Adaptive subcarrier and subsymbol configuration method for underwater acoustic generalized frequency division multiplexing communication based on interference minimization

Abstract

The present invention relates to the field of wireless communications, and in particular to a method for adaptively configuring subcarriers and subsymbols in underwater acoustic generalized frequency division multiplexing communications. The purpose of the present invention is to solve the problem that the inter-carrier interference and inter-symbol interference of the GFDM system in underwater acoustic communications are too high due to the multipath effect, resulting in low accuracy of channel estimation and low communication quality. After selecting the optimal configuration, the method of the present invention can significantly improve the performance of the GFDM communication system in the underwater acoustic channel. By accurately analyzing and calculating the energy of inter-subcarrier interference and inter-subsymbol interference, the optimal configuration scheme based on minimizing interference energy is selected. This scheme not only makes full use of the flexible data block structure of GFDM, but also combines interference elimination technology to enable the system to perform better in the underwater acoustic multipath channel, thereby improving the accuracy of channel estimation and communication quality.

Description

Technical Field

[0001] The present invention relates to the field of wireless communications, and in particular to a method for adaptively configuring subcarrier subsymbols in underwater acoustic generalized frequency division multiplexing communications. Background Art

[0002] As a key technology, underwater acoustic communication is widely used in military, environmental monitoring, marine science research, and other fields. However, due to the significantly greater complexity of underwater acoustic channels than terrestrial wireless channels, practical applications of underwater acoustic communication face numerous challenges. Factors such as multipath effects, time-varying characteristics, background noise, and limited bandwidth in underwater acoustic channels result in the reliability and transmission rates of high-speed underwater acoustic communication lagging behind those of terrestrial wireless communications. With the rapid development of 5G communication technology in recent years, its application in underwater acoustic communication has become a hot topic among international scholars and researchers.

[0003] In traditional underwater acoustic communication systems, Orthogonal Frequency Division Multiplexing (OFDM) technology has been widely used. This technology effectively solves the problem of multipath interference by dividing data into multiple subcarriers for transmission. However, the OFDM system also has its inherent defects. First, the OFDM system lacks flexibility and is difficult to adapt to complex underwater acoustic channel environments. Secondly, since the subcarriers in the OFDM system are orthogonal, it is difficult to fully maintain orthogonality in practical applications, resulting in serious out-of-band leakage problems in the system. In addition, the spectrum utilization rate of the OFDM system is low, especially in underwater acoustic communications, where spectrum resources are already scarce, and this problem is even more prominent.

[0004] In order to overcome these problems, Generalized Frequency Division Multiplexing (GFDM), as an emerging waveform technology, has gradually attracted the attention of the academic community. Compared with OFDM, GFDM has been improved and optimized in many aspects. First, GFDM retains the cyclic prefix (CP) structure in OFDM, which makes it easier to achieve channel equalization at the receiving end, thereby simplifying the system design. At the same time, GFDM improves spectrum efficiency by reducing the number of CPs, which is particularly important for underwater acoustic communications, because the improvement of spectrum efficiency means that more information can be transmitted under limited bandwidth. In addition, as a non-orthogonal multi-carrier transmission scheme, GFDM has flexible data block structure adjustment capabilities and can dynamically adjust transmission parameters according to changes in the underwater acoustic channel, thereby better adapting to complex underwater environments. GFDM also has a lower peak-to-average power ratio, which not only helps to reduce the nonlinear distortion of the power amplifier, but also reduces the power consumption of the system, which is also an important advantage in underwater acoustic communications.

