High-precision and high-speed switching time testing method, system and device for radio frequency switches

Abstract

The present invention relates to a switching time test method, system and equipment for a high-precision and high-speed radio frequency switch. The test cycle is first set according to the characteristics of the tested device, and then the measured value of the control voltage at each sampling moment and the measured value of the radio frequency signal voltage passing through the switch are collected by a real-time oscilloscope, and the collected radio frequency signal is enveloped and calculated. Then, according to the conduction characteristics of the radio frequency switch, the data of a complete test cycle is screened out from the collected data, and then the maximum stable voltage center moment of the radio frequency signal is obtained, the maximum stable voltage value of the radio frequency signal is calculated, and then the key moment of the switching time is obtained, and finally the switching time is calculated according to the key moment and the result is output. The present invention cooperates with a real-time oscilloscope and adopts an automatic test algorithm for measurement, so that the radio frequency time test of the radio frequency switch can be automated, stable, high-speed and accurate. It has the advantages of wide application range, high test efficiency and high measurement accuracy.

Description

Technical Field

[0001] The present invention relates to the field of radio frequency switch testing, and in particular to a switching time testing method, system and device for a radio frequency switch with high precision and high speed. Background Art

[0002] Radio frequency switch (RF Switch for short) is an extremely common and widely used RF device in the field of RF communication. In RF communication and test links, it is used for communication channel switching, transceiver status switching and other scenarios. RF switches are widely used in many fields such as the Internet of Things, small base stations, test instruments, radar, Wi-Fi and RFID. The main function of an RF switch is to receive input RF signals and transmit the input signals from the input port to the output port according to the specified conduction path. Different RF link environments require different RF switches.

[0003] The switching time of an RF switch product refers to the time required for the switch to change from the "on" state to the "off" state and from the "off" state to the "on" state.

[0004] There are two main physical quantities related to the switching time, one is the control voltage of the RF switch, and the other is the RF signal in the RF switch.

[0005] The control voltage is a direct current signal (DC) on the RF switch. There are two conduction control methods: rising conduction and falling conduction. Rising conduction means that the switch is turned on when the control voltage rises; correspondingly, when the control voltage drops, the switch is turned off. Falling conduction means that the switch is turned on when the control voltage drops; correspondingly, when the control voltage rises, the switch is turned off.

[0006] The switching time of the RF switch mainly tests the following four items:

[0007] 1. On Time (or tOn): It measures the time interval from when the control voltage starts to rise to when the RF signal in the RF switch is normally turned on. It is quantitatively defined as the time from when the control voltage of the switch rises from the set threshold (such as 50%) to when the voltage amplitude of the RF signal has risen to a higher threshold (such as 90%) of the maximum voltage.

[0008] 2. Off Time (or tOff): It measures the time interval from when the control voltage starts to drop to when the RF signal in the RF switch is cut off. It is quantitatively defined as the time from when the control voltage of the switch drops from the set threshold (such as 50%) to when the voltage amplitude of the RF signal has dropped to the lower threshold (such as 10%) of the minimum voltage.

[0009] 3. RF signal rising edge (R Frise Time or tRise): It measures the time interval from the beginning of the RF signal turning on to the basic turning on. The quantitative definition is the time interval from the RF signal voltage amplitude rising from the lower threshold of the maximum value (such as 10%) to the higher threshold of the maximum value (such as 90%).

[0010] 4. RF Fall Time (or tFall): This is the time interval from when the RF signal starts to turn off to when it is basically turned off. It is quantitatively defined as the time interval from when the RF signal voltage amplitude drops from a higher threshold value (such as 90%) of the maximum value to a lower threshold value (such as 10%) of the maximum value.

[0011] The visual definitions of the above four test items are as follows: Figure 1 shown.

[0012] The mainstream method for testing switching time in the industry is to use a real-time digital storage oscilloscope (RT-DSO) to collect signals and compare the voltage when the switch is powered on or off (i.e. ready to turn on or ready to turn off) with the amplitude of the RF signal output from the switch output port. Then, select the appropriate start and end points on the oscilloscope sampling data and calculate the switch on speed or off speed based on the start and end point information. Figure 2 As shown in the figure, manually mark the points on the oscilloscope sampling results, and calculate the RF time according to the time corresponding to the points. There are the following disadvantages:

[0013] 1. You need to manually select a suitable measurement time interval and a suitable oscilloscope sampling rate. If the two are not well matched, it may lead to loss of test value accuracy or measurement distortion;

[0014] 2. The start and end points need to be found manually, which has poor accuracy. Because each person may have different criteria for selecting the start and end points, the test results of different testers may differ. In addition, the probability of test errors will increase during manual testing;

[0015] 3. Low efficiency: If we test each one manually, it will be difficult to meet the growing production demand for RF switches.

