A PAPR inhibition method, a reduction method, an inhibition system, and a reduction system.

Abstract

This invention discloses a PAPR suppression method, a restoration method, a suppression system, and a restoration system in the fields of coherent optical communication and orthogonal frequency division multiplexing (OFDM). The method includes: performing serial-to-parallel conversion on the bit data to be transmitted to obtain parallel data; performing three-dimensional mapping on the parallel data using a preset constellation diagram to obtain a three-dimensional frequency domain signal; performing a two-dimensional inverse Fourier transform on the three-dimensional frequency domain signal to obtain a three-dimensional time domain signal; expanding the three-dimensional time domain signal using a three-dimensional constellation diagram to obtain a time domain signal with decreasing PAPR; adding a cyclic prefix to the time domain signal with decreasing PAPR to obtain a time domain signal with added cyclic prefix; and performing parallel-to-serial conversion on the time domain signal with added cyclic prefix to obtain a transmittable time domain signal.

Description

Technical Field

[0001] This invention relates to the fields of coherent optical communication and orthogonal frequency division multiplexing (OFDM) technology, and particularly to a PAPR suppression method, a restoration method, a suppression system, and a restoration system. Background Technology

[0002] Orthogonal Frequency Division Multiplexing (OFDM) is a core physical layer technology for systems such as 4G / 5G and Wi-Fi, but its inherent peak-to-average power ratio (PAPR) problem severely restricts system performance. A high PAPR forces power amplifiers to operate outside the linear region, leading to decreased efficiency, signal distortion, and out-of-band radiation.

[0003] Existing PAPR suppression techniques are mainly classified into distortion-based, probabilistic, and coding methods. Distortion-based techniques (such as clipping and companding) are simple and effective, but they introduce signal distortion, leading to increased bit error rate and out-of-band interference. Probabilistic techniques, such as Partial Transmission Sequence (PTS) and Selective Mapping (SLM), can avoid signal distortion, but they have high computational complexity and require the transmission of additional sideband information, reducing spectral efficiency. Coding techniques, while avoiding distortion and sideband information issues, have a limited number of available codebooks, limiting the gain and practicality of PAPR suppression.

[0004] Furthermore, the aforementioned methods are all based on the traditional two-dimensional constellation mapping and one-dimensional IFFT OFDM framework, which faces inherent bottlenecks in performance optimization. The 3D-OFDM technology (based on three-dimensional signal mapping and two-dimensional IFFT) that has emerged in recent years has shown potential in bit error rate performance, but current research is not in-depth, especially lacking mature solutions that effectively combine traditional PAPR suppression techniques with the 3D-OFDM framework, resulting in its performance advantages not being fully realized. Therefore, existing technologies still have significant limitations, and better solutions are urgently needed. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a PAPR suppression method, a reduction method, a suppression system, and a reduction system that achieve synergistic improvement in PAPR suppression and noise immunity without the need for additional sideband information, thereby enhancing the transmission performance of long-distance coherent optical communication systems.

[0006] To solve the above-mentioned technical problems, the present invention is implemented using the following technical solution:

[0007] In a first aspect, the present invention provides a PAPR suppression method, comprising:

[0008] The bit data to be transmitted is converted from serial to parallel to obtain parallel data;

[0009] The parallel data is three-dimensionally mapped using a preset constellation diagram to obtain a three-dimensional frequency domain signal;

[0010] Perform a two-dimensional inverse Fourier transform on the three-dimensional frequency domain signal to obtain a three-dimensional time domain signal;

[0011] The three-dimensional time-domain signal is extended with a three-dimensional constellation diagram to obtain a time-domain signal with decreasing PAPR.

[0012] A cyclic prefix is ​​added to the time-domain signal with the decreased PAPR to obtain a time-domain signal with the added cyclic prefix;

[0013] The time-domain signal with the added cyclic prefix is ​​converted from parallel to serial to obtain a transmittable time-domain signal.

[0014] Optionally, the expression for the three-dimensional frequency domain signal is as follows:

[0015] S freq = [ S 0 freq , S 1 freq , … , S C − 1 freq ] = [ S x , 0 freq S x , 1 freq S x , 2 freq … S x , C − 1 freq S y , 0 freq S y , 1 freq S y , 2 freq … S y , C − 1 freq S z , 0 freq S z , 1 freq S z , 2 freq … S z , C − 1 freq ] ,

[0016] in, Represents a three-dimensional frequency domain signal. Indicates the number of subcarriers. Indicates the first subcarrier. Indicates the second subcarrier. This represents the Cth subcarrier. express The components on the x-axis, express Components on the y-axis express The components on the z-axis, express The components on the x-axis, express Components on the y-axis express The components on the z-axis, express The components on the x-axis, express Components on the y-axis express The components on the z-axis, express The components on the x-axis, express Components on the y-axis express The component on the z-axis.