[0005] Although GFDM offers many theoretical advantages, the complexity of underwater acoustic channels in practical applications places higher demands on the performance of GFDM systems. Previous research has primarily focused on improving GFDM channel estimation algorithms. Due to the unique physical characteristics of underwater acoustic channels, channel estimation often requires the use of pilot signals. However, the non-orthogonality between subcarriers in GFDM systems introduces additional interference during actual transmission, compromising the accuracy of channel estimation. Therefore, effectively eliminating this interference has become a key issue in the application of GFDM in underwater acoustic communications. Existing research has proposed various interference elimination methods. Commonly used methods include pilot interference cancellation and transmitter-side interference cancellation. These methods improve channel estimation accuracy by reducing inter-subcarrier self-interference during pilot design and transmission. However, these methods have limited effectiveness and still require room for improvement when dealing with complex underwater acoustic channels. In recent years, several new techniques have been proposed, such as interference-free pilot insertion, GFDM dual-filter transmission, and joint iterative channel estimation and symbol detection. These methods further improve system performance by introducing new signal processing techniques, but also increase implementation complexity. Summary of the Invention

[0006] The purpose of the present invention is to solve the problem that the inter-carrier interference and inter-symbol interference of the GFDM system in underwater acoustic communication are too high due to the multipath effect, resulting in low channel estimation accuracy and low communication quality, and to propose an adaptive configuration method of sub-carriers and sub-symbols in underwater acoustic generalized frequency division multiplexing communication based on interference minimization.

[0007] The specific process of the adaptive sub-carrier and sub-symbol configuration method for underwater acoustic generalized frequency division multiplexing communication based on interference minimization is as follows:

[0008] Step 1: Determine a binary input data consisting of 0 and 1

[0009] Step 2: Set the initial iteration count n=0, set the number of subcarriers and subsymbols to K respectively. (n) and M (n) ;

[0010] Binary input data The length is K (n) ×M (n) ;

[0011] Based on binary input data Calculate the subcarrier interference energy at iteration count n Sum sub-symbol interference energy Save the optimal number of subcarriers as K′=K (n) , the optimal number of sub-symbols is M′=M (n) ;

[0012] Step 3: Let the iteration count n=n+1, set the new number of subcarriers and subsymbols to K respectively. (n) and M (n) ;

[0013] Binary input data The length is K (n) ×M (n) ;

[0014] Based on binary input data Calculate the new subcarrier interference energy Sum sub-symbol interference energy

[0015] Compare the new subcarrier interference energy and the original subcarrier interference energy

[0016] New sub-symbol interference energy and the original sub-symbol interference energy

[0017] If the new subcarrier interference energy Less than the original retained subcarrier interference energy And the new sub-symbol interference energy Less than the original retained sub-symbol interference energy Then the optimal number of subcarriers is updated to the new number of subcarriers, and the optimal number of subsymbols is updated to the new number of subsymbols;

[0018] If the new subcarrier interference energy Less than the original retained subcarrier interference energy And the new sub-symbol interference energy Greater than or equal to the original retained sub-symbol interference energy The original subcarrier interference energy is retained and the original retained sub-symbol interference energy The corresponding number of subcarriers and subsymbols;

[0019] If the new subcarrier interference energy Greater than or equal to the original retained subcarrier interference energy And the new sub-symbol interference energy Less than the original retained sub-symbol interference energy The original subcarrier interference energy is retained and the original retained sub-symbol interference energy The corresponding number of subcarriers and subsymbols;

[0020] If the new subcarrier interference energy Greater than or equal to the original retained subcarrier interference energy And the new sub-symbol interference energy Greater than or equal to the original retained sub-symbol interference energy The original subcarrier interference energy is retained and the original retained sub-symbol interference energy The corresponding number of subcarriers and subsymbols;

[0021] Step 4: Repeat step 3 until the maximum number of iterations is reached or the number of subcarriers and the number of subsymbols do not change in N consecutive iterations, stop iteration, and save the optimal number of subcarriers and the optimal number of subsymbols.

[0022] The beneficial effects of the present invention are:

[0023] The present invention adaptively optimizes the configuration of subcarriers and subsymbols and combines interference elimination technology to enable the GFDM communication system to exhibit higher reliability and adaptability in complex underwater acoustic channels.