[0016] 4. Large measurement fluctuations: As mentioned above, the oscilloscope needs to be used to collect RF signal data during the test, and the RF signal itself fluctuates, which will affect the selection of the start and end points, thereby causing distortion of the test value. In addition, each person has a different setting for the maximum RF signal voltage. Summary of the invention

[0017] The technical problem to be solved by the present invention is to design a high-precision and high-speed switching time test method, system and equipment for RF switches, provide automated testing capabilities, and cooperate with real-time oscilloscopes to realize automated switching time calculation for RF switches of the same model; realize stable switching time calculation and testing capabilities. The same device under test (DUT) can repeatedly produce expected stable test results, and the result fluctuation range can be controlled within a smaller range; realize high-precision measurement capabilities, and can realize nanosecond and picosecond measurement capabilities; realize high measurement speed measurement capabilities, which can far exceed the manual test speed for measurement, and the test speed is stable, so as to solve the existing technical problems.

[0018] In order to solve the above technical problems, the present invention provides a high-precision and high-speed switching time testing method of a radio frequency switch, comprising the following steps:

[0019] Step S1: Setting the test period T according to the characteristics of the device under test.

[0020] Step S2: The measured value V of the control voltage and the measured value S of the RF signal voltage passing through the switch at each sampling moment are collected by a real-time oscilloscope.

[0021] Step S3: performing envelope calculation on the collected radio frequency signal.

[0022] Step S4: According to the conduction characteristics of the RF switch, select data of a complete test cycle T from the collected data, obtain its starting point SegStart and end point SegStop, and the point before the starting point SegStart that satisfies the voltage value at a low level or a high level .

[0023] Step S5: Obtaining the maximum stable voltage center time of the RF signal , calculate the maximum stable voltage value of the RF signal .

[0024] Step S6: Acquire the key moments of the switching time, wherein the key moments include the key moments related to the radio frequency signal and the key moments related to the control voltage;

[0025] The key moments related to RF signals are:

[0026] After SegStart, the voltage value of the RF signal envelope first reaches The point is recorded as ;

[0027] After SegStart, the voltage value of the RF signal envelope first reaches The point is recorded as ;

[0028] from After that, the voltage value of the RF signal envelope first reaches The point is recorded as ;

[0029] from After that, the voltage value of the RF signal envelope first reaches The point is recorded as ;

[0030] in,

[0031] The RF signal actually reaches the high threshold of the maximum stable voltage. , It is the high threshold value of the maximum stable voltage of the RF signal;

[0032] The lower threshold value of the RF signal actually reaching the maximum stable voltage. , It is the lower threshold of the maximum stable voltage of the RF signal;

[0033] The key moments related to control voltage are:

[0034] from At the beginning, the control voltage changes to the set threshold, which is recorded as ;

[0035] from At the beginning, the control voltage changes to the set threshold, which is recorded as .

[0036] Specifically, for a radio frequency switch that is turned on by a rising control voltage, As the effective time of the rising edge of the control voltage, it is At the beginning, the voltage value found point by point is greater than or equal to point, As the effective time of the falling edge of the control voltage, At the beginning, the control voltage first drops to less than or equal to point.

[0037] Specifically, for a radio frequency switch that is turned on by a control voltage drop, As the effective time of the falling edge of the control voltage, Start by finding the voltage value that is less than or equal to point, As the effective time of the rising edge of the control voltage, it is Initially, the control voltage first rises to a value greater than or equal to point;

[0038] Step S7: Calculate the switching time, specifically:

[0039] On time tOn: ;

[0040] Cut-off time tOff: ;

[0041] RF signal rising edge tRise: ;

[0042] RF signal falling edge tFall: .

[0043] Furthermore, in step S2, the sampling time length of the real-time oscilloscope is at least 2T.

[0044] Furthermore, in step S3, the method for extracting the RF signal envelope is the Hilbert envelope method, the linear maximum envelope method, the sliding median envelope method, or the sliding maximum envelope method.

[0045] Furthermore, step S3 also includes smoothing the envelope to reduce the sharpness of the envelope curve, making the curve smoother, and avoiding the calculation of the switching time from being affected by the randomness of the unstable amplitude of the RF signal.

[0046] Furthermore, step S5 specifically includes the following steps:

[0047] Step S51: Define the maximum stable voltage center point of the RF signal according to SegStart and SegStop , which is the center point for calculating the maximum RF voltage value. , is the bias factor, .

[0048] Step S52: Setting the maximum calculation width of the RF voltage , .

[0049] Step S53: Make all The left and right radius is The average voltage value of the RF signal envelope is the maximum stable voltage of the RF signal, which is recorded as .

[0050] Further, in step S4, for the RF switch that is turned on by the control voltage rising, identifying and determining the complete test cycle T includes the following steps:

[0051] Step S41: Find the first voltage less than The moment is recorded as tempPoint;

[0052] Step S42: Starting from tempPoint and interval Find the first voltage greater than or equal to The point is recorded as SegStart;

[0053] Step S43: From the interval greater than SegStart Start looking for the point where the control voltage is less than The first point of , record this point as SegStop;

[0054] Step S44: among all the points before SegStart, determine and search for the point that satisfies the voltage value at the low level:

[0055] If we can find a level less than , it means that the currently found SegStart and SegStop must contain a complete test cycle T, and the found point is recorded as ; Among them, the parameter It needs to be set according to the fluctuation of the measured low level. Its value range is ;

[0056] If not found, it means that the currently found SegStart and SegStop cannot contain a complete test cycle T. Let SegStop be the new SegStart, and re-execute steps S43 to S44 until SegStart and SegStop that meet the requirements are found.

