Sigma-delta modulated dac based quantization perturbation method and apparatus

Abstract

The application discloses a quantization disturbance method and device based on a Sigma-Delta modulation DAC, which comprises the following steps: calculating the difference between a determined modulation signal and a determined feedback signal as a target signal, and performing a preprocessing operation on the target signal to obtain an integral signal, wherein the preprocessing operation comprises integral processing; performing a quantization operation on the integral signal to obtain a target disturbance modulation signal, wherein the target disturbance modulation signal is used as a disturbance modulation signal of the DAC. It can be seen that, by performing integral processing on the calculated signal and performing a quantization operation on the signal after the integral processing, the accurate disturbance modulation signal used for disturbing the DAC can be obtained, the randomness of the quantization code word of the disturbance modulation signal is enhanced, the SFDR performance of the DAC is improved, the stray radiation of the DAC is ensured, the application is not dependent on the specific implementation structure of the DAC, has higher universality, and can be used simultaneously with DEM.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of communication technology, and in particular to a quantization perturbation method and device based on Sigma-Delta modulation DAC. BACKGROUND

[0002] Currently, in order to avoid the use of large capacitance to save the DAC chip area, the commercial low-cost transmitter often uses digital up-sampling technology to up-sample the baseband waveform into a high-over-sampling digital intermediate frequency waveform, and then sends it to a high-speed DAC. The harmonic components of the high-speed DAC are far away from the baseband signal, so that the DAC chip area can be saved by connecting a wide and low-order analog filter behind the DAC. However, it is found in practice that this method significantly increases the demand for the spurious-free dynamic range SFDR performance of the DAC.

[0003] Currently, the common methods to improve the SFDR performance of the DAC include: 1. Narrowing the bandwidth of the analog filter behind the DAC as much as possible under the condition that the DAC chip area will not be significantly increased, and ensuring high linearity of the DAC; 2. Estimating the error of each code word of the DAC, and pre-compensating the error of each code word to the digital signal at the input end of the DAC; 3. Converting the estimated code word error to the analog domain based on the auxiliary DAC constructed, and then superimposing it on the target signal to obtain a high-precision analog waveform; 4. Mapping the binary code to the decoding logic of the thermometer code based on the DEM (dynamic element matching) technology, and finally randomizing and equalizing the adaptation error of the DAC circuit elements to improve the SFDR performance.

[0004] However, it is found in practice that it is difficult and costly to rely on careful design of the DAC to ensure its performance within the minimum required specifications; the method of pre-compensating the DAC code word error in the digital domain requires a complex DAC error estimation scheme and a complex pre-compensation circuit, which is difficult to implement; the method of using an auxiliary DAC requires estimating the DAC error and additionally constructing an auxiliary DAC circuit, which is complex; and the DEM technology requires joint design with the DAC structure, which requires the DAC to use an inefficient thermometer code structure, increasing the control complexity and manufacturing cost of the DAC. Therefore, it is particularly important to improve the SFDR performance of the DAC to ensure the spurious radiation of the DAC while ensuring low cost. SUMMARY

[0005] The technical problem solved by the present application is to provide a quantization disturbance method and device based on Sigma-Delta modulation DAC, which can improve the SFDR performance of the DAC to ensure the stray radiation of the DAC at low cost.

[0006] To solve the above technical problem, the first aspect of the embodiment of the present application discloses a quantization disturbance method based on Sigma-Delta modulation DAC, which comprises the following steps:

[0007] The difference between the determined modulation signal and the determined feedback signal is calculated as a target signal, and a pre-processing operation is performed on the target signal to obtain an integral signal, wherein the pre-processing comprises integral processing;

[0008] A quantization operation is performed on the integral signal to obtain a target disturbance modulation signal, which is used as a disturbance modulation signal of the DAC.

[0009] The width of the bit of the target disturbance modulation signal is less than or equal to the width of the bit of the modulation signal, and the width of the bit of the target disturbance modulation signal is greater than or equal to 1.

[0010] As an optional implementation, in the first aspect of the embodiment of the present application, the quantization operation performed on the integral signal to obtain a target disturbance modulation signal comprises:

[0011] A bidirectional quantization operation is performed on the integral signal and the obtained disturbance signal to obtain a first quantization signal and a second quantization signal.

[0012] A target quantization signal is determined based on the obtained control signal as a target disturbance modulation signal, wherein the target quantization signal is the first quantization signal or the second quantization signal, and the disturbance signal and the control signal are random sequences of different bases.

[0013] As an optional implementation, in the first aspect of the embodiment of the present application, the method further comprises:

[0014] A target disturbance signal and a target control signal are generated, and the target disturbance signal is determined as the obtained disturbance signal and the target control signal is determined as the obtained control signal, and the operation of performing the bidirectional quantization operation on the integral signal and the obtained disturbance signal to obtain the first quantization signal and the second quantization signal is triggered.

[0015] As an optional implementation, in the first aspect of the embodiment of the present application, the method further comprises:

[0016] acquire a real-time disturbance modulation signal, and perform a weighting operation on the acquired real-time disturbance modulation signal and the acquired impulse response signal to obtain a weighted signal, and determine the weighted signal as a determined feedback signal, and trigger the operation of calculating a difference between the determined modulation signal and the determined feedback signal as a target signal.

[0017] As an optional implementation, after the operation of performing a preprocessing operation on the target signal to obtain an integral signal, and before the operation of performing a quantization operation on the integral signal to obtain a target disturbance modulation signal, which is used as a disturbance modulation signal of the DAC, the method further comprises:

[0018] determining whether the integral signal satisfies a determined data analysis condition;

[0019] when it is determined that the data analysis condition is satisfied, triggering the operation of performing a quantization operation on the integral signal to obtain a target disturbance modulation signal, which is used as a disturbance modulation signal of the DAC;

[0020] when it is determined that the data analysis condition is not satisfied, performing a filtering operation on the integral signal to obtain the integral signal satisfying the data analysis condition;

[0021] wherein the operation of performing a quantization operation on the integral signal to obtain a target disturbance modulation signal, which is used as a disturbance modulation signal of the DAC, comprises:

[0022] the operation of performing a quantization operation on the integral signal satisfying the data analysis condition to obtain a disturbance modulation signal of the DAC.