[0024] This paper analyzes the performance of the GFDM system itself and combines it with different multipath underwater acoustic channel models to optimize the configuration of subcarriers and subsymbols. Furthermore, by combining pilot technology with a relatively simple interference cancellation method, the present invention proposes an effective solution that can reduce inter-carrier interference (ICI) and inter-symbol interference (ISI) in the GFDM system. This improves the performance of the GFDM system while maintaining a low implementation complexity, providing new insights for the application of GFDM in underwater acoustic communications.

[0025] The proposed method for adaptive subcarrier and subsymbol configuration based on interference minimization can significantly improve the performance of GFDM communication systems in underwater acoustic channels by selecting the optimal configuration. By accurately analyzing and calculating the energy of inter-subcarrier interference and inter-subsymbol interference, the optimal configuration scheme based on interference energy minimization is selected. This scheme not only fully utilizes GFDM's flexible data block structure but also incorporates interference cancellation techniques, resulting in better system performance in underwater acoustic multipath channels, improving channel estimation accuracy and communication quality.

[0026] Experimental results show that, compared with fixed configuration methods, this method can iteratively select the subcarrier and subsymbol configuration that minimizes ISI and ICI in the current channel, thereby improving the reliability and adaptability of GFDM systems in practical applications with less complexity. This achievement is of great significance to the development of underwater communications, especially in complex marine environments, where this method can achieve more efficient and stable communications. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Flowchart of the present invention;

[0028] Figure 2 It is the GFDM symbol block diagram;

[0029] Figure 3 Provide a block diagram for the GFDM communication system;

[0030] Figure 4 Channel impulse response diagrams used in simulation: (a) underwater acoustic multipath channel 1, (b) underwater acoustic multipath channel 2;

[0031] Figure 5BER comparison diagram of GFDM communication system with different subcarrier and subsymbol configurations under three channels: (a) BER comparison diagram of GFDM communication system with different subcarrier and subsymbol configurations under Gaussian white noise channel, (b) BER comparison diagram of GFDM communication system with different subcarrier and subsymbol configurations under underwater acoustic multipath channel 1, and (c) BER comparison diagram of GFDM communication system with different subcarrier and subsymbol configurations under underwater acoustic multipath channel 2. DETAILED DESCRIPTION

[0032] Specific embodiment 1: The specific process of the method for adaptively configuring sub-carrier and sub-symbol in underwater acoustic generalized frequency division multiplexing communication based on interference minimization in this embodiment is as follows:

[0033] Step 1: Determine a binary input data consisting of 0 and 1

[0034] Step 2: Set the initial iteration count n=0, set the number of subcarriers and subsymbols to K respectively. (n) and M (n) ;

[0035] Binary input data The length is K (n) ×M (n) (For example, the sequence Length 1024, K is 2, M is 512; K is 4, M is 256; K is 256, M is 4; and so on);

[0036] Based on binary input data Calculate the subcarrier interference energy at iteration count n Sum sub-symbol interference energy Save the optimal number of subcarriers as K′=K (n) , the optimal number of sub-symbols is M′=M (n) ;

[0037] Step 3: Let the iteration count n=n+1, set the new number of subcarriers and subsymbols to K respectively. (n) and M (n) ;

[0038] Binary input data The length is K (n) ×M (n) ;

[0039] Based on binary input data Calculate the new subcarrier interference energy Sum sub-symbol interference energy

[0040] Compare the new subcarrier interference energy and the original subcarrier interference energy

[0041] New sub-symbol interference energy and the original sub-symbol interference energy

[0042] If the new subcarrier interference energy Less than the original retained subcarrier interference energy And the new sub-symbol interference energy Less than the original retained sub-symbol interference energy Then the optimal number of subcarriers is updated to the new number of subcarriers, and the optimal number of subsymbols is updated to the new number of subsymbols;

