Readout errors caused by measurement noise are a significant source of errors in quantum circuits,which severely affect the output results and are an urgent problem to be solved in noisy-intermediate scale quantum(NIS...Readout errors caused by measurement noise are a significant source of errors in quantum circuits,which severely affect the output results and are an urgent problem to be solved in noisy-intermediate scale quantum(NISQ)computing.In this paper,we use the bit-flip averaging(BFA)method to mitigate frequent readout errors in quantum generative adversarial networks(QGAN)for image generation,which simplifies the response matrix structure by averaging the qubits for each random bit-flip in advance,successfully solving problems with high cost of measurement for traditional error mitigation methods.Our experiments were simulated in Qiskit using the handwritten digit image recognition dataset under the BFA-based method,the Kullback-Leibler(KL)divergence of the generated images converges to 0.04,0.05,and 0.1 for readout error probabilities of p=0.01,p=0.05,and p=0.1,respectively.Additionally,by evaluating the fidelity of the quantum states representing the images,we observe average fidelity values of 0.97,0.96,and 0.95 for the three readout error probabilities,respectively.These results demonstrate the robustness of the model in mitigating readout errors and provide a highly fault tolerant mechanism for image generation models.展开更多
球形译码(Sphere Decoding,SD)能够有效地实现极化码最大似然译码的误码性能,文章提出基于比特翻转的多重球形译码树搜索(Multiple Sphere Decoding Tree Searches Based on Bit-Flipping,BF-MSDTS)算法进一步提升短极化码的性能,该算...球形译码(Sphere Decoding,SD)能够有效地实现极化码最大似然译码的误码性能,文章提出基于比特翻转的多重球形译码树搜索(Multiple Sphere Decoding Tree Searches Based on Bit-Flipping,BF-MSDTS)算法进一步提升短极化码的性能,该算法通过扩大半径搜索和翻转不可靠比特提升误码性能,同时利用搜索终止准则和固定可靠比特降低复杂度,有效地解决了多重球形译码树搜索(Multiple Sphere Decoding Tree Searches,MSDTS)算法低信噪比下误码性能不如循环冗余校验(Cyclic Redundancy Check,CRC)辅助的串行消除列表(CRC Aided Successive Cancellation List,CA-SCL)算法的问题.仿真结果表明,在低信噪比时,当误码率为10-4时,与CA-SCL算法比较,提高了0.41dB,与MSDTS算法比较,提高了1.17dB.提出的BF-MSDTS算法的误码性能在较差的信道环境下优于现有的MSDTS算法以及CA-SCL算法.展开更多
针对弱信号条件下传统卫星信号捕获算法无法满足用户需求的问题,在对接收信号进行傅里叶变换的基础上,提出了一种利用四分法估计导航数据比特跳变位和差分相干累加方法相结合的北斗弱信号捕获新算法。与基于FFT的半比特交替和相干累加...针对弱信号条件下传统卫星信号捕获算法无法满足用户需求的问题,在对接收信号进行傅里叶变换的基础上,提出了一种利用四分法估计导航数据比特跳变位和差分相干累加方法相结合的北斗弱信号捕获新算法。与基于FFT的半比特交替和相干累加结合的捕获方法比较可知,该算法数据利用率高,对噪声有良好的抑制效果。仿真结果表明,该算法可实现-38 d B信噪比条件下的北斗弱信号捕获,并可进一步提高软件接收机灵敏度。展开更多
基金Project supported by the Natural Science Foundation of Shandong Province,China (Grant No.ZR2021MF049)Joint Fund of Natural Science Foundation of Shandong Province (Grant Nos.ZR2022LLZ012 and ZR2021LLZ001)。
文摘Readout errors caused by measurement noise are a significant source of errors in quantum circuits,which severely affect the output results and are an urgent problem to be solved in noisy-intermediate scale quantum(NISQ)computing.In this paper,we use the bit-flip averaging(BFA)method to mitigate frequent readout errors in quantum generative adversarial networks(QGAN)for image generation,which simplifies the response matrix structure by averaging the qubits for each random bit-flip in advance,successfully solving problems with high cost of measurement for traditional error mitigation methods.Our experiments were simulated in Qiskit using the handwritten digit image recognition dataset under the BFA-based method,the Kullback-Leibler(KL)divergence of the generated images converges to 0.04,0.05,and 0.1 for readout error probabilities of p=0.01,p=0.05,and p=0.1,respectively.Additionally,by evaluating the fidelity of the quantum states representing the images,we observe average fidelity values of 0.97,0.96,and 0.95 for the three readout error probabilities,respectively.These results demonstrate the robustness of the model in mitigating readout errors and provide a highly fault tolerant mechanism for image generation models.
文摘球形译码(Sphere Decoding,SD)能够有效地实现极化码最大似然译码的误码性能,文章提出基于比特翻转的多重球形译码树搜索(Multiple Sphere Decoding Tree Searches Based on Bit-Flipping,BF-MSDTS)算法进一步提升短极化码的性能,该算法通过扩大半径搜索和翻转不可靠比特提升误码性能,同时利用搜索终止准则和固定可靠比特降低复杂度,有效地解决了多重球形译码树搜索(Multiple Sphere Decoding Tree Searches,MSDTS)算法低信噪比下误码性能不如循环冗余校验(Cyclic Redundancy Check,CRC)辅助的串行消除列表(CRC Aided Successive Cancellation List,CA-SCL)算法的问题.仿真结果表明,在低信噪比时,当误码率为10-4时,与CA-SCL算法比较,提高了0.41dB,与MSDTS算法比较,提高了1.17dB.提出的BF-MSDTS算法的误码性能在较差的信道环境下优于现有的MSDTS算法以及CA-SCL算法.
文摘针对弱信号条件下传统卫星信号捕获算法无法满足用户需求的问题,在对接收信号进行傅里叶变换的基础上,提出了一种利用四分法估计导航数据比特跳变位和差分相干累加方法相结合的北斗弱信号捕获新算法。与基于FFT的半比特交替和相干累加结合的捕获方法比较可知,该算法数据利用率高,对噪声有良好的抑制效果。仿真结果表明,该算法可实现-38 d B信噪比条件下的北斗弱信号捕获,并可进一步提高软件接收机灵敏度。
