A method and device for obtaining transmission delay of a trigger signal based on a DSP

Abstract

The application discloses a transmission delay acquisition method and device of a DSP-based trigger signal. The transmission delay acquisition method of the DSP-based trigger signal comprises the following steps: acquiring trigger output delay information of a transmitting radio frequency drive variable frequency circuit, trigger input delay information, transmission delay information between a DSP and a DAC, time required for the DAC to receive data and generate a waveform, and transmitting radio frequency channel group delay information; acquiring equipment requirement information; and acquiring a delay time of a Trigger Out signal output by the DSP according to the equipment requirement information and the trigger output delay information, the trigger input delay information, the transmission delay information between the DSP and the DAC, the time required for the DAC to receive data and generate the waveform, and the transmitting radio frequency channel group delay information. The transmission delay acquisition method of the DSP-based trigger signal provided by the application is an automatic calculation and configuration method of a delay time, is added to a DSP, realizes self-configuration of the delay time based on a configuration mode, and can report the delay time, thereby facilitating cascade use in a complex system.

Description

Technical Field

[0001] The present application relates to the technical field of signal delay calculation, and in particular to a method for obtaining the transmission delay of a trigger signal based on a DSP and a device for obtaining the transmission delay of a trigger signal based on a DSP. Background Art

[0002] With the development of modern communications and the increasing demand for spectrum utilization, digital modulation signals have been widely developed and applied. Compared to analog modulation, digital modulation offers superior anti-interference capabilities and security. Through modulation and demodulation, more information can be transmitted within limited channel resources, and signal processing technologies such as coding and encryption have been developed.

[0003] In the RF signal transmission and reception test, the input and output trigger of the Trigger signal can usually be used to achieve test synchronization to analyze the channel capability of the device. Figure 1 As described above, in the common digital signal processing flow of the Trigger test, when entering the Trigger trigger mode, the main control unit sends instructions to the DSP. Only when the DSP receives the Trigger In signal can it trigger the execution of all instructions and output Trigger Out to the outside according to the established configuration of the internal DSP.

[0004] If the actual test process is based directly on the Trigger signal, the transmission delay from the DSP receiving the Trigger signal to the DAC data signal cannot be determined. In addition, the Trigger signal input by the device itself through the PCIe interface or external interface will also have a transmission delay in the process of being transmitted to the DSP unit. In this case, there is always a delay time between the RF signal and the Trigger signal.

[0005] Low-frequency, low-speed applications are less sensitive to this delay. However, with the increasing use of digital modulation signals, testing of digital signal modulation and demodulation has placed higher demands on synchronization. How can we determine the propagation delay of the trigger signal to ensure signal synchronization? Excessive delay prevents the Trigger Out signal from aligning with the output waveform, resulting in a lack of proper status indication and increasing the difficulty of testing downstream equipment in the system. Furthermore, waveforms of different formats vary in their characteristic parameters (such as waveform size and sampling rate), resulting in varying propagation delays. Testing the propagation delay of each waveform individually would complicate the process and increase workload. Furthermore, in more complex systems with multiple cascaded devices, the cumulative delays can have a significant impact. Summary of the Invention

[0006] The object of the present invention is to provide a DSP-based method for acquiring the transmission delay of a Trigger signal to at least solve one of the above technical problems.

[0007] In one aspect of the present invention, a method for obtaining the transmission delay of a trigger signal based on a DSP is provided. The method for obtaining the transmission delay of a trigger signal based on a DSP comprises:

[0008] Obtain the trigger output delay information of the transmitting RF drive frequency conversion circuit, the trigger input delay information, the transmission delay information between the DSP and DAC, the time required for the DAC to receive data and generate a waveform, and the transmitting RF channel group delay information;

[0009] Obtain equipment demand information;

[0010] The DSP's external output Trigger Out signal delay time is obtained based on the device requirement information, trigger output delay information, trigger input delay information, transmission delay information between the DSP and DAC, the time required for the DAC to receive data and generate a waveform, and the transmit RF channel group delay information.

[0011] Optionally, the device requirement information includes external Trigger In input control information and external Trigger In input control information;

[0012] When the device requirement information indicates that no external Trigger In input control information is required, the delay time of the DSP outputting the Trigger Out signal externally is obtained based on the device requirement information and the trigger output delay information, the trigger input delay information, the transmission delay information between the DSP and the DAC, the time required for the DAC to receive data and generate a waveform, and the transmit RF channel group delay information by using the following formula:

[0013] Ta=T5+T4+T3-T1; where

[0014] Ta is the delay time for the DSP to output the Trigger Out signal when the device requirement information is that no external Trigger In input control information is required; T5 is the delay information of the transmitting RF channel group; T4 is the time required for the DAC to receive data and generate a waveform; T3 is the transmission delay information between the DSP and DAC; T1 is the trigger output delay information.