[0017] Optionally, the expression for the three-dimensional time-domain signal is as follows:

[0018] ,

[0019] in, Representing three-dimensional time-domain signals The Middle Line number The element at the column position, represents an imaginary number, Indicates the number of subcarriers. Represents the third in the three-dimensional frequency domain signal Line number The element at the column position, Represents the natural base. It represents pi (π).

[0020] Optionally, the three-dimensional constellation diagram extension of the three-dimensional time-domain signal includes:

[0021] Repeat the following steps until the time-domain signal of PAPR decreases meets the PAPR requirement or the maximum number of iterations is reached:

[0022] For the three-dimensional time domain signal Amplification is performed to obtain the three-dimensional time-domain signal after amplification. ;

[0023] Calculate the three-dimensional time-domain signal after amplitude limiting With three-dimensional time domain signals The difference ;

[0024] For the difference Perform a two-dimensional Fourier transform to obtain the frequency domain signal. ;

[0025] According to the three-dimensional frequency domain signal and frequency domain signals Get the judgment set ;

[0026] According to the judgment set and three-dimensional frequency domain signals Calculate the frequency domain signal of PAPR descent ;

[0027] For frequency domain signals with decreasing PAPR Perform a two-dimensional inverse Fourier transform to obtain the time-domain signal of PAPR decrease.

[0028] Optionally, the clipped three-dimensional time-domain signal It can be obtained through the following formula:

[0029] S time ′ [ n ] = { S time [ n ] , | S time [ n ] | ≤ A ′ A ′ ⋅ e j θ [ n ] , | S time [ n ] | > A ′ ,

[0030] in, S time ′ [ n ] Represents the three-dimensional time-domain signal after clipping. The Middle Subcarriers, θ [ n ] Representing three-dimensional time-domain signals The Middle The phase of each subcarrier, Indicates the threshold value. represents an imaginary number;

[0031] The difference It can be obtained through the following formula:

[0032] c c l i p = S time ′ [ n ] − S time [ n ] ,

[0033] in, S time [ n ] Representing three-dimensional time-domain signals The Middle Subcarriers.

[0034] Optionally, the judgment set It can be obtained through the following formula:

[0035] C j u d g e = { C clip [ n ] , S freq [ n ] + C clip [ n ] ∈ R p ( A n → i ′ ) 0 , S freq [ n ] + C clip [ n ] ∉ R p ( A n → i ′ ) ,

[0036] in, express The expansion area Indicates the first Each subcarrier corresponds to a 3D constellation point in the preset constellation diagram. ;

[0037] The frequency domain signal of PAPR decrease It can be obtained through the following formula:

[0038] S freq ′ [ n ] = S freq [ n ] + C j u d g e [ n ] ,

[0039] in, S freq ′ [ n ] express The Middle Subcarriers, S freq [ n ] express The Middle Subcarriers, C j u d g e [ n ] express The Middle Subcarriers.

[0040] Optionally, the extended region is obtained by the following formula:

[0041] ,

[0042] in, This indicates the first constellation in the preset constellation diagram. A 3D constellation point, This indicates the first constellation in the preset constellation diagram. A 3D constellation point, express The expansion area express Candidate expansion areas This indicates the total number of 3D constellation points in the preset constellation map. Represents the set of real numbers. Represent any real number, express of Axial components, express of Axial components, express of Axial components, express of Axial components, express of Axial components, express of Axial components, express Any real number in the range.

[0043] Secondly, this invention provides a constellation diagram extended PAPR reconstruction method based on three-dimensional OFDM, comprising:

[0044] The received time-domain signal is converted from serial to parallel to obtain parallel data;

[0045] Remove the cycle prefix from the parallel data to obtain parallel data with the cycle prefix removed;

[0046] A two-dimensional Fourier transform is performed on the parallel data with the cyclic prefix removed to obtain a three-dimensional frequency domain signal;

[0047] The three-dimensional frequency domain signal is demapped using a preset constellation diagram to obtain demapped data;

[0048] The received data is obtained by performing parallel-to-serial conversion on the demapped data;

[0049] The received time-domain signal is obtained using the method described in any one of the first aspects.

