QAM constellation diagram design method, modulator and computer storage medium

Abstract

The invention discloses a QAM (Quadrature Amplitude Modulation) constellation diagram design method, a modulator and a computer storage medium. The QAM constellation diagram design method comprises the steps that the symbol number M needed by QAM modulation and the bit number n of each symbol are obtained, and M = 2n; the 2n constellation points are distributed on the circumferences of a plurality of concentric circles with different radiuses in a two-dimensional plane, and the constellation point phases on the same concentric circle are uniformly distributed in a 360-degree plane; mapping codes of the constellation points in modulation are determined to obtain an optimal mapping code set, namely a complete constellation diagram, and the mapping codes are n-bit binary numbers. In this way, the PAPR of QAM high-order modulation can be reduced.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a Quadrature Amplitude Modulation (QAM) constellation design method, a modulator, and a computer storage medium. Background Art

[0002] Currently, high-order modulation schemes such as 16QAM and 64QAM are widely used in wired and wireless communication systems. Mapping multiple bits into a single symbol can achieve higher spectral efficiency to meet the growing demand for data transmission within limited bandwidth.

[0003] The existing 16QAM or 64QAM modulation method uses a rectangular constellation, where constellation points are evenly distributed in a 4*4 or 8*8 grid. The transmitter transmits the corresponding amplitude and phase according to the data to be transmitted.

[0004] During their long-term research and development, the inventors of this application discovered that these high-order modulation schemes present several key challenges, such as a high Peak-to-Average Power Ratio (PAPR). To ensure that the transmitter meets the required PAPR, the average power of the transmission system must be reduced. However, reducing the average power of the transmission system can affect transmission quality or increase transmitter complexity. Summary of the Invention

[0005] The main technical problem solved by this application is how to reduce the PAPR of QAM high-order modulation.

[0006] To solve the above technical problems, a technical solution adopted by this application is to provide a QAM constellation design method. The QAM constellation design method includes: obtaining the number of symbols M required for QAM modulation and the number of bits n of each symbol, where M=2 n ; 2 n The constellation points are distributed on the circumferences of multiple concentric circles with different radii in a two-dimensional plane, and the phases of the constellation points on the same concentric circle are evenly distributed within the 360° plane; the mapping codes of the constellation points in the modulation are determined to obtain the optimal mapping code set, that is, the complete constellation diagram, where the mapping code is an n-bit binary number.

[0007] Optionally, the radius R of the (m+1)th concentric circle m+1 =R m +d, where R m is the radius of the mth concentric circle, the radius of the first concentric circle is R1=1 / (2sin(π / (n+1))), and d is the minimum distance between two constellation points under a preset bit error rate.

[0008] Optionally, the constellation diagram includes 16 constellation points, and the 16 constellation points are distributed on the circumference of two concentric circles with different radii; wherein, 5 constellation points are distributed on the circumference of the first concentric circle of the constellation diagram, and 11 constellation points are distributed on the circumference of the second concentric circle of the constellation diagram; the radius R1 of the first concentric circle of the constellation diagram is 1 / (2*sin(π / 5)), and the radius R2 of the second concentric circle of the constellation diagram is 1 / (2*sin(π / 5)+d).

[0009] Optionally, the constellation diagram includes 64 constellation points, and the 64 constellation points are distributed on the circumference of 4 concentric circles with different radii; wherein, 7 constellation points are distributed on the circumference of the first concentric circle of the constellation diagram, 13 constellation points are distributed on the circumference of the second concentric circle of the constellation diagram, 19 constellation points are distributed on the circumference of the first concentric circle of the constellation diagram, and 25 constellation points are distributed on the circumference of the second concentric circle of the constellation diagram; the radius R1 of the first concentric circle of the constellation diagram is 1 / (2*sin(π / 7)), the radius R2 of the second concentric circle of the constellation diagram is 1 / (2*sin(π / 7))+d, the radius R3 of the third concentric circle of the constellation diagram is 1 / (2*sin(π / 7))+2*d, and the radius R4 of the fourth concentric circle of the constellation diagram is 1 / (2*sin(π / 7))+3*d.

[0010] Optionally, the radius R of the (m+1)th concentric circle m+1 =R m +d, where R m is the radius of the mth concentric circle, the radius of the first concentric circle is R1=1 / (2*sin(π / 4)), and d is the minimum distance between two constellation points under a preset bit error rate.