[0015] Optionally, when the device requirement information requires external Trigger In input control information, the delay time of the DSP outputting the Trigger Out signal externally is obtained based on the device requirement information and the trigger output delay information, the trigger input delay information, the transmission delay information between the DSP and the DAC, the time required for the DAC to receive data and generate a waveform, and the transmit RF channel group delay information by using the following formula:

[0016] Tb=T5+T4+T3-T1+T2; where

[0017] Tb is the delay time for the DSP to output the Trigger Out signal when the device requires external Trigger In input control information; T5 is the delay information of the transmitting RF channel group; T4 is the time required for the DAC to receive data and generate a waveform; T3 is the transmission delay information between the DSP and DAC; T1 is the trigger output delay information; T2 is the trigger input delay information.

[0018] Optionally, the trigger output delay information is obtained by the following formula:

[0019] T1=l 表层线 *v 表层线 +l 内层线 *v 内层线 +t 过孔 ; Among them, l 表层线 Represents the length of the Trigger signal passing through the surface line, v 表层线 represents the propagation speed of the surface line; l 内层线 Represents the length of the inner line through which the Trigger signal passes, v 内层线 represents the propagation speed of the inner line; t 过孔 Represents the sum of all times traveling through the via.

[0020] Optionally, the transmit RF channel group delay information is obtained by the following formula:

[0021] Tinter=Tag_0+(freq_inter-freq_a)*[(Tag_b-Tag_a) / freq_b-freq_a)]; where,

[0022] Tinter is the transmitting RF channel group delay information, freq_inter is the required frequency point, freq_a is the frequency of the previous calibration frequency point of the required frequency point, freq_b is the frequency of the next frequency point of the required frequency point, Tag_a and Tag_b are the frequencies of the previous calibration frequency point and the next frequency point of the frequency point, respectively.

[0023] Optionally, the DSP-based method for acquiring the transmission delay of the Trigger signal further includes:

[0024] Obtain the receiving RF channel group delay information of the receiving RF driving frequency conversion circuit, the delay information of the ADC discretizing the input signal and routing the data output, the receiving transmission delay between the DSP and ADC, the receiving trigger output delay information, and the receiving trigger input delay information;

[0025] The delay time of the spectrum analyzer device is obtained based on the device requirement information, the receiving RF channel group delay information of the receiving RF driving frequency conversion circuit, the delay information of the ADC discretizing the input signal and routing the data output, the receiving transmission delay between the DSP and ADC, the receiving trigger output delay information, and the receiving trigger input delay information.

[0026] Optionally, when the device requirement information indicates that no external Trigger In input control information is required, the delay time for the spectrum analyzer device is obtained based on the device requirement information and the receiving RF channel group delay information of the receiving RF driving frequency conversion circuit, the delay information of the ADC discretizing the input signal and routing the data output, the receiving transmission delay between the DSP and the ADC, the receiving trigger output delay information, and the receiving trigger input delay information by using the following formula:

[0027] Tc=T15+T14+T13-T11; among them,

[0028] Tc is the delay time for the spectrum analyzer device when the device requirement information is that no external Trigger In input control information is required, T15 is the receiving trigger input delay information, T14 is the receiving trigger output delay information, T13 is the receiving transmission delay between DSP and ADC, and T11 is the receiving RF channel group delay information.

[0029] Optionally, when the device requirement information requires external Trigger In input control information, the delay time of the spectrum analyzer device is obtained based on the device requirement information and the receiving RF channel group delay information of the receiving RF driving frequency conversion circuit, the delay information of the ADC discretizing the input signal and routing the data output, the receiving transmission delay between the DSP and the ADC, the receiving trigger output delay information, and the receiving trigger input delay information by using the following formula:

[0030] Td=T15+T14+T13-T11+T12; among them,

[0031] Td is the delay time for the spectrum analyzer device when the device requirement information is that external Trigger In input control information is required, T15 is the delay information for receiving trigger input, T14 is the delay information for receiving trigger output, T13 is the receive transmission delay between DSP and ADC, T11 is the delay information for receiving RF channel group, and T12 is the delay information for ADC to discretize the input signal and route the data out.

