为满足基于直扩体制的复合维度信息传输技术的工程化应用需求,针对多序列映射二维信息调制、多相关通道并行捕获和伪码跟踪过程进行理论分析的基础上,采用FPGA平台,对直扩体制复合维度信息传输信号的产生和接收关键功能电路进行设计和...为满足基于直扩体制的复合维度信息传输技术的工程化应用需求,针对多序列映射二维信息调制、多相关通道并行捕获和伪码跟踪过程进行理论分析的基础上,采用FPGA平台,对直扩体制复合维度信息传输信号的产生和接收关键功能电路进行设计和仿真实现。仿真结果证明设计实现的多序列映射二维信息调制模块可实现复合维度信息传输信号的产生功能,多相关通道并行捕获模块可实现对伪随机序列的正确捕获,跟踪模块可实现正确的伪码跟踪,极大提高了复合维度直接序列扩频技术的工程化水平,为复合维度直扩技术提供实践基础,具有较强的实际应用价值。This study aims to advance multidimensional information transmission technology using direct sequence spread spectrum for real-world engineering applications. This paper offers an in-depth theoretical analysis of multi-sequence mapping, two-dimensional information modulation, parallel acquisition of correlated channels, and pseudocode tracking. The project centers on designing and simulating key circuits for generating and receiving multidimensional transmission signals using a field-programmable gate array (FPGA) platform. Simulation results show that the multi-sequence mapping and two-dimensional modulation module effectively produces multidimensional transmission signals. Furthermore, the parallel acquisition module for multiple correlated channels accurately captures pseudo-random sequences, and the tracking module successfully performs pseudocode tracking. These advancements greatly improve the engineering capabilities of composite dimension direct sequence spread spectrum technology, offering a strong foundation and substantial practical value.展开更多
针对满足低信噪比下信息可靠传输需求的问题,本文提出了一种基于优化遗传算法CA-GA的polar码构造方法。将polar码的信息子信道选择映射成N维二进制向量的优化问题,首先通过先验知识生成初始种群,再将贪婪算法引入选择过程中,然后在变异...针对满足低信噪比下信息可靠传输需求的问题,本文提出了一种基于优化遗传算法CA-GA的polar码构造方法。将polar码的信息子信道选择映射成N维二进制向量的优化问题,首先通过先验知识生成初始种群,再将贪婪算法引入选择过程中,然后在变异过程中引入柯西变异算子,最后根据种群适应度值自适应计算变异概率和交叉概率。进一步,以最小化误码率为目标,更新迭代生成适应度较高的种群,选取当前种群中最优秀的个体作为信息子信道索引向量,通过子信道索引向量、码长、码率以及信息位构造polar码。仿真结果表明,本文提出算法随着码长增加具有更低的误块率,在码长256、误块率为10−2时与GA构造法、蒙特卡洛构造法相比分别具有0.4 dB、0.5 dB的净增益,与传统遗传算法构造法相比约有0.05 dB的净增益,在码长512、误块率为10−2时和巴氏参数法、GA构造法、蒙特卡洛构造法相比分别具有0.5 dB、0.1 dB、0.15 dB的净增益。To meet the requirement of reliable information transmission under low signal-to-noise ratio, this paper proposes a polar code construction method based on an optimized genetic algorithm. The optimization problem of mapping the information sub-channel selection of polar codes into N-dimensional binary vectors involves first generating an initial population through prior knowledge, then introducing a greedy algorithm into the selection process, and finally introducing the Cauchy mutation operator in the mutation process. Finally, the mutation probability and crossover probability are adaptively calculated based on the population fitness value. Furthermore, with the goal of minimizing the bit error rate, the population with higher fitness is iteratively generated and updated. The best individual in the current population is selected as the information subchannel index vector. Using this subchannel index vector, along with the code length, code rate, and information bits, the polar code is constructed. The simulation results demonstrate that the algorithm proposed in this paper exhibits a lower block error rate as the code length increases. When the code length is 256 and the block error rate is 10−2, it achieves a net gain of 0.4 dB and 0.5 dB compared to the Genetic Algorithm (GA) construction method and Monte Carlo construction method, respectively, and approximately 0.05 dB compared to the traditional Genetic Algorithm construction method. For a code length of 512 and a block error rate of 10−2, it offers net gains of 0.5 dB, 0.1 dB, and 0.15 dB over the Bhattacharyya parameter method, GA construction method, and Monte Carlo construction method, respectively.展开更多
为解决前向连续均值去除算法实现复杂度较高、实时性不足的问题,在深入分析传统干扰检测算法基础上,提出基于四分位距的干扰检测算法,引入四分位距对均值最小分组频谱进行检测,抽取到尽可能接近底噪的水平均值计算判决门限值,解决了传统...为解决前向连续均值去除算法实现复杂度较高、实时性不足的问题,在深入分析传统干扰检测算法基础上,提出基于四分位距的干扰检测算法,引入四分位距对均值最小分组频谱进行检测,抽取到尽可能接近底噪的水平均值计算判决门限值,解决了传统FCME算法需要多次迭代的问题,提高处理效率。仿真结果表明,提出的算法底噪估计值与理论值最大偏差优于FCME算法,使用的排序次数更少,在多个干扰信号存在条件下具有较低的误码率。In order to solve the problem of high complexity and poor real-time performance of the forward continuous mean removal algorithm (FCME), an interference detection algorithm based on the interquartile range is proposed. By analyzing the principle of the traditional interference detection algorithms, the interquartile range was used to detect the minimum mean packet spectrum of the sampled signal. Then the judgment threshold as close as possible to the mean of the background noise is computed. Because the sorting process is removed, the efficiency of the algorithm is improved. The simulation results show that the maximum deviation between the estimated noise floor value and the theoretical value of the proposed algorithm is better than the maximum deviation of the FCME algorithm. The error rate is low under multiple interference signal conditions.展开更多
