The open nature and heterogeneous architecture of Open Radio Access Network(Open RAN)undermine the consistency of security policies and broaden the attack surface,thereby increasing the risk of security vulnerabilitie...The open nature and heterogeneous architecture of Open Radio Access Network(Open RAN)undermine the consistency of security policies and broaden the attack surface,thereby increasing the risk of security vulnerabilities.The dynamic nature of network performance and traffic patterns in Open RAN necessitates advanced detection models that can overcome the constraints of traditional techniques and adapt to evolving behaviors.This study presents a methodology for effectively detecting malicious traffic in Open RAN by utilizing an Artificial-Intelligence/MachineLearning(AI/ML)Framework.A hybrid Transformer–Convolutional-Neural-Network(Transformer-CNN)ensemble model is employed for anomaly detection.The proposed model generates final predictions through a soft-voting technique based on the predictive outputs of the two models with distinct features.This approach improves accuracy by up to 1.06%and F1 score by 1.48%compared with a hard-voting technique to determine the final prediction.Furthermore,the proposed model achieves an average accuracy of approximately 98.3%depending on the time step,exhibiting a 1.43%increase in accuracy over single-model approaches.Unlike single-model approaches,which are prone to overfitting,the ensemble model resolves the overfitting problem by reducing the deviation in validation loss.展开更多
Ultra-densification of radio access network(RAN)is a key to efficiently support the exponentially growing mobile data traffic in 5 G era.Furthermore,extremely high frequency band like mm Wave band was utilized to solv...Ultra-densification of radio access network(RAN)is a key to efficiently support the exponentially growing mobile data traffic in 5 G era.Furthermore,extremely high frequency band like mm Wave band was utilized to solve the bandwidth shortage problem.However,untra-dense reusing the same radio resource produced severe interference.And the mm Wave link was very harsh due to frequent blockage by obstacles.Therefore a new RAN architecture needed to be introduced to realize ultra-reliable communications in such a severe radio propagation environment.An architecture of distributed MIMO based RAN was presented.Then,enhanced interference coordination(e IC)was described.Finally,the effectiveness of distributed MIMO based RAN with e IC by computer simulation was showed.展开更多
With the increasing frequency of wireless mobile communication,dielectric materials with higher Q×f are required to enhance the signal strength of microwave passive devices and thus compensate for the rapid atten...With the increasing frequency of wireless mobile communication,dielectric materials with higher Q×f are required to enhance the signal strength of microwave passive devices and thus compensate for the rapid attenuation of high-frequency signals during propagation.In order to improve the Q×f of the MgNb2O6 system and study the internal mechanism between the structure and microwave dielectric properties,Ta5+ion is introduced to design and fabricate MgNb_(2-x)Ta_(x)O_(6)(0≤x≤0.8)ceramics by the solid-state reaction method.The single columbite phase and dense structure are observed throughout the entire composition range.All elements(Mg,Nb,Ta,and O)can be detected by X-ray photoelectron spectroscopy.Insights from the Raman spectroscopy and group theoretical analysis reveal that the Ag(2)and Ag(3)modes located at∼905 cm−1 dominate the Raman vibration.In addition,theɛr depends on the polarizability reflected by the C–M equation and Raman shift.Theτf closely relates to the bond energy of the Nb/Ta–O bond and restoring force characterized by average octahedral distortion of[Nb/TaO6].Notably,the crucial factors for the huge improvement of Q×f are clarified deeply,in terms of the lower internal strain,the reduced ordering-induced domain size,and the chemical bond valence closer to the ionic valence state,which promotes the stability of crystal structure.Moreover,the introduction of lower electronegative ions enhances the ability of electrons to compensate for oxygen vacancies,thereby reducing the dielectric loss caused by the conductance.Excellent microwave properties(ɛr=19.2,Q×f=170,000 GHz,andτf=−55.6 ppm℃–1)are achieved in MgNb1.4Ta0.6O6 ceramic,specifically a nearly 40%increase in the Q×f.This work has enriched the theory associated with low dielectric loss and provided the MgNb_(1.4)Ta_(0.6)O_(6) ceramic with a pretty high-Q×f for the application in the design of the 5G/6G wireless communication devices.展开更多