[0032] The present application also provides a device for obtaining a transmission delay of a trigger signal based on a DSP, characterized in that the device for obtaining a transmission delay of a trigger signal based on a DSP comprises:

[0033] An acquisition module is used to obtain trigger output delay information of the transmitting RF driving frequency conversion circuit, trigger input delay information, transmission delay information between the DSP and DAC, time required for the DAC to receive data and generate a waveform, and transmit RF channel group delay information;

[0034] A device requirement information acquisition module, wherein the device requirement information acquisition module is used to acquire device requirement information;

[0035] The delay time acquisition module is used to obtain the DSP's external output Trigger Out signal delay time based on device demand information, trigger output delay information, trigger input delay information, transmission delay information between the DSP and DAC, the time required for the DAC to receive data and generate a waveform, and the transmission RF channel group delay information.

[0036] Beneficial effects:

[0037] This DSP-based method for acquiring the transmission delay of a trigger signal provides an automated delay calculation and configuration method. This method, integrated into the DSP, enables self-configuration of delays based on configuration modes. The delays can also be reported, facilitating cascading in complex systems. By calculating and statistically analyzing delays from various tests, a model is developed to analyze the delays of various components of a complete device. This model can then be modified through calculation and estimation, enabling its application to other similar or simplified products and devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a flowchart of a method for acquiring transmission delay of a trigger signal based on DSP in one embodiment of the present application.

[0039] Figure 2 It is the software interface for SI9000 to calculate the transmission speed of the surface line.

[0040] Figure 3 It is the software interface for SI9000 to calculate the transmission speed of inner layer wire.

[0041] Figure 4 It is a software interface for calculating via delay in PCB Design.

[0042] Figure 5 This is the schematic diagram of the Trigger Auto Seek circuit for signal source application in this application.

[0043] Figure 6 This is the schematic diagram of the Trigger Auto Seek circuit for a spectrum analyzer.

[0044] Figure 7This is the configuration flow chart of the Trigger delay time of this application.

[0045] Figure 8 It is a fitting diagram of the transmit RF channel group delay information of the present application. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solutions and advantages of the implementation of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below in conjunction with the drawings in the embodiments of this application. In the drawings, the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The described embodiments are part of the embodiments of this application, not all of the embodiments. The embodiments described below with reference to the drawings are exemplary and are intended to be used to explain this application, and should not be understood as limitations on this application. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. The embodiments of this application are described in detail below in conjunction with the drawings.

[0047] like Figure 1 The method for obtaining the transmission delay of a trigger signal based on DSP is characterized in that the method for obtaining the transmission delay of a trigger signal based on DSP includes:

[0048] Obtain the trigger output delay information of the transmitting RF drive frequency conversion circuit, the trigger input delay information, the transmission delay information between the DSP and DAC, the time required for the DAC to receive data and generate a waveform, and the transmitting RF channel group delay information;

[0049] Obtain equipment demand information;

[0050] The DSP's external output Trigger Out signal delay time is obtained based on the device requirement information, trigger output delay information, trigger input delay information, transmission delay information between the DSP and DAC, the time required for the DAC to receive data and generate a waveform, and the transmit RF channel group delay information.

[0051] This DSP-based method for acquiring the transmission delay of a trigger signal provides an automated delay calculation and configuration method. This method, integrated into the DSP, enables self-configuration of delays based on configuration modes. The delays can also be reported, facilitating cascading in complex systems. By calculating and statistically analyzing delays from various tests, a model is developed to analyze the delays of various components of a complete device. This model can then be modified through calculation and estimation, enabling its application to other similar or simplified products and devices.

[0052] In this embodiment, the device requirement information includes external Trigger In input control information and external Trigger In input control information;

[0053] When the device requirement information indicates that no external Trigger In input control information is required, the delay time of the DSP outputting the Trigger Out signal externally is obtained based on the device requirement information and the trigger output delay information, the trigger input delay information, the transmission delay information between the DSP and the DAC, the time required for the DAC to receive data and generate a waveform, and the transmit RF channel group delay information by using the following formula:

[0054] Ta=T5+T4+T3-T1; where

[0055] Ta is the delay time for the DSP to output the Trigger Out signal when the device requirement information is that no external Trigger In input control information is required; T5 is the delay information of the transmitting RF channel group; T4 is the time required for the DAC to receive data and generate a waveform; T3 is the transmission delay information between the DSP and DAC; T1 is the trigger output delay information.

[0056] In this embodiment, when the device requirement information is that external Trigger In input control information is required, the delay time of the DSP outputting the Trigger Out signal externally is obtained based on the device requirement information and the trigger output delay information, the trigger input delay information, the transmission delay information between the DSP and the DAC, the time required for the DAC to receive data and generate a waveform, and the transmit RF channel group delay information by using the following formula:

[0057] Tb=T5+T4+T3-T1+T2; where

[0058] Tb is the delay time for the DSP to output the Trigger Out signal when the device requires external Trigger In input control information; T5 is the delay information of the transmitting RF channel group; T4 is the time required for the DAC to receive data and generate a waveform; T3 is the transmission delay information between the DSP and DAC; T1 is the trigger output delay information; T2 is the trigger input delay information.