[0050] Thirdly, the present invention provides a PAPR suppression system, comprising:

[0051] The first serial-to-parallel conversion module is used to: convert the bit data to be transmitted into serial-to-parallel data to obtain parallel data;

[0052] The constellation 3D mapping module is used to: perform 3D mapping on the parallel data using a preset constellation diagram to obtain a 3D frequency domain signal;

[0053] The two-dimensional inverse Fourier transform module is used to: perform a two-dimensional inverse Fourier transform on the three-dimensional frequency domain signal to obtain a three-dimensional time domain signal;

[0054] The three-dimensional constellation diagram extension module is used to: extend the three-dimensional time-domain signal into a three-dimensional constellation diagram to obtain a time-domain signal with decreasing PAPR;

[0055] The module for adding a cyclic prefix is ​​used to: add a cyclic prefix to the time-domain signal of the PAPR decrease, so as to obtain a time-domain signal with the cyclic prefix added;

[0056] The first parallel-to-serial conversion module is used to: perform parallel-to-serial conversion on the time-domain signal with added cyclic prefix to obtain a transmittable time-domain signal.

[0057] Fourthly, the present invention provides a PAPR restoration system, comprising:

[0058] The second serial-to-parallel conversion module is used to: convert the received time-domain signal into serial-to-parallel data;

[0059] The cycle prefix removal module is used to: remove the cycle prefix from the parallel data to obtain parallel data with the cycle prefix removed;

[0060] The two-dimensional Fourier transform module is used to: perform a two-dimensional Fourier transform on the parallel data after removing the cyclic prefix to obtain a three-dimensional frequency domain signal;

[0061] The constellation 3D demapping module is used to: perform 3D demapping on the 3D frequency domain signal using a preset constellation diagram to obtain demapping data;

[0062] The second parallel-to-serial conversion module is used to: convert the demapped data into parallel-to-serial data to obtain the received data;

[0063] The received time-domain signal is obtained using the method described in any one of the first aspects.

[0064] Compared with existing technologies, the beneficial effects achieved by this invention are as follows: The three-dimensional constellation diagram improves the minimum Euclidean distance, which is beneficial for reducing the bit error rate in decoding decisions. The three-dimensional constellation diagram reduces the transmit power of constellation points, improving the problem of average power increase caused by constellation diagram expansion. Constellation diagram expansion based on three-dimensional constellation diagram and two-dimensional IFFT provides a more diverse expansion range, further enhancing PAPR suppression performance, providing an additional PAPR gain of approximately 0.8 dB in ten iterations, and achieving superior transmission efficiency. Attached Figure Description

[0065] Figure 1 The flowcharts are of the PAPR suppression and reduction methods provided in the embodiments of the present invention.

[0066] Figure 2 A two-dimensional 16QAM constellation diagram provided according to an embodiment of the present invention;

[0067] Figure 3 This is an expanded constellation diagram based on a two-dimensional 16QAM constellation diagram provided in an embodiment of the present invention;

[0068] Figure 4 A three-dimensional 16QAM constellation diagram before regional expansion provided according to an embodiment of the present invention;

[0069] Figure 5 This is a three-dimensional 16QAM constellation map with expanded region provided according to an embodiment of the present invention;

[0070] Figure 6 This is a PAPR result diagram of a two-dimensional / three-dimensional signal after ten constellation diagram expansion iterations, provided according to an embodiment of the present invention. Detailed Implementation

[0071] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments and specific features in the embodiments are detailed descriptions of the technical solution of the present application, rather than limitations thereof. In the absence of conflict, the embodiments and technical features in the embodiments can be combined with each other.

[0072] It should be noted that the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0073] Example 1:

[0074] This invention discloses a PAPR suppression method, with reference to... Figure 1As shown, the specific steps include the following:

[0075] S1, perform serial-to-parallel conversion on the bit data to be transmitted to obtain parallel data;

[0076] S2, the parallel data is three-dimensionally mapped using a preset constellation diagram to obtain a three-dimensional frequency domain signal;

[0077] S3, perform a two-dimensional inverse Fourier transform on the three-dimensional frequency domain signal to obtain a three-dimensional time domain signal;

[0078] S4, perform a three-dimensional constellation diagram expansion on the three-dimensional time-domain signal to obtain a time-domain signal with decreasing PAPR;

[0079] S5, add a cyclic prefix to the time-domain signal of the PAPR decrease to obtain a time-domain signal with the cyclic prefix added;

[0080] S6, perform parallel-to-serial conversion on the time-domain signal with added cyclic prefix to obtain a transmittable time-domain signal.