[0023] The second aspect of the embodiment of the present application discloses a quantization disturbance device based on a Sigma-Delta modulation DAC, the device comprises a subtractor, a quantizer and a loop filter, and an output end of the device is electrically connected with an input end of a data processor, the data processor comprises the DAC, and wherein:

[0024] the subtractor is used to calculate a difference between a determined modulation signal and a determined feedback signal as a target signal, and transmit the target signal to the loop filter;

[0025] the loop filter is used to receive the target signal from the subtractor, perform a preprocessing operation on the target signal to obtain an integral signal, and transmit the integral signal to the quantizer, and the preprocessing comprises an integral processing;

[0026] The quantizer is configured to receive the integrated signal from the loop filter, and perform a quantization operation on the integrated signal to obtain a target dither modulation signal, which is used as a dither modulation signal of the DAC, wherein a bit width of the target dither modulation signal is less than or equal to a bit width of the modulation signal and greater than or equal to 1.

[0027] As an optional implementation, in the second aspect of the embodiment of the present application, the quantizer comprises a bidirectional quantizer and a selector, wherein:

[0028] The bidirectional quantizer is configured to perform a bidirectional quantization operation on the integrated signal and an obtained dither signal to obtain a first quantization signal and a second quantization signal, and transmit the first quantization signal and the second quantization signal to the selector.

[0029] The selector is configured to receive the first quantization signal and the second quantization signal transmitted by the bidirectional quantizer, and determine a target quantization signal based on an obtained control signal, as a target dither modulation signal, wherein the target quantization signal is the first quantization signal or the second quantization signal, and the dither signal and the control signal are random sequences of different bases.

[0030] As an optional implementation, in the second aspect of the embodiment of the present application, the quantizer further comprises a pseudo-random sequence generator, wherein:

[0031] The pseudo-random sequence generator is configured to generate a target dither signal and a target control signal, transmit the target dither signal to the bidirectional quantizer, and transmit the target control signal to the selector.

[0032] The bidirectional quantizer is further configured to receive the target dither signal transmitted by the pseudo-random sequence generator as the obtained dither signal, and trigger the operation of performing the bidirectional quantization operation on the integrated signal and the obtained dither signal to obtain the first quantization signal and the second quantization signal.

[0033] The selector is further configured to receive the target control signal transmitted by the pseudo-random sequence generator as the obtained control signal, and trigger the operation of determining the target quantization signal based on the obtained control signal as the target dither modulation signal.

[0034] As an optional implementation, in the second aspect of the embodiment of the present application, the apparatus further comprises a weighting filter, wherein:

[0035] The weighting filter is configured to acquire a real-time disturbance modulation signal, and perform a weighting operation on the acquired real-time disturbance modulation signal and the acquired impulse response signal to obtain a weighted signal, and transmit the weighted signal to the subtractor.

[0036] The subtractor is further configured to receive the weighted signal transmitted by the weighting filter as a determined feedback signal, and trigger the operation of calculating a difference between the determined modulation signal and the determined feedback signal as a target signal.

[0037] As an optional implementation, in the second aspect of the embodiment of the present application, the loop filter is further configured to, after performing a preprocessing operation on the target signal to obtain an integral signal, judge whether the integral signal satisfies a determined data analysis condition; when it is judged that the data analysis condition is satisfied, transmit the integral signal to the quantizer to trigger the quantizer to perform the operation of receiving the integral signal from the loop filter and performing a quantization operation on the integral signal to obtain a target disturbance modulation signal, which is used as the DAC disturbance modulation signal; when it is judged that the data analysis condition is not satisfied, perform a filtering operation on the integral signal, and transmit the integral signal satisfying the data analysis condition to the quantizer.

[0038] The quantizer is further configured to receive the integral signal satisfying the data analysis condition transmitted by the loop filter, and perform a quantization operation on the integral signal satisfying the data analysis condition to obtain a target disturbance modulation signal, which is used as the DAC disturbance modulation signal.

[0039] The third aspect of the present application discloses another Sigma-Delta modulation DAC-based quantization disturbance device, which comprises:

[0040] a memory in which an executable program code is stored;

[0041] a processor coupled with the memory;

[0042] The processor invokes the executable program code stored in the memory to execute the Sigma-Delta modulation DAC-based quantization disturbance method disclosed in the first aspect of the present application.

[0043] The fourth aspect of the present application discloses a computer storage medium, which stores computer instructions, and the computer instructions are used to execute the Sigma-Delta modulation DAC-based quantization disturbance method disclosed in the first aspect of the present application when invoked.

[0044] Compared with the prior art, the embodiment of the present application has the following beneficial effects:

[0045] In the embodiment of the present application, a Sigma-Delta modulation DAC-based quantization disturbance method and device are disclosed. The method comprises calculating the difference between the determined modulation signal and the determined feedback signal as a target signal, and performing a preprocessing operation on the target signal to obtain an integral signal. The preprocessing comprises integral processing. A quantization operation is performed on the integral signal to obtain a target disturbance modulation signal, which is used as a disturbance modulation signal of the DAC. The bit width of the target disturbance modulation signal is less than or equal to the bit width of the modulation signal, and the bit width of the target disturbance modulation signal is greater than or equal to 1. As can be seen, the embodiment of the present application can obtain an accurate disturbance modulation signal for disturbing the DAC by performing integral processing on the calculated signal and performing a quantization operation on the signal after integral processing, and the randomness of the quantization code word of the disturbance modulation signal is enhanced, the SFDR performance of the DAC is improved, the spurious radiation of the DAC is ensured, and the DAC does not depend on the specific implementation structure, has higher universality, can be used with DEM at the same time, and does not need to estimate the error of the DAC, that is, does not need to construct a complex DAC circuit, which is beneficial to reducing the control complexity of the DAC. BRIEF DESCRIPTION OF DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0047] Figure 1 is a flow diagram of a Sigma-Delta modulation DAC-based quantization disturbance method disclosed by the embodiment of the present application;

[0048] Figure 2 is a flow diagram of another Sigma-Delta modulation DAC-based quantization disturbance method disclosed by the embodiment of the present application;

[0049] Figure 3 is a structural diagram of a Sigma-Delta modulation DAC-based quantization disturbance device disclosed by the embodiment of the present application;

[0050] Figure 4 is a structural diagram of another Sigma-Delta modulation DAC-based quantization disturbance device disclosed by the embodiment of the present application;

[0051] Figure 5is a structural schematic diagram of another quantization perturbation device based on Sigma-Delta modulation DAC disclosed by the embodiment of the present application;

[0052] Figure 6 is a schematic diagram of a principle for generating a perturbation modulation signal of a DAC disclosed by the embodiment of the present application;

[0053] Figure 7 is a schematic diagram of a random quantizer disclosed by the embodiment of the present application. DETAILED DESCRIPTION

[0054] In order to make the personnel in the art better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by the person of ordinary skill in the art without creative labor fall within the protection scope of the present application.

