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18 April 2024, Volume 35 Issue 2
2024, 35(2):  0. 
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Disparity estimation for multi-scale multi-sensor fusion
Guoliang SUN, Shanshan PEI, Qian LONG, Sifa ZHENG, Rui YANG
2024, 35(2):  259-274.  doi:10.23919/JSEE.2023.000101
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The perception module of advanced driver assistance systems plays a vital role. Perception schemes often use a single sensor for data processing and environmental perception or adopt the information processing results of various sensors for the fusion of the detection layer. This paper proposes a multi-scale and multi-sensor data fusion strategy in the front end of perception and accomplishes a multi-sensor function disparity map generation scheme. A binocular stereo vision sensor composed of two cameras and a light deterction and ranging (LiDAR) sensor is used to jointly perceive the environment, and a multi-scale fusion scheme is employed to improve the accuracy of the disparity map. This solution not only has the advantages of dense perception of binocular stereo vision sensors but also considers the perception accuracy of LiDAR sensors. Experiments demonstrate that the multi-scale multi-sensor scheme proposed in this paper significantly improves disparity map estimation.

Fast measurement and prediction method for electromagnetic susceptibility of receiver
Yan CHEN, Zhonghao LU, Yunxia LIU
2024, 35(2):  275-285.  doi:10.23919/JSEE.2023.000127
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Aiming at evaluating and predicting rapidly and accurately a high sensitivity receiver’s adaptability in complex electromagnetic environments, a novel testing and prediction method based on dual-channel multi-frequency is proposed to improve the traditional two-tone test. Firstly, two signal generators are used to generate signals at the radio frequency (RF) by frequency scanning, and then a rapid measurement at the intermediate frequency (IF) output port is carried out to obtain a huge amount of sample data for the subsequent analysis. Secondly, the IF output response data are modeled and analyzed to construct the linear and nonlinear response constraint equations in the frequency domain and prediction models in the power domain, which provide the theoretical criteria for interpreting and predicting electromagnetic susceptibility (EMS) of the receiver. An experiment performed on a radar receiver confirms the reliability of the method proposed in this paper. It shows that the interference of each harmonic frequency and each order to the receiver can be identified and predicted with the sensitivity model. Based on this, fast and comprehensive evaluation and prediction of the receiver’s EMS in complex environment can be efficiently realized.

Efficient unequal error protection for online fountain codes
Pengcheng SHI, Zhenyong WANG, Dezhi LI, Haibo LYU
2024, 35(2):  286-293.  doi:10.23919/JSEE.2022.000156
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In this paper, an efficient unequal error protection (UEP) scheme for online fountain codes is proposed. In the build-up phase, the traversing-selection strategy is proposed to select the most important symbols (MIS). Then, in the completion phase, the weighted-selection strategy is applied to provide low overhead. The performance of the proposed scheme is analyzed and compared with the existing UEP online fountain scheme. Simulation results show that in terms of MIS and the least important symbols (LIS), when the bit error ratio is $ {10^{ - 4}} $, the proposed scheme can achieve $ 85{\text{% }} $ and $ 31.58{\text{% }} $ overhead reduction, respectively.

Sound event localization and detection based on deep learning
Dada ZHAO, Kai DING, Xiaogang QI, Yu CHEN, Hailin FENG
2024, 35(2):  294-301.  doi:10.23919/JSEE.2023.000110
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Acoustic source localization (ASL) and sound event detection (SED) are two widely pursued independent research fields. In recent years, in order to achieve a more complete spatial and temporal representation of sound field, sound event localization and detection (SELD) has become a very active research topic. This paper presents a deep learning-based multi-overlapping sound event localization and detection algorithm in three-dimensional space. Log-Mel spectrum and generalized cross-correlation spectrum are joined together in channel dimension as input features. These features are classified and regressed in parallel after training by a neural network to obtain sound recognition and localization results respectively. The channel attention mechanism is also introduced in the network to selectively enhance the features containing essential information and suppress the useless features. Finally, a thourough comparison confirms the efficiency and effectiveness of the proposed SELD algorithm. Field experiments show that the proposed algorithm is robust to reverberation and environment and can achieve higher recognition and localization accuracy compared with the baseline method.