[0011] Optionally, the constellation diagram includes 256 constellation points, and the 256 constellation points are distributed on the circumferences of 9 concentric circles with different radii; wherein, 4 constellation points are distributed on the circumference of the first concentric circle of the constellation diagram, 10 constellation points are distributed on the circumference of the second concentric circle of the constellation diagram, 16 constellation points are distributed on the circumference of the third concentric circle of the constellation diagram, 23 constellation points are distributed on the circumference of the fourth concentric circle of the constellation diagram, 29 constellation points are distributed on the circumference of the fifth concentric circle of the constellation diagram, 35 constellation points are distributed on the circumference of the sixth concentric circle of the constellation diagram, 42 constellation points are distributed on the circumference of the seventh concentric circle of the constellation diagram, 48 constellation points are distributed on the circumference of the eighth concentric circle of the constellation diagram, and 49 constellation points are distributed on the circumference of the ninth concentric circle of the constellation diagram; the radius R1 of the first concentric circle of the constellation diagram = 1 / (2*sin(π / 4 )), the radius of the second concentric circle of the constellation diagram R2 = 1 / (2*sin(π / 4)) + d, the radius of the third concentric circle of the constellation diagram R3 = 1 / (2*sin(π / 4)) + 2*d, the radius of the fourth concentric circle of the constellation diagram R4 = 1 / (2*sin(π / 4)) + 3*d, the radius of the fifth concentric circle of the constellation diagram R5 = 1 / (2*sin(π / 4)) + 4*d, the radius of the sixth concentric circle of the constellation diagram R6 = 1 / (2*sin(π / 4)) + 5*d, the radius of the seventh concentric circle of the constellation diagram R7 = 1 / (2*sin(π / 4)) + 6*d, the radius of the eighth concentric circle of the constellation diagram R8 = 1 / (2*sin(π / 4)) + 7*d, and the radius of the ninth concentric circle of the constellation diagram R9 = 1 / (2*sin(π / 4)) + 8*d.

[0012] Optionally, the constellation diagram includes 1024 constellation points, and the 1024 constellation points are distributed on the circumferences of 18 concentric circles with different radii; wherein the numbers of constellation points distributed on the circumferences of the 18 concentric circles with different radii are 4, 10, 16, 23, 29, 35, 42, 48, 49, 54, 60, 67, 73, 79, 86, 92, 98, 104, and 104 respectively; and the radius of the first concentric circle to the radius of the eighteenth concentric circle are successively: R1=1 / (2*sin(π / 4)) , R2=1 / (2*sin(π / 4))+d, R3=1 / (2*sin(π / 4))+2*d, R4=1 / (2*sin(π / 4))+3*d, R5=1 / (2*sin(π / 4))+4*d, R 6=1 / (2*sin(π / 4))+5*d, R7=1 / (2*sin(π / 4))+6*d, R8=1 / (2*sin(π / 4))+7*d, R9=1 / (2*sin(π / 4))+8*d, R 10 =1 / (2*sin(π / 4))+9*d、R 11=1 / (2*sin(π / 4))+10*d、R 12 =1 / (2*sin(π / 4))+11*d、R 13 =1 / (2*sin(π / 4))+12*d、R 14 =1 / (2*sin(π / 4))+13*d、R 15 =1 / (2*sin(π / 4))+14*d、R 16 =1 / (2*sin(π / 4))+15*d、R 17 =1 / (2*sin(π / 4))+16*d、R 18 =1 / (2*sin(π / 4))+17*d.

[0013] Optionally, any three constellation points among the 2n constellation points are located on the curve.

[0014] To solve the above technical problems, another technical solution adopted by the present application is to provide a modulator. The modulator includes: an orthogonal signal generation module, configured to generate orthogonal I-channel and Q-channel signals from a bit stream obtained from a channel; a mapping module, coupled to the orthogonal signal generation module, configured to map the I-channel and Q-channel signals onto the above constellation diagram to obtain a QAM signal; and a memory, coupled to the mapping module, configured to store the above constellation diagram.

[0015] In order to solve the above technical problems, another technical solution adopted in this application is: providing a computer storage medium on which program instructions are stored, and when the program instructions are executed, the above QAM constellation diagram design method is implemented.