[0057] Further, in step S4, for the RF switch that is turned on by the control voltage drop, identifying and determining the complete test cycle T includes the following steps:

[0058] Step S41: Find the first voltage greater than The moment is recorded as tempPoint.

[0059] Step S42: Starting from tempPoint and interval Find the first data with a voltage less than or equal to The point is recorded as SegStart.

[0060] Step S43: From the interval greater than SegStart Start looking for the point where the control voltage is greater than The first point of is recorded as SegStop.

[0061] Step S44: among all the points before SegStart, determine and search for the points that satisfy the voltage value at the high level:

[0062] If we can find a level greater than , it means that the currently found SegStart and SegStop must contain a complete test cycle T, and the found point is recorded as ; Among them, the parameter It needs to be set according to the fluctuation of the measured high level, and its value range is ;

[0063] If not found, it means that the currently found SegStart and SegStop cannot contain a complete test cycle T. Let SegStop be the new SegStart, and re-execute steps S43 to S44 until SegStart and SegStop that meet the requirements are found.

[0064] Furthermore, , is the minimum stable interval ratio, .

[0065] The present invention also provides a high-precision and high-speed switching time test system for a radio frequency switch, comprising a parameter setting module, a data acquisition module, a data calculation module, a data processing module and a control module;

[0066] The parameter setting module is used to set required parameters, and the parameters include a test period T;

[0067] The data acquisition module is used to collect the time interval δ between two consecutive samplings of the oscilloscope, the measured value V of the control voltage at each sampling moment, and the measured value S of the RF signal voltage passing through the switch;

[0068] The data calculation module includes an envelope calculation unit, a maximum stable voltage calculation unit and a switching time calculation unit, wherein the envelope calculation unit is used to calculate the envelope of the collected RF signal, the maximum stable voltage calculation unit is used to calculate the maximum stable voltage value of the RF signal, and the switching time calculation unit is used to calculate the on-time, the off-time, the rising edge of the RF signal and the falling edge of the RF signal;

[0069] The data processing module is used to filter out data of a complete test cycle from the signal data captured by the real-time oscilloscope, obtain its starting point and end point; and obtain the key moment of the switching time;

[0070] The control module controls other modules to perform related operations according to the aforementioned high-precision and high-speed RF switch switching time testing method.

[0071] Furthermore, a smoothing module is included, which is used to smooth the envelope to reduce the sharpness of the envelope curve and make the curve smoother. Smoothing is suitable for situations where the signal itself has poor stability or the oscilloscope sampling jitter is large.

[0072] Furthermore, since poor cable performance may cause voltage overshoot, high-frequency oscillation and the like, the smoothing module is also used to control the smoothing processing of the voltage signal. The use of smoothing can filter out the above-mentioned situations to a certain extent.

[0073] The present invention also provides a high-precision and high-speed switching time testing device for a radio frequency switch, comprising:

[0074] at least one processor; and

[0075] at least one memory in communication with the processor;

[0076] The memory stores instructions that can be executed by the processor, and the instructions are executed by the processor to enable the device to perform the aforementioned high-precision and high-speed switching time test method of the radio frequency switch.

[0077] Beneficial effects of the present invention:

[0078] 1. The test method of the present invention provides several adjustable parameters, through which a variety of RF switch products can be flexibly adapted. Since the control voltage threshold and the RF signal voltage threshold for time determination can be changed, products with different calculation standards can be adapted.

[0079] 2. Due to the highly automated process, the same model of product can be tested automatically without human intervention. Compared with manual analysis, the test speed can be increased by more than 5 times (single execution time is less than 1s), thereby improving production and testing efficiency. For the same model of product, only a set of parameters need to be provided to achieve automatic calculation.

[0080] 3. For different products, the present invention still maintains the same calculation logic. There will be no subjectivity in testing products of different models and specifications.

[0081] 4. The calculation accuracy of the present invention is improved as the measurement accuracy of the oscilloscope is improved, so it can have the same accuracy as the matching oscilloscope and also has compatibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] The specific implementation of the present invention will be further explained below in conjunction with the accompanying drawings.

[0083] Figure 1 It is a visual definition diagram of the RF switch test item (rising conduction);

[0084] Figure 2 A schematic diagram of manually marking points on the oscilloscope sampling results in the existing test method;

[0085] Figure 3 A flowchart of a method for testing the switching time of a high-precision and high-speed radio frequency switch of the present invention;

[0086] Figure 4 It is a thumbnail of the RF signal sampled by the oscilloscope;

[0087] Figure 5 is the amplified RF signal diagram;

[0088] Figure 6 This is the envelope effect diagram of the radio frequency signal after Hilbert transform;

[0089] Figure 7 A distribution diagram of all maximum value points for RF signals;

[0090] Figure 8 It is the data graph of linear maximum envelope and RF signal;

[0091] Fig. 9 This is a flow chart of the method for identifying and determining a complete test cycle in Example 1;

[0092] Fig.10 It is a visual definition diagram of the RF switch test item (falling conduction);

[0093] Fig.11 This is a flow chart of the method for identifying and determining a complete test cycle in Example 2;

[0094] Fig.12 The system block diagram of the switching time test system of the high-precision and high-speed radio frequency switch of the present invention. DETAILED DESCRIPTION

[0095] Example 1

[0096] Combination Figure 3 The high-precision and high-speed switching time testing method of the radio frequency switch of this embodiment comprises the following steps:

[0097] Step S1: Set the test cycle T according to the characteristics of the device under test. It is required that within a test cycle, the switch will be stably turned on once and stably turned off once. An example of a test cycle is shown in the figure below: Figure 1 shown.

