skills and requirement.The standard is applied to have radiation hardening requirement
General semiconductor devices and circuit, but its experiment belongs to destructive test, and it is damage threshold to measure threshold value.
Low-noise amplifier (low noise amplifier, LNA, abbreviation LNA) is that a kind of noise coefficient is very low
Amplifier, it is generally used for radio frequency electric system front end and has in the electronic equipment of high sensitivity requirement.For LNA,
Often occurrence features degradation effect occurs before destructive damage effect under electromagnetic pulse environment, and for radio frequency electric
For system front end and the electronic equipment of high sensitivity requirement, the performance degradation of LNA also can not be ignored, but at present but
The experimental method of LNA degeneration power threshold is not determined.In addition, noise coefficient is an important indicator of LNA, control
Noise, improve signal to noise ratio for LNA amplification small-signal reduce interference it is particularly important, therefore, judge LNA damage and
Situation of change when no without reference to noise coefficient this index is extremely irrational, even if reference noise coefficient can not be by
Go to implement according to the judgment mode with performance parameter variations 50% usually used, thus need badly at present one it is rational, based on should
With demand and the criterion of statistics experience.
The content of the invention
For solve the deficiencies in the prior art, it is an object of the invention to provide one kind measure LNA degeneration power threshold and
The method of damage power threshold, the assay method can not only realize the estimation to LNA degeneration power threshold to meet low noise
High reliability demand is put, and the accuracy and reasonability of LNA damage power threshold measure can be improved, while is also had
The advantages of test process is simple.
In order to realize above-mentioned target, the present invention adopts the following technical scheme that：
A kind of method for determining LNA degeneration power threshold and damage power threshold, it is characterised in that including following step
Suddenly：
First, test platform is built：
Utilize signal source, pulse signal generator, power amplifier, adjustable attenuator, power meter, noise analyzer, arrow
Amount Network Analyzer and directional coupler build test platform,
Signal is produced by signal source, the signal pulsed signal generator forms pulse signal, and the pulse signal is carried out
Modulation obtains pulse modulated carrier signal, pulse modulated carrier signal is amplified through radio-frequency power amplifier, and this is believed
Number connection adjustable attenuator, then be connected to by directional coupler on power meter to observe Injection Signal power, finally by signal
Testing sample input is accessed, while passes through switch in parallel noise analyzer and vector net in testing sample input and output end
Network analyzer is used to measure the front and rear LNA small-signal behaviour parameter of power injection；
2nd, Injection Signal pattern is constructed, test parameter is set：
The Injection Signal of construction is the periodic modulation rectangular wave pulse signal of sine wave carrier；
Pulse signal generator is arranged to recurrent pulses output, sets pulse signal generator defeated according to testing sample
Pulse width τ, pulse period T and the pulse number n gone out, while the carrier frequency f of setting signal source output, said carrier frequency
Rate f keeps carrier frequency f constant in the range of testing sample working band in test process；
3rd, test：
(1) small signal S-parameters of testing sample, are measured with vector network analyzer and noise analyzer | S21| and noise system
Number NF, and make respective record；
(2) Injection Signal mean power, is set by adjusting radio-frequency power amplifier and adjustable attenuator, to testing sample
Persistently inject certain time interval Td=nT, and record this injecting power value；
(3) after, this injection terminates, this is only measured using vector network analyzer and noise analyzer by switching switching
The small signal S-parameters of testing sample after secondary injection | S21| and noise coefficient NF, and note down；
(4), increase Injection Signal mean power is injected next time, and (2) and (3) two step is repeated, until
Measure obtained small signal S-parameters | S21| and untill acute exacerbation occurs for noise coefficient NF, each group of testing sample is used for power
The maximum number of repetitions of injection is no more than 4 times；
4th, degeneration power threshold and damage power threshold are extracted：
(1) small signal S-parameters, are drawn using data processing software | S21| and noise coefficient NF is with injecting power PinIncrease
Big and change double y-axis coordinate system curve maps；
(2) two curves, are observed, during injecting power stepping increases, will meet that noise coefficient NF is disliked for the first time
Corresponding injecting power is designated as degeneration power threshold when changing more than 0.4dB, will meet small signal S-parameters | S21| reduce by 50% with
Injecting power corresponding when deteriorating to one condition of 10dB any of the above upper or noise coefficient NF is designated as damage power threshold.
Foregoing assay method, it is characterised in that also include in foregoing test platform：First isolator and the second isolation
Device, the pulse signal that pulse signal generator is formed first enter power amplifier again through the first isolator, and testing sample output end is led to
Cross the second isolator and connect load.