[0043] If the new subcarrier interference energy Less than the original retained subcarrier interference energy And the new sub-symbol interference energy Greater than or equal to the original retained sub-symbol interference energy The original subcarrier interference energy is retained and the original retained sub-symbol interference energy The corresponding number of subcarriers and subsymbols;

[0044] If the new subcarrier interference energy Greater than or equal to the original retained subcarrier interference energy And the new sub-symbol interference energy Less than the original retained sub-symbol interference energy The original subcarrier interference energy is retained and the original retained sub-symbol interference energy The corresponding number of subcarriers and subsymbols;

[0045] If the new subcarrier interference energy Greater than or equal to the original retained subcarrier interference energy And the new sub-symbol interference energy Greater than or equal to the original retained sub-symbol interference energy The original subcarrier interference energy is retained and the original retained sub-symbol interference energy The corresponding number of subcarriers and subsymbols;

[0046] Step 4: Repeat step 3 until the maximum number of iterations is reached or the number of subcarriers and the number of subsymbols do not change in N consecutive iterations, stop iteration, and save the optimal number of subcarriers and the optimal number of subsymbols.

[0047] Specific implementation method 2: This implementation method is different from the specific implementation method 1 in that the step 2 is based on the binary input data Calculate the subcarrier interference energy at iteration count n Sum sub-symbol interference energy The specific process is:

[0048] Step 2.1. Input binary data in sequence Perform encoding, mapping, precoding, and GFDM modulation to obtain modulated signal data;

[0049] Add a cyclic prefix (CP) to the modulated signal data to obtain the transmitted signal x(t);

[0050] Step 22: Construct a multipath channel model h(t);

[0051] Step 2: The transmitted signal x(t) passes through the multipath channel h(t) to obtain the received signal r(t);

[0052] Step 24: Based on the received signal r(t), obtain the kth subcarrier r in the received signal r(t) k Inter-carrier interference (ICI) k (t);

[0053] Step 25: Based on the received signal r(t), obtain the mth sub-symbol r in the received signal r(t) m Inter-symbol interference ISIm(t)

[0054] Step 26: Based on the mth sub-symbol r in the received signal r(t) m Inter-symbol interference (ISI) m (t), calculate the sub-symbol interference energy E ISI ;

[0055] Step 27: Based on the kth subcarrier r in the received signal r(t) k Inter-carrier interference (ICI) k (t), calculate the subcarrier interference energy E ICI .

[0056] Other steps and parameters are the same as those in the first or second embodiment.

[0057] Specific implementation method three: This implementation method is different from specific implementation methods one or two in that the binary input data is sequentially processed in step 21. Perform encoding, mapping, precoding, and GFDM modulation to obtain modulated signal data;

[0058] Add a cyclic prefix (CP) to the modulated signal data to obtain the transmitted signal x(t);

[0059] The signal x(t) is expressed as

[0060]

[0061] The GFDM signal is generalized frequency division multiplexing;

[0062] Among them, d k,m represents the data at the kth subcarrier and the mth subsymbol position, g(t) represents the filter, T represents the duration of the subsymbol, f represents the frequency interval between subcarriers, K and M represent the number of subcarriers and subsymbols respectively; t represents time; j represents the imaginary unit, j 2 =-1.

[0063] Other steps and parameters are the same as those in the first or second embodiment.

[0064] Specific embodiment 4: This embodiment differs from any one of the specific embodiments 1 to 3 in that the multipath channel model h(t) is constructed in step 22 and is expressed as

[0065]

[0066] Where L represents the number of multipaths, h l represents the amplitude of the lth multipath, τ l represents the time delay; δ(t) represents the impulse function, and h(t) represents the multipath channel.

[0067] The other steps and parameters are the same as those in the first to third embodiments.