[0055] The terms "first", "second", and the like in the specification and claims of the present application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, device, product or equipment including a series of steps or units is not limited to the listed steps or units, but can optionally include steps or units not listed or can optionally include other steps or units inherent to the process, method, product or equipment.

[0056] In this document, the term "embodiment" means that the specific features, structures or characteristics described in connection with the embodiment can be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily mean the same embodiment, nor is it independent or alternative to other embodiments. The person skilled in the art explicitly and implicitly understands that the embodiments described herein can be combined with other embodiments.

[0057] The application discloses a quantization disturbance method and device based on a Sigma-Delta modulation DAC, which can obtain an accurate disturbance modulation signal for disturbing the DAC by performing integral processing on a calculated signal and performing quantization operation on the integral processed signal, and can enhance the randomness of the quantization code word of the disturbance modulation signal, improve the SFDR performance of the DAC, ensure the stray radiation of the DAC, and has higher universality, can be used simultaneously with DEM, and does not depend on the specific implementation structure of the DAC.

[0058] Embodiment one

[0059] Please refer to Figure 1 , Figure 1 is a flowchart of a quantization disturbance method based on a Sigma-Delta modulation DAC disclosed by the embodiment of the application, wherein the quantization disturbance method based on the Sigma-Delta modulation DAC is applied to a quantization disturbance system, as shown in Figure 1 The quantization disturbance method based on the Sigma-Delta modulation DAC can include the following operations:

[0060] 101, calculate the difference between the determined modulation signal and the determined feedback signal as a target signal.

[0061] In the embodiment of the application, the modulation signal and the feedback signal enter the subtracter in the form of a data stream, and the difference between the modulation signal and the feedback signal is calculated based on the subtracter as a target signal. The feedback signal can be pre-set and fixed, or can be real-time changeable. Further, the feedback signal can be derived from a weighted filter. The weighted filter can include an FIR filter and / or an IIR filter.

[0062] 102, perform a preprocessing operation on the target signal to obtain an integral signal, and the preprocessing includes integral processing.

[0063] In the embodiment of the application, the preprocessing operation is performed on the target signal in the loop filter to obtain the integral signal. The order of the loop filter is greater than or equal to 1, that is, the loop filter can include a first-order filter or a second-order filter or a high-order filter. It should be noted that the higher the order of the loop filter, the higher the accuracy of the disturbance modulation signal of the DAC.

[0064] 103, perform quantization operation on the integral signal to obtain a target disturbance modulation signal, and the target disturbance modulation signal is used as the disturbance modulation signal of the DAC.

[0065] In the embodiment of the present application, the width of the bit of the perturbation modulation signal is less than or equal to the width of the bit of the modulation signal and greater than or equal to 1.

[0066] In the embodiment of the present application, the integral signal is analyzed in the quantizer (random quantizer) to obtain the perturbation modulation signal of the DAC, which can enhance the randomness of the quantization code word of the modulation signal and is beneficial to improve the SFDR function of the DAC.

[0067] In the embodiment of the present application, it should be noted that the target perturbation modulation signal can be directly transmitted to the DAC or processed by other processing modules (for example, a digital shaping filter) and then transmitted to the DAC, and the embodiment of the present application is not limited.

[0068] It can be seen that the implementation Figure 1 The described quantization perturbation method based on the Sigma-Delta modulation DAC can obtain the accurate perturbation modulation signal for perturbing the DAC by performing the integral processing on the calculated signal and performing the quantization operation on the signal after the integral processing, and can enhance the randomness of the quantization code word of the perturbation modulation signal, improve the SFDR performance of the DAC, ensure the spurious radiation of the DAC, and does not depend on the specific implementation structure of the DAC, has higher universality, can be used with DEM at the same time, and does not need to estimate the error of the DAC, that is, does not need to construct a complex DAC circuit, which is beneficial to reduce the control complexity of the DAC.

[0069] In an optional embodiment, the integral signal is subjected to a quantization operation to obtain a target perturbation modulation signal, and the target perturbation modulation signal is used as the perturbation modulation signal of the DAC, which comprises:

[0070] The integral signal and the obtained perturbation signal are subjected to a bidirectional quantization operation to obtain a first quantization signal and a second quantization signal.

[0071] The target quantization signal is determined based on the obtained control signal as the target perturbation modulation signal, the target quantization signal is the first quantization signal or the second quantization signal, and the perturbation signal and the control signal are random sequences of different bases.

[0072] In the optional embodiment, the quantizer comprises a bidirectional quantizer and a selector, wherein the disturbance signal can be pre-stored in the bidirectional quantizer or come from a pseudo-random sequence generator. The control signal can be pre-stored in the selector or come from a pseudo-random sequence generator. Further, the selection flag of the quantization signal is set for the control signal in advance, different quantization signals correspond to different selection flags, and the association between different selection flags and corresponding quantization signals is established in advance. For example, the selection flag of the control signal can be set as 0 and 1, wherein the selection flag 0 corresponds to the A quantization signal, and the selection flag 1 corresponds to the B quantization signal. When the selection flag is 0, the A quantization signal is selected as the disturbance modulation signal of the DAC, and when the selection flag is 1, the B quantization signal is selected as the disturbance modulation signal of the DAC. In this way, by establishing the association between the quantization signal and the selection flag of the control signal, the corresponding quantization signal can be selected as the disturbance modulation signal of the DAC according to the selection flag of the control signal, thereby improving the selection accuracy and efficiency of the disturbance modulation signal of the DAC.