Foregoing assay method, it is characterised in that also include in foregoing test platform：Circulator, the connection of aforementioned toroidal device
Between adjustable attenuator and directional coupler.
Foregoing assay method, it is characterised in that in step 3, power stepping increasing degree is set to 1dB.
Foregoing assay method, it is characterised in that in step 3, small signal S-parameters | S21| and noise coefficient NF occurs
The standard of acute exacerbation is：Small signal S-parameters | S21| more than 50% is reduced, noise coefficient NF deteriorates to more than 10dB.
The present invention is advantageous in that：
(1) assay method of the invention using pulse modulated carrier signal as Injection Signal pattern, and by carrier wave
Frequency setting is the frequency values in LNA working band so that power injection effect is more preferable, and threshold measurement result can more reflect
The anti-power level gone out under LNA actual operating conditions；
(2) assay method of the invention is referred to using noise coefficient, can obtain LNA degeneration power threshold, is met
Current LNA high reliability and the requirement for low noise in electronic system front end and high sensitivity electronic equipment；
(3) assay method of the invention, which adds noise coefficient to the measure of damage power threshold and deteriorates this conduct, sentences
According to combining the concrete application background of LNA conscientiously, and measuring accuracy is greatly improved.
Brief description of the drawings
Fig. 1 is the FB(flow block) of the assay method of the present invention；
Fig. 2 is the composition schematic diagram of test platform in assay method of the invention；
Fig. 3 is the Injection Signal pattern diagram constructed in the assay method of the present invention；
Fig. 4 is the small signal S-parameters that the assay method of the present invention obtains | S21| and noise coefficient NF is with injecting power Pin
The double y-axis coordinate system curve maps for increasing and changing.
Embodiment
To become apparent from objects, features and advantages of the present invention and it can be readily appreciated that below in conjunction with the drawings and specific embodiments
Make specific introduce to the present invention.
The method of reference picture 1, measure LNA degeneration power threshold of the invention and damage power threshold includes following step
Suddenly：
First, test platform is built
First, the composition of the test platform is introduced.
Reference picture 2, the test platform mainly by signal source, pulse signal generator, power amplifier, adjustable attenuator,
Directional coupler, power meter, noise analyzer and vector network analyzer etc. are built.
In order to avoid the influence of interference signal, test platform also includes：First isolator and the second isolator, wherein, the
One isolator is connected between pulse signal generator and power amplifier, and it can avoid interacting between front and rear instrument；
Second isolator is connected to testing sample output end between load, and it can absorb the power output of testing sample, and ensure
Signal interference of the testing sample from coming from absorbing load.
In order to protect instrument also to include from the damage of reflected microwave pulse, test platform：Circulator.Circulator is connected to
Between adjustable attenuator and directional coupler, it can protect prime instrument from the damage of reflected microwave pulse.
Next, introduce the job order of the test platform.
Reference picture 2, a certain frequency signal is produced by signal source first, the signal pulsed signal generator forms pulse letter
Number, then the pulse signal is modulated to obtain pulse modulated carrier signal, by pulse modulated carrier signal through first
Isolator and radio-frequency power amplifier amplification, produce the pulse-modulated signal with higher power density, the high power after amplification
The impulse modulation of the density signal is injected into testing sample input after adjustable attenuator, circulator and directional coupler successively
End, while be connected on directional coupler and also have power meter, power meter is put down to monitor the reality being injected into testing sample
Equal power, testing sample output end connect load by the second isolator.The input and output end of testing sample are by switching simultaneously
Connection noise analyzer and vector network analyzer, noise analyzer and vector network analyzer inject to measure power each time
Front and rear LNA small-signal behaviour parameter.
2nd, Injection Signal pattern is constructed, test parameter is set
Injection Signal pattern as shown in Figure 3 is constructed, is the characteristics of the Injection Signal pattern：The periodicity of sine wave carrier
Modulated square wave pulse signal.
Realize comprising the following steps that for the Injection Signal pattern shown in Fig. 3：
1st, pulse signal generator is arranged to recurrent pulses output, pulse signal generator is set according to testing sample
Pulse width τ, pulse period T and the pulse number n of output.
2nd, according to the carrier frequency f in testing sample setting signal source, carrier frequency f is in testing sample working band scope
It is interior, and keep carrier frequency f constant in test process.
3rd, test
1st, the small signal S-parameters of testing sample are measured with vector network analyzer | S21|, measured with noise analyzer to be measured
The noise coefficient NF of sample, record the small signal S-parameters of testing sample | S21| and noise coefficient NF.
2nd, by adjusting the power output of radio-frequency power amplifier and the attenuation of adjustable attenuator, Injection Signal is adjusted
Mean power, certain time interval T is persistently injected to testing sampled=nT, and this reality injected is recorded according to power meter
Injecting power value.
