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Functional Verification Based on FPGA for AVS Video Decoder 被引量:1
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作者 FU Fang-fang YI Oing-ming SHI Min 《Semiconductor Photonics and Technology》 CAS 2009年第4期219-224,共6页
In this paper,based on the field-programmable gate array(FPGA)xc5vlx220 of Xilinx Company,the FPGA verification method for application specific integrated circuit(ASIC)design is introduced.Firstly,the basic principles... In this paper,based on the field-programmable gate array(FPGA)xc5vlx220 of Xilinx Company,the FPGA verification method for application specific integrated circuit(ASIC)design is introduced.Firstly,the basic principles of FPGA verification are introduced.Then,the structure of the FPGA board and the verification methods are illustrated.Finally,the workflow of FPGA verification for audio video coding standard(AVS)decoder and the method of restoring images are introduced in detail.The FPGA resources occupancy is shown and analyzed.The result shows that FPGA can verify the ASIC rapidly and effectively so as to shorten the development cycle. 展开更多
关键词 fpga verification AVS video decoder MATLAB
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Research and Design of MP3 Player Decoder based on FPGA
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作者 Hang Xu 《International Journal of Technology Management》 2013年第1期121-123,共3页
The paper takes a method of a low speed processer based on FPGA hardware accelerator SOC units to realize the MP3 player, and include some peripheral devices. The experimental results show that the system has implemen... The paper takes a method of a low speed processer based on FPGA hardware accelerator SOC units to realize the MP3 player, and include some peripheral devices. The experimental results show that the system has implemented the basic functions of the MP3 player, having its own advantages on increasing the decoding speed and reducing the system consumption. The system is convenient to redesign for more function in the future. In conclusion, it has a wide application prospect. 展开更多
关键词 Mp3 player decoder fpga Huffman decoding principle
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Implementation of encoder and decoder for LDPC codes based on FPGA 被引量:7
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作者 CHENG Kun SHEN Qi +1 位作者 LIAO Shengkai PENG Chengzhi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第4期642-650,共9页
This paper proposes a parallel cyclic shift structure of address decoder to realize a high-throughput encoding and decoding method for irregular-quasi-cyclic low-density parity-check(IR-QC-LDPC)codes,with a dual-diago... This paper proposes a parallel cyclic shift structure of address decoder to realize a high-throughput encoding and decoding method for irregular-quasi-cyclic low-density parity-check(IR-QC-LDPC)codes,with a dual-diagonal parity structure.A normalized min-sum algorithm(NMSA)is employed for decoding.The whole verification of the encoding and decoding algorithm is simulated with Matlab,and the code rates of 5/6 and 2/3 are selected respectively for the initial bit error ratio as 6%and 1.04%.Based on the results of simulation,multi-code rates are compatible with different basis matrices.Then the simulated algorithms of encoder and decoder are migrated and implemented on the field programmable gate array(FPGA).The 183.36 Mbps throughput of encoder and the average 27.85 Mbps decoding throughput with the initial bit error ratio 6%are realized based on FPGA. 展开更多
关键词 LOW-DENSITY parity-check(LDPC) field programmable gate array(fpga) normalized min-sum algorithm(NMSA).
