Spatial modulation method for symbol set design based on switch index

Abstract

The invention relates to a spatial modulation method for symbol group set design based on a switch index, which comprises the following steps of: acquiring information bits of the switch index, and designing a symbol group selector based on switch control; under the control of the switch index information bits, inputting the symbol group index information bits into a symbol group selector to obtain a specified symbol group set; wherein the symbol group set is obtained by utilizing a preset cycle condition and a construction algorithm model; dividing the specified symbol group, processing the components of the symbol group, and modulating signal constellations of two quadrants to obtain new components; and inputting the new components into a permutation combiner for sorting to obtain a new space vector, and further forming an emission space vector.

Description

Technical Field

[0001] The invention relates to the technical field of wireless communications, and in particular to a spatial modulation method based on a symbol set design based on a switch index. Background Art

[0002] In the past decade, multiple-input multiple-output index modulation (MIMO-IM) has developed into a key technology with great potential. This technology can relatively improve the spectrum utilization and reduce the detection complexity of the receiver by utilizing multiple index domains (such as the spatial domain of the transmitting antenna, the switch index domain, and the symbol group index). In the generalized spatial modulation (GSM) scheme, multiple antennas are activated simultaneously to modulate multiple quadrature amplitude modulation (QAM) constellation points (CPs) to improve the spectrum utilization of the MIMO-IM system, but at the cost of complex detection of the received signal. Enhanced spatial modulation (ESM), by combining with the variable number of activated antennas, uses an interpolation method to design the signal CP to increase the squared minimum Euclidean distance (MED) between the transmission space vectors. To further improve the squared MED, the orthogonal index modulation based on three-dimensional constellation (QIM-TDC) expands the dimension of the signal CP, while the switch and vector index domains are developed in GSM based on multi-index modulation (GSM-MIM). Furthermore, the spatial constellation design (SM-SC) scheme based on spatial modulation uses the symbol group index and antenna index to carry additional information. Subsequently, based on the permutation method, the permutation, symbol group and antenna index joint spatial modulation (JPGA-ISM) scheme is further used to improve the ability to carry additional information. Although SM-SC and JPGA-ISM improve the additional information of the MIMO-IM system, the component values ​​of the symbol group of SM-SC are single, and the components in the transmit vector in both schemes are single values. Summary of the invention

[0003] In order to solve the problems existing in the above-mentioned prior art, the purpose of the present invention is to provide a spatial modulation method for symbol set design based on switch index, and under the control of the switch index, multiple symbol sets are designed by a permutation and combination method. Secondly, in order to alleviate the single value of the components in the transmission vector, multiple two-quadrant QAM (TQAM) constellation points are modulated by symbol groups.

[0004] To achieve the above object, the present invention provides the following solutions:

[0005] The spatial modulation method based on the symbol set design of the switch index includes:

[0006] Obtain switch index information bits and design a symbol group selector based on switch control;

[0007] Under the control of the switch index information bit, the symbol group index information bit is input into the symbol group selector to obtain a specified symbol group set; wherein the symbol group set is obtained by using a preset loop condition and a construction algorithm model;

[0008] Componentizing the designated symbol group, processing the components of the symbol group, and modulating the signal constellations of two quadrants to obtain new components;

[0009] The new components are input into the permutation combiner for sorting, a new space vector is obtained, and a transmission space vector is further formed.

[0010] Optionally, the symbol group selector comprises:

[0011] A B→D converter, used to convert the binary bits of the switch index information into a decimal number;

[0012] 1×D switch controller, used to control the input symbol group index information and select the corresponding symbol group set selector through switch control under the control of the converted switch index information;

[0013] A plurality of symbol set selectors are used to configure a symbol set in each of the symbol set selectors.