[0068] Specific embodiment 5: This embodiment differs from any one of specific embodiments 1 to 4 in that in steps 2 and 3, the transmitted signal x(t) passes through the multipath channel h(t) to obtain the received signal r(t); the specific process is as follows:

[0069] The received signal r(t) is expressed as

[0070] r(t)=x(t)*h(t)+n(t) (3)

[0071] Where * represents convolution and n(t) represents additive noise;

[0072] Expanding the convolution operation of equation (3), the received signal r(t) can also be expressed as

[0073]

[0074] Due to the influence of multipath effect, the received signal of GFDM communication system will have subcarrier interference and subsymbol interference.

[0075] The other steps and parameters are the same as those in the first to fourth embodiments.

[0076] Specific embodiment 6: This embodiment differs from any one of specific embodiments 1 to 5 in that in step 24, based on the received signal r(t), the kth subcarrier r in the received signal r(t) is obtained. k Inter-carrier interference (ICI) k (t); The specific process is:

[0077] The kth subcarrier in the received signal r(t) is expressed as

[0078]

[0079] Among them, r k (t) represents the kth subcarrier in the received signal r(t);

[0080] ICI k (t) represents the inter-carrier interference of the k-th subcarrier;

[0081] Inter-carrier interference (ICI) of the kth subcarrier k (t) is expressed as:

[0082]

[0083] in, Indicates the subcarriers and data at the mth subsymbol position.

[0084] The other steps and parameters are the same as those in the first to fifth embodiments.

[0085] Specific embodiment 7: This embodiment differs from any one of specific embodiments 1 to 6 in that in step 25, based on the received signal r(t), the mth sub-symbol r in the received signal r(t) is obtained. m Inter-symbol interference (ISI) m (t); The specific process is:

[0086] The mth sub-symbol in the received signal r(t) is expressed as

[0087]

[0088] Among them, r m (t) represents the mth sub-symbol in the received signal r(t);

[0089] ISI m (t) represents the inter-symbol interference of the m-th sub-symbol;

[0090] The inter-symbol interference ISI of the m-th sub-symbol m (t) is expressed as:

[0091]

[0092] in, Indicates the kth subcarrier and the The data at each sub-symbol position.

[0093] In order to compare the numerical values ​​of ICI and ISI conveniently, the energy of the two is considered.

[0094] The other steps and parameters are the same as those in the first to sixth embodiments.

[0095] Specific embodiment eight: This embodiment differs from any one of specific embodiments one to seven in that the step twenty-six is ​​based on the mth sub-symbol r in the received signal r(t). m Inter-symbol interference (ISI) m (t), calculate the sub-symbol interference energy E ISI ; The expression is:

[0096]

[0097] The other steps and parameters are the same as those in the first to seventh embodiments.

[0098] Specific embodiment 9: This embodiment differs from any one of specific embodiments 1 to 8 in that the step 27 is based on the kth subcarrier r in the received signal r(t). k Inter-carrier interference (ICI) k (t), calculate the subcarrier interference energy E ICI ; The expression is:

[0099] Considering that ICI is caused by interference between subcarrier frequencies, its energy is calculated in the frequency domain;

[0100]

[0101] Among them, f k represents the center frequency of the kth subcarrier; B represents the bandwidth range of the subcarrier frequency; △f represents a continuous frequency variable; G() represents the frequency domain expression of the filter; f c Indicates the carrier frequency of the subcarrier.

[0102] The other steps and parameters are the same as those in Specific Embodiments 1 to 8.

[0103] Specific embodiment ten: This embodiment differs from any one of specific embodiments one to nine in that, in step four, 2≤N≤6.

[0104] The other steps and parameters are the same as those in Specific Embodiments 1 to 9.

[0105] The received signal r(t) corresponding to the optimal number of subcarriers and the optimal number of subsymbols is sequentially subjected to GFDM demodulation, deprecoding, demapping, and decoding to obtain binary output data. The binary output data and the binary input data are calculated. The bit error rate is calculated and the bit error rate curve is obtained under different signal-to-noise ratio conditions.