3rd, after this injection terminates, this is only measured using vector network analyzer and noise analyzer by switching switching
The small signal S-parameters of testing sample after injection | S21| and noise coefficient NF, and note down.
4th, increase Injection Signal mean power is injected next time, and power stepping increasing degree is set to 1dB, is repeated
2nd and the 3rd liang of step, until measuring obtained small signal S-parameters | S21| and acute exacerbation (small signal S ginseng occurs for noise coefficient NF
Number | S21| more than 50% is reduced, noise coefficient NF deteriorates to more than 10dB) untill.
If acute exacerbation does not occur yet for sample after the continuous stepping of injecting power increases by 4 times, one group of testing sample is changed, i.e.,
The maximum number of repetitions that each group of testing sample is used for power injection is no more than 4 times, is damaged with avoiding being repeatedly injected the accumulation brought
Hinder effect.
4th, degeneration power threshold and damage power threshold are extracted
1st, joined according to the S recorded after the injecting power and injection that power injection experimentses are recorded each time in the 3rd step
Number and noise coefficient, small signal S-parameters are drawn using data processing software | S21| and noise coefficient NF is with injecting power PinIncrease
Big and change double y-axis coordinate system curve maps.
2nd, two curves are observed, during injecting power stepping increases, will meet that noise coefficient NF deteriorates for the first time
Corresponding injecting power is designated as degeneration power threshold during more than 0.4dB, will meet small signal S-parameters | S21| reduce by more than 50%
Or noise coefficient NF injecting powers corresponding when deteriorating to one condition of 10dB any of the above are designated as damage power threshold.
In order to be better understood upon technical scheme, we using certain model GaAs microwave LNA as
Example, further illustrate the method for determining its degeneration power threshold and damage power threshold.
The normal bias voltage of the model GaAs microwave LNA is 2V, quiescent current 10mA, in its normal work
Frequency of heart is f0。
The first step, according to Fig. 2 connection experimental instrument and equipments, build test platform.
Second step, Injection Signal pattern and parameter are determined, and carry out the setting of signal source and pulse signal generator, specifically
It is as follows：
(1) it is recurrent pulses output to set pulse signal generator, and the pulse width of output is 60 μ s, and the pulse period is
3ms, 10 minutes impulse action duration；
(2) the carrier frequency f of setting signal source output is LNA normal work centre frequency f0。
3rd step, carry out power injection experimentses, the performance number and the acquisition small letter of testing sample of record power injection each time
Number parameter, it is specific as follows：
(1) small signal S-parameters of sample are measured with vector network analyzer before the 1st power injects | S21| it is
34.5dB, the noise coefficient NF that sample is measured with noise analyzer is 0.7dB；
(2) constantly increase Injection Signal power, and record the small letter of sample after injecting power value and injection each time
Number parameter value；
The small signal S-parameters of sample are measured after (3) the 35th power injections | S21| it is 30.4dB, noise coefficient NF is
2dB；
The small signal S-parameters of sample are measured after (4) the 36th power injections | S21| it is -21dB, noise coefficient NF is
29dB, now small signal S-parameters | S21| reduce more than 50%, and noise coefficient NF deteriorates to more than 10dB, judges sample
Damage.
4th step, degeneration power threshold and damage power threshold are extracted, it is specific as follows：
(1) according to the small-signal parameter measured after the value of injecting power each time recorded in previous step and injection, draw
Obtain double y-axis coordinate system curve maps shown in Fig. 4；
(2) figure 4, it is seen that when power is P1Signal injection after the NF of sample deteriorate to 1.7dB, it is and unimplanted
It is 1dB to deteriorate amplitude compared to it before signal, and NF deteriorates amplitude for the first time more than 0.4dB, takes P1For the degeneration power of LNA
Threshold value；
The performance number of (3) (n+1)th power injections is P2, the small signal S-parameters of sample after injection | S21| deteriorate to-
21dB, noise coefficient NF deteriorate to 29dB, small signal S-parameters | S21| reduce more than 50%, and noise coefficient NF deteriorates to 10dB
More than, take P2For the damage power threshold of LNA.
As can be seen here, assay method of the invention uses pulse modulated carrier signal as Injection Signal pattern, and
Carrier frequency is set as the frequency values in LNA working band so that power injection effect is more preferable, and threshold measurement result is more
The anti-power level under LNA actual operating conditions can be reflected.
In addition, the assay method of the present invention is referred to using noise coefficient, LNA degeneration power threshold can be obtained, it is full
Foot current LNA high reliability and the requirement for low noise in electronic system front end and high sensitivity electronic equipment.