[0098] Step S2: The measured value V of the control voltage and the measured value S of the RF signal voltage passing through the switch at each sampling moment are collected by a real-time oscilloscope.

[0099] In this embodiment, preferably, in step S2, the sampling time of the real-time oscilloscope is at least 2T, ensuring that the real-time oscilloscope can obtain the voltage and RF signal data of a complete test cycle at any time when it starts measuring. Since the on and off of the RF switch is controlled by the high and low control voltage (here we only discuss the case of high-level conduction, taking 3.3V as an example of high level, and the low level is 0V), when the control circuit outputs a control voltage with a period of T, at the beginning of the T period, the RF switch receives a high level, and before the end of the T period, the RF switch receives a low level, and conduction and cutoff control are performed. Since the measurement width of the real-time oscilloscope is at least 2T, the real-time oscilloscope can obtain the voltage and RF signal data of a complete test cycle at any time when it starts measuring.

[0100] Specifically, the slower switching time is also basically in us, so the test period T can often be set to 0.1ms~10ms, such as 10ms or 100us. However, when setting, it is also necessary to see whether the generated voltage change switching generation time can be met. If the response time can be met, the test period can be shortened as much as possible to reduce the data collected by the oscilloscope, so as to reduce the pressure of subsequent calculations of the present invention.

[0101] Specifically, the time interval between two consecutive samples of the real-time oscilloscope is δ. According to different sampling rates, the real-time oscilloscope will obtain measurement data of different lengths. If the total number of samples of a single oscilloscope is N, a time series of oscilloscope samples can be generated. The time array of the N samples of the oscilloscope is: , let the control voltage sampling array be V, and the RF signal sampling array be S, then the oscilloscope sampling result can be simply recorded as: ,refer to Figure 1 As shown, for Figure 1 The horizontal coordinate in is Figure 1 The yellow curve in the figure is Figure 1 The green curve. Figure 1 The RF signal in the figure is a sine wave with different amplitudes as the switch is turned on and off, but with the same period. When viewed on a wider coordinate scale, the sampling results will be stacked together to form the green "area" in the figure, but in fact it is composed of continuous points. After zooming in on the coordinate scale, you can see the curve shape of the sine wave.

[0102] Step S3: Calculate the envelope of the collected RF signal. Figure 2 As shown in the figure, when the switch is turned on, the sampling value of the RF signal will gradually increase from small to stable, but the RF signal is a periodic sine wave. Figure 2The RF signal (green part) in the image appears to have a uniform amplitude, but in fact, due to the sampling jitter of the oscilloscope itself and the jitter of the signal source itself, the amplitude of the RF signal is always oscillating. Figure 4 Figure 1 shows a thumbnail of the RF signal sampled by the oscilloscope, and Figure 5 shows the enlarged RF signal. If the original data is used for calculation directly, the wrong moment will be found. Therefore, the envelope of the RF signal needs to be calculated. The envelope can be simply defined as the upper edge line of the RF signal amplitude (i.e. the maximum value of each oscillation cycle). After that, all calculations involving the RF signal are calculated using the voltage value of the envelope to obtain more stable and reliable measurement results.

[0103] In this embodiment, preferably, in step S3, the method for extracting the envelope of the radio frequency signal is a Hilbert envelope method, a linear maximum envelope method, a sliding median envelope method, or a sliding maximum envelope method.

[0104] Specifically, the Hilbert envelope method performs Hilbert transform on the sampled data of the RF signal and takes the absolute value of the result. The formula is:

[0105] ;

[0106] in, The RF signal data obtained by filter sampling will be complex data after Hilbert transform. The Hilbert envelope of the RF signal can be obtained by taking the membrane length of the complex data. , the effect diagram is as follows Figure 6 The horizontal axis is , the green curve is the RF signal and the black curve is the Hilbert envelope.

[0107] Specifically, a linear maximum envelope may also be used, and the specific method is as follows:

[0108] Find all the maximum points of the RF signal. The RF signal data is recorded as , for any three consecutive points , , , if satisfied and ,but is a local maximum.

[0109] According to the above definition, find all local maximum sets of S , whose distribution on the RF signal is as follows Figure 7 shown. Figure 7Each inverted triangle in represents a local maximum. It can be seen that the number of local maxima is far less than the number of signal data, so it is necessary to perform linear interpolation on the local maxima to obtain a linear maximum envelope so that the number of its values ​​is equal to S, so that the envelope covering the entire signal upper bound can be extracted.