[0106] The present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A method for adaptively configuring subcarrier and subsymbol in underwater acoustic generalized frequency division multiplexing communication based on interference minimization, characterized by: The specific process of the method is: Step 1: Determine a binary input data consisting of 0 and 1 Step 2: Set the initial iteration count n=0, set the number of subcarriers and subsymbols to K respectively. (n) and M (n) ; Binary input data The length is K (n) ×M (n) ; Based on binary input data Calculate the subcarrier interference energy at iteration count n Sum sub-symbol interference energy Save the optimal number of subcarriers as K′=K (n) , the optimal number of sub-symbols is M′=M (n) ; Step 3: Let the iteration count n=n+1, set the new number of subcarriers and subsymbols to K respectively. (n) and M (n) ; Binary input data The length is K (n) ×M (n) ; Based on binary input data Calculate the new subcarrier interference energy Sum sub-symbol interference energy Compare the new subcarrier interference energy and the original subcarrier interference energy New sub-symbol interference energy and the original sub-symbol interference energy If the new subcarrier interference energy Less than the original retained subcarrier interference energy And the new sub-symbol interference energy Less than the original retained sub-symbol interference energy Then the optimal number of subcarriers is updated to the new number of subcarriers, and the optimal number of subsymbols is updated to the new number of subsymbols; If the new subcarrier interference energy Less than the original retained subcarrier interference energy And the new sub-symbol interference energy Greater than or equal to the original retained sub-symbol interference energy The original subcarrier interference energy is retained and the original retained sub-symbol interference energy The corresponding number of subcarriers and subsymbols; If the new subcarrier interference energy Greater than or equal to the original retained subcarrier interference energy And the new sub-symbol interference energy Less than the original retained sub-symbol interference energy The original subcarrier interference energy is retained and the original retained sub-symbol interference energy The corresponding number of subcarriers and subsymbols; If the new subcarrier interference energy Greater than or equal to the original retained subcarrier interference energy And the new sub-symbol interference energy Greater than or equal to the original retained sub-symbol interference energy The original subcarrier interference energy is retained and the original retained sub-symbol interference energy The corresponding number of subcarriers and subsymbols; Step 4: Repeat step 3 until the maximum number of iterations is reached or the number of subcarriers and the number of subsymbols do not change in N consecutive iterations, stop iteration, and save the optimal number of subcarriers and the optimal number of subsymbols.

2. The method for adaptively configuring subcarriers and subsymbols in underwater acoustic generalized frequency division multiplexing communication based on interference minimization according to claim 1, characterized in that: In step 2, based on binary input data Calculate the subcarrier interference energy at iteration count n Sum sub-symbol interference energy The specific process is: Step 2.

1. Input binary data in sequence Perform encoding, mapping, precoding, and GFDM modulation to obtain modulated signal data; Add a cyclic prefix to the modulated signal data to obtain the transmitted signal x(t); Step 22: Construct a multipath channel model h(t); Step 2: The transmitted signal x(t) passes through the multipath channel h(t) to obtain the received signal r(t); Step 24: Based on the received signal r(t), obtain the kth subcarrier r in the received signal r(t) k Inter-carrier interference (ICI) k (t); Step 25: Based on the received signal r(t), obtain the mth sub-symbol r in the received signal r(t) m Inter-symbol interference (ISI) m (t); Step 26: Based on the mth sub-symbol r in the received signal r(t) m Inter-symbol interference (ISI) m (t), calculate the sub-symbol interference energy E ISI ; Step 27: Based on the kth subcarrier r in the received signal r(t) k Inter-carrier interference (ICI) k (t), calculate the subcarrier interference energy E ICI .