[0081] In step S2, the preset constellation diagram is as follows: ,in, The modulation order, This indicates the first constellation in the preset constellation diagram. There are 10 constellation points, each representing a 3D coordinate vector. [ A i , x A i , y A i , z ] , , express of Axial components, express of Axial components, express of Axis components; the original bit data after serial-to-parallel conversion is uniquely mapped to the corresponding frequency domain signal through a predefined constellation diagram, resulting in the following three-dimensional frequency domain signal:

[0082] S freq = [ S 0 freq , S 1 freq , … , S C − 1 freq ] = [ S x , 0 freq S x , 1 freq S x , 2 freq … S x , C − 1 freq S y , 0 freq S y , 1 freq S y , 2 freq … S y , C − 1 freq S z , 0 freq S z , 1 freq S z , 2 freq … S z , C − 1 freq ] ,

[0083] in, Represents a three-dimensional frequency domain signal. Indicates the number of subcarriers. Indicates the first subcarrier. Indicates the second subcarrier. This represents the Cth subcarrier. express The components on the x-axis, express Components on the y-axis express The components on the z-axis, express The components on the x-axis, express Components on the y-axis express The components on the z-axis, express The components on the x-axis, express Components on the y-axis express The components on the z-axis, express The components on the x-axis, express Components on the y-axis express The component on the z-axis.

[0084] In step S2, the three-dimensional frequency domain signal needs to be converted using two-dimensional inverse Fourier transform (2D IFFT). Converted to three-dimensional time domain signal :

[0085] ,

[0086] in, Representing three-dimensional time-domain signals The Middle Line number The element at the column position, , represents an imaginary number, Indicates the number of subcarriers. Represents the third in the three-dimensional frequency domain signal Line number The element at the column position, Represents the natural base. It represents pi (π).

[0087] In step S4, the three-dimensional constellation diagram extension of the three-dimensional time-domain signal includes:

[0088] For the three-dimensional time domain signal Amplification is performed to obtain the three-dimensional time-domain signal after amplification. :

[0089] S time ′ [ n ] = { S time [ n ] , | S time [ n ] | ≤ A ′ A ′ ⋅ e j θ [ n ] , | S time [ n ] | > A ′ ,

[0090] in, S time ′ [ n ] Represents the three-dimensional time-domain signal after clipping. The Middle Subcarriers, θ [ n ] Representing three-dimensional time-domain signals The Middle The phase of each subcarrier, This indicates the amplitude limiting threshold, which limits amplitudes greater than a certain threshold. The time-domain signal amplitude is reduced to To reduce peak power, represents an imaginary number;

[0091] Calculate the three-dimensional time-domain signal after amplitude limiting With three-dimensional time domain signals The difference :

[0092] c c l i p = S time ′ [ n ] − S time [ n ] ,

[0093] in, S time [ n ] Representing three-dimensional time-domain signals The Middle Subcarriers;

[0094] For the difference Perform a two-dimensional Fourier transform to obtain the frequency domain signal. Because there are very few time-domain points that exceed the amplitude limit threshold, Most of the elements in the array are zero, for Instead Performing a two-dimensional FFT greatly simplifies the computational load;

[0095] According to the three-dimensional frequency domain signal and frequency domain signals Get the judgment set :

[0096] C j u d g e = { C clip [ n ] , S freq [ n ] + C clip [ n ] ∈ R p ( A n → i ′ ) 0 , S freq [ n ] + C clip [ n ] ∉ R p ( A n → i ′ ) ,

[0097] in, express The expansion area Indicates the first Each subcarrier corresponds to a 3D constellation point in the preset constellation diagram. If the frequency domain signal after clipping meets the extended region, the obtained frequency domain signal is retained; otherwise, the original signal is restored.

[0098] According to the judgment set and three-dimensional frequency domain signals Calculate the frequency domain signal of PAPR descent :

[0099] S freq ′ [ n ] = S freq [ n ] + C j u d g e [ n ] ,

[0100] in, S freq ′ [ n ] express The Middle Subcarriers, S freq [ n ] express The Middle Subcarriers, C j u d g e [ n ] express The Middle Subcarriers;

[0101] For frequency domain signals with decreasing PAPR Perform a two-dimensional inverse Fourier transform to obtain the time-domain signal of PAPR decrease;

[0102] Repeat the above steps until the time-domain signal of PAPR decreases meets the PAPR requirement or the maximum number of iterations is reached.

[0103] In this embodiment, for 3D constellation points ,in The extended region is represented as In obtaining Before that, you need to obtain Candidate expansion areas :

[0104] ,

[0105] in, This indicates the first constellation in the preset constellation diagram. A 3D constellation point, This indicates the total number of 3D constellation points in the preset constellation map. Represents the set of real numbers. Represent any real number, express of Axial components, express of Axial components, express of Axial components, express of Axial components, express of Axial components, express of Axis components. When this definition is not met, the extended point will be closer to other constellation points, which will lead to misjudgment during decoding and an increase in the bit error rate. It should be noted that the distance between the two points needs to be calculated in three dimensions, not in two dimensions as in the previous 2D constellation points.