[0059] In this embodiment, the trigger output delay information is obtained by the following formula:

[0060] T1=l 表层线 *v 表层线 +l 内层线 *v 内层线 +t 过孔 ;

[0061] Among them, l表层线 Represents the length of the Trigger signal passing through the surface line, v 表层线 represents the propagation speed of the surface line; l 内层线 Represents the length of the inner line through which the Trigger signal passes, v 内层线 represents the propagation speed of the inner line; t 过孔 Represents the superposition of all the times passing through the via, which is Figure 4 The superposition of the step response times in .

[0062] In this embodiment, the transmit RF channel group delay information is obtained by the following formula:

[0063] Tinter=Tag_0+(freq_inter-freq_a)*[(Tag_b-Tag_a) / freq_b-freq_a)]; where Tinter is the transmit RF channel group delay information, freq_inter is the required frequency point, freq_a is the frequency of the previous calibration frequency point of the required frequency point, freq_b is the frequency of the next frequency point of the required frequency point, Tag_a and Tag_b are the delay time of the previous calibration frequency point and the next frequency point of the frequency point respectively. Through the two frequency points and time, the intermediate frequency point and the delay time can be linearly fitted, and Tag_0 can be obtained as the intercept of the linear fitting curve, such as Figure 8 shown.

[0064] The following is a detailed explanation of how to obtain T1, T2, T3, T4, and T5.

[0065] In this embodiment, the circuit board transmission delay calculation can be performed with the help of the circuit board EDA drawing tool and the Polar SI9000 tool, as well as other tools. 1) Measure the corresponding line length of the circuit board using the circuit board EDA drawing tool; 2) Then input the selected circuit board material parameters into the SI9000 software for calculation, such as Figure 2 、 Figure 3 As shown, the transmission speed of the surface line and the strip line can be obtained respectively. 3) Use the PCB Design tool to simulate and calculate the transmission delay of the via (or use other tools such as HFSS to simulate and calculate it), as shown Figure 4 As shown; 4) Calculate and superimpose them separately, and the total circuit board transmission delay can be obtained as follows:

[0066] t 总 =t 表层线 +t 内层线 +t 过孔 =l 表层线 *v 表层线 +l 内层线 *v 内层线+t 过孔 (Formula 1);

[0067] In this embodiment, T1 = Trigger Out Latency, trigger output delay information can be calculated by the line length of the circuit board, and the calculation formula is shown in the above formula 1 (in this case, t 总 equal to t1) and write it into the calibration data; and the TriggerOut output can be an external connector on the front panel, a PCIe interface on the backplane, or other reserved communication interfaces. It is only necessary to record the delay time of different interfaces separately in the calibration data to facilitate the call calculation.

[0068] In this embodiment, T2 = Trigger In Latency, trigger input delay information, the calculation formula is shown in the above formula 1 (at this time, t 总 = t2), which can be calculated by the line length of the circuit board, and the delay time of different interface inputs is measured and recorded in the calibration data.

[0069] In this embodiment, T3 = DSP to DAC Latency. Through the designed LVDS bus interface, the DSP adds a Data Marker to the waveform to identify the starting point of counting. The DSP initiates counting when sending data to the DAC and measures the number of clock cycles corresponding to the DAC's return status indication. This provides information on the transmission delay between the DSP and DAC. Furthermore, because the clock used between the DSP and DAC is 150MHz, and the designed LVDS interface is dual-edge triggered on both rising and falling edges, the actual clock can reach 300MHz, further improving test accuracy (the minimum delay accuracy is 300MHz cycles, and the test error can reach 600MHz cycles). This time can be measured in real time and cached in the DSP for easy access and use.

[0070] In this embodiment, T4=DAC Play Waveform Latency, which is the time required for the DAC to receive data and generate a waveform. This time can be given in the data sheet of the used DAC chip, and manual testing is unnecessary.

[0071] T5 = Tx RF Channel Group Delay, which indicates the transmit RF channel group delay. This parameter can be used to measure the time it takes for the entire device to complete configuration. Connect the transmit channel output to an oscilloscope and set it to Trigger In. The oscilloscope captures the time between the trigger signal being sent to the device and the frequency of the output signal stabilizing. This time is then deducted from T2, T3, and T4 and written into the calibration data.

[0072] Considering that in actual testing, signals of different frequencies exhibit jitter in the time domain due to phase noise, the captured group delay will fluctuate between tests, necessitating group delay correction. First, through testing, a series of test times, Tgd(group delay) = {t0, t1, …, tx}, are obtained. The maximum and minimum values ​​are removed, and the remaining data is averaged, i.e., Tag(average) = [sum{t0, t1, …, tx} - max{t0, t1, …, tx} - min{t0, t1, …, tx}] / (x - 1) (Equation 2).