[0014] Optionally, obtaining the symbol group includes:

[0015] Using symbolic matrices Construct D types of symbol groups: Π1, L, Π D , where the symbol group set

[0016] Set the loop condition: 1≤γ≤λ;

[0017] If γ = 1, the first type of symbol set Π1 is expressed as:

[0018]

[0019] The resulting symbol matrix Middle 2 λ The column vector corresponds to the symbol group set Π1 in 2 λ symbol groups;

[0020] If γ = λ, then the symbol set Π of the λth type λ It is expressed as:

[0021]

[0022] The resulting symbol matrix Middle 2 λ The column vector corresponds to the symbol group set Π λMiddle 2 λ symbol groups;

[0023] If γ≠λ, then the symbol set Π of the γth type γ It is expressed as:

[0024]

[0025] The resulting symbol matrix Middle 2 λ The column vector corresponds to the symbol group set Π γ Middle 2 λ symbol groups;

[0026] Among them, Π1 is the first type of symbol group set, B is the symbol matrix The vector after the value of the γth row component is doubled, is a symbolic matrix The 2nd to λth row vectors in λ is the symbol group of the λth type, is a symbolic matrix The 1st to λ-1th row vectors in γ is the symbol group of the γth type, is a symbolic matrix The 1st to γ-1th row vectors in is a symbolic matrix The vectors of the γ+1th to λth rows in ;

[0027] Based on the above algorithm design, we get λ types of symbol groups: Π1, L, Π λ , from the set of λ types of symbol groups Π1,L,Π λ Select the legal D types of symbol groups: Π1, L, Π d ,L,Π D .

[0028] Optionally, obtain the symbol matrix The method of increasing the value of the γth row component of the vector B by two times is:

[0029]

[0030] Where c is a constant, is a symbolic matrix The γth row vector of .

[0031] Optionally, obtain the symbol matrix include:

[0032] Constructing a symbolic matrix Based on the constructed symbol matrix Constructing a symbolic matrix Through the symbol matrix Get the symbol matrix

[0033] Construct the symbol matrix include:

[0034] Set the loop condition: 1≤ε≤2 2 ;

[0035] If ε≤2 2 / 2, then the symbol matrix The ε-th column vector in is expressed as:

[0036]

[0037] If ε>2 2 / 2, then the symbol matrix The ε-th column vector in is expressed as:

[0038]

[0039] Get the symbol matrix include:

[0040] Set the loop condition: 1≤ε≤2 λ ;

[0041] If ε≤2 λ / 2, then the symbol matrix The ε-th column vector in is expressed as:

[0042]

[0043] If ε>2 λ / 2, then the symbol matrix The ε-th column vector in is expressed as:

[0044]

[0045] Where a is 1, is a symbolic matrix The εth column vector in , b is the imaginary symbol j, is a symbolic matrix ε-2 in 2 / 2 column vector, is a symbolic matrix The ε-th column vector in , is a symbolic matrix The ε-th column vector in , is a symbolic matrix ε-2 in λ / 2 column vector.

[0046] Optionally, processing the components of the symbol group includes:

[0047] Set the judgment for the selected symbol group Medium value and its corresponding component index number;

[0048] Selecting a component of the symbol group according to the decision component value and its corresponding component index number, and obtaining the component index number and its corresponding component of the symbol group;

[0049] Based on information bits Control, set the adjustment component to process the component corresponding to the component index number:

[0050]

[0051] Where j is the imaginary number symbol, is the new component after the modulation component value is processed, For the selected symbol group The component corresponding to component index p in For a rotation angle of 90 degrees, is the information bit, and p is the value corresponding to the component Time component index number, d is the information bit Converted to decimal and added "1" to represent the number, e is the information bit I GI Convert to decimal and add "1" to represent the number.

[0052] Optionally, the method for obtaining the new component is:

[0053]

[0054] in, is the i-th new component after the modulation component value is processed, is the new component after the modulation component value is processed, is the τth i The signal constellation point symbol in the TQAM signal constellation, For the selected symbol group The component corresponding to the component index number i in , λ is the row dimension of the symbol matrix, and i is the component number of the vector.

[0055] Optionally, the method for obtaining the new space vector is:

[0056]

[0057] Where x is the new space vector, x(λ) is the λth component of the space vector x, which corresponds to the modulation component value The new component after processing

[0058] Optionally, forming the transmit space vector includes:

[0059] Based on the antenna index vector information bits, a vector is specified from the antenna index vector set, so that the new space vector is modulated on the activated target antenna to form the transmission space vector.