Meanwhile assay method of the invention adds noise coefficient to the measure of damage power threshold and deteriorates this conduct
Criterion, combines the concrete application background of LNA conscientiously, and measuring accuracy is greatly improved.
It should be noted that the invention is not limited in any way for above-described embodiment, it is all to use equivalent substitution or equivalent change
The technical scheme that the mode changed is obtained, all falls within protection scope of the present invention.
Claims (5)
- A kind of 1. method for determining LNA degeneration power threshold and damage power threshold, it is characterised in that comprise the following steps：First, test platform is built：Utilize signal source, pulse signal generator, radio-frequency power amplifier, adjustable attenuator, power meter, noise analyzer, arrow Amount Network Analyzer and directional coupler build test platform,Signal is produced by signal source, the signal pulsed signal generator forms pulse signal, and the pulse signal is modulated Pulse modulated carrier signal is obtained, pulse modulated carrier signal is amplified through radio-frequency power amplifier, and the signal is connected Adjustable attenuator is connect, then is connected to by directional coupler on power meter to observe Injection Signal power, finally accesses signal Testing sample input, while pass through switch in parallel noise analyzer and vector network point in testing sample input and output end Analyzer is used to measure the front and rear LNA small-signal behaviour parameter of power injection；2nd, Injection Signal pattern is constructed, test parameter is set：The Injection Signal of construction is the periodic modulation rectangular wave pulse signal of sine wave carrier；Pulse signal generator is arranged to recurrent pulses output, sets what pulse signal generator exported according to testing sample Pulse width τ, pulse period T and pulse number n, while the carrier frequency f, the carrier frequency f of setting signal source output In the range of testing sample working band, and keep carrier frequency f constant in test process；3rd, test：(1) small signal S-parameters of testing sample, are measured with vector network analyzer and noise analyzer | S21| and noise coefficient NF, and make respective record；(2) Injection Signal mean power, is set by adjusting radio-frequency power amplifier and adjustable attenuator, testing sample is continued Inject certain time interval Td=nT, and record this injecting power value；(3) after, this injection terminates, this note is only measured using vector network analyzer and noise analyzer by switching switching Enter the small signal S-parameters of rear testing sample | S21| and noise coefficient NF, and note down；(4), increase Injection Signal mean power is injected next time, and (2) and (3) two step is repeated, until measurement Obtained small signal S-parameters | S21| and untill acute exacerbation occurs for noise coefficient NF, each group of testing sample injects for power Maximum number of repetitions be no more than 4 times；4th, degeneration power threshold and damage power threshold are extracted：(1) small signal S-parameters, are drawn using data processing software | S21| and noise coefficient NF is with injecting power PinIncrease and become The double y-axis coordinate system curve maps changed；(2) two curves, are observed, during injecting power stepping increases, will meet that noise coefficient NF deteriorates for the first time Corresponding injecting power is designated as degeneration power threshold during more than 0.4dB, will meet small signal S-parameters | S21| reduce by more than 50% Or noise coefficient NF injecting powers corresponding when deteriorating to one condition of 10dB any of the above are designated as damage power threshold.
- 2. the method for measure LNA degeneration power threshold according to claim 1 and damage power threshold, its feature exist In also including in the test platform：First isolator and the second isolator, the pulse signal that pulse signal generator is formed are first Enter radio-frequency power amplifier again through the first isolator, testing sample output end connects load by the second isolator.
- 3. the method for measure LNA degeneration power threshold according to claim 1 or 2 and damage power threshold, its feature It is, also includes in the test platform：Circulator, the circulator are connected between adjustable attenuator and directional coupler.
- 4. the method for measure LNA degeneration power threshold according to claim 1 and damage power threshold, its feature exist In in step 3, power stepping increasing degree is set to 1dB.
- 5. the method for the measure LNA degeneration power threshold and damage power threshold according to claim 1 or 4, its feature It is, in step 3, small signal S-parameters | S21| and noise coefficient NF occur acute exacerbation standard be：Small signal S-parameters | S21| more than 50% is reduced, noise coefficient NF deteriorates to more than 10dB.
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| CN109188234B (en) * | 2018-09-18 | 2020-12-29 | 中国工程物理研究院应用电子学研究所 | Automatic integrated device for multi-path high-power microwave injection and S parameter measurement |
| CN109298296B (en) * | 2018-11-12 | 2020-01-24 | 西安电子科技大学 | Damage grading equivalent modeling and simulation method for radio frequency link under strong electromagnetic pulse injection |
| CN114264935A (en) * | 2021-12-22 | 2022-04-01 | 深圳飞骧科技股份有限公司 | In-chip interference test method and in-chip interference test system |
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