[0073] In addition, since the group delay of different frequencies is different, the test process needs to test the group delay of different frequencies. Based on the characteristics of the RF channel (such as filter segmentation, frequency conversion segmentation, frequency multiplication segmentation, amplifier segmentation, etc.), a series of frequency sampling test points are calibrated, and the group delay of these test points is tested. The sampling frequency point set {freq_0, freq_1, ..., freq_x} can be mapped to the group delay time set {Tag_0, Tag_1, ..., Tag_x}.

[0074] In order to cover the frequency points that have not been tested, the DSP performs interpolation calculations. The above sampling frequency point set and group delay time set are stored in the DSP's storage unit Flash. In actual testing, the DSP reads the above data and adopts a linear interpolation method, assuming that the group delay time between adjacent sampling frequency points changes linearly. The delay time of the interpolation point is calculated based on the difference and delay time between the required frequency point freq_inter and the adjacent sampling frequency points (denoted as freq_a and freq_b), that is, Tinter = Tag_0 + (freq_inter-freq_a) * [(Tag_b-Tag_a) / freq_b-freq_a)] - (Equation 3);

[0075] For each configured frequency point, the group delay time is Tinter. When the configured frequency point is consistent with the sampling frequency point in the calibration data, it can be directly applied. In this way, the group delay time of the channel is corrected.

[0076] In summary, in actual testing, each delay time can be read into the DSP according to the configured test mode, and the delay time of the entire device in different test modes can be finally calculated to meet the needs of synchronous testing, which is more accurate and reliable.

[0077] If the device does not require external Trigger In input control and only needs to output the Trigger Out signal, the delay time Ta = T5 + T4 + T3 - T1, because the configured delay time needs to deduct the delay time of Trigger Out when it is output on the circuit board. After the host computer configures the device, the Trigger Out signal can be output after waiting for Ta. This can ensure that when the signal is output to the RF port, the Trigger Out signal is also output to the low-frequency port.

[0078] If the device requires external Trigger In input control, the delay time Tb = T5 + T4 + T3 - T1 + T2; after the external Trigger In input, the Trigger Out signal can be output after waiting for Tb.

[0079] In this embodiment, the DSP-based method for acquiring the transmission delay of the trigger signal further includes:

[0080] Obtain the receiving RF channel group delay information of the receiving RF driving frequency conversion circuit, the delay information of the ADC discretizing the input signal and routing the data output, the receiving transmission delay between the DSP and ADC, the receiving trigger output delay information, and the receiving trigger input delay information;

[0081] The delay time of the spectrum analyzer device is obtained based on the device requirement information, the receiving RF channel group delay information of the receiving RF driving frequency conversion circuit, the delay information of the ADC discretizing the input signal and routing the data output, the receiving transmission delay between the DSP and ADC, the receiving trigger output delay information, and the receiving trigger input delay information.

[0082] In this embodiment, when the device requirement information indicates that no external Trigger In input control information is required, the delay time of the spectrum analyzer device is obtained based on the device requirement information and the receiving RF channel group delay information of the receiving RF driving frequency conversion circuit, the delay information of the ADC discretizing the input signal and routing the data output, the receiving transmission delay between the DSP and the ADC, the receiving trigger output delay information, and the receiving trigger input delay information by using the following formula:

[0083] Tc=T15+T14+T13-T11; among them,

[0084] Tc is the delay time for the spectrum analyzer device when the device requirement information is that no external Trigger In input control information is required, T15 is the receiving trigger input delay information, T14 is the receiving trigger output delay information, T13 is the receiving transmission delay between DSP and ADC, and T11 is the receiving RF channel group delay information.

[0085] In this embodiment, when the device requirement information is that external Trigger In input control information is required, the delay time of the spectrum analyzer device is obtained according to the device requirement information and the receiving RF channel group delay information of the receiving RF driving frequency conversion circuit, the delay information of the ADC discretizing the input signal and routing the data output, the receiving transmission delay between the DSP and the ADC, the receiving trigger output delay information, and the receiving trigger input delay information by using the following formula:

[0086] Td=T15+T14+T13-T11+T12; among them,

[0087] Td is the delay time for the spectrum analyzer device when the device requirement information is that external Trigger In input control information is required, T15 is the delay information for receiving trigger input, T14 is the delay information for receiving trigger output, T13 is the receive transmission delay between DSP and ADC, T11 is the delay information for receiving RF channel group, and T12 is the delay information for ADC to discretize the input signal and route the data out.