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An FPGA-based LDPC decoder with optimized scale factor of NMS decoding algorithm
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作者 LI Jinming ZHAGN Pingping +1 位作者 WANG Lanzhu WANG Guodong 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2022年第4期398-406,共9页
Considering that the hardware implementation of the normalized minimum sum(NMS)decoding algorithm for low-density parity-check(LDPC)code is difficult due to the uncertainty of scale factor,an NMS decoding algorithm wi... Considering that the hardware implementation of the normalized minimum sum(NMS)decoding algorithm for low-density parity-check(LDPC)code is difficult due to the uncertainty of scale factor,an NMS decoding algorithm with variable scale factor is proposed for the near-earth space LDPC codes(8177,7154)in the consultative committee for space data systems(CCSDS)standard.The shift characteristics of field programmable gate array(FPGA)is used to optimize the quantization data of check nodes,and finally the function of LDPC decoder is realized.The simulation and experimental results show that the designed FPGA-based LDPC decoder adopts the scaling factor in the NMS decoding algorithm to improve the decoding performance,simplify the hardware structure,accelerate the convergence speed and improve the error correction ability. 展开更多
关键词 LDPC code NMS decoding algorithm variable scale factor QUANTIZATION
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Design of improved error-rate sliding window decoder for SC-LDPC codes: reliable termination and channel value reuse
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作者 JIA Xishan LI Jining +3 位作者 YAO Yuan WANG Yifan LIU Bo XU Degang 《Optoelectronics Letters》 2025年第4期212-217,共6页
In this paper,an improved error-rate sliding window decoder is proposed for spatially coupled low-density parity-check(SC-LDPC)codes.For the conventional sliding window decoder,the message retention mechanism causes u... In this paper,an improved error-rate sliding window decoder is proposed for spatially coupled low-density parity-check(SC-LDPC)codes.For the conventional sliding window decoder,the message retention mechanism causes unreliable messages along the edges of belief propagation(BP)decoding in the current window to be kept for subsequent window decoding.To improve the reliability of the retained messages during the window transition,a reliable termination method is embedded,where the retained messages undergo more reliable parity checks.Additionally,decoding failure is unavoidable and even causes error propagation when the number of errors exceeds the error-correcting capability of the window.To mitigate this problem,a channel value reuse mechanism is designed,where the received channel values are utilized to reinitialize the window.Furthermore,considering the complexity and performance of decoding,a feasible sliding optimized window decoding(SOWD)scheme is introduced.Finally,simulation results confirm the superior performance of the proposed SOWD scheme in both the waterfall and error floor regions.This work has great potential in the applications of wireless optical communication and fiber optic communication. 展开更多
关键词 reliable termination message retention mechanism reliable termination method sliding window decoderthe error rate sliding window decoder belief propagation bp decoding retained messages
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FPGA Design and Implementation of a Convolutional Encoder and a Viterbi Decoder Based on 802.11a for OFDM
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作者 Yan Sun Zhizhong Ding 《Wireless Engineering and Technology》 2012年第3期125-131,共7页