Localization for mixed near-field and far-field sources under impulsive noise
Hongyuan GAO, Yuze ZHANG, Ya’nan DU, Jianhua CHENG, Menghan CHEN
2024, 35(2):  302-315.  doi:10.23919/JSEE.2023.000065
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In order to solve the problem that the performance of traditional localization methods for mixed near-field sources (NFSs) and far-field sources (FFSs) degrades under impulsive noise, a robust and novel localization method is proposed. After eliminating the impacts of impulsive noise by the weighted outlier filter, the direction of arrivals (DOAs) of FFSs can be estimated by multiple signal classification (MUSIC) spectral peaks search. Based on the DOAs information of FFSs, the separation of mixed sources can be performed. Finally, the estimation of localizing parameters of NFSs can avoid two-dimension spectral peaks search by decomposing steering vectors. The Cramer-Rao bounds (CRB) for the unbiased estimations of DOA and range under impulsive noise have been drawn. Simulation experiments verify that the proposed method has advantages in probability of successful estimation (PSE) and root mean square error (RMSE) compared with existing localization methods. It can be concluded that the proposed method is effective and reliable in the environment with low generalized signal to noise ratio (GSNR), few snapshots, and strong impulse.

Modulated-ISRJ rejection using online dictionary learning for synthetic aperture radar imagery
Shaopeng WEI, Lei ZHANG, Jingyue LU, Hongwei LIU
2024, 35(2):  316-329.  doi:10.23919/JSEE.2023.000076
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In electromagnetic countermeasures circumstances, synthetic aperture radar (SAR) imagery usually suffers from severe quality degradation from modulated interrupt sampling repeater jamming (MISRJ), which usually owes considerable coherence with the SAR transmission waveform together with periodical modulation patterns. This paper develops an MISRJ suppression algorithm for SAR imagery with online dictionary learning. In the algorithm, the jamming modulation temporal properties are exploited with extracting and sorting MISRJ slices using fast-time autocorrelation. Online dictionary learning is followed to separate real signals from jamming slices. Under the learned representation, time-varying MISRJs are suppressed effectively. Both simulated and real-measured SAR data are also used to confirm advantages in suppressing time-varying MISRJs over traditional methods.

An angular blinking jamming method based on electronically controlled corner reflectors
Lin GAN, Zehao WU, Xuesong WANG, Jianbing LI
2024, 35(2):  330-338.  doi:10.23919/JSEE.2023.000068
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Passive jamming is believed to have very good potential in countermeasure community. In this paper, a passive angular blinking jamming method based on electronically controlled corner reflectors is proposed. The amplitude of the incident wave can be modulated by switching the corner reflector between the penetration state and the reflection state, and the ensemble of multiple corner reflectors with towing rope can result in complex angle decoying effects. Dependency of the decoying effect on corner reflectors ’ radar cross section and positions are analyzed and simulated. Results show that the angle measured by a monopulse radar can be significantly interfered by this method while the automatic tracking is employed.

Coarse-fine joint target parameter estimation method based on AN-RSC in OFDM passive radar
Chujun WANG, Xianrong WAN, Jianxin YI, Feng CHENG
2024, 35(2):  339-349.  doi:10.23919/JSEE.2023.000100
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In this paper, we study the accuracy of delay-Doppler parameter estimation of targets in a passive radar using orthogonal frequency division multiplexing (OFDM) signal. A coarse-fine joint estimation method is proposed to achieve better estimation accuracy of target parameters without excessive computational burden. Firstly, the modulation symbol domain (MSD) method is used to roughly estimate the delay and Doppler of targets. Then, to obtain high-precision Doppler estimation, the atomic norm (AN) based on the multiple measurement vectors (MMV) model (MMV-AN) is used to manifest the signal sparsity in the continuous Doppler domain. At the same time, a reference signal compensation (RSC) method is presented to obtain high-precision delay estimation. Simulation results based on the OFDM signal show that the coarse-fine joint estimation method based on AN-RSC can obtain a more accurate estimation of target parameters compared with other algorithms. In addition, the proposed method also possesses computational advantages compared with the joint parameter estimation.