[0016] The beneficial effect of the present application is that, different from the prior art, the QAM constellation design method of the present application embodiment includes: obtaining the number of symbols M required for QAM modulation and the number of bits n of each symbol, where M=2 n ; 2 n The constellation points are distributed on the circumference of multiple concentric circles with different radii in a two-dimensional plane, and the phases of the constellation points on the same concentric circle are evenly distributed in the 360° plane; the mapping code of the constellation points in the modulation is determined to obtain the optimal mapping code set, that is, the complete constellation diagram, wherein the mapping code is an n-bit binary number. The QAM constellation diagram constructed by the QAM constellation diagram design method of the embodiment of the present application is 2 n The constellation points are distributed along the circumference of multiple concentric circles of different radii, and the phases of the constellation points on each circle are evenly distributed within a 360-degree plane. This overcomes the limitation on the number of constellation points per ring, allowing for a dense arrangement of constellation points, reducing redundant space on the circumference and lowering average power. Therefore, the QAM constellation diagram of this application can reduce the PAPR of QAM high-order modulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 It is a rectangular 16QAM constellation diagram;

[0019] Figure 2 It is a rectangular 64QAM constellation diagram;

[0020] Figure 3 This is a flow chart of an embodiment of the QAM constellation design method of the present application;

[0021] Figure 4 This application is 16QAM constellation Figure 1 A schematic structural diagram of an embodiment;

[0022] Figure 5 It is the 16APSK constellation diagram;

[0023] Figure 6 This application is 64QAM constellation Figure 1 A schematic structural diagram of an embodiment;

[0024] Figure 7 1 is a schematic structural diagram of an embodiment of a modulator of the present application;

[0025] Figure 8 It is a structural diagram of an embodiment of the computer storage medium of the present application. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0027] The terms "first" and "second" in this application are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically limited. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices.

[0028] The distribution diagram of the signal vector endpoints is called a constellation diagram. The existing constellation diagram of 16QAM (with 24 symbols) is as follows: Figure 1 As shown, the constellation diagram of 64QAM (with 26 symbols) is as follows Figure 2 shown.

[0029] This application first proposes a QAM constellation design method, such as Figure 3 As shown, Figure 3 This is a flow chart of an embodiment of the QAM constellation design method of the present application. The QAM constellation design method of this embodiment includes the following steps:

[0030] Step S101: Obtain the number of symbols M and the number of bits n per symbol required for QAM modulation, where M = 2 n .

[0031] QAM is essentially a combination of amplitude modulation and phase modulation, where the phase and amplitude states define a single number or combination of numbers. The advantage of QAM is a higher symbol rate, which results in higher system efficiency. The symbol rate typically determines the occupied bandwidth. Therefore, the more bits (basic information units) per symbol, the higher the efficiency.

[0032] For a given system, the number of symbols required is M = 2 n , n is the number of bits per symbol. For example, for 16QAM, n = 4, there are 16 symbols; for 64QAM, n = 6, there are 64 symbols.

[0033] Step S102: 2 n The constellation points are distributed on the circumferences of multiple concentric circles with different radii in a two-dimensional plane.

[0034] The constellation point allocation of this embodiment must meet the following principles: to suppress the peak-to-average ratio, the maximum distance from the constellation point to the center of the constellation diagram should be as small as possible and the arrangement of the constellation points should be as uniform as possible. Therefore, the constellation points are set on the circumference of concentric circles.

[0035] Step S103: Determine the mapping codes of the constellation points in the modulation to obtain an optimal mapping code set, that is, a complete constellation diagram, wherein the mapping codes are n-bit binary numbers.

[0036] For example, for 16QAM, n=4, so there are 16 symbols, each symbol represents 4 bits: 0000, 0001, 0010, etc. For 64QAM, n=6, so there are 64 symbols, each symbol represents 6 bits: 000000, 000001, 000010, etc.

[0037] Different from the prior art, the QAM constellation diagram constructed by the QAM constellation diagram design method of this embodiment is 2 n The constellation points are distributed on the circumference of multiple concentric circles of different radii, and the phases of the constellation points on each circle are evenly distributed within a 360-degree plane. This breaks the limitation on the number of constellation points on each circle, allowing the constellation points to be arranged tightly and reducing redundant space on the circumference. Therefore, it can reduce the PAPR of QAM high-order modulation.

[0038] Optionally, in this embodiment, the radius R of the (m+1)th concentric circle is m+1 =R m +d, where R m is the radius of the mth concentric circle, and the radius of the first concentric circle R1 = 1 / (2*sin(π / (n+1))). Where d is the minimum distance between two constellation points that achieves a certain bit error rate performance.