In this paper, a modified FPGA scheme for the convolutional encoder and Viterbi decoder based on the IEEE 802.11a standards of WLAN is presented in OFDM baseband processing systems. The proposed design supports a gene... In this paper, a modified FPGA scheme for the convolutional encoder and Viterbi decoder based on the IEEE 802.11a standards of WLAN is presented in OFDM baseband processing systems. The proposed design supports a generic, robust and configurable Viterbi decoder with constraint length of 7, code rate of 1/2 and decoding depth of 36 symbols. The Viterbi decoder uses full-parallel structure to improve computational speed for the add-compare-select (ACS) modules, adopts optimal data storage mechanism to avoid overflow and employs three distributed RAM blocks to complete cyclic trace-back. It includes the core parts, for example, the state path measure computation, the preservation and transfer of the survivor path and trace-back decoding, etc. Compared to the general Viterbi decoder, this design can effectively decrease the 10% of chip logic elements, reduce 5% of power consumption, and increase the encoder and decoder working performance in the hardware implementation. Lastly, relevant simulation results using Verilog HDL language are verified based on a Xinlinx Virtex-II FPGA by ISE 7.1i. It is shown that the Viterbi decoder is capable of decoding (2, 1, 7) convolutional codes accurately with a throughput of 80 Mbps. 展开更多
关键词 fpga Convolutional ENCODER VITERBI decoder IEEE 802.11a OFDM
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Low power Viterbi decoder design for low altitude adhoc networks
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作者 FEI Yingying XIAO Chunlu +3 位作者 JING Wenhao MA Tianming WANG Jiahan JIN Jie 《High Technology Letters》 2025年第2期154-163,共10页
With the rapid development of low altitude economic industry,low altitude adhoc network technology has been getting more and more intensive attention.In the adhoc network protocol designed in this paper,the convolutio... With the rapid development of low altitude economic industry,low altitude adhoc network technology has been getting more and more intensive attention.In the adhoc network protocol designed in this paper,the convolutional code used is(3,1,7),and the design of a low power Viterbi decoder adapted to multi-rate variations is proposed.In the traditional Viterbi decoding method,the high complexity of path metric(PM)accumulation and Euclidean distance computation leads to the problems of low efficiency and large storage resources in the decoder.In this paper,an improved add compare select(ACS)algorithm,a generalized formula for branch metric(BM)based on Manhattan distance,and a method to reduce the accumulated PM for different Viterbi decoders are put forward.A simulation environment based on Vivado and Matlab to verify the accuracy and effectiveness of the proposed Viterbi decoder is also established.The experimental results show that the total power consumption is reduced by 15.58%while the decoding accuracy of the Viterbi decoder is guaranteed,which meets the design requirements of a low power Viterbi decoder. 展开更多
关键词 low altitude adhoc network Manhattan distance network protocol Viterbi decoder field programmable gate array(fpga)
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Anti-Interference High-Speed Modulation Decoder for Quantum Key Distribution
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作者 Hua-Xing Xu Shao-Hua Wang +1 位作者 Chang-Lei Wang Ping Zhang 《Chinese Physics Letters》 2025年第1期34-39,共6页
Quantum key distribution is increasingly transitioning toward network applications,necessitating advancements in system performance,including photonic integration for compact designs,enhanced stability against environ... Quantum key distribution is increasingly transitioning toward network applications,necessitating advancements in system performance,including photonic integration for compact designs,enhanced stability against environmental disturbances,higher key rates,and improved efficiency.In this letter,we propose an orthogonal polarization exchange reflector Michelson interferometer model to address quantum channel disturbances