A target parameter estimation method via atom-reconstruction in radar mainlobe jamming
Bilei ZHOU, Weijian LIU, Rongfeng LI, Hui CHEN, Liang ZHANG, Qinglei DU, Binbin LI, Hao CHEN
2024, 35(2):  350-360.  doi:10.23919/JSEE.2024.000001
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Mainlobe jamming (MLJ) brings a big challenge for radar target detection, tracking, and identification. The suppression of MLJ is a hard task and an open problem in the electronic counter-counter measures (ECCM) field. Target parameters and target direction estimation is difficult in radar MLJ. A target parameter estimation method via atom-reconstruction in radar MLJ is proposed in this paper. The proposed method can suppress the MLJ and simultaneously provide high estimation accuracy of target range and angle. Precisely, the eigen-projection matrix processing (EMP) algorithm is adopted to suppress the MLJ, and the target range is estimated effectively through the beamforming and pulse compression. Then the target angle can be effectively estimated by the atom-reconstruction method. Without any prior knowledge, the MLJ can be canceled, and the angle estimation accuracy is well preserved. Furthermore, the proposed method does not have strict requirement for radar array construction, and it can be applied for linear array and planar array. Moreover, the proposed method can effectively estimate the target azimuth and elevation simultaneously when the target azimuth (or elevation) equals to the jamming azimuth (or elevation), because the MLJ is suppressed in spatial plane dimension.

Aerial target threat assessment based on gated recurrent unit and self-attention mechanism
Chen CHEN, Wei QUAN, Zhuang SHAO
2024, 35(2):  361-373.  doi:10.23919/JSEE.2023.000116
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Aerial threat assessment is a crucial link in modern air combat, whose result counts a great deal for commanders to make decisions. With the consideration that the existing threat assessment methods have difficulties in dealing with high dimensional time series target data, a threat assessment method based on self-attention mechanism and gated recurrent unit (SA-GRU) is proposed. Firstly, a threat feature system including air combat situations and capability features is established. Moreover, a data augmentation process based on fractional Fourier transform (FRFT) is applied to extract more valuable information from time series situation features. Furthermore, aiming to capture key characteristics of battlefield evolution, a bidirectional GRU and SA mechanisms are designed for enhanced features. Subsequently, after the concatenation of the processed air combat situation and capability features, the target threat level will be predicted by fully connected neural layers and the softmax classifier. Finally, in order to validate this model, an air combat dataset generated by a combat simulation system is introduced for model training and testing. The comparison experiments show the proposed model has structural rationality and can perform threat assessment faster and more accurately than the other existing models based on deep learning.

Real-time UAV path planning based on LSTM network
Jiandong ZHANG, Yukun GUO, Lihui ZHENG, Qiming YANG, Guoqing SHI, Yong WU
2024, 35(2):  374-385.  doi:10.23919/JSEE.2023.000157
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To address the shortcomings of single-step decision making in the existing deep reinforcement learning based unmanned aerial vehicle (UAV) real-time path planning problem, a real-time UAV path planning algorithm based on long short-term memory (RPP-LSTM) network is proposed, which combines the memory characteristics of recurrent neural network (RNN) and the deep reinforcement learning algorithm. LSTM networks are used in this algorithm as Q-value networks for the deep Q network (DQN) algorithm, which makes the decision of the Q-value network has some memory. Thanks to LSTM network, the Q-value network can use the previous environmental information and action information which effectively avoids the problem of single-step decision considering only the current environment. Besides, the algorithm proposes a hierarchical reward and punishment function for the specific problem of UAV real-time path planning, so that the UAV can more reasonably perform path planning. Simulation verification shows that compared with the traditional feed-forward neural network (FNN) based UAV autonomous path planning algorithm, the RPP-LSTM proposed in this paper can adapt to more complex environments and has significantly improved robustness and accuracy when performing UAV real-time path planning.

