Soft decode-and-forward(DF) can combine the advantages of both amplify-and-forward and hard DF in relay channels. In this paper, we propose a low-complexity soft DF scheme based on polar codes, which features two key ...Soft decode-and-forward(DF) can combine the advantages of both amplify-and-forward and hard DF in relay channels. In this paper, we propose a low-complexity soft DF scheme based on polar codes, which features two key techniques: a low-complexity cyclic redundancy check(CRC) aided list successive cancellation(CALSC) decoder and a soft information calculation method. At the relay node, a low-complexity CALSC decoder is designed to reduce the computational complexity by adjusting the list size according to the reliabilities of decoded bits. Based on the path probability metric of the CALSC decoder, we propose a method to compute the soft information of the decoded bits in CALSC. Simulation results show that our proposed scheme outperforms the soft DF based on low-density parity-check codes and the soft DF with belief propagation or soft cancellation decoder, especially in the case when the source-relay channel is at the high signal-to-ratio region.展开更多
Dropping probability of handoff calls and blocking probability of new calls are two important Quality of Service (QoS) measures for LTE-Advanced networks. Applying QoS for Cell edge users in soft frequency reuse schem...Dropping probability of handoff calls and blocking probability of new calls are two important Quality of Service (QoS) measures for LTE-Advanced networks. Applying QoS for Cell edge users in soft frequency reuse scheme in LTE system is a challenge as they already suffer from limited resources. Assigning some resources for handover calls may enhance dropping probability but this is in price of degradation in the blocking probability for new calls in cell-edge. Uniform Fractional Guard Channel (UFGC) is a call admission policy that provides QoS without reserving resources for handover calls. In this paper, the performance of Soft Frequency Reuse (SFR) in presence of Uniform Fractional Guard Channel (UFGC) will be investigated using queuing analysis. The mathematical model and performance metrics will be deduced in this assessment. The impact of UFGC will be evaluated in edge and core part separately. Then the optimal value for the parameter of UFGC will be obtained to minimize the blocking probability of new calls with the constraint on the upper bound on the dropping probability of handoff calls.展开更多
The problem of soft-input so,output （ SISO ） detection for time-varying frequency-selec- tive fading channels is considered. Based on a suitably-designed factor graph and the sum-product al- gorithm, a low-complexit...The problem of soft-input so,output （ SISO ） detection for time-varying frequency-selec- tive fading channels is considered. Based on a suitably-designed factor graph and the sum-product al- gorithm, a low-complexity iterative message passing scheme is proposed for joint channel estima- tion, equalization and decoding. Two kinds of schedules （parallel and serial） are adopted in message updates to produce two algorithms with different latency. The computational complexity per iteration of the proposed algorithms grows only linearly with the channel length, which is a significantly de- crease compared to the optimal maximum a posteriori （MAP） detection with the exponential com- plexity. Computer simulations demonstrate the effectiveness of the proposed schemes in terms of bit error rate performance.展开更多
目的观察软通道穿刺引流术治疗中等量高血压脑出血的临床效果。方法选取2021年6月—2022年6月在福建省立医院进行手术治疗的300例中等量高血压脑出血患者,采用随机数字表法分为对照组与观察组,每组各150例。对照组采用开颅血肿清除术的...目的观察软通道穿刺引流术治疗中等量高血压脑出血的临床效果。方法选取2021年6月—2022年6月在福建省立医院进行手术治疗的300例中等量高血压脑出血患者,采用随机数字表法分为对照组与观察组,每组各150例。对照组采用开颅血肿清除术的方法为患者进行治疗,观察组采用软通道穿刺引流术为患者进行治疗,比较两组治疗效果。结果与对照组比较,观察组中等量高血压脑出血患者的救治成功率更高,治疗有效性更高,术后并发症发生率更低,且经过治疗后的临床神经功能缺损评分(national institute of health stroke scale,NIHSS)更低,生活质量和睡眠质量更高(P<0.05)。结论针对中等量高血压脑出血患者,采取软通道穿刺引流术的效果更优,患者的治疗有效性和神经功能状况得到改善,并发症情况较低,且患者治疗后生活质量和睡眠质量得到提升,治疗优势突出,可在临床大量推广。展开更多
By applying bromide ion as tracer,the channeling flow has been quantitatively described in saline rice soil and alkaline soil of Da,an City,Jilin Province of China.Breakthrough curves of bromide ion in the saline rice...By applying bromide ion as tracer,the channeling flow has been quantitatively described in saline rice soil and alkaline soil of Da,an City,Jilin Province of China.Breakthrough curves of bromide ion in the saline rice soils after 1-year cultivation and 5-year cultivation and alkaline soil have been attained.Results show that the rice cultivation practice can improve the alkaline soil structure,however,it can accelerate the development of channeling flow pathway.Therefore,the channeling flow pathway has been developed widely in saline rice soil,but rarely in the alkaline soil.Three models of convection-dispersion equation(CDE),transfer functional model(TFM) and Back-Progation Network(BP Network) were used to simulate the transportation process of bromide ion.The peaks of probability density function of saline rice soil are higher with left skewed feature compared with that of the alkaline soil.It shows that the TFM and CDE can simulate the transportation process of the bromide ion in saline rice soil after 5-year cultivation,however,some deviation exists when it was used to simulate transportation process of bromide ion in saline rice soil after 1-year cul-tivation and alkaline soil;BP network can effectively simulate transportation process of bromide ion in both saline rice soil and alkaline soil.展开更多
基金supported by the National Natural Science Foundation of China(No.61171099,No.61671080),Nokia Beijing Bell lab
文摘Soft decode-and-forward(DF) can combine the advantages of both amplify-and-forward and hard DF in relay channels. In this paper, we propose a low-complexity soft DF scheme based on polar codes, which features two key techniques: a low-complexity cyclic redundancy check(CRC) aided list successive cancellation(CALSC) decoder and a soft information calculation method. At the relay node, a low-complexity CALSC decoder is designed to reduce the computational complexity by adjusting the list size according to the reliabilities of decoded bits. Based on the path probability metric of the CALSC decoder, we propose a method to compute the soft information of the decoded bits in CALSC. Simulation results show that our proposed scheme outperforms the soft DF based on low-density parity-check codes and the soft DF with belief propagation or soft cancellation decoder, especially in the case when the source-relay channel is at the high signal-to-ratio region.