caused by environmental factors.Based on this model,we designed a Sagnac reflector-Michelson interferometer decoder and verified its performance through an interference system.The interference fringe visibility exceeded 98%across all four coding phases at 625 MHz.These results indicate that the decoder effectively mitigates environmental interference while supporting high-speed modulation frequencies.In addition,the proposed anti-interference decoder,which does not rely on magneto-optical devices,is well-suited for photonic integration,aligning with the development trajectory for next-generation quantum communication devices. 展开更多
关键词 decoder INTERFEROMETER POLARIZATION
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基于SoC FPGA的机载相机转角控制系统设计
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作者 柯曦宸 史艳高 《现代信息科技》 2025年第21期30-33,共4页
针对无人机在河流边坡巡检过程中需远程调节机载相机拍摄角度的需求,设计并实现了一种基于SoC FPGA架构的机载相机转角控制系统。该系统以FPGA内部构建的RISC-V处理器为控制核心,通过陀螺仪传感器与无线模块采集数据并发送控制指令,并采... 针对无人机在河流边坡巡检过程中需远程调节机载相机拍摄角度的需求,设计并实现了一种基于SoC FPGA架构的机载相机转角控制系统。该系统以FPGA内部构建的RISC-V处理器为控制核心,通过陀螺仪传感器与无线模块采集数据并发送控制指令,并采用PID算法实现角度的动态调节与精确控制。最后通过实验对系统进行原型验证,测试结果表明,该系统能够稳定、实时地完成姿态数据采集、无线数据收发及转角控制闭环执行,满足无人机机载相机的转角控制需求。 展开更多
关键词 SoC fpga RISC-V处理器 姿态控制 无人机巡检 PID控制
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基于自注意力机制说话人编码器与SA-Decoder的语音克隆方法
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作者 焦乐岩 朱欣娟 《计算机与现代化》 2025年第7期69-76,共8页
FreeVC模型在语音克隆技术领域表现出色。但是由于语音序列中包含复杂的语音特征变化和信息,例如音色、风格等,FreeVC模型中的Speaker Encoder模块只使用单一的LSTM网络难以准确地提取和表示说话人信息,这会导致模型处理语音序列的性能... FreeVC模型在语音克隆技术领域表现出色。但是由于语音序列中包含复杂的语音特征变化和信息,例如音色、风格等,FreeVC模型中的Speaker Encoder模块只使用单一的LSTM网络难以准确地提取和表示说话人信息,这会导致模型处理语音序列的性能下降,影响声音转换质量和准确性。并且FreeVC模型使用传统的解码器,其中上采样(反卷积)操作细节丢失,导致重建还原的音频咬字细节会模糊不清,从而产生音频伪影。针对这些问题,本文提出一种基于自注意力机制的说话人编码器与SA-Decoder的语音克隆方法FreeVC-SA。该方法将说话人的梅尔谱作为输入,在LSTM网络上加入自注意力机制有助于模型更好地捕捉长距离依赖关系,更为准确地提取说话人的音色、风格等特征。使用SA-Decoder可以很好地解决局部感受野限制问题,使得重建生成的语音克隆效果更加真实、清晰。实验结果表明,与所有基线模型相比,FreeVC-SA语音克隆的自然度相似性和情感相似性均有明显提升,字错误率和字符错误率均有明显下降。 展开更多
关键词 语音克隆 说话人编码器 SA-decoder 自注意力机制 FreeVC-SA
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Global receptive field transformer decoder method on quantum surface code data and syndrome error correction
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作者 Ao-Qing Li Ce-Wen Tian +2 位作者 Xiao-Xuan Xu Hong-Yang Ma Jun-Qing Liang 《Chinese Physics B》 2025年第3期267-276,共10页
Quantum computing has the potential to solve complex problems that are inefficiently handled by classical computation.However,the high sensitivity of qubits to environmental interference and the high error rates in cu... Quantum computing has the potential to solve complex problems that are inefficiently handled by classical computation.However,the high sensitivity of qubits to environmental interference and the high error rates in current quantum devices exceed the error correction thresholds required for effective algorithm execution.Therefore,quantum error correction technology is crucial to achieving reliable quantum computing.In this work,we study a topological surface code with a two-dimensional lattice structure that protects quantum information by introducing redundancy across multiple qubits and using syndrome qubits to detect and correct errors.However,errors can occur not only in data qubits but also in syndrome qubits,and different types of errors may generate the same syndromes,complicating the decoding task and creating a need for more efficient decoding methods.To address this challenge,we used a transformer decoder based on an attention mechanism.By mapping the surface code lattice,the decoder performs a self-attention process on all input syndromes,thereby obtaining a global receptive field.The performance of the decoder was evaluated under a phenomenological error model.Numerical results demonstrate that the decoder achieved a decoding accuracy of 93.8%.Additionally,we obtained decoding thresholds of 5%and 6.05%at maximum code distances of 7 and 9,respectively.These results indicate that the decoder used demonstrates a certain capability in correcting noise errors in surface codes. 展开更多