Operational requirements analysis method based on question answering of WEKG
Zhiwei ZHANG, Yajie DOU, Xiangqian XU, Yufeng MA, Jiang JIANG, Yuejin TAN
2024, 35(2):  386-395.  doi:10.23919/JSEE.2024.000004
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The weapon and equipment operational requirement analysis (WEORA) is a necessary condition to win a future war, among which the acquisition of knowledge about weapons and equipment is a great challenge. The main challenge is that the existing weapons and equipment data fails to carry out structured knowledge representation, and knowledge navigation based on natural language cannot efficiently support the WEORA. To solve above problem, this research proposes a method based on question answering (QA) of weapons and equipment knowledge graph (WEKG) to construct and navigate the knowledge related to weapons and equipment in the WEORA. This method firstly constructs the WEKG, and builds a neutral network-based QA system over the WEKG by means of semantic parsing for knowledge navigation. Finally, the method is evaluated and a chatbot on the QA system is developed for the WEORA. Our proposed method has good performance in the accuracy and efficiency of searching target knowledge, and can well assist the WEORA.

Classification of aviation incident causes using LGBM with improved cross-validation
Xiaomei NI, Huawei WANG, Lingzi CHEN, Ruiguan LIN
2024, 35(2):  396-405.  doi:10.23919/JSEE.2024.000035
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Aviation accidents are currently one of the leading causes of significant injuries and deaths worldwide. This entices researchers to investigate aircraft safety using data analysis approaches based on an advanced machine learning algorithm. To assess aviation safety and identify the causes of incidents, a classification model with light gradient boosting machine (LGBM) based on the aviation safety reporting system (ASRS) has been developed. It is improved by k-fold cross-validation with hybrid sampling model (HSCV), which may boost classification performance and maintain data balance. The results show that employing the LGBM-HSCV model can significantly improve accuracy while alleviating data imbalance. Vertical comparison with other cross-validation (CV) methods and lateral comparison with different fold times comprise the comparative approach. Aside from the comparison, two further CV approaches based on the improved method in this study are discussed: one with a different sampling and folding order, and the other with more CV. According to the assessment indices with different methods, the LGBM-HSCV model proposed here is effective at detecting incident causes. The improved model for imbalanced data categorization proposed may serve as a point of reference for similar data processing, and the model’s accurate identification of civil aviation incident causes can assist to improve civil aviation safety.

CBA: multi source fusion model for fast and intelligent target intention identification
Shichang WAN, Qingshan LI, Xuhua WANG, Nanhua LU
2024, 35(2):  406-416.  doi:10.23919/JSEE.2024.000023
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How to mine valuable information from massive multi-source heterogeneous data and identify the intention of aerial targets is a major research focus at present. Aiming at the long-term dependence of air target intention recognition, this paper deeply explores the potential attribute features from the spatiotemporal sequence data of the target. First, we build an intelligent dynamic intention recognition framework, including a series of specific processes such as data source, data preprocessing, target space-time, convolutional neural networks-bidirectional gated recurrent unit-atteneion (CBA) model and intention recognition. Then, we analyze and reason the designed CBA model in detail. Finally, through comparison and analysis with other recognition model experiments, our proposed method can effectively improve the accuracy of air target intention recognition, and is of significance to the commanders’ operational command and situation prediction.