[0060] The beneficial effects of the present invention are:

[0061] The present invention develops various types of symbol groups under the control of switch index information, based on preset loop conditions and constructed algorithm models, to improve the ability to carry additional information. Secondly, in order to alleviate the single value of components in the transmission vector, the symbol group indexes additional information, and from the symbol group selected from the symbol group set, except for a specific component controlled by a switch, the remaining components are used to modulate the two-dimensional signal constellation points, wherein (1) in order to reduce the average energy of each transmission space vector, a specific component in the selected symbol group is modulated into a new component by a switch; (2) the remaining components in the selected symbol group are used to modulate the signal points based on the two-quadrant QAM constellation; finally, the transmission space vector is generated by using a permutation combiner and a transmission space vector generator, aiming to increase the square minimum Euclidean distance between the two transmission space vectors, and further enhance the reliability of wireless communication. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0063] Figure 1 A schematic diagram of a spatial modulation method designed based on a switch index symbol set according to an embodiment of the present invention;

[0064] Figure 2 A symbol group selector controlled by a switch according to an embodiment of the present invention. DETAILED DESCRIPTION

[0065] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0066] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0067] like Figure 1 As shown, this embodiment discloses a spatial modulation method for symbol group set design based on switch index, including: obtaining switch index information bits, designing a symbol group selector based on switch control; under the control of the switch index information bits, inputting the symbol group index information bits into the symbol group selector to obtain a specified symbol group set; wherein the symbol group set is obtained by using a preset loop condition and a constructed algorithm model; dividing the specified symbol group into components, processing the components of the symbol group, and modulating the signal constellation of two quadrants to obtain new components; inputting the new components into a permutator and combining them for sorting to obtain a new space vector, and further forming a transmission space vector.

[0068] Furthermore, the symbol group selector includes: a B→D converter, used to convert the binary bits of the switch index information into a decimal number; a 1×D switch controller, used to control the input symbol group index information through the switch and select the corresponding symbol group set selector under the control of the converted switch index information; and a plurality of symbol group set selectors, used to configure symbol groups in each symbol group set selector.

[0069] Specifically,

[0070] Step 1: Design a 1×D switch controller based on control switch k1, that is, a controller with 1 input port corresponding to D output ports, and a control switch k1, D satisfies the power of 2, the purpose is to control and select the corresponding symbol group selector through the switch, such as Figure 2 The 1×D switch controller is shown in the box. Figure 2 middle, I GI and is a binary bit stream, which respectively represents the symbol group index information and the switch index information of the control switch k1, d is a decimal number, and the B→D converter is a binary-to-decimal converter.

[0071] Step 2: If Figure 2 As shown, the switch index information bit Under control, the 1×D switch controller converts the input symbol group index information bit I GI Output at the designated d-th output port and input to the d-th symbol group selector among the D symbol group selectors, where d is the information bit Convert to decimal and add "1" to represent the number;

[0072] Step 3: In each symbol group selector, a symbol group set is configured for information bit I GIThe present invention designs D types of symbol sets Π1, L, Π d ,L,Π D The construction algorithm is as follows:

[0073] Input: λ>1, a=1, b=j, c=2,

[0074] Output: D types of symbol groups: Π1, L, Π d ,L,Π D ;

[0075] By using symbolic matrix Construct D types of symbol groups: Π1, L, Π d ,L,Π D , where the symbol group set Assume a symbolic matrix A 1×2 =[1j]. Based on the symbol matrix A 1×2 , we can construct the symbol matrix That is, when λ=2. Construct the symbol matrix The algorithm design is as follows:

[0076] Execute loop statements:

[0077] The loop condition is: 1≤ε≤2 2 ;

[0078] Execute the conditional statement:

[0079] If ε≤2 2 / 2, then the symbol matrix The ε-th column vector in can be expressed as:

[0080]

[0081] If ε>2 2 / 2, then the symbol matrix The ε-th column vector in can be expressed as:

[0082]

[0083] End conditional statement:

[0084] End loop statement:

[0085] Similarly, repeat the above construction of symbol matrix The algorithm design method can construct a symbolic matrix