[0106] A Voronoi element is closed when all its boundary segments are bounded, and the corresponding constellation points are called interior points. Conversely, a Voronoi element is open if some of its boundary segments are unbounded, and the corresponding constellation points are called exterior points. (See reference) Figure 2 As shown, taking the classic 16QAM as an example, the four innermost points are internal points, and the rest are external points.

[0107] Available expansion areas Then, obtain the following formula :

[0108] ,

[0109] in, express Any real number in the constellation; that is, a point in the constellation. Corresponding expansion area All constellation points in the chart need to meet the following conditions, except for... For any constellation point other than [the one mentioned above], the distance to that constellation point is greater than or equal to [the distance to the constellation point]. The distance to that constellation point. This extended area constraint is also to ensure that the expansion of the constellation point does not reduce the minimum Euclidean distance, thereby increasing the bit error rate; in addition, The definition of an internal constellation point prevents its expansion. This is because, regardless of the direction in which an internal constellation point expands, there will always be other constellation points whose distance from that internal point is greater than their distance to the corresponding expansion point. (Reference) Figure 3 The image shows a constellation diagram after 16QAM has been expanded. It can be seen that the four inner points cannot be further expanded due to the limitation of the expansion area; this limitation also applies to the expansion of 3D constellation diagrams. Figure 4 The image shown is a 3D 16QAM constellation diagram before the region expansion. Figure 5 The image shown is a three-dimensional 16QAM constellation diagram after the region expansion.

[0110] The extended region limitation proposed in this embodiment is fundamentally to prevent the constellation expansion from increasing the minimum Euclidean distance. Furthermore, constellation expansion inevitably leads to an increase in average power. Three-dimensional OFDM can reduce the average transmit power of constellation points compared to two-dimensional OFDM while maintaining a constant minimum Euclidean distance. Taking 16QAM as an example, a typical 16QAM... Figure 2As shown, the coordinates consist of 16 points formed by ±1 and ±3, with a minimum Euclidean distance of 2 and an average transmit power of 10 for the constellation points. The three-dimensional 16QAM is as follows: Figure 4 As shown, it consists of two cubes, an inner and an outer one. The x, y, and z coordinates of the eight vertices of the inner cube are defined by ±1, while the x, y, and z coordinates of the eight vertices of the outer cube are defined by ±(1+1). The constellation is composed of [8×3+] points, with a minimum Euclidean distance of 2. The average transmit power of the constellation points is [8×3+]. [×3] / 16 ≈ 8.47. Calculations show that 3D 16QAM provides approximately 15.3% reduction in transmit power at constellation points compared to 2D 16QAM. Therefore, constellation expansion based on 3D OFDM can significantly mitigate the drawbacks of increased power. Simultaneously, the reduced transmit power at the same MED also implies an increase in MED at the same transmit power, improving noise immunity and thus leading to a decrease in bit error rate.

[0111] Furthermore, the constellation diagram extension based on 3D OFDM also extends the extension region to 3D, providing a more diverse extension range. This allows more amplitude-limited signals to fall into the extension region in each iteration, reducing the PAPR obtained in each iteration.

[0112] The constellation graph extension technique used in this embodiment is similar to the distortion method in its implementation. After limiting the time-domain OFDM signal, an FFT is performed, retaining the extended constellation points and restoring the others. Then, an IFFT is performed, and the above steps are repeated until a preset maximum number of iterations or a PAPR requirement is reached. However, in principle, constellation graph extension is still a probabilistic method. It maps external constellation points to specific regions, causing changes in both the amplitude and phase of the transmitted signal. This avoids the high peak values ​​caused by the superposition of multiple subcarriers in phase, thus reducing PAPR. Compared to other probabilistic methods, constellation graph extension does not increase the bit error rate or introduce additional sideband information. However, because it extends the constellation points outward, it inevitably leads to an increase in average power.

[0113] This embodiment uses MATLAB for simulation, comparing the PAPR performance of constellation diagram extensions based on 2D OFDM and 3D OFDM in ten iterations, respectively. Figure 6 As shown. The simulation system uses 103 OFDM symbols, 512 subcarriers, and 16QAM modulation; to achieve a reasonable trade-off between computational cost and accuracy when approximating PAPR values, the oversampling rate is specified as L=4. The clipping threshold is set to twice the average power of the original signal; the complementary cumulative distribution function (CCDF) of PAPR is usually denoted as PAPR(x); the CCDF is defined as the probability that PAPR(x) exceeds a certain threshold y, i.e., CCDF(PAPR(x))=Pr(PAPR)>y).