基金supported by the Institute of Information&Communications Technology Planning&Evaluation(IITP)grant funded by the Korea government(MSIT)(RS-2024-00396797,Development of core technology for intelligent O-RAN security platform)。
文摘The open nature and heterogeneous architecture of Open Radio Access Network(Open RAN)undermine the consistency of security policies and broaden the attack surface,thereby increasing the risk of security vulnerabilities.The dynamic nature of network performance and traffic patterns in Open RAN necessitates advanced detection models that can overcome the constraints of traditional techniques and adapt to evolving behaviors.This study presents a methodology for effectively detecting malicious traffic in Open RAN by utilizing an Artificial-Intelligence/MachineLearning(AI/ML)Framework.A hybrid Transformer–Convolutional-Neural-Network(Transformer-CNN)ensemble model is employed for anomaly detection.The proposed model generates final predictions through a soft-voting technique based on the predictive outputs of the two models with distinct features.This approach improves accuracy by up to 1.06%and F1 score by 1.48%compared with a hard-voting technique to determine the final prediction.Furthermore,the proposed model achieves an average accuracy of approximately 98.3%depending on the time step,exhibiting a 1.43%increase in accuracy over single-model approaches.Unlike single-model approaches,which are prone to overfitting,the ensemble model resolves the overfitting problem by reducing the deviation in validation loss.
基金The Research and Development for Further Advancement of the 5th Generation Mobile Communication System(No.JP1000254)。
文摘Ultra-densification of radio access network(RAN)is a key to efficiently support the exponentially growing mobile data traffic in 5 G era.Furthermore,extremely high frequency band like mm Wave band was utilized to solve the bandwidth shortage problem.However,untra-dense reusing the same radio resource produced severe interference.And the mm Wave link was very harsh due to frequent blockage by obstacles.Therefore a new RAN architecture needed to be introduced to realize ultra-reliable communications in such a severe radio propagation environment.An architecture of distributed MIMO based RAN was presented.Then,enhanced interference coordination(e IC)was described.Finally,the effectiveness of distributed MIMO based RAN with e IC by computer simulation was showed.
基金supported by the National Natural Science Foundation of China(No.52172122).
文摘With the increasing frequency of wireless mobile communication,dielectric materials with higher Q×f are required to enhance the signal strength of microwave passive devices and thus compensate for the rapid attenuation of high-frequency signals during propagation.In order to improve the Q×f of the MgNb2O6 system and study the internal mechanism between the structure and microwave dielectric properties,Ta5+ion is introduced to design and fabricate MgNb_(2-x)Ta_(x)O_(6)(0≤x≤0.8)ceramics by the solid-state reaction method.The single columbite phase and dense structure are observed throughout the entire composition range.All elements(Mg,Nb,Ta,and O)can be detected by X-ray photoelectron spectroscopy.Insights from the Raman spectroscopy and group theoretical analysis reveal that the Ag(2)and Ag(3)modes located at∼905 cm−1 dominate the Raman vibration.In addition,theɛr depends on the polarizability reflected by the C–M equation and Raman shift.Theτf closely relates to the bond energy of the Nb/Ta–O bond and restoring force characterized by average octahedral distortion of[Nb/TaO6].Notably,the crucial factors for the huge improvement of Q×f are clarified deeply,in terms of the lower internal strain,the reduced ordering-induced domain size,and the chemical bond valence closer to the ionic valence state,which promotes the stability of crystal structure.Moreover,the introduction of lower electronegative ions enhances the ability of electrons to compensate for oxygen vacancies,thereby reducing the dielectric loss caused by the conductance.Excellent microwave properties(ɛr=19.2,Q×f=170,000 GHz,andτf=−55.6 ppm℃–1)are achieved in MgNb1.4Ta0.6O6 ceramic,specifically a nearly 40%increase in the Q×f.This work has enriched the theory associated with low dielectric loss and provided the MgNb_(1.4)Ta_(0.6)O_(6) ceramic with a pretty high-Q×f for the application in the design of the 5G/6G wireless communication devices.