[0088] The following explains in detail how to obtain T11, T12, T13, T14, and T15.

[0089] T11 = Rx RF Channel Group Delay, which receives RF channel group delay information. Connect an RF connector before the ADC input. Similar to signal source testing, use a test instrument to measure group delay at different frequencies and channel configurations. Similar to T5, this delay can be calibrated and stored in the DSP calibration data for application calculations.

[0090] T12 = ADC Data Router Latency. This parameter specifies the delay required for the ADC to discretize the input signal and route the data out. This information can be found in the data sheet of the ADC chip used, eliminating the need for manual testing.

[0091] T13 = ADC to DSP Latency. Through the designed LVDS bus interface, the DSP measures the number of clock cycles corresponding to the DAC obtaining the data return status indication, and the receiving transmission delay T13 between the DSP and ADC can be obtained.

[0092] T14 = Trigger Out Latency. The delay information for receiving the trigger output can be calculated based on the line length through the circuit board (Equation 1). The delay time of different interface outputs is measured separately and recorded in the calibration data.

[0093] T15 = Trigger In Latency. The delay information for receiving the trigger input can be calculated based on the line length of the circuit board (Equation 1). The delay time of different interface inputs is measured separately and recorded in the calibration data.

[0094] The delay calculation for a spectrum analyzer is similar to that for a signal source. If the device does not require external TriggerIn input control and only needs to output a TriggerOut signal, the delay time Tc = T15 + T14 + T13 - T11.

[0095] If the device requires external Trigger In input control, the delay time Td = T15 + T14 + T13 - T11 + T12; after the external Trigger In input, the Trigger Out signal can be output after waiting for Tb.

[0096] In this embodiment, the application of the present application to the signal source is as follows: Figure 5 As shown, the system includes a host computer, DDR, DSP, DAC, transmit RF drive frequency conversion circuit, and a DSP-to-DAC LVDS bus interface. Trigger In / Out signals can be sourced from external connectors or PCIe interfaces. The host computer provides user control of the entire device through an interface, while also providing data interaction functions such as waveform generation, status indication, and delay time reporting.

[0097] DDR (Double Data Rate SDRAM) is used for high-speed signal transmission between the host computer and DSP to facilitate fast data caching and interaction.

[0098] DSP, digital signal processing unit, responds to host computer instructions and controls the entire device, processes, distributes and reports data, and supports input and output responses to trigger signals.

[0099] DAC (Digital to Analog Converter) receives the waveform sent by DSP and generates the corresponding RF signal.

[0100] The transmitting RF drive frequency conversion circuit is composed of various analog devices such as amplifiers, attenuators, filters, mixers, etc., which performs RF processing on the signal generated by the DAC for external output.

[0101] The DSP to DAC LVDS bus interface (LVDS, Low Voltage Differential Signaling, has the characteristics of low voltage, low loss, and high speed) is a communication protocol designed for high-speed applications and can meet the requirements of high-speed data distribution and high-precision data testing.

[0102] exist Figure 5 In the illustrated embodiment, the host computer PC issues instructions, which are transmitted to the DSP via the DDR chip; the DSP sends configuration and waveform files to the DAC via the LVDS bus, receives an external Trigger In signal, and outputs a Trigger Out signal; the DAC converts the digital signal into an intermediate frequency signal based on the configuration and waveform; the transmitting RF drive frequency conversion circuit converts the intermediate frequency signal output by the DAC into an RF signal through frequency conversion, amplification, attenuation, filtering and other circuits.

[0103] In this embodiment, for the use of the spectrum analyzer, a DSP-based Trigger Auto Seek (waveform and trigger signal automatic synchronization mechanism / method) solution can be as follows: Figure 6 As shown, it includes: host computer, DDR, DSP, ADC, receiving RF drive frequency conversion circuit, DSP to DAC LVDS bus interface. It is similar to the application of signal source, except that the DAC is changed to ADC and the transmitting RF drive circuit is changed to the receiving RF drive circuit. Figure 6 In the process, the external RF signal is received by the RF drive frequency conversion circuit, and then outputs the intermediate frequency signal to the ADC after filtering, amplification, attenuation, and frequency conversion circuit; the ADC samples the input intermediate frequency signal, converts it into corresponding waveform data and sends it to the DSP; the DSP receives the input waveform data, performs some digital filtering, extraction and other digital signal processing, and then transmits the data to the host PC through the DDR chip.

[0104] The ADC (Analog to Digital Converter) receives the intermediate frequency signal output by the RF drive frequency conversion circuit and performs discretization processing to obtain the corresponding data information, and then outputs it to the DSP.

[0105] The receiving RF drive frequency conversion circuit is composed of various analog devices such as amplifiers, attenuators, filters, mixers, etc. It converts the external input RF signal into a signal of frequency band and power that can be analyzed by ADC, and then outputs it to the ADC.