[0114] Figure 6 The results show that, in the case of ten iterations, when Prob(PAPR(x)>y)=10⁻³, the constellation diagram extension based on 3D OFDM provides approximately 0.8 dB of PAPR gain compared to the constellation diagram extension based on 2D OFDM. Theoretical calculations and simulation results demonstrate that the constellation diagram extension based on 3D OFDM achieves a synergistic improvement in PAPR suppression and noise immunity.

[0115] In summary, the PAPR suppression method proposed in this embodiment obtains a three-dimensional frequency domain signal and a three-dimensional time domain signal through three-dimensional signal mapping and two-dimensional IFFT. After clipping the three-dimensional time domain signal, a two-dimensional FFT is performed again to obtain a clipped frequency domain matrix. The clipped frequency domain matrix is ​​then expanded into a three-dimensional constellation diagram using a three-dimensional expansion region decision. Clipped frequency domain signals within the expansion region are preserved, while clipped frequency domain signals outside the expansion region are restored to their original frequency domain signals. The signal after the three-dimensional constellation diagram expansion is then subjected to a two-dimensional IFFT to obtain a constellation diagram-expanded PAPR-suppressed time domain signal. If this time domain signal reaches the maximum number of iterations or the PAPR requirement, a parallel-to-serial conversion is performed, a cyclic prefix is ​​added, and the signal is transmitted through the channel. Otherwise, the three-dimensional constellation diagram expansion operation is repeated iteratively until the maximum number of iterations or the PAPR requirement is reached. This method achieves a synergistic improvement in PAPR suppression and noise immunity without requiring additional sideband information, thereby enhancing the transmission performance of long-distance coherent optical communication systems.

[0116] Example 2:

[0117] Based on the same inventive concept as Embodiment 1, this embodiment of the invention discloses a PAPR reduction method, with reference to... Figure 1 As shown, the specific steps include the following:

[0118] S1 performs serial-to-parallel conversion on the received time-domain signal to obtain parallel data;

[0119] S2, Remove the loop prefix from the parallel data to obtain parallel data with the loop prefix removed;

[0120] S3, perform a two-dimensional Fourier transform on the parallel data with the cyclic prefix removed to obtain a three-dimensional frequency domain signal;

[0121] S4, use a preset constellation diagram to perform three-dimensional demapping on the three-dimensional frequency domain signal to obtain demapping data;

[0122] S5, the demapped data is converted from parallel to serial to obtain the received data.

[0123] In step S1, the received time-domain signal is obtained using the method described in any one of Embodiment 1.

[0124] In step S3, the parallel data with the cyclic prefix removed is subjected to a two-dimensional Fourier transform to obtain a three-dimensional frequency domain signal, which is obtained through the following formula:

[0125] ,

[0126] in, Representing three-dimensional time-domain signals The Middle Line number The element at the column position, , represents an imaginary number, Indicates the number of subcarriers. Represents the third in the three-dimensional frequency domain signal Line number The element at the column position, Represents the natural base. It represents pi (π).

[0127] Example 3:

[0128] Based on the same inventive concept as Embodiment 1, this embodiment of the invention discloses a PAPR suppression system, comprising:

[0129] The first serial-to-parallel conversion module is used to: convert the bit data to be transmitted into serial-to-parallel data to obtain parallel data;

[0130] The constellation 3D mapping module is used to: perform 3D mapping on the parallel data using a preset constellation diagram to obtain a 3D frequency domain signal;

[0131] The two-dimensional inverse Fourier transform module is used to: perform a two-dimensional inverse Fourier transform on the three-dimensional frequency domain signal to obtain a three-dimensional time domain signal;

[0132] The three-dimensional constellation diagram extension module is used to: extend the three-dimensional time-domain signal into a three-dimensional constellation diagram to obtain a time-domain signal with decreasing PAPR;

[0133] The module for adding a cyclic prefix is ​​used to: add a cyclic prefix to the time-domain signal of the PAPR decrease, so as to obtain a time-domain signal with the cyclic prefix added;

[0134] The first parallel-to-serial conversion module is used to: perform parallel-to-serial conversion on the time-domain signal with added cyclic prefix to obtain a transmittable time-domain signal.

[0135] The specific functions of each module described above are explained in the relevant content of the method in Embodiment 1, and will not be repeated here.

[0136] Example 4:

[0137] Based on the same inventive concept as Embodiment 2, this embodiment of the invention discloses a PAPR restoration system, comprising:

[0138] The second serial-to-parallel conversion module is used to: convert the received time-domain signal into serial-to-parallel data;

[0139] The cycle prefix removal module is used to: remove the cycle prefix from the parallel data to obtain parallel data with the cycle prefix removed;

[0140] The two-dimensional Fourier transform module is used to: perform a two-dimensional Fourier transform on the parallel data after removing the cyclic prefix to obtain a three-dimensional frequency domain signal;

[0141] The constellation 3D demapping module is used to: perform 3D demapping on the 3D frequency domain signal using a preset constellation diagram to obtain demapping data;

[0142] The second parallel-to-serial conversion module is used to: convert the demapped data into parallel-to-serial data to obtain the received data;

[0143] The received time-domain signal is obtained using the method described in any one of Embodiment 1.