[0073] It should be noted that, under the control of the control signal, whether the first quantization signal or the second quantization signal is selected as the disturbance modulation signal of the DAC is random, that is, the disturbance modulation signal of the DAC at the current time can be the first quantization signal, the disturbance modulation signal of the DAC at the next time can still be the first quantization signal or change to the second quantization signal, which is beneficial to improve the randomness of the selection of the disturbance modulation signal of the DAC.

[0074] In the optional embodiment, the bidirectional quantization operation is performed on the integral signal and the obtained disturbance signal in the bidirectional quantizer to obtain the first quantization signal and the second quantization signal, and the first quantization signal and the second quantization signal are input into the selector, and one of the quantization signals is selected as the disturbance modulation signal of the DAC under the control of the control signal. The bit width (quantization bit width) of the first quantization signal and the second quantization signal can be the same or different.

[0075] In the optional embodiment, the calculation formulas of the first quantization signal and the second quantization signal are as follows:

[0076]

[0077]

[0078] In the formula, c+j is the integral signal, y is the bit width of the quantization signal, and the down-rounding operation is used to quantize the data c+j into the quantization signal with the bit width y. In the formula, c+j is the integral signal, y is the bit width of the quantization signal, and the down-rounding operation is used to quantize the data c+j into the quantization signal with the bit width y. represents quantizing data c+j to a y-bit-width quantization signal using a rounding-up operation, f represents a first quantization signal, g represents a second quantization signal, c represents an integral signal, j represents a disturbance signal, and y represents a bit width of a disturbance modulation signal of a DAC.

[0079] It can be seen that the optional embodiment can realize the acquisition of the disturbance modulation signal for the disturbance DAC by acquiring two quantization signals based on the disturbance signal and selecting one of the quantization signals under the control of the control signal, improve the acquisition accuracy and reliability of the disturbance modulation signal, thereby acquiring a random quantization disturbance signal, and further reduce the quasi-periodic probability of the signal in the DAC, further improve the SFDR performance of the DAC, and further ensure the stray radiation of the DAC.

[0080] In another optional embodiment, the quantization disturbance method based on the Sigma-Delta modulation DAC can further include the following operations:

[0081] The target disturbance signal and the target control signal are generated, and it is determined that the target disturbance signal is the acquired disturbance signal and the target control signal is the acquired control signal, and the operation of performing bidirectional quantization on the integral signal and the acquired disturbance signal to obtain the first quantization signal and the second quantization signal is triggered.

[0082] In the optional embodiment, the pseudo-random sequence generator generates the target disturbance signal and the target control signal by using the determined signal generation method. The signal generation method includes but is not limited to a linear feedback shift register method, a Mersenne rotation algorithm, and a congruence algorithm that can generate random signals.

[0083] In the optional embodiment, optionally, the target disturbance signal is a first multi-ary (for example, a six-ary) random number sequence, and the target control signal is a second multi-ary (for example, a binary) random number sequence.

[0084] It can be seen that the optional embodiment generates real-time control signals and disturbance signals that match the current state of the DAC by using the pseudo-random sequence generator, which is beneficial to improve the acquisition efficiency and accuracy of the quantization signal, thereby improving the generation accuracy and reliability of the disturbance modulation signal for modulating the DAC, and further improving the SFDR performance of the DAC to ensure the stray radiation of the DAC.

[0085] In yet another optional embodiment, after generating the target disturbance signal and the target control signal, the quantization disturbance method based on the Sigma-Delta modulation DAC can further include the following operations:

[0086] acquire a bit width of the signal, and determine whether the bit width of the signal is a required bit width, wherein the signal is a target disturbance signal and / or a target control signal;

[0087] when it is determined that the bit width is the required bit width, trigger the operation of determining that the target disturbance signal is the acquired disturbance signal and the target control signal is the acquired control signal;

[0088] when it is determined that the bit width is not the required bit width, perform bit width processing on the bit width of the signal to make the bit width of the signal the required bit width, and trigger the operation of determining that the target disturbance signal is the acquired disturbance signal and the target control signal is the acquired control signal.

[0089] It can be seen that, in the optional embodiment, when the disturbance signal of the disturbance integral signal and the control signal of the disturbance modulation signal of the selected DAC are acquired, it is first determined whether the bit width is the required bit width, and if not, bit width processing is performed to obtain a bit width that meets the requirement, which can further improve the acquisition efficiency and accuracy of the quantization signal, thereby improving the generation accuracy and reliability of the disturbance modulation signal used to modulate the DAC, and further improving the SFDR performance of the DAC to ensure the spurious radiation of the DAC.

[0090] In yet another optional embodiment, before step 101 is performed, the quantization disturbance method based on the Sigma-Delta modulated DAC can further include the following operations:

[0091] acquire a real-time disturbance modulation signal, perform weighting operation on the acquired real-time disturbance modulation signal and the acquired impulse response signal to obtain a weighted signal, determine the weighted signal as the determined feedback signal, and trigger the operation of calculating the difference between the determined modulation signal and the determined feedback signal as the target signal.

[0092] In the optional embodiment, the acquired real-time disturbance modulation signal and the acquired impulse response signal are weighted in the weighting filter to obtain a weighted signal, and the weighted signal is determined as the determined feedback signal. The initial value of the real-time disturbance modulation signal can be 0 or a non-0 value. After the target disturbance modulation signal is generated, the real-time disturbance modulation signal can be the target disturbance modulation signal, that is, when the target disturbance modulation signal is generated, it is divided into two parts, one part is used as the real-time disturbance modulation signal of the weighting filter, and the other part is used as the disturbance modulation signal of the DAC.

[0093] In the optional embodiment, since the disturbance modulation signal of the DAC is real-time, a part of the disturbance modulation signal of the DAC is transmitted to the weighting filter to realize real-time acquisition of the feedback signal.