[0086]

[0087] About symbolic matrices It can be obtained through the following design method:

[0088] Execute loop statements:

[0089] The loop condition is: 1≤ε≤2 λ ;

[0090] Execute the conditional statement:

[0091] If ε≤2 λ / 2, then the symbol matrix The ε-th column vector in can be expressed as:

[0092]

[0093] If ε>2 λ / 2, then the symbol matrix The ε-th column vector in can be expressed as:

[0094]

[0095] End conditional statement:

[0096] End loop statement:

[0097] Then, in the symbol matrix Based on this, we construct λ symbol groups Π1,L,Π d ,L,Π λ , as follows: Execute the loop statement:

[0098] The cycle conditions are: 1≤γ≤λ;

[0099] First execute Then, execute the conditional statement:

[0100] If γ = 1, the first type of symbol group Π1 can be expressed as:

[0101] Among them, the symbol matrix obtained by Middle 2 λ The column vector corresponds to the symbol group set Π1 in 2 λ symbol groups.

[0102] Otherwise, if γ = λ, then the symbol set Π of the λth type λ It can be expressed as:

[0103] Among them, the symbol matrix obtained by Middle 2 λ The column vector corresponds to the symbol group set Π λ Middle 2 λ symbol groups.

[0104] Otherwise, if γ≠λ, then the set of symbol groups of type γ Π γ It can be expressed as:

[0105] Among them, the symbol matrix obtained by Middle 2 λ The column vector corresponds to the symbol group set Π γ Middle 2 λ symbol groups.

[0106] End conditional statement:

[0107] End loop statement:

[0108] According to the above algorithm design, we can get λ types of symbol groups: Π1, L, Π d ,L,Π λ Each symbol group contains 2 λ symbol groups, i.e. the dth symbol group set Each symbol group contains λ components. Then, the set of λ symbol groups Π1,L,Π obtained from the above algorithm is d ,L,Π λ Select D symbol groups as D types of symbol groups: Π1, L, Π d ,L,Π D .

[0109] Step 4: If Figure 1 As shown, in the specified d-th symbol group selector, the symbol group index information bit I GI For selecting from symbol group Specify a symbol group in e is the information bit I GI Convert to decimal and add "1" to represent the number. represents the dth symbol group Π d The e-th symbol group in ;

[0110] Further, processing the components of the symbol group includes: setting the decision component value and its corresponding component index number; select the component of the symbol group according to the judgment component value and its corresponding component index number, obtain the component index number and its corresponding symbol group component; based on the information bit Control, set the adjustment component to process the component corresponding to the component index number:

[0111]

[0112] Where j is the imaginary number symbol, is the new component after the modulation component value is processed, For the selected symbol group The component corresponding to component index p in For a rotation angle of 90 degrees, is the information bit, and p is the value corresponding to the component Time component index number, d is the information bit Converted to decimal and added "1" to represent the number, e is the information bit I GI Convert to decimal and add "1" to represent the number.

[0113] Specifically, step five: design the algorithm according to step three, and pass Figure 1 Component separator, symbol group specified in step 4 is divided into λ components: in,

[0114] Step 6: The symbol group specified in step 4 Design of constellation points for modulation signals. In order to avoid deteriorating the squared Euclidean distance between two transmitted vectors (E av is the average energy of the transmitted vector), the symbol group specified Medium The constellation points of a QAM signal cannot be modulated directly. For example, assuming the components Modulating a signal constellation point s = 3-1j to obtain a new component Obviously, the energy of this new component increases from 10 to 40, which is not conducive to the squared minimum Euclidean distance Thus, the specified symbol group Medium The constellation points of the QAM signal cannot be modulated. Therefore, a numerical decision device is used to determine the component value. And its corresponding component index number p. At the same time, output the index number p and the components:

[0115] Step 7, based on the analysis of step 6, and in order to transmit additional switch information, based on I S2 Information bit control, design a switch k2 modulation component value The switch control design method is as follows:

[0116]

[0117] That is to say, when When Enter the permutation combiner (such as Figure 2 ), otherwise the components First rotate the angle 90 degrees (ie, )get

[0118]

[0119] Furthermore, the method for obtaining the new component is:

[0120]

[0121] in, is the i-th new component after the modulation component value is processed, is the new component after the modulation component value is processed, is the τth i The signal constellation point symbol in the TQAM signal constellation, For the selected symbol group The component corresponding to the component index number i in , λ is the row dimension of the symbol matrix, and i is the component number of the vector.