[0110] For any value s in S, if it does not belong to , then in Find the largest local maximum value smaller than s (denoted as ) and the smallest local maximum value greater than s (denoted as ), find in T ,s, The corresponding components in array T are recorded as ,t, ,make

[0111] ;

[0112] is the element corresponding to t in the linear maximum array. Using this formula, fill the number of elements in the local maximum array to be equal to S, and you get the linear maximum envelope, recorded as . Figure 8 This is the data diagram of the linear maximum envelope and RF signal, and the horizontal axis is The vertical coordinates are S and ,The green curve in the figure is the RF signal, and the black curve is the linear maximum envelope.

[0113] In specific use, the envelope method can be selected according to the actual signal. The linear maximum envelope restores the signal voltage better, but has weak interference resistance. The voltage restoration ability of the Hilbert envelope is relatively weak, but it has strong anti-interference ability. In actual use, if a more stable and less susceptible to interference measurement result is required, or the signal source / crystal amplitude stability is poor, the Hilbert envelope can be used. Conversely, if the amplitude stability of the signal source is high and the result is desired to be as accurate as possible, the linear maximum envelope can be used. However, it should be noted that the accuracy difference between the two is generally not greater than 1% of the measurement result.

[0114] In addition to the Hilbert envelope method or the linear maximum envelope method, the sliding median envelope method or the sliding maximum envelope method can also be used. The sliding median envelope uses a fixed-length window to slide on the signal at a speed of one point. Each time it slides, the middle value of the signal value in the window is selected as the envelope value to generate an envelope signal. The sliding maximum envelope is similar to the sliding median. A fixed-length window is used to slide on the signal at a speed of one point. Each time it slides, the maximum value of the signal value in the window is selected as the envelope value to generate the envelope. The sliding median is characterized by high stability, but it will directly change the amplitude of the envelope relative to the signal, which may affect the calculation results. The sliding maximum has strong anti-interference ability in the signal range with stable amplitude, but if the signal in the window has a large amplitude difference, a certain degree of signal amplitude restoration distortion may occur.

[0115] Preferably, in this embodiment, step S3 further includes smoothing the envelope to reduce the sharpness of the envelope curve, making the curve smoother, and preventing the calculation of the switching time from being affected by the randomness of the unstable amplitude of the RF signal.

[0116] Specifically, it can be seen from the linear maximum envelope that the envelope edge of the linear maximum is relatively sharp and too close to the signal, which loses some versatility. Therefore, it is considered to add smoothing to reduce the sharpness of the envelope curve and make the curve smoother. The significance of envelope smoothing is to avoid the calculation of the switching time being affected by the randomness of the unstable amplitude of the RF signal.

[0117] Specifically, the envelope smoothing can be performed by sliding average. For the i-th point of the envelope curve , set a fixed length n, if n is an odd number, use to replace the original value; if n is an even number, use To replace the original value, thus forming a smoothed envelope curve. For those points on the left and right sides that do not meet so many points, only the available points are used to calculate the smoothed envelope points. Envelope smoothing is not a necessary step. If the stability of the signal itself is poor or the jitter of the oscilloscope sampling is large, envelope smoothing can be performed. The value range of n is generally around 10 to 30. In this embodiment, n is 21. If n is too small, it will not play a smoothing role. If n is too large, the smoothed result will lose the original curve characteristics.

[0118] Envelope smoothing also supports sliding median smoothing, which is implemented in the same way as sliding median envelope. A window of fixed length is used to slide on the envelope. The sliding speed is a value, and the middle value in the window is used as the new envelope point each time it slides.

[0119] Preferably, in this embodiment, the voltage signal V may also be smoothed. Since poor cable performance may cause voltage overshoot, high-frequency oscillation, and the like, smoothing may filter out the above-mentioned situations to a certain extent.

[0120] Step S4: According to the conduction characteristics of the RF switch, select data of a complete test cycle T from the collected data, obtain its starting point SegStart and end point SegStop, and the point before the starting point SegStart that satisfies the voltage value at a low level or a high level .

[0121] In this embodiment, a radio frequency switch that is turned on by controlling voltage rise is taken as an example. Fig. 9 As shown, the identification and determination of the complete test cycle T in step S4 includes the following steps:

[0122] Get the time coordinates of all sampling points of the voltage signal, and store the voltage values ​​in the voltage signal greater than or equal to The sampling points are recorded as 1, otherwise they are recorded as 0, forming a decision array C, where is the maximum control voltage, To control the voltage rising and falling edges, the effective threshold is usually 50%.

[0123] Step S41: Find the first 0 from the decision array C, that is, the first voltage is less than The moment is recorded as tempPoint.

[0124] Step S42: Starting from tempPoint and interval Find the first voltage greater than or equal to , and record this point as SegStart.

[0125] Step S43: From the interval with SegStart greater than Start looking for the point where the control voltage is less than The first point of is called SegStop.

[0126] In this embodiment, preferably, in order to filter out the oscillation of the control voltage, a minimum stable interval ratio is set. , , In this embodiment Set to 0.1%.

[0127] Step S44: among all the points before SegStart, determine and search for the point that satisfies the voltage value at the low level:

[0128] If we can find a level less than , it means that the currently found SegStart and SegStop must contain a complete test cycle T, and the found point is recorded as ; Among them, the parameters It needs to be set according to the fluctuation of the measured low level. Its value range is In this embodiment, Set to 0.01;

[0129] If not found, it means that the currently found SegStart and SegStop cannot contain a complete test cycle T. Let SegStop be the new SegStart, and re-execute steps S43 to S44 until SegStart and SegStop that meet the requirements are found.