[0094] In the optional embodiment, the perturbation modulation signal d of the DAC is:

[0095]

[0096]

[0097]

[0098] wherein d is the perturbation modulation signal of the DAC; n represents the perturbation error introduced by the stochastic quantizer; l represents the impulse response signal of the loop filter, represents convolution operation, a represents the acquired modulation signal, e represents the acquired feedback signal; w represents the impulse response signal of the weighted filter;

[0099] In the optional embodiment, according to the above formula, the perturbation modulation signal d of the DAC is:

[0100]

[0101] In the optional embodiment, the stochastic quantizer can adjust the random value of the perturbation modulation signal d between the first quantization signal and the second quantization signal by generating the perturbation signal j and the control signal h, so as to realize the perturbation function, that is, realize the random perturbation of the DAC.

[0102] In the optional embodiment, the weighted filter can shape the additional quantization noise, that is, the perturbation error n, brought by the stochastic quantizer by adjusting w, so as to make the quantization noise power match the determined frequency range (for example: 1500Hz-2600Hz), thereby reducing the influence of the quantization noise on the target perturbation modulation signal, that is, being conducive to obtaining the target perturbation modulation signal with high precision, thereby being conducive to the perturbation modulation of the DAC.

[0103] In the optional embodiment, the input code word of the DAC and the analog unit state in the DAC are one-to-one corresponding, so as to be one-to-one corresponding with the mismatch error of the analog unit. The code word perturbation in the target perturbation modulation signal d realizes the perturbation of the mismatch error, reduces the possibility of quasi-periodic appearance of the mismatch error at the output end of the DAC, and further reduces the spur power and improves the SFDR performance. When the target perturbation modulation signal is directly transmitted to the DAC, the input code word of the DAC is the target perturbation modulation signal. When the target perturbation modulation signal is processed by other processing modules and then transmitted to the DAC, the input code word of the DAC is the output signal of the other processing modules.

[0104] It can be seen that the optional embodiment can realize real-time acquisition of the feedback signal by performing the weighting operation on the real-time disturbance modulation signal and the impulse response signal, is conducive to improving the acquisition accuracy of the target signal, and further improves the generation accuracy and reliability of the disturbance modulation signal for modulating the DAC, and further improves the SFDR performance of the DAC to ensure the stray radiation of the DAC.

[0105] The principles of the present scheme are illustrated below Figure 6 and Figure 7 The principles of the present scheme are illustrated below

[0106] Please refer to Figure 6 , a high-precision modulation signal a represented by x bits enters the subtracter in the form of a data stream, and the feedback data stream e output by the weighting filter also enters the subtracter. The subtracter is responsible for calculating the difference between a and e and outputting the difference data stream (target signal) b, and transmitting the difference data stream b to the loop filter for integral filtering processing to obtain the integral data stream (integral signal) c. The loop filter can select a first-order filter, a second-order filter, or even a high-order filter. The integral data stream c is quantized into a disturbance modulation signal d with a width of y (1≤y≤x) bits in the random quantizer (quantizer). The disturbance modulation signal d is sent as an output signal to the DAC, and the other enters the weighting filter for weighting filtering processing to obtain the feedback data stream e. The weighting filter can be implemented using an FIR or IIR filter.

[0107] Please refer to Figure 7 , Figure 7 is a schematic diagram of the principle of the random quantizer. After the integral data stream c enters the random quantizer, it first undergoes bidirectional quantization processing by the bidirectional quantizer to obtain quantized data streams f and g (first and second quantized signals). A pseudo-random sequence generator generates a binary random sequence h as a selection control signal for the selector module and a multi-bit random number sequence j as a disturbance signal for the bidirectional quantizer according to the pseudo-random number generation algorithm principle. The pseudo-random number generation algorithm principle includes but is not limited to linear feedback shift register method, mersenne rotation algorithm, congruence algorithm, and other algorithms that can generate multi-bit random numbers. The control signal h and the disturbance signal j are shaped to the required bit width and then output. The selector selects one of f and g as the output under the control of the control signal h, as the disturbance modulation signal of the DAC and the real-time disturbance signal of the weighting filter.

[0108] Embodiment two

[0109] Please refer to Figure 2 , Figure 2is a flow diagram of another quantization perturbation method based on a Sigma-Delta modulated DAC disclosed by the embodiment of the present application. Wherein, the quantization perturbation method based on a Sigma-Delta modulated DAC is applied to a quantization perturbation system, as shown in Figure 2 The quantization perturbation method based on a Sigma-Delta modulated DAC can include the following operations:

[0110] 201, calculate the difference between the determined modulation signal and the determined feedback signal as a target signal.

[0111] 202, perform a preprocessing operation on the target signal to obtain an integral signal, and the preprocessing includes integral processing.

[0112] 203, determine whether the integral signal meets the determined data analysis condition; when it is determined that the data analysis condition is met, step 204 is triggered; when it is determined that the data analysis condition is not met, step 205 is triggered.

[0113] 204, perform a quantization operation on the integral signal to obtain a target perturbation modulation signal, and the target perturbation modulation signal is used as a perturbation modulation signal of the DAC.

[0114] In the embodiment of the present application, it should be noted that after performing integral processing on the target signal to obtain the integral signal, there is no need to judge the data analysis condition of the integral signal, that is, there is no need to perform the operation of judging whether the integral signal meets the determined data analysis condition, and directly performing filtering processing on the integral signal. This is conducive to improving the processing efficiency of the integral signal, thereby improving the acquisition efficiency of the perturbation modulation signal.

[0115] In the embodiment of the present application, the width of the bit of the target perturbation modulation signal is less than or equal to the width of the bit of the modulation signal, and the width of the bit of the target perturbation modulation signal is greater than or equal to 1.

[0116] 205, perform filtering processing on the integral signal to obtain an integral signal that meets the data analysis condition.

[0117] 206, perform a quantization operation on the integral signal that meets the data analysis condition to obtain a target perturbation modulation signal, and the target perturbation modulation signal is used as a perturbation modulation signal of the DAC.

[0118] In the embodiment of the present application, the related description of steps 201, 202 and 204 is referred to the detailed description of steps 101-103 in the first embodiment, and the embodiment of the present application will not be repeated.

[0119] It can be seen that after the integral signal is determined, whether the integral signal meets the data analysis condition is further judged, if yes, subsequent quantization operation is executed, if not, filtering processing is executed on the integral signal, the integral signal meeting the data analysis condition can be obtained, so that the generation accuracy and reliability of the disturbance modulation signal of the DAC are further improved, and the SFDR performance of the DAC is further improved, so as to ensure the stray radiation of the DAC.