[0039] It can be seen that in this embodiment, the radius of the first concentric circle is the smallest, and the radius of the Ath concentric circle is the largest.

[0040] This embodiment optimizes the radius of each concentric circle to achieve better performance (further reducing the average power penalty). Therefore, the QAM constellation diagram of this application can achieve PAPR reduction at a lower average power penalty. The radius difference between two adjacent concentric circles is d, which ensures that the distance between constellation points on different concentric circles is greater than or equal to d, thereby ensuring a certain bit error rate.

[0041] In this embodiment, d=1. In other embodiments, d may be adjusted according to the specific arrangement of constellation points on the constellation diagram.

[0042] Optionally, in this embodiment 2 n Any three of the constellation points are located on the curve, resulting in a staggered arrangement of the constellation points. This improves the uniformity of the constellation point arrangement, further compacts the constellation points, and further reduces redundant space on the circumference. Therefore, the PAPR of QAM high-order modulation can be further reduced.

[0043] In a specific embodiment, if Figure 4 As shown, Figure 4 This application is 16QAM constellation Figure 1 Schematic diagram of the structure of the embodiment. The constellation diagram of this embodiment includes 16 constellation points, and the 16 constellation points are distributed on the circumferences of two concentric circles with different radii.

[0044] In this embodiment, 5 constellation points are allocated on the circumference of the first concentric circle of the constellation diagram, and 11 constellation points are allocated on the circumference of the second concentric circle of the constellation diagram.

[0045] In this embodiment, the radius of the first concentric circle of the constellation diagram is R1 = 1 / (2*sin(π / 5)), and the radius of the second concentric circle of the constellation diagram is R2 = 1 / (2*sin(π / 5) + d). In this embodiment, d = 1, that is, R2 = 1 / (2*sin(π / 5) + 1.

[0046] Based on the same bit error rate constraint (same d), for 16 constellation points, the 16QAM of the concentric circle structure in this embodiment is the same as Figure 1 Compared with the medium rectangular 16QAM, its average power is 0.1dB higher and PAPR is 1.3dB lower.

[0047] For 16 constellation points, such as Figure 5 The concentric circle structure of 16APSK has a PAPR 1.1dB lower than that of rectangular 16QAM, but the average power needs to be increased by 0.7dB. Obviously, the concentric circle structure of 16QAM in this embodiment can achieve a lower PAPR at a lower average power cost than the concentric circle structure of 16APSK.

[0048] In another specific embodiment, Figure 6 As shown, Figure 6 This application is 64QAM constellation Figure 1 Schematic diagram of the structure of the embodiment. The constellation diagram of this embodiment includes 64 constellation points, and the 64 constellation points are distributed on the circumferences of four concentric circles with different radii.

[0049] Among them, 7 constellation points are allocated on the circumference of the first concentric circle of the constellation diagram in this embodiment, 13 constellation points are allocated on the circumference of the second concentric circle of the constellation diagram, 19 constellation points are allocated on the circumference of the first concentric circle of the constellation diagram, and 25 constellation points are allocated on the circumference of the second concentric circle of the constellation diagram.

[0050] In this embodiment, the radius of the first concentric circle of the constellation diagram is R1=1 / (2*sin(π / 7)), the radius of the second concentric circle of the constellation diagram is R2=1 / (2*sin(π / 7))+d, the radius of the third concentric circle of the constellation diagram is R3=1 / (2*sin(π / 7))+2*d, and the radius of the fourth concentric circle of the constellation diagram is R4=1 / (2*sin(π / 7))+3*d. In this embodiment, d=1, that is, R2=1 / (2*sin(π / 7)+1, R3=1 / (2*sin(π / 7))+2, and R4=1 / (2*sin(π / 7))+3.

[0051] Based on the same bit error rate constraint (same d), for 64 constellation points, the 64QAM of the concentric circle structure in this embodiment is the same as Figure 2 Compared with the medium rectangular 64QAM, its average power is 0.1dB higher and PAPR is 1.6dB lower.

[0052] In another embodiment, the radius R of the (m+1)th concentric circle is m+1 =R m +d, where R m is the radius of the mth concentric circle, and the radius of the first concentric circle is R1 = 1 / (2*sin(π / 4)). Where d is the minimum distance between two constellation points that achieves a certain bit error rate performance.

[0053] It can be seen that in this embodiment, the radius of the first concentric circle is the smallest, and the radius of the Ath concentric circle is the largest.