[0130] Step S5: Obtaining the maximum stable voltage center time of the RF signal , calculate the maximum stable voltage value of the RF signal based on SegStart and SegStop . Combined Figure 2 As shown in the figure, when the RF switch is turned on and off, the rate at which the RF signal voltage increases from a small value and decreases from a large value is different, which is related to the physical properties of the switch itself. Because of this, the present invention designs a bias factor .

[0131] In this embodiment, step S5 preferably includes the following steps:

[0132] Step S51: Define the maximum stable voltage center point of the RF signal according to SegStart and SegStop , which is the center point for calculating the maximum RF voltage value. , is the bias factor, In this embodiment, Take 0.75, if the switch opening and closing speeds are basically the same, then It can be taken as 0.5.

[0133] Step S52: Setting the maximum calculation width of the RF voltage , In this embodiment, Set to 0.005.

[0134] Step S53: Make all The left and right radius is The average voltage value of the RF signal envelope is the maximum stable voltage of the RF signal, which is recorded as .

[0135] Step S6: Acquire the key moments of the switching time, wherein the key moments include the key moments related to the radio frequency signal and the key moments related to the control voltage;

[0136] The key moments related to RF signals are:

[0137] After SegStart, the voltage value of the RF signal envelope first reaches The point is recorded as ;

[0138] After SegStart, the voltage value of the RF signal envelope first reaches The point is recorded as ;

[0139] from After that, the voltage value of the RF signal envelope first reaches The point is recorded as ;

[0140] from After that, the voltage value of the RF signal envelope first reaches The point is recorded as ;

[0141] in,

[0142] The RF signal actually reaches the high threshold of the maximum stable voltage. , It is the high threshold of the maximum stable voltage of the RF signal, usually 90% or 80%, and needs to be set according to the switch standard.

[0143] The lower threshold value of the RF signal actually reaching the maximum stable voltage. , This is the lower threshold of the maximum stable voltage of the RF signal; usually 10% or 20% and needs to be set according to the switch standard.

[0144] The key moments related to control voltage are:

[0145] from At the beginning, the control voltage changes to the set threshold, which is recorded as ;

[0146] from At the beginning, the control voltage changes to the set threshold, which is recorded as ;

[0147] Specifically, for the RF switch that is turned on when the control voltage rises in this embodiment, As the effective time of the rising edge of the control voltage, it is At the beginning, find the voltage value that is greater than or equal to point, As the effective time of the falling edge of the control voltage, it is At the beginning, the control voltage first drops to less than or equal to point.

[0148] Step S7: Calculate the switching time, specifically:

[0149] On time tOn: ;

[0150] Cut-off time tOff: ;

[0151] RF signal rising edge tRise: ;

[0152] RF signal falling edge tFall: .

[0153] Thus, the on time tOn, the off time tOff, the rising edge tRise of the RF switch, and the falling edge tFall of the RF signal can be calculated.

[0154] Example 2

[0155] The switching time test method of the high-precision and high-speed RF switch of this embodiment is different from the method in Example 1 in that the test method in Example 1 takes the RF switch with the control voltage rising as an example, while the method in this application is used for testing the RF switch with the control voltage falling. The control voltage, RF signal and test parameters of the falling conduction are defined as follows: Fig.10 Compared with the technical solution in Example 1, except for the following steps, the remaining steps are the same and will not be repeated here.

[0156] Step S4 in this embodiment is different from that in Embodiment 1, such as Fig.11 As shown, step S4 in this embodiment specifically includes the following steps to identify and determine the complete test cycle T of the RF switch that controls the voltage to drop and turn on:

[0157] Get the time coordinates of all sampling points of the voltage signal, and set the voltage value in the voltage signal to be less than or equal to The sampling points are recorded as 1, otherwise they are recorded as 0, forming a decision array C, where is the maximum control voltage, To control the voltage rising and falling edges, the effective threshold is usually 50%.

[0158] Step S41: Find the first 0 from the decision array C, that is, find the first voltage greater than The moment is recorded as tempPoint.

[0159] Step S42: Starting from tempPoint and interval Find the first data with a voltage less than or equal to The point is recorded as SegStart.

[0160] Step S43: From the interval greater than SegStart Start looking for the point where the control voltage is greater than The first point of is recorded as SegStop.

[0161] In this embodiment, preferably, in order to filter out the oscillation of the control voltage, a minimum stable interval ratio is set. , , In this embodiment Set to 0.1%.

[0162] Step S44: among all the points before SegStart, determine and search for the points that satisfy the voltage value at the high level:

[0163] If we can find a level greater than , it means that the currently found SegStart and SegStop must contain a complete test cycle T, and the found point is recorded as ; Among them, the parameter It needs to be set according to the fluctuation of the measured high level, and its value range is In this embodiment, Set to 0.95;

[0164] If not found, it means that the currently found SegStart and SegStop cannot contain a complete test cycle T. Let SegStop be the new SegStart, and re-execute steps S43 to S44 until SegStart and SegStop that meet the requirements are found.