[0106] like Figure 7As shown, different trigger mode configurations are adopted to adapt to different applications. Within the DSP, these can be achieved: the delay time embedded in the calibration data is read automatically, the data delay between the DSP and the ADC / DAC is tested and cached in the DSP, and the delay time of the trigger signal is configured according to the usage mode to achieve the highest possible synchronization between the Trigger Out status indicator signal and the RF signal output. The DSP reads the RF channel group delay time from the data and calculates the group delay time at the corresponding configured frequency point through linear interpolation. This delay time can also be reported to the host computer through the DSP. It can also be applied in complex RF communication systems, enabling joint control with other devices within the system to meet different usage scenarios.

[0107] This application has the following advantages:

[0108] To meet the needs of synchronous testing, a TriggerAuto Seek solution has been designed for use with signal sources and spectrum analyzers. This method automatically calculates and configures delay time and integrates it into the DSP, enabling automatic delay time configuration based on the configuration mode. Delay time can be reported, facilitating cascading in complex systems.

[0109] 2. By calculating and statistically analyzing the delay times of different tests, a model for analyzing the delays of each part of the complete device is summarized. With the help of calculation and estimation, the model is modified and can be applied to other similar or simplified products and devices.

[0110] 3. A linear interpolation calculation method for group delay time is added to DSP to correct the group delay time to improve the test accuracy of the group delay time. It also covers the frequency points of uncalibrated tests, improves applicability, and reduces the difficulty, time and labor costs of calibration tests.

[0111] The present application also provides a transmission delay acquisition device for a trigger signal based on a DSP, the transmission delay acquisition device for a trigger signal based on a DSP comprises an acquisition module, a device requirement information acquisition module, and a delay time acquisition module.

[0112] The acquisition module is used to obtain the trigger output delay information of the transmission radio frequency driving frequency conversion circuit, the trigger input delay information, the transmission delay information between the DSP and the DAC, the time required for the DAC to receive data and generate a waveform, and the transmission radio frequency channel group delay information;

[0113] The device requirement information acquisition module is used to acquire device requirement information;

[0114] The delay time acquisition module is used to obtain the DSP's external output Trigger Out signal delay time based on device requirement information, trigger output delay information, trigger input delay information, transmission delay information between DSP and DAC, the time required for DAC to receive data and generate a waveform, and transmitting RF channel group delay information.

[0115] Although the present invention has been described in detail above using general descriptions and specific embodiments, it will be apparent to those skilled in the art that modifications and improvements may be made based on the present invention. Therefore, such modifications and improvements, which do not depart from the spirit of the present invention, are intended to be within the scope of protection claimed herein.

Claims

1. A method for acquiring the transmission delay of a trigger signal based on DSP, characterized in that: The DSP-based method for acquiring the transmission delay of the Trigger signal includes: Obtain the trigger output delay information of the transmitting RF drive frequency conversion circuit, the trigger input delay information, the transmission delay information between the DSP and DAC, the time required for the DAC to receive data and generate a waveform, and the transmitting RF channel group delay information; Obtain equipment demand information; The DSP's external output Trigger Out signal delay time is obtained based on the device requirement information, trigger output delay information, trigger input delay information, transmission delay information between the DSP and DAC, the time required for the DAC to receive data and generate a waveform, and the transmit RF channel group delay information.

2. The method for acquiring the transmission delay of a trigger signal based on DSP according to claim 1, wherein: The device requirement information includes external Trigger In input control information and external Trigger In input control information; When the device requirement information indicates that no external Trigger In input control information is required, the delay time of the DSP outputting the Trigger Out signal externally is obtained based on the device requirement information, the trigger output delay information, the trigger input delay information, the transmission delay information between the DSP and the DAC, the time required for the DAC to receive data and generate a waveform, and the transmit RF channel group delay information by using the following formula: Ta=T5+T4+T3-T1; where Ta is the delay time for the DSP to output the Trigger Out signal when the device requirement information is that no external Trigger In input control information is required; T5 is the delay information of the transmitting RF channel group; T4 is the time required for the DAC to receive data and generate a waveform; T3 is the transmission delay information between the DSP and DAC; T1 is the trigger output delay information.