[0054] This embodiment optimizes the radius of each concentric circle to achieve better performance (further reducing the average power penalty). Therefore, the QAM constellation diagram of this application can achieve PAPR reduction at a lower average power penalty. The radius difference between two adjacent concentric circles is d, which ensures that the distance between constellation points on different concentric circles is greater than or equal to d, thereby ensuring a certain bit error rate.

[0055] In this embodiment, d=1. In other embodiments, d may be adjusted according to the specific arrangement of constellation points on the constellation diagram.

[0056] In another specific embodiment, the constellation diagram includes 256 constellation points, and the 256 constellation points are distributed on the circumferences of 9 concentric circles with different radii.

[0057] Among them, 4 constellation points are allocated on the circumference of the first concentric circle of the constellation diagram of this embodiment, 10 constellation points are allocated on the circumference of the second concentric circle of the constellation diagram, 16 constellation points are allocated on the circumference of the third concentric circle of the constellation diagram, 23 constellation points are allocated on the circumference of the fourth concentric circle of the constellation diagram, 29 constellation points are allocated on the circumference of the fifth concentric circle of the constellation diagram, 35 constellation points are allocated on the circumference of the sixth concentric circle of the constellation diagram, 42 constellation points are allocated on the circumference of the seventh concentric circle of the constellation diagram, 48 constellation points are allocated on the circumference of the eighth concentric circle of the constellation diagram, and 49 constellation points are allocated on the circumference of the ninth concentric circle of the constellation diagram.

[0058] In this embodiment, the radius of the first concentric circle of the constellation diagram is R1=1 / (2*sin(π / 4)), the radius of the second concentric circle of the constellation diagram is R2=1 / (2*sin(π / 4))+d, the radius of the third concentric circle of the constellation diagram is R3=1 / (2*sin(π / 4))+2*d, the radius of the fourth concentric circle of the constellation diagram is R4=1 / (2*sin(π / 4))+3*d, and the radius of the fifth concentric circle of the constellation diagram is R5=1 / (2*sin(π / 4))+4*d, the radius of the sixth concentric circle of the constellation diagram R6=1 / (2*sin(π / 4))+5*d, the radius of the seventh concentric circle of the constellation diagram R7=1 / (2*sin(π / 4))+6*d, the radius of the eighth concentric circle of the constellation diagram R8=1 / (2*sin(π / 4))+7*d, and the radius of the ninth concentric circle of the constellation diagram R9=1 / (2*sin(π / 4))+8*d. In this embodiment, d=1, that is, R2=1 / (2*sin(π / 5)+1, R3=1 / (2*sin(π / 4))+2, R4=1 / (2*sin(π / 4))+3, R5=1 / (2*sin(π / 4) ))+4, R6=1 / (2*sin(π / 4))+5, R7=1 / (2*sin(π / 4))+6, R8=1 / (2*sin(π / 4))+7, R9=1 / (2*sin(π / 4))+8.

[0059] Based on the same bit error rate constraint (same d), for 256 constellation points, the concentric circle structure 256QAM of this embodiment has an average power 0.1 dB higher and a PAPR 1.6 dB lower than the rectangular 256QAM.

[0060] In another specific embodiment, the constellation diagram of this embodiment includes 1024 constellation points, and the 1024 constellation points are distributed on the circumferences of 18 concentric circles with different radii.

[0061] In this embodiment, the numbers of constellation points allocated on the circumferences of the 18 concentric circles are 4, 10, 16, 23, 29, 35, 42, 48, 49, 54, 60, 67, 73, 79, 86, 92, 98, 104, and 104 respectively.

[0062] In this embodiment, the radii of the first to eighteenth concentric circles are as follows: R1=1 / (2*sin(π / 4)), R2=1 / (2*sin(π / 4))+*d, R3=1 / (2*sin(π / 4))+2*d, R4=1 / (2*sin(π / 4))+3*d, R5=1 / (2*sin(π / 4))+4*d, R6=1 / (2*sin(π / 4))+5*d, R7=1 / (2*sin(π / 4))+6*d, R8=1 / (2*sin(π / 4))+7*d, R9=1 / (2*sin(π / 4))+8*d, R 10 =1 / (2*sin(π / 4))+9*d、R 11 =1 / (2*sin(π / 4))+10*d、R 12 =1 / (2*sin(π / 4))+11*d、R 13 =1 / (2*sin(π / 4))+12*d、R 14 =1 / (2*sin(π / 4))+13*d、R 15 =1 / (2*sin(π / 4))+14*d、R 16 =1 / (2*sin(π / 4))+15*d、R 17 =1 / (2*sin(π / 4))+16*d、R 18 =1 / (2*sin(π / 4))+17*d.