Track correlation algorithm based on CNN-LSTM for swarm targets
Jinyang CHEN, Xuhua WANG, Xian CHEN
2024, 35(2):  417-429.  doi:10.23919/JSEE.2024.000033
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The rapid development of unmanned aerial vehicle (UAV) swarm, a new type of aerial threat target, has brought great pressure to the air defense early warning system. At present, most of the track correlation algorithms only use part of the target location, speed, and other information for correlation. In this paper, the artificial neural network method is used to establish the corresponding intelligent track correlation model and method according to the characteristics of swarm targets. Precisely, a route correlation method based on convolutional neural networks (CNN) and long short-term memory (LSTM) Neural network is designed. In this model, the CNN is used to extract the formation characteristics of UAV swarm and the spatial position characteristics of single UAV track in the formation, while the LSTM is used to extract the time characteristics of UAV swarm. Experimental results show that compared with the traditional algorithms, the algorithm based on CNN-LSTM neural network can make full use of multiple feature information of the target, and has better robustness and accuracy for swarm targets.

A framework of force of information influence and application for C4KISR system
Shaojie MAO, Lianwang DIAO, Yu SUN, Heng WANG, Kan YI, Xin XU, Xiaobin MAO, Kecheng ZHANG, Long SHENG
2024, 35(2):  430-443.  doi:10.23919/JSEE.2024.000011
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The subversive nature of information war lies not only in the information itself, but also in the circulation and application of information. It has always been a challenge to quantitatively analyze the function and effect of information flow through command, control, communications, computer, kill, intelligence, surveillance, reconnaissance (C4KISR) system. In this work, we propose a framework of force of information influence and the methods for calculating the force of information influence between C4KISR nodes of sensing, intelligence processing, decision making and fire attack. Specifically, the basic concept of force of information influence between nodes in C4KISR system is formally proposed and its mathematical definition is provided. Then, based on the information entropy theory, the model of force of information influence between C4KISR system nodes is constructed. Finally, the simulation experiments have been performed under an air defense and attack scenario. The experimental results show that, with the proposed force of information influence framework, we can effectively evaluate the contribution of information circulation through different C4KISR system nodes to the corresponding tasks. Our framework of force of information influence can also serve as an effective tool for the design and dynamic reconfiguration of C4KISR system architecture.

Adaptive admittance tracking control for interactive robot with prescribed performance
Qingrui MENG, Yan LIN
2024, 35(2):  444-450.  doi:10.23919/JSEE.2024.000038
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An adaptive control approach is presented in this paper for tracking desired trajectories in interactive manipulators. The controller design incorporates prescribed performance functions (PPFs) to improve dynamic performance. Notably, the performance of the output error is confined in an envelope characterized by exponential convergence, leading to convergence to zero. This feature ensures a prompt response from admittance control and establishes a reliable safety framework for interactions. Simulation results provide practical insights, demonstrating the viability of the control scheme proposed in this paper.

Time-varying parameters estimation with adaptive neural network EKF for missile-dual control system
Yuqi YUAN, Di ZHOU, Junlong LI, Chaofei LOU
2024, 35(2):  451-462.  doi:10.23919/JSEE.2024.000008
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In this paper, a filtering method is presented to estimate time-varying parameters of a missile dual control system with tail fins and reaction jets as control variables. In this method, the long-short-term memory (LSTM) neural network is nested into the extended Kalman filter (EKF) to modify the Kalman gain such that the filtering performance is improved in the presence of large model uncertainties. To avoid the unstable network output caused by the abrupt changes of system states, an adaptive correction factor is introduced to correct the network output online. In the process of training the network, a multi-gradient descent learning mode is proposed to better fit the internal state of the system, and a rolling training is used to implement an online prediction logic. Based on the Lyapunov second method, we discuss the stability of the system, the result shows that when the training error of neural network is sufficiently small, the system is asymptotically stable. With its application to the estimation of time-varying parameters of a missile dual control system, the LSTM-EKF shows better filtering performance than the EKF and adaptive EKF (AEKF) when there exist large uncertainties in the system model.