文摘为满足基于直扩体制的复合维度信息传输技术的工程化应用需求,针对多序列映射二维信息调制、多相关通道并行捕获和伪码跟踪过程进行理论分析的基础上,采用FPGA平台,对直扩体制复合维度信息传输信号的产生和接收关键功能电路进行设计和仿真实现。仿真结果证明设计实现的多序列映射二维信息调制模块可实现复合维度信息传输信号的产生功能,多相关通道并行捕获模块可实现对伪随机序列的正确捕获,跟踪模块可实现正确的伪码跟踪,极大提高了复合维度直接序列扩频技术的工程化水平,为复合维度直扩技术提供实践基础,具有较强的实际应用价值。This study aims to advance multidimensional information transmission technology using direct sequence spread spectrum for real-world engineering applications. This paper offers an in-depth theoretical analysis of multi-sequence mapping, two-dimensional information modulation, parallel acquisition of correlated channels, and pseudocode tracking. The project centers on designing and simulating key circuits for generating and receiving multidimensional transmission signals using a field-programmable gate array (FPGA) platform. Simulation results show that the multi-sequence mapping and two-dimensional modulation module effectively produces multidimensional transmission signals. Furthermore, the parallel acquisition module for multiple correlated channels accurately captures pseudo-random sequences, and the tracking module successfully performs pseudocode tracking. These advancements greatly improve the engineering capabilities of composite dimension direct sequence spread spectrum technology, offering a strong foundation and substantial practical value.
文摘针对满足低信噪比下信息可靠传输需求的问题,本文提出了一种基于优化遗传算法CA-GA的polar码构造方法。将polar码的信息子信道选择映射成N维二进制向量的优化问题,首先通过先验知识生成初始种群,再将贪婪算法引入选择过程中,然后在变异过程中引入柯西变异算子,最后根据种群适应度值自适应计算变异概率和交叉概率。进一步,以最小化误码率为目标,更新迭代生成适应度较高的种群,选取当前种群中最优秀的个体作为信息子信道索引向量,通过子信道索引向量、码长、码率以及信息位构造polar码。仿真结果表明,本文提出算法随着码长增加具有更低的误块率,在码长256、误块率为10−2时与GA构造法、蒙特卡洛构造法相比分别具有0.4 dB、0.5 dB的净增益,与传统遗传算法构造法相比约有0.05 dB的净增益,在码长512、误块率为10−2时和巴氏参数法、GA构造法、蒙特卡洛构造法相比分别具有0.5 dB、0.1 dB、0.15 dB的净增益。To meet the requirement of reliable information transmission under low signal-to-noise ratio, this paper proposes a polar code construction method based on an optimized genetic algorithm. The optimization problem of mapping the information sub-channel selection of polar codes into N-dimensional binary vectors involves first generating an initial population through prior knowledge, then introducing a greedy algorithm into the selection process, and finally introducing the Cauchy mutation operator in the mutation process. Finally, the mutation probability and crossover probability are adaptively calculated based on the population fitness value. Furthermore, with the goal of minimizing the bit error rate, the population with higher fitness is iteratively generated and updated. The best individual in the current population is selected as the information subchannel index vector. Using this subchannel index vector, along with the code length, code rate, and information bits, the polar code is constructed. The simulation results demonstrate that the algorithm proposed in this paper exhibits a lower block error rate as the code length increases. When the code length is 256 and the block error rate is 10−2, it achieves a net gain of 0.4 dB and 0.5 dB compared to the Genetic Algorithm (GA) construction method and Monte Carlo construction method, respectively, and approximately 0.05 dB compared to the traditional Genetic Algorithm construction method. For a code length of 512 and a block error rate of 10−2, it offers net gains of 0.5 dB, 0.1 dB, and 0.15 dB over the Bhattacharyya parameter method, GA construction method, and Monte Carlo construction method, respectively.
文摘为解决前向连续均值去除算法实现复杂度较高、实时性不足的问题,在深入分析传统干扰检测算法基础上,提出基于四分位距的干扰检测算法,引入四分位距对均值最小分组频谱进行检测,抽取到尽可能接近底噪的水平均值计算判决门限值,解决了传统FCME算法需要多次迭代的问题,提高处理效率。仿真结果表明,提出的算法底噪估计值与理论值最大偏差优于FCME算法,使用的排序次数更少,在多个干扰信号存在条件下具有较低的误码率。In order to solve the problem of high complexity and poor real-time performance of the forward continuous mean removal algorithm (FCME), an interference detection algorithm based on the interquartile range is proposed. By analyzing the principle of the traditional interference detection algorithms, the interquartile range was used to detect the minimum mean packet spectrum of the sampled signal. Then the judgment threshold as close as possible to the mean of the background noise is computed. Because the sorting process is removed, the efficiency of the algorithm is improved. The simulation results show that the maximum deviation between the estimated noise floor value and the theoretical value of the proposed algorithm is better than the maximum deviation of the FCME algorithm. The error rate is low under multiple interference signal conditions.