[0063] In this embodiment, d=1, that is, R2=1 / (2*sin(π / 4))+1, R3=1 / (2*sin(π / 4))+2, R4=1 / (2*sin(π / 4))+3, R5=1 / (2*sin(π / 4) ))+4, R6=1 / (2*sin(π / 4))+5, R7=1 / (2*sin(π / 4))+6, R8=1 / (2*sin(π / 4))+7, R9=1 / (2*sin(π / 4))+8, R 10 =1 / (2*sin(π / 4))+9, R 11 =1 / (2*sin(π / 4))+10, R 12 =1 / (2*sin(π / 4))+11, R 13 =1 / (2*sin(π / 4))+12, R 14=1 / (2*sin(π / 4))+13, R 15 =1 / (2*sin(π / 4))+14, R 16 =1 / (2*sin(π / 4))+15, R 17 =1 / (2*sin(π / 4))+16, R 18 =1 / (2*sin(π / 4))+17.

[0064] Based on the same bit error rate constraint (same d), for 256 constellation points, the concentric circle structure 256QAM of this embodiment has an average power 0.1 dB higher and a PAPR 1.7 dB lower than the rectangular 256QAM.

[0065] This application further proposes a modulator, such as Figure 7 As shown, Figure 7 Schematic diagram of the structure of an embodiment of a modulator of the present application. Modulator 70 of this embodiment includes: an orthogonal signal generation module 71, a mapping module 72, and a memory 73. The orthogonal signal generation module 71 is configured to generate orthogonal I and Q signals from a bit stream acquired from a channel; the mapping module 72 is coupled to the orthogonal signal generation module 71 and configured to map the I and Q signals onto a constellation diagram to obtain a QAM signal; and the memory 73 is coupled to the mapping module 72 and configured to store the constellation diagram.

[0066] The constellation diagram of this embodiment is the constellation diagram constructed by the QAM constellation diagram design method of the above embodiment.

[0067] After channel coding, data is mapped onto a constellation diagram. A signal has three characteristics that vary over time: amplitude, phase, or frequency. In specialized systems, the signal can be decomposed into a set of independent components: an in-phase I component and a quadrature Q component. These two components are orthogonal and independent of each other.

[0068] For 64QAM, the binary MPEG-2 bit stream that has been channel-coded enters the QAM modulator, and the signal is divided into two paths, one for I and the other for Q. Each path is given a 3-bit binary number at a time. This 3-bit binary number has a total of 8 different states, corresponding to 8 different level amplitudes. In this way, I has 8 levels with different amplitudes, Q has 8 levels with different amplitudes, and the I and Q signals are orthogonal. In this way, any combination of the amplitude of I and any amplitude of Q will be mapped to a corresponding constellation point on the polar coordinates, so that each constellation point represents a mapping composed of 6 bits of data. I and Q have a total of 8*8, a total of 64 combination states. The various possible data state combinations are finally mapped to the constellation diagram as follows: Figure 6 The 64QAM constellation diagram shown.

[0069] Different from the prior art, the QAM constellation diagram of this embodiment uses 2 n The constellation points are distributed along the circumference of multiple concentric circles of different radii, and the phases of the constellation points on each circle are evenly distributed within a 360-degree plane. This overcomes the limitation on the number of constellation points per ring, allowing for a dense arrangement of constellation points and reducing redundant space on the circumference. Therefore, the QAM constellation diagram of this application can reduce the PAPR of QAM high-order modulation.

[0070] This application further proposes a computer storage medium, such as Figure 8 As shown, Figure 8 The computer storage medium 80 stores program instructions 81, which, when executed by a processor (not shown), implement the above-mentioned QAM constellation design method.

[0071] The computer storage medium 80 in this embodiment can be, but is not limited to, a USB flash drive, an SD card, a PD optical drive, a mobile hard drive, a large-capacity floppy drive, a flash memory, a multimedia memory card, a server, etc.