3. The method for acquiring the transmission delay of a trigger signal based on DSP according to claim 2, wherein: When the device requirement information requires external Trigger In input control information, the delay time of the DSP outputting the Trigger Out signal externally is obtained according to the device requirement information, the trigger output delay information, the trigger input delay information, the transmission delay information between the DSP and the DAC, the time required for the DAC to receive data and generate a waveform, and the transmit RF channel group delay information by using the following formula: Tb=T5+T4+T3-T1+T2; where Tb is the delay time for the DSP to output the TriggerOut signal when the device requires external TriggerIn input control information; T5 is the delay information of the transmitting RF channel group; T4 is the time required for the DAC to receive data and generate a waveform; T3 is the transmission delay information between the DSP and the DAC; T1 is the trigger output delay information; and T2 is the trigger input delay information.

4. The method for acquiring the transmission delay of a trigger signal based on DSP according to claim 3, wherein: The trigger output delay information is obtained by the following formula: ;in, Represents the length of the Trigger signal passing through the surface line, represents the propagation speed of the surface line; Represents the length of the inner line through which the Trigger signal passes. represents the propagation speed of the inner line; Represents the sum of all times traveling through the via.

5. The method for acquiring the transmission delay of a trigger signal based on DSP according to claim 4, wherein: The transmit RF channel group delay information is obtained by the following formula: Tinter=Tag_0+(freq_inter-freq_a)*[(Tag_b-Tag_a) / freq_b-freq_a)]; where Tinter is the transmit RF channel group delay information, freq_inter is the desired frequency point, freq_a is the frequency of the previous calibration frequency point of the desired frequency point, freq_b is the frequency of the next frequency point of the desired frequency point, Tag_a and Tag_b are the delay times of the previous calibration frequency point and the next frequency point of the frequency point, respectively; Tag_0 is the intercept obtained by the linear fitting curve.

6. The method for acquiring the transmission delay of a trigger signal based on DSP according to claim 5, wherein: The DSP-based method for acquiring the transmission delay of the Trigger signal further includes: Obtaining the receiving RF channel group delay information of the receiving RF driving frequency conversion circuit, the delay information of the ADC discretizing the input signal and outputting the data, the receiving transmission delay between the DSP and the ADC, the receiving trigger output delay information, and the receiving trigger input delay information; The delay time of the spectrum analyzer device is obtained based on the device requirement information, the receiving RF channel group delay information of the receiving RF driving frequency conversion circuit, the delay information of the ADC discretizing the input signal and routing the data output, the receiving transmission delay between the DSP and the ADC, the receiving trigger output delay information and the receiving trigger input delay information.

7. The method for acquiring the transmission delay of a trigger signal based on DSP according to claim 6, wherein: When the device requirement information indicates that no external Trigger In input control information is required, the delay time of the spectrum analyzer device is obtained according to the device requirement information and the receiving RF channel group delay information of the receiving RF driving frequency conversion circuit, the delay information of the ADC discretizing the input signal and routing the data output, the receiving transmission delay between the DSP and the ADC, the receiving trigger output delay information, and the receiving trigger input delay information by using the following formula: Tc=T12+T14+T13-T11; where Tc is the delay time for the spectrum analyzer device when the device requirement information indicates that no external Trigger In input control information is required, T12 is the delay information for the ADC to discretize the input signal and output the data, T14 is the receive trigger output delay information, T13 is the receive transmission delay between the DSP and ADC, and T11 is the receive RF channel group delay information.

8. The method for acquiring the transmission delay of a trigger signal based on DSP according to claim 7, wherein: When the device requirement information is that external Trigger In input control information is required, the delay time of the spectrum analyzer device is obtained according to the device requirement information and the receiving RF channel group delay information of the receiving RF driving frequency conversion circuit, the delay information of the ADC discretizing the input signal and routing the data output, the receiving transmission delay between the DSP and the ADC, the receiving trigger output delay information, and the receiving trigger input delay information by using the following formula: Td=T15+T14+T13-T11+T12; where Td is the delay time for the spectrum analyzer device when the device requirement information is that external Trigger In input control information is required, T15 is the delay information for receiving trigger input, T14 is the delay information for receiving trigger output, T13 is the receive transmission delay between DSP and ADC, T11 is the delay information for receiving RF channel group, and T12 is the delay information for ADC to discretize the input signal and output data.

9. A DSP-based Trigger signal transmission delay acquisition device, characterized in that: The DSP-based Trigger signal transmission delay acquisition device includes: An acquisition module is used to obtain trigger output delay information of the transmitting RF driving frequency conversion circuit, trigger input delay information, transmission delay information between the DSP and DAC, time required for the DAC to receive data and generate a waveform, and transmit RF channel group delay information; A device requirement information acquisition module, wherein the device requirement information acquisition module is used to acquire device requirement information; The delay time acquisition module is used to obtain the DSP's external output Trigger Out signal delay time based on device demand information, trigger output delay information, trigger input delay information, transmission delay information between the DSP and DAC, the time required for the DAC to receive data and generate a waveform, and the transmission RF channel group delay information.

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