[0120] It can be seen that the embodiment Figure 2 The described quantization disturbance method based on the Sigma-Delta modulation DAC can obtain accurate disturbance modulation signals for disturbing the DAC by executing integral processing on the calculated signal and executing quantization operation on the signal after the integral processing, and the randomness of the quantization code word of the disturbance modulation signal is enhanced, the SFDR performance of the DAC is improved, so as to ensure the stray radiation of the DAC, and the DAC is not dependent on the specific implementation structure, has higher universality, can be used with DEM at the same time, and does not need to estimate the error of the DAC, that is, does not need to construct a complex DAC circuit, which is beneficial to reducing the control complexity of the DAC, and the integral signal meeting the data analysis condition can be obtained, so that the generation accuracy and reliability of the disturbance modulation signal of the DAC are further improved, and the SFDR performance of the DAC is further improved, so as to ensure the stray radiation of the DAC.

[0121] Embodiment three

[0122] Please refer to Figure 3 , Figure 3 is a structure schematic diagram of a quantization disturbance device based on a Sigma-Delta modulation DAC disclosed by the embodiment of the application. The quantization disturbance device based on the Sigma-Delta modulation DAC is applied to a quantization disturbance system. As shown in the figure, Figure 3 The quantization disturbance device based on the Sigma-Delta modulation DAC can include a subtracter 301, a quantizer 303, and a loop filter 302, and the output end of the device is electrically connected with the input end of a data processor including a DAC, wherein:

[0123] The subtracter 301 is used to calculate the difference between the determined modulation signal and the determined feedback signal as a target signal, and transmit the target signal to the loop filter.

[0124] The loop filter 302 is used to receive the target signal from the subtracter, execute pre-processing operation on the target signal to obtain an integral signal, and transmit the integral signal to the quantizer, and the pre-processing includes integral processing.

[0125] The quantizer 303 is configured to receive the integrated signal from the loop filter, and perform quantization on the integrated signal to obtain a target dithering modulation signal, which is used as a dithering modulation signal of the DAC, wherein the width of the bit of the dithering modulation signal is less than or equal to the width of the bit of the modulation signal and greater than or equal to 1.

[0126] In the embodiment of the present application, the output of the device is not necessarily electrically connected to the input of the DAC, that is, the output of the device can be connected to the output of the DAC through other processing modules (also referred to as pre-stage modules of the DAC), wherein the other processing modules can include a digital shaping filter and the like, at this time, the data processor includes the other processing modules and the DAC, and the quantization dithering device, the other processing modules and the DAC are connected in sequence.

[0127] In the embodiment of the present application, the number of the Sigma-Delta modulation based DAC quantization dithering devices is greater than or equal to 1, that is, a plurality of Sigma-Delta modulation based DAC quantization dithering devices are connected in series through cascading, and the output of the last Sigma-Delta modulation based DAC quantization dithering device is electrically connected to the input of the digital processor.

[0128] It can be seen that the implementation Figure 3 The described Sigma-Delta modulation based DAC quantization dithering device can obtain an accurate dithering modulation signal for dithering the DAC by performing integration on the calculated signal and performing quantization on the integrated signal, and can enhance the randomness of the quantization code word of the dithering modulation signal, improve the SFDR performance of the DAC, ensure the spurious radiation of the DAC, and does not depend on the specific implementation structure of the DAC, has higher universality, can be used with the DEM at the same time, and does not need to estimate the error of the DAC, that is, does not need to construct a complex DAC circuit, which is beneficial to reduce the control complexity of the DAC.

[0129] In an optional embodiment, as shown in Figure 4 The quantizer 303 includes a bidirectional quantizer 3031 and a selector 3032.

[0130] The bidirectional quantizer 3031 is configured to perform bidirectional quantization on the integrated signal and the obtained dithering signal to obtain a first quantization signal and a second quantization signal, and transmit the first quantization signal and the second quantization signal to the selector 3032.

[0131] The selector 3032 is configured to receive the first quantization signal and the second quantization signal sent by the bidirectional quantizer 3031, and determine a target quantization signal as a target dithering modulation signal based on an obtained control signal, the target quantization signal being the first quantization signal or the second quantization signal, the dithering signal and the control signal being random sequences of different bases.

[0132] It can be seen that, in the implementation Figure 4 The Sigma-Delta modulation DAC-based quantization dithering device described herein can obtain two quantization signals based on a dithering signal, and select one of the quantization signals under the control of a control signal, thereby achieving the obtaining of a dithering modulation signal for dithering a DAC, improving the obtaining accuracy and reliability of the dithering modulation signal, thereby obtaining a random quantization dithering signal, further reducing the quasi-periodic probability of a signal appearing in the DAC, and further improving the SFDR performance of the DAC to further ensure the spurious radiation of the DAC.

[0133] In another optional embodiment, as Figure 4 shown, the quantizer 303 further includes a pseudo-random sequence generator 3033, wherein:

[0134] The pseudo-random sequence generator 3033 is configured to generate a target dithering signal and a target control signal, transmit the target dithering signal to the bidirectional quantizer 3031, and transmit the target control signal to the selector 3032.

[0135] The bidirectional quantizer 3031 is further configured to receive the target dithering signal sent by the pseudo-random sequence generator 3033 as an obtained dithering signal, and trigger the operation of performing the bidirectional quantization on the integral signal and the obtained dithering signal to obtain the first quantization signal and the second quantization signal.

[0136] The selector 3032 is further configured to receive the target control signal sent by the pseudo-random sequence generator 3033 as an obtained control signal, and trigger the operation of determining a target quantization signal as a target dithering modulation signal based on the obtained control signal.

[0137] It can be seen that, in the implementation Figure 4 The Sigma-Delta modulation DAC-based quantization dithering device described herein can generate real-time control signals and dithering signals that match the current state of the DAC through the pseudo-random sequence generator, which is conducive to improving the efficiency and accuracy of obtaining quantization signals, thereby improving the generation accuracy and reliability of the dithering modulation signal for modulating the DAC, and further improving the SFDR performance of the DAC to ensure the spurious radiation of the DAC.