Distributed collaborative complete coverage path planning based on hybrid strategy
Jia ZHANG, Xin DU, Qichen DONG, Bin XIN
2024, 35(2):  463-472.  doi:10.23919/JSEE.2023.000118
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Collaborative coverage path planning (CCPP) refers to obtaining the shortest paths passing over all places except obstacles in a certain area or space. A multi-unmanned aerial vehicle (UAV) collaborative CCPP algorithm is proposed for the urban rescue search or military search in outdoor environment. Due to flexible control of small UAVs, it can be considered that all UAVs fly at the same altitude, that is, they perform search tasks on a two-dimensional plane. Based on the agents’ motion characteristics and environmental information, a mathematical model of CCPP problem is established. The minimum time for UAVs to complete the CCPP is the objective function, and complete coverage constraint, no-fly constraint, collision avoidance constraint, and communication constraint are considered. Four motion strategies and two communication strategies are designed. Then a distributed CCPP algorithm is designed based on hybrid strategies. Simulation results compared with pattern-based genetic algorithm (PBGA) and random search method show that the proposed method has stronger real-time performance and better scalability and can complete the complete CCPP task more efficiently and stably.

Manipulator tracking technology based on FSRUKF
Guoqing SHI, Boyan ZHANG, Jiandong ZHANG, Qiming YANG, Xiaofeng HUANG, Jianyao QUE, Junwei PU, Xiutang GENG
2024, 35(2):  473-484.  doi:10.23919/JSEE.2024.000009
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Aiming at the shortcoming that the traditional industrial manipulator using off-line programming cannot change along with the change of external environment, the key technologies such as machine vision and manipulator control are studied, and a complete manipulator vision tracking system is designed. Firstly, Denavit-Hartenberg (D-H) parameters method is used to construct the model of the manipulator and analyze the forward and inverse kinematics equations of the manipulator. At the same time, a binocular camera is used to obtain the three-dimensional position of the target. Secondly, in order to make the manipulator track the target more accurately, the fuzzy adaptive square root unscented Kalman filter (FSRUKF) is proposed to estimate the target state. Finally, the manipulator tracking system is built by using the position-based visual servo. The simulation experiments show that FSRUKF converges faster and with less error than the square root unscented Kalman filter (SRUKF), which meets the application requirements of the manipulator tracking system, and basically meets the application requirements of the manipulator tracking system in the practical experiments.

Improved spatio-temporal alignment measurement method for hull deformation
Dongsheng XU, Yuanjin YU, Xiaoli ZHANG, Xiafu PENG
2024, 35(2):  485-494.  doi:10.23919/JSEE.2023.000139
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In this paper, an improved spatio-temporal alignment measurement method is presented to address the inertial matching measurement of hull deformation under the coexistence of time delay and large misalignment angle. Large misalignment angle and time delay often occur simultaneously and bring great challenges to the accurate measurement of hull deformation in space and time. The proposed method utilizes coarse alignment with large misalignment angle and time delay estimation of inertial measurement unit modeling to establish a brand-new spatio-temporal aligned hull deformation measurement model. In addition, two-step loop control is designed to ensure the accurate description of dynamic deformation angle and static deformation angle by the time-space alignment method of hull deformation. The experiments illustrate that the proposed method can effectively measure the hull deformation angle when time delay and large misalignment angle coexist.

Fast solution to the free return orbit’s reachable domain of the manned lunar mission by deep neural network
Luyi YANG, Haiyang LI, Jin ZHANG, Yuehe ZHU
2024, 35(2):  495-508.  doi:10.23919/JSEE.2023.000117
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It is important to calculate the reachable domain (RD) of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly evaluated and calculated via the classification and regression neural networks. An efficient database-generation method is developed for obtaining eight types of free return orbits and then the RD is defined by the orbit’s inclination and right ascension of ascending node (RAAN) at the perilune. A classify neural network and a regression network are trained respectively. The former is built for classifying the type of the RD, and the latter is built for calculating the inclination and RAAN of the RD. The simulation results show that two neural networks are well trained. The classification model has an accuracy of more than 99% and the mean square error of the regression model is less than ${0.01^ \circ }$ on the test set. Moreover, a serial strategy is proposed to combine the two surrogate models and a recognition tool is built to evaluate whether a lunar site could be reached. The proposed deep learning method shows the superiority in computation efficiency compared with the traditional double two-body model.