3. The method for adaptively configuring subcarriers and subsymbols in underwater acoustic generalized frequency division multiplexing communication based on interference minimization according to claim 2, characterized in that: In the step 21, the binary input data is sequentially Perform encoding, mapping, precoding, and GFDM modulation to obtain modulated signal data; Add a cyclic prefix to the modulated signal data to obtain the transmitted signal x(t); The signal x(t) is expressed as The GFDM signal is generalized frequency division multiplexing; Among them, d k,m represents the data at the kth subcarrier and the mth subsymbol position, g(t) represents the filter, T represents the duration of the subsymbol, f represents the frequency interval between subcarriers, K and M represent the number of subcarriers and subsymbols respectively; t represents time; j represents the imaginary unit, j 2 =-1.

4. The method for adaptively configuring subcarriers and subsymbols in underwater acoustic generalized frequency division multiplexing communication based on interference minimization according to claim 3, characterized in that: In step 22, a multipath channel model h(t) is constructed, which is expressed as Where L represents the number of multipaths, h l represents the amplitude of the lth multipath, τ l represents the time delay; δ(t) represents the impulse function, and h(t) represents the multipath channel.

5. The method for adaptively configuring subcarriers and subsymbols in underwater acoustic generalized frequency division multiplexing communication based on interference minimization according to claim 4, characterized in that: In steps 2 and 3, the transmitted signal x(t) passes through the multipath channel h(t) to obtain the received signal r(t); the specific process is: The received signal r(t) is expressed as r(t)=x(t)*h(t)+n(t) (3) Where * represents convolution and n(t) represents additive noise; Expanding the convolution operation of equation (3), the received signal r(t) can also be expressed as 6. The method for adaptively configuring subcarriers and subsymbols in underwater acoustic generalized frequency division multiplexing communication based on interference minimization according to claim 5, characterized in that: In the step 24, based on the received signal r(t), the kth subcarrier r in the received signal r(t) is obtained. k Inter-carrier interference (ICI) k (t); The specific process is: The kth subcarrier in the received signal r(t) is expressed as Among them, r k (t) represents the kth subcarrier in the received signal r(t); ICI k (t) represents the inter-carrier interference of the k-th subcarrier; Inter-carrier interference (ICI) of the kth subcarrier k (t) is expressed as: in, Indicates the subcarriers and data at the mth subsymbol position.

7. The method for adaptively configuring subcarriers and subsymbols in underwater acoustic generalized frequency division multiplexing communication based on interference minimization according to claim 6, characterized in that: In the step 25, based on the received signal r(t), the mth sub-symbol r in the received signal r(t) is obtained. m Inter-symbol interference (ISI) m (t); The specific process is: The mth sub-symbol in the received signal r(t) is expressed as Among them, r m (t) represents the mth sub-symbol in the received signal r(t); ISI m (t) represents the inter-symbol interference of the m-th sub-symbol; The inter-symbol interference ISI of the m-th sub-symbol m (t) is expressed as: in, Indicates the kth subcarrier and the The data at each sub-symbol position.

8. The method for adaptively configuring subcarriers and subsymbols in underwater acoustic generalized frequency division multiplexing communication based on interference minimization according to claim 7, characterized in that: In step 26, based on the mth sub-symbol r in the received signal r(t) m Inter-symbol interference (ISI) m (t), calculate the sub-symbol interference energy E ISI ; The expression is:

9. The method for adaptively configuring subcarriers and subsymbols in underwater acoustic generalized frequency division multiplexing communication based on interference minimization according to claim 8, characterized in that: In step 27, based on the kth subcarrier r in the received signal r(t), k Inter-carrier interference (ICI) k (t), calculate the subcarrier interference energy E ICI ; The expression is: Among them, f k represents the center frequency of the kth subcarrier; B represents the bandwidth range of the subcarrier frequency; △f represents a continuous frequency variable; G() represents the frequency domain expression of the filter; f c Indicates the carrier frequency of the subcarrier.

10. The method for adaptively configuring subcarriers and subsymbols in underwater acoustic generalized frequency division multiplexing communication based on interference minimization according to claim 9, characterized in that: In the step 4, 2≤N≤6.

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