[0138] In yet another optional embodiment, as Figure 4As shown, the apparatus further comprises a weighting filter 304, wherein:

[0139] The weighting filter 304 is configured to acquire the real-time disturbance modulation signal, and perform a weighting operation on the acquired real-time disturbance modulation signal and the acquired impulse response signal to obtain a weighted signal, and transmit the weighted signal to the subtracter 301.

[0140] The subtracter 301 is further configured to receive the weighted signal transmitted by the weighting filter 304 as the determined feedback signal, and trigger the operation of calculating the difference between the determined modulation signal and the determined feedback signal as the target signal.

[0141] It can be seen that, in the implementation Figure 4 The Sigma-Delta modulation DAC-based quantization disturbance apparatus described above can realize real-time acquisition of the feedback signal by performing a weighting operation on the real-time disturbance modulation signal and the impulse response signal, which is beneficial to improve the acquisition accuracy of the target signal, and further improve the generation accuracy and reliability of the disturbance modulation signal for the DAC, and further improve the SFDR performance of the DAC to ensure the spurious radiation of the DAC.

[0142] In yet another optional embodiment, as Figure 4 As shown, the loop filter 302 is further configured to, after performing the preprocessing operation on the target signal to obtain the integral signal, judge whether the integral signal satisfies the determined data analysis condition; when it is judged that the data analysis condition is satisfied, transmit the integral signal to the quantizer 303 to trigger the quantizer to perform the operation of receiving the integral signal from the loop filter 302 and performing a quantization operation on the integral signal to obtain the target disturbance modulation signal, which is used as the DAC disturbance modulation signal; when it is judged that the data analysis condition is not satisfied, perform a filtering process on the integral signal to obtain an integral signal satisfying the data analysis condition, and transmit the integral signal satisfying the data analysis condition to the quantizer 303.

[0143] The quantizer 303 is further configured to receive the integral signal satisfying the data analysis condition transmitted by the loop filter 302, and perform a quantization operation on the integral signal satisfying the data analysis condition to obtain the target disturbance modulation signal, which is used as the DAC disturbance modulation signal.

[0144] It can be seen that, in the implementation Figure 4The described Sigma-Delta modulation-based DAC quantization disturbance device can further determine whether the integral signal meets the data analysis condition after determining the integral signal, and if so, perform subsequent quantization operation, and if not, perform filtering processing on the integral signal, so as to obtain the integral signal meeting the data analysis condition, thereby further improving the generation accuracy and reliability of the disturbance modulation signal of the DAC, and further improving the SFDR performance of the DAC to ensure the stray radiation of the DAC.

[0145] Embodiment four

[0146] Please refer to Figure 5 , Figure 5 The described Sigma-Delta modulation-based DAC quantization disturbance device can further determine whether the integral signal meets the data analysis condition after determining the integral signal, and if so, perform subsequent quantization operation, and if not, perform filtering processing on the integral signal, so as to obtain the integral signal meeting the data analysis condition, thereby further improving the generation accuracy and reliability of the disturbance modulation signal of the DAC, and further improving the SFDR performance of the DAC to ensure the stray radiation of the DAC. Figure 5 The Sigma-Delta modulation-based DAC quantization disturbance device can include:

[0147] The memory 501 stores executable program codes;

[0148] The processor 502 is coupled to the memory 501;

[0149] Further, the input interface 503 and the output interface 504 coupled to the processor 502 can be further included;

[0150] The processor 502 calls the executable program codes stored in the memory 501, and is used to execute the steps of the Sigma-Delta modulation-based DAC quantization disturbance method described in the embodiment one or the embodiment two.

[0151] Embodiment five

[0152] The computer readable storage medium stores a computer program for electronic data exchange, and the computer program makes the computer execute the steps of the Sigma-Delta modulation-based DAC quantization disturbance method described in the embodiment one or the embodiment two.

[0153] Embodiment six

[0154] The computer program product includes a non-transitory computer readable storage medium storing a computer program, and the computer program is operable to make the computer execute the steps of the Sigma-Delta modulation-based DAC quantization disturbance method described in the embodiment one or the embodiment two.

[0155] The apparatus embodiments described above are only illustrative, wherein the modules described as separate components can or can not be physically separated, and the components displayed as modules can or can not be physical modules, i.e., can be located in one place or distributed on multiple network modules. Part or all of the modules can be selected to achieve the purposes of the embodiments according to actual needs. Those skilled in the art can understand and implement without creative labor.

[0156] Through the specific description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be realized by means of software and necessary general hardware platform, and of course can also be realized by hardware. Based on such understanding, the above technical solutions can be embodied in the form of software products, and the computer software products can be stored in a computer readable storage medium, including Read-Only Memory (ROM), Random Access Memory (RAM), Programmable Read-Only Memory (PROM), Erasable Programmable Read-Only Memory (EPROM), One-time Programmable Read-Only Memory (OTPROM), Electrically-Erasable Programmable Read-Only Memory (EEPROM), Compact Disc Read-Only Memory (CD-ROM) or other optical disk storage, magnetic disk storage, magnetic tape storage, or any other computer readable medium capable of carrying or storing data.

[0157] Finally, it should be noted that: the quantization disturbance method and device based on Sigma-Delta modulation DAC disclosed by the embodiments of the present application are only the preferred embodiments of the present application, and are used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that; the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not make the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A quantization perturbation method based on a Sigma-Delta modulated DAC, characterized in that, The method includes: The difference between the determined modulation signal and the determined feedback signal is calculated and used as the target signal. Preprocessing is then performed on the target signal to obtain the integral signal, wherein the preprocessing includes integration processing. The integral signal is quantized to obtain a target perturbation modulation signal, which is used as the perturbation modulation signal of the DAC. Wherein, the width of the bit of the target perturbation modulation signal is less than or equal to the width of the bit of the modulation signal and the width of the bit of the target perturbation modulation signal is greater than or equal to 1; The step of performing a quantization operation on the integral signal to obtain the target perturbation modulation signal includes: A bidirectional quantization operation is performed on the integral signal and the acquired perturbation signal to obtain a first quantized signal and a second quantized signal; The target quantization signal is determined based on the acquired control signal and used as the target perturbation modulation signal. The target quantization signal is either the first quantization signal or the second quantization signal. The perturbation signal and the control signal are random sequences of different bases. Specifically, a selection flag bit for the quantization signal is set in advance for the control signal. Different quantization signals correspond to different selection flag bits, and an association relationship between different selection flag bits and corresponding quantization signals is established in advance. The association relationship corresponding to each quantization signal is used as the basis for the control signal to determine the target quantization signal.