[0122] Specifically, step eight: based on the design of step seven, the symbol group specified in step four λ-1 component Design for modulating QAM signal constellation points. If QAM signal constellation points are modulated directly, consider the symbol group-based The component contains the imaginary symbol "j", which will produce the same space vector, making it impossible to recover the information of the signal source at the receiving end.

[0123] Step 9: Based on the analysis in step 8, symbol group The modulated signal constellation can be designed as a QAM (TQAM) signal constellation based on two quadrants, that is, the signal constellation points of the first and third quadrants (or the second and fourth quadrants) in the QAM signal constellation can be used as symbol groups. Modulated signal constellation, for example: 2-TQSM: {1+j,-1-j}, 4-TQSM: {1+j,1+3j,-1-j,-1-3j}.

[0124] Step 10: Based on the analysis and design of steps 5, 6, and 9, the symbol group specified in step 4 λ-1 component Modulate the TQAM signal constellation points to obtain new components i≠p,τ i ∈{1,2,L,λ-1}. Thus, the new component in the space vector formed can be expressed as:

[0125]

[0126] In the formula, Indicates the τth iThen, the obtained new components are sent to the permutation combiner.

[0127] Furthermore, the method for obtaining a new space vector is:

[0128]

[0129] Where x is the new space vector, x(λ) is the λth component of the space vector x, which corresponds to the modulation component value The new component after processing

[0130] Specifically, step 11: in the permutation combiner, using the component index number p, the component Rearrange at the specified pth position, and the remaining components are arranged in the original order. Finally, a new space vector can be obtained:

[0131]

[0132] Further, forming the transmit space vector includes:

[0133] Based on the antenna index vector information bits, a vector is specified from the antenna index vector set, so that a new space vector is modulated on the activated target antenna to form a transmit space vector.

[0134] Specifically, step 12: generating a transmit space vector in a transmit space vector generator. Based on the antenna index vector information bit I AI , which contains The number of information bits, from the antenna index vector set Γ: {V1,L,V N} specifies the vector V τ , used to convert the space vector symbol x:[x(1),x(2),L,x(λ)] T Modulation is performed on the λ root activated antenna to form a transmit space vector Indicated in The unit vector with row position 1, specified by the vector V τ Middle non-zero elements.

[0135] The above embodiments are only descriptions of the preferred embodiments of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the protection scope determined by the claims of the present invention.

Claims

1. A spatial modulation method based on a symbol set design with a switch index, characterized in that: include: Obtain switch index information bits and design a symbol group selector based on switch control; Under the control of the switch index information bit, the symbol group index information bit is input into the symbol group selector to obtain a specified symbol group set; wherein the symbol group set is obtained by using a preset loop condition and a construction algorithm model; Componentizing the designated symbol group, processing the components of the symbol group, and modulating the signal constellations of two quadrants to obtain new components; The new components are input into the permutation combiner for sorting, a new space vector is obtained, and a transmission space vector is further formed.

2. The spatial modulation method based on switch index symbol set design according to claim 1, characterized in that: The symbol group selector comprises: A B→D converter, used to convert the binary bits of the switch index information into a decimal number; 1×D switch controller, used to control the input symbol group index information and select the corresponding symbol group set selector through the switch under the control of the converted switch index information; A plurality of symbol set selectors are used to configure a symbol set in each of the symbol set selectors.