文摘Dropping probability of handoff calls and blocking probability of new calls are two important Quality of Service (QoS) measures for LTE-Advanced networks. Applying QoS for Cell edge users in soft frequency reuse scheme in LTE system is a challenge as they already suffer from limited resources. Assigning some resources for handover calls may enhance dropping probability but this is in price of degradation in the blocking probability for new calls in cell-edge. Uniform Fractional Guard Channel (UFGC) is a call admission policy that provides QoS without reserving resources for handover calls. In this paper, the performance of Soft Frequency Reuse (SFR) in presence of Uniform Fractional Guard Channel (UFGC) will be investigated using queuing analysis. The mathematical model and performance metrics will be deduced in this assessment. The impact of UFGC will be evaluated in edge and core part separately. Then the optimal value for the parameter of UFGC will be obtained to minimize the blocking probability of new calls with the constraint on the upper bound on the dropping probability of handoff calls.
基金Supported by the National Natural Science Foundation of China(61201181)Specialized Research Fund for the Doctoral Program of Higher Education(20121101120020)the Co-innovation Laboratory of Aerospace Broadband Network Technology
文摘The problem of soft-input so,output （ SISO ） detection for time-varying frequency-selec- tive fading channels is considered. Based on a suitably-designed factor graph and the sum-product al- gorithm, a low-complexity iterative message passing scheme is proposed for joint channel estima- tion, equalization and decoding. Two kinds of schedules （parallel and serial） are adopted in message updates to produce two algorithms with different latency. The computational complexity per iteration of the proposed algorithms grows only linearly with the channel length, which is a significantly de- crease compared to the optimal maximum a posteriori （MAP） detection with the exponential com- plexity. Computer simulations demonstrate the effectiveness of the proposed schemes in terms of bit error rate performance.
文摘目的观察软通道穿刺引流术治疗中等量高血压脑出血的临床效果。方法选取2021年6月—2022年6月在福建省立医院进行手术治疗的300例中等量高血压脑出血患者,采用随机数字表法分为对照组与观察组,每组各150例。对照组采用开颅血肿清除术的方法为患者进行治疗,观察组采用软通道穿刺引流术为患者进行治疗,比较两组治疗效果。结果与对照组比较,观察组中等量高血压脑出血患者的救治成功率更高,治疗有效性更高,术后并发症发生率更低,且经过治疗后的临床神经功能缺损评分(national institute of health stroke scale,NIHSS)更低,生活质量和睡眠质量更高(P<0.05)。结论针对中等量高血压脑出血患者,采取软通道穿刺引流术的效果更优,患者的治疗有效性和神经功能状况得到改善,并发症情况较低,且患者治疗后生活质量和睡眠质量得到提升,治疗优势突出,可在临床大量推广。
基金Under the auspices of the Key Innovation Project of Chinese Academy of Sciences (No. KZCX1-SW-19-02)
文摘By applying bromide ion as tracer,the channeling flow has been quantitatively described in saline rice soil and alkaline soil of Da,an City,Jilin Province of China.Breakthrough curves of bromide ion in the saline rice soils after 1-year cultivation and 5-year cultivation and alkaline soil have been attained.Results show that the rice cultivation practice can improve the alkaline soil structure,however,it can accelerate the development of channeling flow pathway.Therefore,the channeling flow pathway has been developed widely in saline rice soil,but rarely in the alkaline soil.Three models of convection-dispersion equation(CDE),transfer functional model(TFM) and Back-Progation Network(BP Network) were used to simulate the transportation process of bromide ion.The peaks of probability density function of saline rice soil are higher with left skewed feature compared with that of the alkaline soil.It shows that the TFM and CDE can simulate the transportation process of the bromide ion in saline rice soil after 5-year cultivation,however,some deviation exists when it was used to simulate transportation process of bromide ion in saline rice soil after 1-year cul-tivation and alkaline soil;BP network can effectively simulate transportation process of bromide ion in both saline rice soil and alkaline soil.