关键词 quantum error correction surface code transformer decoder
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Pyramid–MixNet: Integrate Attention into Encoder-Decoder Transformer Framework for Automatic Railway Surface Damage Segmentation
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作者 Hui Luo Wenqing Li Wei Zeng 《Computers, Materials & Continua》 2025年第7期1567-1580,共14页
Rail surface damage is a critical component of high-speed railway infrastructure,directly affecting train operational stability and safety.Existing methods face limitations in accuracy and speed for small-sample,multi... Rail surface damage is a critical component of high-speed railway infrastructure,directly affecting train operational stability and safety.Existing methods face limitations in accuracy and speed for small-sample,multi-category,and multi-scale target segmentation tasks.To address these challenges,this paper proposes Pyramid-MixNet,an intelligent segmentation model for high-speed rail surface damage,leveraging dataset construction and expansion alongside a feature pyramid-based encoder-decoder network with multi-attention mechanisms.The encoding net-work integrates Spatial Reduction Masked Multi-Head Attention(SRMMHA)to enhance global feature extraction while reducing trainable parameters.The decoding network incorporates Mix-Attention(MA),enabling multi-scale structural understanding and cross-scale token group correlation learning.Experimental results demonstrate that the proposed method achieves 62.17%average segmentation accuracy,80.28%Damage Dice Coefficient,and 56.83 FPS,meeting real-time detection requirements.The model’s high accuracy and scene adaptability significantly improve the detection of small-scale and complex multi-scale rail damage,offering practical value for real-time monitoring in high-speed railway maintenance systems. 展开更多
关键词 Pyramid vision transformer encoder–decoder architecture railway damage segmentation masked multi-head attention mix-attention
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28 nm SRAM型SoC FPGA的电离总剂量效应
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作者 黄开 李豫东 +3 位作者 冯婕 施炜雷 文林 郭旗 《微电子学》 北大核心 2025年第5期889-894,共6页
对一款商用Zynq-7000型芯片进行了60Coγ辐照试验和退火试验,研究了28 nm静态随机存取存储器(Static Random-Access Memory,SRAM)型现代片上系统(System on Chip,SoC)现场可编程门阵列(Field-Programmable Gate Array,FPGA)的电离总剂量... 对一款商用Zynq-7000型芯片进行了60Coγ辐照试验和退火试验,研究了28 nm静态随机存取存储器(Static Random-Access Memory,SRAM)型现代片上系统(System on Chip,SoC)现场可编程门阵列(Field-Programmable Gate Array,FPGA)的电离总剂量(Total Ionizing Dose,TID)辐射损伤。优化了商用开发板重新设计了外围电路以提高屏蔽效果。试验结果表明,随着累积剂量的增加,功耗电流增加,输出高电平下降,累积剂量到2700 Gy(Si)时,锁相环输出波形变成直线,所有的程序功能突然失效,其上电复位电路异常导致功能失效。室温退火后上述参数部分恢复,Zynq-7000芯片功能恢复。由FPGA实现的环形振荡器物理不可克隆函数(Ring Oscillator Physical Unclonable Function,RO-PUF)的可靠性随累积剂量增加而下降,其基本单元查找表发生退化。 展开更多
关键词 fpga 电离总剂量辐射 SOC 环形振荡器物理不可克隆函数
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Area optimization of parallel Chien search architecture for Reed-Solomon(255,239) decoder 被引量:1
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作者 胡庆生 王志功 +1 位作者 张军 肖洁 《Journal of Southeast University(English Edition)》 EI CAS 2006年第1期5-10,共6页
A global optimization algorithm (GOA) for parallel Chien search circuit in Reed-Solomon (RS) (255,239) decoder is presented. By finding out the common modulo 2 additions within groups of Galois field (GF) mult... A global optimization algorithm (GOA) for parallel Chien search circuit in Reed-Solomon (RS) (255,239) decoder is presented. By finding out the common modulo 2 additions within groups of Galois field (GF) multipliers and pre-computing the common items, the GOA can reduce the number of XOR gates efficiently and thus reduce the circuit area. Different from other local optimization algorithms, the GOA is a global one. When there are more than one maximum matches at a time, the best match choice in the GOA has the least impact on the final result by only choosing the pair with the smallest relational value instead of choosing a pair randomly. The results show that the area of parallel Chien search circuits can be reduced by 51% compared to the direct implementation when the group-based GOA is used for GF multipliers and by 26% if applying the GOA to GF multipliers separately. This optimization scheme can be widely used in general parallel architecture in which many GF multipliers are involved. 展开更多