3. The spatial modulation method based on switch index symbol set design according to claim 1, characterized in that: Acquiring the symbol set includes: Using symbolic matrices Construct D types of symbol groups: Π1, L, Π D , where the symbol group set 1≤κ≤D; Set the loop condition: 1≤γ≤λ; If γ = 1, the first type of symbol set Π1 is expressed as: The resulting symbol matrix Middle 2 λ The column vector corresponds to the symbol group set Π1 in 2 λ symbol groups; If γ = λ, then the symbol set Π of the λth type λ It is expressed as: The resulting symbol matrix Middle 2 λ The column vector corresponds to the symbol group set Π λ Middle 2 λ symbol groups; If γ≠λ, then the symbol set Π of the γth type γ It is expressed as: The resulting symbol matrix Middle 2 λ The column vector corresponds to the symbol group set Π γ Middle 2 λ symbol groups; Among them, Π1 is the first type of symbol group set, B is the symbol matrix The vector after the value of the γth row component is doubled, is a symbolic matrix The 2nd to λth row vectors in λ is the symbol group of the λth type, is a symbolic matrix The 1st to λ-1th row vectors in γ is the symbol group of the γth type, is a symbolic matrix The 1st to γ-1th row vectors in is a symbolic matrix The vectors of the γ+1th to λth rows in ; Based on the above algorithm design, we get λ types of symbol groups: Π1, L, Π λ , from the set of λ types of symbol groups Π1,L,Π λ Select the legal D types of symbol groups: Π1, L, Π d ,L,Π D .

4. The spatial modulation method based on switch index symbol set design according to claim 3, characterized in that: Get the symbol matrix The method to calculate the vector after the value of the γth row component is doubled is: Where c is a constant, is a symbolic matrix The γth row vector of .

5. The spatial modulation method based on switch index symbol set design according to claim 3, characterized in that: Get the symbol matrix include: Constructing a symbolic matrix Based on the constructed symbol matrix Constructing a symbolic matrix Through the symbol matrix Get the symbol matrix Construct the symbol matrix include: Set the loop condition: 1≤ε≤2 2 ; If ε≤2 2 / 2, then the symbol matrix The ε-th column vector in is expressed as: If ε>2 2 / 2, then the symbol matrix The ε-th column vector in is expressed as: Get the symbol matrix include: Set the loop condition: 1≤ε≤2 λ ; If ε≤2 λ / 2, then the symbol matrix The ε-th column vector in is expressed as: If ε>2 λ / 2, then the symbol matrix The ε-th column vector in is expressed as: Where a is 1, is a symbolic matrix The εth column vector in , b is the imaginary symbol j, is a symbolic matrix ε-2 in 2 / 2 column vector, is a symbolic matrix The ε-th column vector in , is a symbolic matrix The ε-th column vector in , is a symbolic matrix ε-2 in λ / 2 column vector.

6. The spatial modulation method based on switch index symbol set design according to claim 1, characterized in that: Processing the components of the symbol group includes: Set the judgment for the selected symbol group Medium value and its corresponding component index number; Selecting a component of the symbol group according to the decision component value and its corresponding component index number, and obtaining the component index number and its corresponding component of the symbol group; Based on information bits Control, set the adjustment component to process the component corresponding to the component index number: Where j is the imaginary number symbol, is the new component after the modulation component value is processed, For the selected symbol group The component corresponding to component index p in For a rotation angle of 90 degrees, is the information bit, and p is the value corresponding to the component Time component index number, d is the information bit Convert to decimal and add "1" to represent the number, e is the information bit I GI Convert to decimal and add "1" to represent the number.

7. The spatial modulation method based on switch index symbol set design according to claim 1, characterized in that: The method for obtaining the new component is: in, is the i-th new component after the modulation component value is processed, is the new component after the modulation component value is processed, is the τth i The signal constellation point symbol in the TQAM signal constellation, For the selected symbol group The component corresponding to the component index number i in , λ is the row dimension of the symbol matrix, and i is the component number of the vector.

8. The spatial modulation method based on switch index symbol set design according to claim 1, characterized in that: The method for obtaining the new space vector is: Where x is the new space vector, x(λ) is the λth component of the space vector x, which corresponds to the modulation component value The new component after processing 9. The spatial modulation method based on switch index symbol set design according to claim 1, characterized in that: Forming the transmit space vector comprises: Based on the antenna index vector information bits, a vector is specified from the antenna index vector set, so that the new space vector is modulated on the activated target antenna to form the transmission space vector.

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