[0144] The specific functions of each module described above are explained in the relevant content of the method in Embodiment 2, and will not be repeated here.

[0145] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0146] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0147] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0148] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0149] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A PAPR suppression method, characterized by, The method comprises the following steps: serial-parallel conversion is performed on the bit data to be transmitted to obtain parallel data; the parallel data is mapped in three dimensions by using a preset constellation to obtain a three-dimensional frequency domain signal; inverse two-dimensional Fourier transform is performed on the three-dimensional frequency domain signal to obtain a three-dimensional time domain signal; three-dimensional constellation expansion is performed on the three-dimensional time domain signal to obtain a time domain signal with reduced PAPR; a cyclic prefix is added to the time domain signal with reduced PAPR to obtain a time domain signal with added cyclic prefix; parallel-serial conversion is performed on the time domain signal with added cyclic prefix to obtain a transmittable time domain signal; the expression of the three-dimensional frequency domain signal is as follows: ， wherein represents a three-dimensional frequency domain signal, represents a number of subcarriers, represents a first subcarrier, represents a second subcarrier, represents a Cth subcarrier, represents a component in the x-axis, represents a component in the y-axis, represents a component in the z-axis, represents a component in the x-axis, represents a component in the y-axis, represents a component in the z-axis, represents a component in the x-axis, represents a component in the y-axis, represents a component in the z-axis, represents a component in the x-axis, represents a component in the y-axis, represents a component in the z-axis; the three-dimensional constellation expansion on the three-dimensional time domain signal comprises the following steps: the following steps are repeatedly performed until the time domain signal with reduced PAPR meets the PAPR requirement or the maximum number of iterations is reached: clipping the three-dimensional time-domain signal to obtain a clipped three-dimensional time-domain signal ;​ computing the difference between the limited three-dimensional time domain signal and the three-dimensional time domain signal ;​ performing a two-dimensional Fourier transform on the difference to obtain a frequency domain signal ; According to the three-dimensional frequency domain signal and frequency domain signal acquiring a judgment set ; According to the judgment set and three-dimensional frequency domain signals computing PAPR-reduced frequency domain signals ; Frequency domain signal with PAPR reduction performing two-dimensional inverse Fourier transform to obtain a time domain signal with PAPR reduction; the limited three-dimensional time domain signal is obtained by the following equation: ， wherein denotes the amplitude limited three-dimensional time domain signal the phase of the subcarrier in the denotes the three-dimensional time domain signal the phase of the subcarrier in the denotes the amplitude threshold denotes the imaginary unit said difference is obtained by the equation: ， wherein represents a three-dimensional time domain signal in the th subcarrier; The judgment set By the following equation: ， wherein, represents an extended region of represents the first subcarrier in a preset constellation diagram ; The PAPR-reduced frequency-domain signal is obtained by the following equation: ， wherein represents the first subcarrier in the represents the first subcarrier in the represents the first subcarrier in the the expansion region is obtained by the following formula: ， in, This indicates the first constellation in the preset constellation diagram. A 3D constellation point, This indicates the first constellation in the preset constellation diagram. A 3D constellation point, express The expansion area express Candidate expansion areas This indicates the total number of 3D constellation points in the preset constellation map. Represents the set of real numbers. Represent any real number, express of Axial components, express of Axial components, express of Axial components, express of Axial components, express of Axial components, express of Axial components, express Any real number in the range.

2. The PAPR suppression method of claim 1, wherein, the expression of the three-dimensional time domain signal is as follows: ， wherein represents a three-dimensional time-domain signal represents an element of a matrix represents an element of a matrix represents an element of a matrix represents an imaginary number represents a number of subcarriers represents an element of a matrix represents an element of a matrix represents an element of a matrix represents a natural base number represents a number pi.

3. A method for constellation extension PAPR reduction based on three-dimensional OFDM, characterized in that, The method comprises the following steps: serial-parallel conversion is performed on the received time domain signal to obtain parallel data; the cyclic prefix in the parallel data is removed to obtain parallel data without cyclic prefix; two-dimensional Fourier transform is performed on the parallel data without cyclic prefix to obtain a three-dimensional frequency domain signal; three-dimensional demapping is performed on the three-dimensional frequency domain signal by using a preset constellation to obtain demapping data; the received data is obtained after parallel-serial conversion is performed on the demapping data; wherein the received time domain signal is obtained by the method in any one of claims 1 to 2.