关键词 RS decoder Chien search circuit area optimization Galois field multiplier
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An AND-LUT Based Hybrid FPGA Architecture 被引量:1
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作者 陈利光 来金梅 童家榕 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第3期398-403,共6页
A new hybrid FPGA architecture is proposed. The logic tile,which consists of a logic cluster and related connection boxes (CBs), can be configured as either programmable logic arrays (PLAs) or look-up tables (LUT... A new hybrid FPGA architecture is proposed. The logic tile,which consists of a logic cluster and related connection boxes (CBs), can be configured as either programmable logic arrays (PLAs) or look-up tables (LUTs), This architecture can be classified as an AND-LUT array. PLAs are suitable for the implementation of high fan-in logic circuits, while LUTs are used to implement low fan-in logic circuits. As a result, the proposed hybrid FPGA architecture (HFA) is more flexible to improve logic density. Experiments based on MCNC benchmark circuits were performed in both the hybrid architecture and conventional LUT-based symmetrical FPGA architecture in term of area consumption. Preliminary results indicate that on average, the area is reduced by 46% using the new hybrid architecture. 展开更多
关键词 hybrid fpga AND-LUT array AND-OR array PLA LUT
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基于芯粒的Flash FPGA驱动测试技术
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作者 黄健 王雪萍 +1 位作者 陈诚 陈龙 《电子技术应用》 2025年第5期1-4,共4页
针对基于芯粒的Flash FPGA驱动覆盖率测试,利用Flash FPGA的系统控制寄存器与边界扫描寄存器模块,配置FPGA不同的驱动模式,并通过传统的单芯片Flash单元配置进行对比验证。实验结果表明,基于芯粒的Flash FPGA控制寄存器配置的驱动性能... 针对基于芯粒的Flash FPGA驱动覆盖率测试,利用Flash FPGA的系统控制寄存器与边界扫描寄存器模块,配置FPGA不同的驱动模式,并通过传统的单芯片Flash单元配置进行对比验证。实验结果表明,基于芯粒的Flash FPGA控制寄存器配置的驱动性能与传统的单芯片Flash单元配置一致,测试时间缩短到1/3。 展开更多
关键词 芯粒 现场可编程门阵列 主控寄存器 驱动性能
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An Improved LZO Compression Algorithm for FPGA Configuration Bitstream Files
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作者 Xiaoling Lai Jian Zhang +3 位作者 Yangming Guo Ting Ju Qi Zhu Guochang Zhou 《Computers, Materials & Continua》 2025年第2期3091-3109,共19页
With the increase in the quantity and scale of Static Random-Access Memory Field Programmable Gate Arrays (SRAM-based FPGAs) for aerospace application, the volume of FPGA configuration bit files that must be stored ha... With the increase in the quantity and scale of Static Random-Access Memory Field Programmable Gate Arrays (SRAM-based FPGAs) for aerospace application, the volume of FPGA configuration bit files that must be stored has increased dramatically. The use of compression techniques for these bitstream files is emerging as a key strategy to alleviate the burden on storage resources. Due to the severe resource constraints of space-based electronics and the unique application environment, the simplicity, efficiency and robustness of the decompression circuitry is also a key design consideration. Through comparative analysis current bitstream file compression technologies, this research suggests that the Lempel Ziv Oberhumer (LZO) compression algorithm is more suitable for satellite applications. This paper also delves into the compression process and format of the LZO compression algorithm, as well as the inherent characteristics of configuration bitstream files. We propose an improved algorithm based on LZO for bitstream file compression, which optimises the compression process by refining the format and reducing the offset. Furthermore, a low-cost, robust decompression hardware architecture is proposed based on this method. Experimental results show that the compression speed of the improved LZO algorithm is increased by 3%, the decompression hardware cost is reduced by approximately 60%, and the compression ratio is slightly reduced by 0.47%. 展开更多