[0165] In addition, in the key moment of obtaining the switching time in step S6 of this embodiment, the key moment of obtaining the RF signal is the same as that in Embodiment 1, but the key moment of obtaining the control voltage is different, specifically:

[0166] The key moments related to obtaining the control voltage are:

[0167] from At the beginning, the control voltage changes to the set threshold, which is recorded as ;

[0168] from At the beginning, the control voltage changes to the set threshold, which is recorded as ;

[0169] Specifically, in this embodiment, for the RF switch that is turned on by controlling the voltage drop, As the effective time of the falling edge of the control voltage, Start by finding the voltage value that is less than or equal to point, As the effective time of the rising edge of the control voltage, it is Initially, the control voltage first rises to a value greater than or equal to point.

[0170] The remaining technical features in this embodiment are the same as those in Embodiment 1, thereby the on-time tOn, the off-time tOff, the rising edge tRise of the RF signal and the falling edge tFall of the RF switch can be calculated, and the calculation method is the same as that in Embodiment 1.

[0171] Example 3

[0172] Combination Fig.12 The high-precision and high-speed switching time test system of the radio frequency switch of the embodiment of the present invention includes a parameter setting module, a data acquisition module, a data calculation module, a data processing module and a control module:

[0173] The parameter setting module is used to set required parameters, and the parameters include a test period T.

[0174] The data acquisition module is used to collect the time interval δ between two consecutive samplings of the oscilloscope, the measured value V of the control voltage at each sampling moment, and the measured value S of the RF signal voltage passing through the switch.

[0175] The data calculation module includes an envelope calculation unit, a maximum stable voltage calculation unit and a switching time calculation unit. The envelope calculation unit is used to calculate the envelope of the collected RF signal, the maximum stable voltage calculation unit is used to calculate the maximum stable voltage value of the RF signal, and the switching time calculation unit is used to calculate the on-time, the off-time, the rising edge of the RF signal and the falling edge of the RF signal.

[0176] The data processing module is used to filter out data of a complete test cycle from the signal data captured by the real-time oscilloscope, obtain its starting point and end point; and obtain the key moment of the switching time.

[0177] The control module controls other modules to perform relevant operations according to the switching time testing method of a high-precision and high-speed radio frequency switch described in any one of Embodiment 1 or Embodiment 2.

[0178] Preferably, this embodiment further includes a smoothing module, which is used to smooth the envelope to reduce the sharpness of the envelope curve and make the curve smoother. Smoothing is suitable for situations where the signal itself has poor stability or the oscilloscope sampling jitter is large.

[0179] In this embodiment, since poor cable performance may cause voltage overshoot, high-frequency oscillation and other phenomena, the smoothing module is also used to control the smoothing processing of the voltage signal. The use of smoothing can filter out the above-mentioned situations to a certain extent.

[0180] Example 4

[0181] This embodiment provides a high-precision and high-speed switching time test device for a radio frequency switch, comprising:

[0182] at least one processor; and

[0183] at least one memory in communication with the processor;

[0184] The memory stores instructions that can be executed by the processor, and the instructions are executed by the processor to enable the device to perform the switching time test method of the high-precision and high-speed radio frequency switch described in any one of Example 1 or Example 2.

[0185] Since the RF industry uses a "switch" to control the opening and closing of the RF signal of a certain device, and the opening and closing is often controlled by the high and low voltage, the present invention is suitable for measuring the opening and closing speed of all devices that control the opening and closing of RF signals with high and low levels, including but not limited to the signal opening and closing time measurement of RF signal sources and RF amplifiers.

[0186] Many specific details are described in the above description to facilitate a full understanding of the present invention. However, the above description is only a preferred embodiment of the present invention. The present invention can be implemented in many other ways different from those described herein, so the present invention is not limited to the specific implementation disclosed above. At the same time, any person familiar with the art can make many possible changes and modifications to the technical solution of the present invention using the methods and technical contents disclosed above without departing from the scope of the technical solution of the present invention, or modify it into an equivalent embodiment of equivalent changes. Any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the scope of protection of the technical solution of the present invention.