[0072] The QAM constellation design method of the embodiment of the present application includes: obtaining the number of symbols M required for QAM modulation and the number of bits n of each symbol, where M=2 n ; 2 n The constellation points are distributed on the circumference of multiple concentric circles with different radii in a two-dimensional plane, and the phases of the constellation points on the same concentric circle are evenly distributed in the 360° plane; the mapping code of the constellation points in the modulation is determined to obtain the optimal mapping code set, that is, the complete constellation diagram, wherein the mapping code is an n-bit binary number. The QAM constellation diagram constructed by the QAM constellation diagram design method of the embodiment of the present application is 2 n The constellation points are distributed along the circumference of multiple concentric circles of different radii, and the phases of the constellation points on each circle are evenly distributed within a 360-degree plane. This overcomes the limitation on the number of constellation points per ring, allowing for a dense arrangement of constellation points and reducing redundant space on the circumference. Therefore, the QAM constellation diagram of this application can reduce the PAPR of QAM high-order modulation.

[0073] Furthermore, the embodiment of the present application optimizes the radius of each concentric circle to achieve better performance (further reducing the average power cost). Therefore, the QAM constellation diagram of the present application can achieve PAPR reduction at a lower average power cost.

[0074] In addition, if the above functions are implemented as software functions and sold or used as independent products, they can be stored in a storage medium readable by a mobile terminal. That is, the present application also provides a storage device storing program data, which can be executed to implement the methods of the above embodiments. The storage device can be, for example, a USB flash drive, an optical disk, a server, etc. In other words, the present application can be embodied in the form of a software product, which includes a number of instructions for causing a smart terminal to execute all or part of the steps of the methods described in each embodiment.

[0075] In the description of the present application, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0076] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. Throughout the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0077] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may be performed out of the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present application belong.

[0078] The logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing the logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (which can be a personal computer, server, network device, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device). For purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include the following: an electrical connection with one or more wires (electronic devices), a portable computer disk cartridge (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and programmable read-only memory (EPROM or flash memory), fiber optic devices, and a portable compact disc read-only memory (CDROM). Furthermore, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing it in another suitable manner if necessary, and then storing it in a computer memory.

[0079] The above description is only an implementation method of the present application and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the description and drawings of this application, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A QAM constellation design method, characterized in that: include: Get the number of symbols M and the number of bits per symbol n required for QAM modulation, where M = 2 n ; 2 n The constellation points are distributed on the circumferences of a plurality of concentric circles with different radii in a two-dimensional plane, and the phases of the constellation points on the same concentric circle are evenly distributed in a 360° plane; Determine the mapping code of the constellation point in modulation to obtain an optimal mapping code set, that is, a complete constellation diagram, wherein the mapping code is an n-bit binary number.

2. The QAM constellation design method according to claim 1, wherein: The radius R of the (m+1)th concentric circle m+1 =R m +d, where R m is the radius of the mth concentric circle, the radius of the first concentric circle R1=1 / (2sin(π / (n+1))), and d is the minimum distance between two constellation points under a preset bit error rate.

3. The QAM constellation design method according to claim 2, wherein: The constellation diagram includes 16 constellation points, and the 16 constellation points are distributed on the circumferences of two concentric circles with different radii; Wherein, 5 constellation points are allocated on the circumference of the first concentric circle of the constellation diagram, and 11 constellation points are allocated on the circumference of the second concentric circle of the constellation diagram; The radius of the first concentric circle of the constellation diagram is R1=1 / (2*sin(π / 5)), and the radius of the second concentric circle of the constellation diagram is R2=1 / (2*sin(π / 5)+d).

4. The QAM constellation design method according to claim 2, wherein: The constellation diagram includes 64 constellation points, and the 64 constellation points are distributed on the circumferences of the four concentric circles with different radii; Wherein, 7 constellation points are allocated on the circumference of the first concentric circle of the constellation diagram, 13 constellation points are allocated on the circumference of the second concentric circle of the constellation diagram, 19 constellation points are allocated on the circumference of the first concentric circle of the constellation diagram, and 25 constellation points are allocated on the circumference of the second concentric circle of the constellation diagram; The radius of the first concentric circle of the constellation diagram is R1 = 1 / (2*sin(π / 7)), the radius of the second concentric circle of the constellation diagram is R2 = 1 / (2*sin(π / 7)) + d, the radius of the third concentric circle of the constellation diagram is R3 = 1 / (2*sin(π / 7)) + 2*d, and the radius of the fourth concentric circle of the constellation diagram is R4 = 1 / (2*sin(π / 7)) + 3*d.

5. The QAM constellation design method according to claim 1, wherein: The radius R of the (m+1)th concentric circle m+1 =R m +d, where R m is the radius of the mth concentric circle, the radius of the first concentric circle R1=1 / (2*sin(π / 4)), and d is the minimum distance between two constellation points under a preset bit error rate.