关键词 fpga configuration bitstream file LZO compression DECOMPRESSION
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A Total Dose Radiation Hardened PDSOI CMOS 3-Line to 8-Line Decoder
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作者 刘梦新 韩郑生 +3 位作者 李多力 刘刚 赵超荣 赵发展 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第6期1036-1039,共4页
The first domestic total dose hardened 2μm partially depleted silicon-on-insulator (PDSOI) CMOS 3-line to 8- line decoder fabricated in SIMOX is demonstrated. The radiation performance is characterized by transisto... The first domestic total dose hardened 2μm partially depleted silicon-on-insulator (PDSOI) CMOS 3-line to 8- line decoder fabricated in SIMOX is demonstrated. The radiation performance is characterized by transistor threshold voltage shifts,circuit static leakage currents,and I-V curves as a function of total dose up to 3× 10^5rad(Si). The worst case threshold voltage shifts of the front channels are less than 20mV for nMOS transistors at 3 × 10^5rad(Si) and follow-up irradiation and less than 70mV for the pMOS transistors. Furthermore, no significant radiation induced leakage currents and functional degeneration are observed. 展开更多
关键词 PDSOI decoder total dose RADIATION
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Research onπ/4QPSK Modulation Communication Transmission System and FPGA Implementation
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作者 Yuhui Chu Yunjie Yuan +2 位作者 Xiaolei Cai Yanyan Wang Peijie Yin 《Journal of Electronic Research and Application》 2025年第2期12-17,共6页
This paper examines theπ/4QPSK modulation communication transmission system,analyzing the performance advantages and disadvantages ofπ/4QPSK in comparison to QPSK.It also presents a comprehensive FPGA implementation... This paper examines theπ/4QPSK modulation communication transmission system,analyzing the performance advantages and disadvantages ofπ/4QPSK in comparison to QPSK.It also presents a comprehensive FPGA implementation scheme for a modulation communication transmission system,integrating RS channel coding,framing,frequency conversion,and other modules.This design is based on practical research and development requirements.The Xilinx Spartan6 chip board was used for board-level verification.Theπ/4QPSK modulated signal was transmitted via D/A conversion and radio frequency,with the transmitted waveform was looped back for reception.After A/D processing,the correctness of the designed modulation transmission scheme was verified. 展开更多
关键词 π/4QPSK modulation fpga
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基于时空特征融合的Encoder-Decoder多步4D短期航迹预测 被引量:2
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作者 石庆研 张泽中 韩萍 《信号处理》 CSCD 北大核心 2023年第11期2037-2048,共12页
航迹预测在确保空中交通安全、高效运行中扮演着至关重要的角色。所预测的航迹信息是航迹优化、冲突告警等决策工具的输入,而预测准确性取决于模型对航迹序列特征的提取能力。航迹序列数据是具有丰富时空特征的多维时间序列,其中每个变... 航迹预测在确保空中交通安全、高效运行中扮演着至关重要的角色。所预测的航迹信息是航迹优化、冲突告警等决策工具的输入,而预测准确性取决于模型对航迹序列特征的提取能力。航迹序列数据是具有丰富时空特征的多维时间序列,其中每个变量都呈现出长短期的时间变化模式,并且这些变量之间还存在着相互依赖的空间信息。为了充分提取这种时空特征,本文提出了基于融合时空特征的编码器-解码器(Spatio-Temporal EncoderDecoder,STED)航迹预测模型。在Encoder中使用门控循环单元(Gated Recurrent Unit,GRU)、卷积神经网络(Convolutional Neural Network,CNN)和注意力机制(Attention,AT)构成的双通道网络来分别提取航迹时空特征,Decoder对时空特征进行拼接融合,并利用GRU对融合特征进行学习和递归输出,实现对未来多步航迹信息的预测。利用真实的航迹数据对算法性能进行验证,实验结果表明,所提STED网络模型能够在未来10 min预测范围内进行高精度的短期航迹预测,相比于LSTM、CNN-LSTM和AT-LSTM等数据驱动航迹预测模型具有更高的精度。此外,STED网络模型预测一个航迹点平均耗时为0.002 s,具有良好的实时性。 展开更多
关键词 4D航迹预测 时空特征 Encoder-decoder 门控循环单元
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