Claims

1. A high-precision and high-speed switching time test method for a radio frequency switch, characterized in that: The steps include: Step S1: setting the test period T according to the characteristics of the device under test; Step S2: collecting the measured value V of the control voltage and the measured value S of the RF signal voltage passing through the switch at each sampling moment through a real-time oscilloscope; Step S3: performing envelope calculation on the collected radio frequency signal; Step S4: According to the conduction characteristics of the RF switch, select data of a complete test cycle T from the collected data, obtain its starting point SegStart and end point SegStop, and the point before the starting point SegStart that satisfies the voltage value at a low level or a high level ; Step S5: Obtaining the maximum stable voltage center time of the RF signal , calculate the maximum stable voltage value of the RF signal ; Step S6: Acquire the key moments of the switching time, wherein the key moments include the key moments related to the radio frequency signal and the key moments related to the control voltage; The key moments related to RF signals are: After SegStart, the voltage value of the RF signal envelope first actually reaches the lower threshold of the maximum stable voltage. The point is recorded as , and the voltage value of the RF signal envelope first actually reaches the high threshold of the maximum stable voltage The point is recorded as ; from After that, the voltage value of the RF signal envelope first actually reaches the high threshold of the maximum stable voltage. The point is recorded as , and the voltage value of the RF signal envelope first actually reaches the lower threshold of the maximum stable voltage The point is recorded as ; The key moments related to control voltage are: from At the beginning, the control voltage changes to the set threshold, which is recorded as ; from At the beginning, the control voltage changes to the set threshold, which is recorded as ; Step S7: Calculate the switching time, specifically: On time tOn: ; Cut-off time tOff: ; RF signal rising edge tRise: ; RF signal falling edge tFall: ; In step S4, for the RF switch that is turned on by the control voltage rising, identifying and determining the complete test cycle T includes the following steps: Step S41: Find the first voltage less than The moment is recorded as tempPoint; Step S42: Starting from tempPoint and interval Find the first voltage greater than or equal to The point is recorded as SegStart; Step S43: From the interval greater than SegStart Start looking for the point where the control voltage is less than The first point of , record this point as SegStop; Step S44: among all the points before SegStart, determine and search for the point that satisfies the voltage value at the low level: If it can be found, it means that the currently found SegStart and SegStop must contain a complete test cycle T, and the found point is recorded as ; If not found, it means that the currently found SegStart and SegStop cannot contain a complete test cycle T, let SegStop be the new SegStart, and re-execute steps S43 to S44 until SegStart and SegStop that meet the requirements are found; In step S4, for the RF switch that is turned on by the control voltage drop, identifying and determining the complete test cycle T includes the following steps: Step S41: Find the first voltage greater than The moment is recorded as tempPoint; Step S42: Starting from tempPoint and interval Find the first data with a voltage less than or equal to The point is recorded as SegStart; Step S43: From the interval with SegStart greater than Start looking for the point where the control voltage is greater than The first point of , record this point as SegStop; Step S44: among all the points before SegStart, determine and search for the points that satisfy the voltage value at the high level: If it can be found, it means that the currently found SegStart and SegStop must contain a complete test cycle T, and the found point is recorded as ; If not found, it means that the currently found SegStart and SegStop cannot contain a complete test cycle T, let SegStop be the new SegStart, and re-execute steps S43 to S44 until SegStart and SegStop that meet the requirements are found; is the maximum control voltage, Identify effective thresholds for opening and closing the rising and falling edges of the control voltage; Step S5 specifically includes the following steps: Step S51: Define the maximum stable voltage center point of the RF signal according to SegStart and SegStop , which is the center point for calculating the maximum RF voltage value. , is the bias factor, ; Step S52: Setting the maximum calculation width of the RF voltage , ; Step S53: Make all The left and right radius is The average voltage value of the RF signal envelope is the maximum stable voltage of the RF signal, which is recorded as .

2. The switching time test method of a high-precision and high-speed radio frequency switch according to claim 1 is characterized in that: In step S2, the sampling time length of the real-time oscilloscope is at least 2T.

3. The switching time test method of a high-precision and high-speed radio frequency switch according to claim 1, characterized in that: In step S3, the method for extracting the envelope of the radio frequency signal is the Hilbert envelope method, the linear maximum envelope method, the sliding median envelope method, or the sliding maximum envelope method.

4. The switching time test method of a high-precision and high-speed radio frequency switch according to claim 1 is characterized in that: Step S3 also includes smoothing the envelope to reduce the sharpness of the envelope curve, making the curve smoother, and preventing the calculation of the switching time from being affected by the randomness of the unstable amplitude of the RF signal.

5. The switching time test method of a high-precision and high-speed radio frequency switch according to claim 1, characterized in that: , is the minimum stable interval ratio, .

6. A switching time test system for a radio frequency switch, characterized in that: It includes parameter setting module, data acquisition module, data calculation module, data processing module and control module; The parameter setting module is used to set required parameters, and the parameters include a test period T; The data acquisition module is used to collect the time interval δ between two consecutive samplings of the oscilloscope, the measured value V of the control voltage at each sampling moment, and the measured value S of the RF signal voltage passing through the switch; The data calculation module includes an envelope calculation unit, a maximum stable voltage calculation unit and a switching time calculation unit, wherein the envelope calculation unit is used to calculate the envelope of the collected RF signal, the maximum stable voltage calculation unit is used to calculate the maximum stable voltage value of the RF signal, and the switching time calculation unit is used to calculate the on-time, the off-time, the rising edge of the RF signal and the falling edge of the RF signal; The data processing module is used to filter out data of a complete test cycle from the signal data captured by the real-time oscilloscope, obtain its starting point and end point; and obtain the key moment of the switching time; The control module controls other modules to perform relevant operations according to the switching time testing method of a high-precision and high-speed radio frequency switch according to any one of claims 1-5.

7. A switching time test device for a radio frequency switch, characterized in that: include: at least one processor; as well as at least one memory in communication with the processor; The memory stores instructions executable by the processor, and the instructions are executed by the processor to enable the device to execute the switching time test method of a high-precision and high-speed radio frequency switch according to any one of claims 1 to 5.

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