4. A PAPR suppression system, characterized by, The method comprises the following steps: a first serial-parallel conversion module is configured to perform serial-parallel conversion on bit data to be transmitted to obtain parallel data; a constellation three-dimensional mapping module is configured to map the parallel data in three dimensions by using a preset constellation to obtain a three-dimensional frequency domain signal; a two-dimensional inverse Fourier transform module is configured to perform inverse two-dimensional Fourier transform on the three-dimensional frequency domain signal to obtain a three-dimensional time domain signal; a three-dimensional constellation expansion module is configured to perform three-dimensional constellation expansion on the three-dimensional time domain signal to obtain a time domain signal with reduced PAPR; an adding cyclic prefix module is configured to add a cyclic prefix to the time domain signal with reduced PAPR to obtain a time domain signal with added cyclic prefix; a first parallel-serial conversion module is configured to perform parallel-serial conversion on the time domain signal with added cyclic prefix to obtain a transmittable time domain signal; the expression of the three-dimensional frequency domain signal is as follows: ， wherein denotes a three-dimensional frequency domain signal, denotes a number of subcarriers, denotes a first subcarrier, denotes a second subcarrier, denotes a Cth subcarrier, denotes a component in the x-axis, denotes a component in the y-axis, denotes a component in the z-axis, denotes a component in the x-axis, denotes a component in the y-axis, denotes a component in the z-axis, denotes a component in the x-axis, denotes a component in the y-axis, denotes a component in the z-axis, denotes a component in the x-axis, denotes a component in the y-axis, denotes a component in the z-axis; the three-dimensional constellation expansion on the three-dimensional time domain signal comprises the following steps: the following steps are repeatedly performed until the time domain signal with reduced PAPR meets the PAPR requirement or the maximum number of iterations is reached: clipping the three-dimensional time-domain signal to obtain a clipped three-dimensional time-domain signal clipping the three-dimensional time-domain signal to obtain a clipped three-dimensional time-domain signal ; computing the difference between the limited three-dimensional time domain signal and the three-dimensional time domain signal ;​ performing a two-dimensional Fourier transform on the difference to obtain a frequency domain signal ; According to the three-dimensional frequency domain signal and frequency domain signal acquiring a judgment set ; According to the judgment set and three-dimensional frequency domain signals computing PAPR-reduced frequency domain signals ; Frequency domain signal with PAPR reduction performing two-dimensional inverse Fourier transform to obtain a time domain signal with PAPR reduction; the limited three-dimensional time domain signal is obtained by the following equation: ， wherein denotes the amplitude limited three-dimensional time domain signal denotes the phase of the th subcarrier in the denotes the three-dimensional time domain signal denotes the phase of the th subcarrier in the denotes the amplitude threshold value denotes the imaginary unit said difference is obtained by the equation: ， wherein represents a three-dimensional time domain signal in the middle of the subcarriers; The judgment set is obtained by the following equation: ， wherein, represents an extended region of represents the 3D constellation point corresponding to the first subcarrier in a preset constellation ; The PAPR-reduced frequency-domain signal is obtained by the following equation: ， wherein represents the first subcarrier in the OFDM symbol, represents the first subcarrier in the OFDM symbol, represents the first subcarrier in the OFDM symbol; the expansion region is obtained by the following formula: ， in, This indicates the first constellation in the preset constellation diagram. A 3D constellation point, This indicates the first constellation in the preset constellation diagram. A 3D constellation point, express The expansion area express Candidate expansion areas This indicates the total number of 3D constellation points in the preset constellation map. Represents the set of real numbers. Represent any real number, express of Axial components, express of Axial components, express of Axial components, express of Axial components, express of Axial components, express of Axial components, express Any real number in the range.

5. A three-dimensional OFDM constellation spreading PAPR reduction system, characterized by, The method comprises the following steps: a second serial-parallel conversion module is configured to perform serial-parallel conversion on a received time domain signal to obtain parallel data; a cyclic prefix removal module is configured to remove the cyclic prefix in the parallel data to obtain parallel data without cyclic prefix; a two-dimensional Fourier transform module is configured to perform two-dimensional Fourier transform on the parallel data without cyclic prefix to obtain a three-dimensional frequency domain signal; a constellation three-dimensional demapping module is configured to perform three-dimensional demapping on the three-dimensional frequency domain signal by using a preset constellation to obtain demapping data; a second parallel-to-serial conversion module, configured to perform parallel-to-serial conversion on the demapped data to obtain received data; wherein the received time domain signal is obtained by using the method in any one of claims 1 to 2.

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