2. The quantization perturbation method based on a Sigma-Delta modulated DAC according to claim 1, characterized in that, The method further includes: Generate a target disturbance signal and a target control signal, and determine that the target disturbance signal is the acquired disturbance signal and the target control signal is the acquired control signal, and trigger the execution of the bidirectional quantization operation on the integral signal and the acquired disturbance signal to obtain a first quantized signal and a second quantized signal.

3. The quantization perturbation method based on a Sigma-Delta modulated DAC according to claim 1 or 2, characterized in that, The method further includes: The system acquires a real-time perturbation modulation signal and performs a weighting operation on the acquired real-time perturbation modulation signal and the acquired impulse response signal to obtain a weighted signal. The weighted signal is then determined as the feedback signal, and the system triggers the operation of calculating the difference between the determined modulation signal and the determined feedback signal as the target signal.

4. The quantization perturbation method based on a Sigma-Delta modulated DAC according to claim 1 or 2, characterized in that, After performing preprocessing on the target signal to obtain an integrated signal, and after performing quantization on the integrated signal to obtain a target perturbation modulation signal, before the target perturbation modulation signal is used as the perturbation modulation signal of the DAC, the method further includes: Determine whether the integral signal satisfies the determined data analysis conditions; When it is determined that the data analysis conditions are met, the quantization operation on the integral signal is triggered to obtain the target perturbation modulation signal, which is used as the perturbation modulation signal of the DAC. When it is determined that the data analysis conditions are not met, the integral signal is filtered to obtain the integral signal that meets the data analysis conditions. The step of performing a quantization operation on the integral signal to obtain a target perturbation modulation signal, the operation of using the target perturbation modulation signal as the perturbation modulation signal of the DAC, includes: A quantization operation is performed on the integral signal that meets the data analysis conditions to obtain the perturbation modulation signal of the DAC.

5. A quantization perturbation device based on a Sigma-Delta modulation DAC, characterized in that, The device includes a subtractor, a quantizer, and a loop filter, and its output is electrically connected to the input of a data processor, which includes the DAC. The subtractor is used to calculate the difference between the determined modulation signal and the determined feedback signal, which is then used as the target signal and transmitted to the loop filter. The loop filter is configured to receive the target signal from the subtractor, perform preprocessing on the target signal to obtain an integral signal, and transmit the integral signal to the quantizer, wherein the preprocessing includes integration processing. The quantizer is used to receive the integral signal from the loop filter and perform a quantization operation on the integral signal to obtain a target perturbation modulation signal. The target perturbation modulation signal is used as the perturbation modulation signal of the DAC. The bit width of the target perturbation modulation signal is less than or equal to the bit width of the modulation signal and the bit width of the target perturbation modulation signal is greater than or equal to 1. The quantizer includes a bidirectional quantizer and a selector, wherein: The bidirectional quantizer is used to perform bidirectional quantization operation on the integral signal and the acquired perturbation signal to obtain a first quantized signal and a second quantized signal, and to transmit the first quantized signal and the second quantized signal to the selector; The selector is used to receive the first quantized signal and the second quantized signal sent by the bidirectional quantizer, and determine the target quantized signal based on the acquired control signal as the target perturbation modulation signal. The target quantized signal is either the first quantized signal or the second quantized signal, and the perturbation signal and the control signal are random sequences of different bases. Specifically, a selection flag bit for the quantization signal is set in advance for the control signal. Different quantization signals correspond to different selection flag bits, and an association relationship between different selection flag bits and corresponding quantization signals is established in advance. The association relationship corresponding to each quantization signal is used as the basis for the control signal to determine the target quantization signal.

6. The quantization perturbation device based on a Sigma-Delta modulation DAC according to claim 5, characterized in that, The quantizer further includes a pseudo-random sequence generator, wherein: The pseudo-random sequence generator is used to generate a target perturbation signal and a target control signal, and to transmit the target perturbation signal to the bidirectional quantizer and the target control signal to the selector; The bidirectional quantizer is also used to receive the target perturbation signal sent by the pseudo-random sequence generator as the acquired perturbation signal, and to trigger the execution of the bidirectional quantization operation on the integral signal and the acquired perturbation signal to obtain the first quantized signal and the second quantized signal. The selector is also used to receive the target control signal sent by the pseudo-random sequence generator as the acquired control signal, and to trigger the operation of determining the target quantization signal based on the acquired control signal as the target perturbation modulation signal.

7. The quantization perturbation device based on a Sigma-Delta modulation DAC according to claim 5 or 6, characterized in that, The device further includes a weighted filter, wherein: The weighting filter is used to acquire the real-time perturbation modulation signal, and to perform a weighting operation on the acquired real-time perturbation modulation signal and the acquired impulse response signal to obtain a weighted signal, and to transmit the weighted signal to the subtractor. The subtractor is also used to receive the weighted signal sent by the weighted filter as a determined feedback signal, and trigger the operation of calculating the difference between the determined modulation signal and the determined feedback signal as the target signal.

8. The quantization perturbation device based on a Sigma-Delta modulation DAC according to claim 5 or 6, characterized in that, The loop filter is further configured to, after performing preprocessing on the target signal to obtain an integrated signal, determine whether the integrated signal meets the determined data analysis conditions; when it is determined that the data analysis conditions are met, transmit the integrated signal to the quantizer to trigger the quantizer to receive the integrated signal from the loop filter and perform quantization on the integrated signal to obtain a target perturbation modulation signal, which is used as the DAC perturbation modulation signal. When it is determined that the data analysis conditions are not met, the integral signal is filtered and the integral signal that meets the data analysis conditions is transmitted to the quantizer. The quantizer is further configured to receive the integral signal that satisfies the data analysis conditions sent by the loop filter, and perform a quantization operation on the integral signal that satisfies the data analysis conditions to obtain a target perturbation modulation signal, which is used as the DAC perturbation modulation signal.

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