6. The QAM constellation design method according to claim 5, characterized in that: The constellation diagram includes 256 constellation points, and the 256 constellation points are distributed on the circumferences of 9 concentric circles with different radii; Wherein, 4 constellation points are allocated on the circumference of the first concentric circles of the constellation diagram, 10 constellation points are allocated on the circumference of the second concentric circles of the constellation diagram, 16 constellation points are allocated on the circumference of the third concentric circles of the constellation diagram, 23 constellation points are allocated on the circumference of the fourth concentric circles of the constellation diagram, 29 constellation points are allocated on the circumference of the fifth concentric circles of the constellation diagram, 35 constellation points are allocated on the circumference of the sixth concentric circles of the constellation diagram, 42 constellation points are allocated on the circumference of the seventh concentric circles of the constellation diagram, 48 constellation points are allocated on the circumference of the eighth concentric circles of the constellation diagram, and 49 constellation points are allocated on the circumference of the ninth concentric circles of the constellation diagram; The radius of the first concentric circle of the constellation diagram is R1=1 / (2*sin(π / 4)), the radius of the second concentric circle of the constellation diagram is R2=1 / (2*sin(π / 4))+d, the radius of the third concentric circle of the constellation diagram is R3=1 / (2*sin(π / 4))+2*d, the radius of the fourth concentric circle of the constellation diagram is R4=1 / (2*sin(π / 4))+3*d, and the radius of the fifth concentric circle of the constellation diagram is R5=1 / (2*sin(π / 4))+4*d, the radius of the sixth concentric circle of the constellation diagram R6=1 / (2*sin(π / 4))+5*d, the radius of the seventh concentric circle of the constellation diagram R7=1 / (2*sin(π / 4))+6*d, the radius of the eighth concentric circle of the constellation diagram R8=1 / (2*sin(π / 4))+7*d, and the radius of the ninth concentric circle of the constellation diagram R9=1 / (2*sin(π / 4))+8*d.

7. The QAM constellation design method according to claim 5, wherein: The constellation diagram includes 1024 constellation points, and the 1024 constellation points are distributed on the circumferences of 18 concentric circles with different radii; The numbers of the constellation points allocated on the circumferences of the 18 concentric circles with different radii are 4, 10, 16, 23, 29, 35, 42, 48, 49, 54, 60, 67, 73, 79, 86, 92, 98, 104, and 104 respectively; The radius of the first concentric circle to the radius of the eighteenth concentric circle are: R1 = 1 / (2*sin(π / 4)), R2 = 1 / (2*sin(π / 4)) + d, R3 = 1 / (2*sin(π / 4)) + 2*d, R4 = 1 / (2*sin(π / 4)) + 3*d, R5 = 1 / (2*sin(π / 4)) + 4*d, R6 = 1 / (2*sin(π / 4)) + 5*d, R7 = 1 / (2*sin(π / 4)) + 6*d, R8 = 1 / (2*sin(π / 4)) + 7*d, R9 = 1 / (2*sin(π / 4)) + 8*d, R 10 =1 / (2*sin(π / 4))+9*d、R 11 =1 / (2*sin(π / 4))+10*d、R 12 =1 / (2*sin(π / 4))+11*d、R 13 =1 / (2*sin(π / 4))+12*d、R 14 =1 / (2*sin(π / 4))+13*d、R 15 =1 / (2*sin(π / 4))+14*d、R 16 =1 / (2*sin(π / 4))+15*d、R 17 =1 / (2*sin(π / 4))+16*d、R 18 =1 / (2*sin(π / 4))+17*d.

8. The QAM constellation design method according to claim 1, wherein: Any three constellation points among the 2n constellation points are located on the curve.

9. A modulator, characterized in that The modulator comprises: An orthogonal signal generation module is used to generate orthogonal I-channel and Q-channel signals from the bit stream obtained from the channel; a mapping module coupled to the orthogonal signal generating module, the mapping module being configured to map the I-path signal and the Q-path signal to the constellation diagram according to any one of claims 1 to 8 to obtain a QAM signal; A memory coupled to the mapping module, wherein the memory is used to store the constellation diagram according to any one of claims 1 to 8.

10. A computer storage medium, characterized in that Program instructions are stored thereon, and when the program instructions are executed, the QAM constellation diagram design method described in any one of claims 1 to 8 is implemented.

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