arXiv subjects

Junfeng Deng

Publications and source records attributed to Junfeng Deng.

5 recordsLinked to original sources

arXiv2025

Flexible Cylindrical Arrays with Movable Antennas for MISO System: Beamforming and Position Optimization

As wireless communication advances toward the 6G era, the demand for ultra-reliable, high-speed, and ubiquitous connectivity is driving the exploration of new degrees-of-freedom (DoFs) in communication systems. Among the key enabling technologies, Movable Antennas (MAs) integrated into Flexible Cylindrical Arrays (FCLA) have shown great potential in optimizing wireless communication by providing spatial flexibility. This paper proposes an innovative optimization framework that leverages the dynamic mobility of FCLAs to improve communication rates and overall system performance. By employing Fractional Programming (FP) for alternating optimization of beamforming and antenna positions, the system enhances throughput and resource utilization. Additionally, a novel Constrained Grid Search-Based Adaptive Moment Estimation Algorithm (CGS-Adam) is introduced to optimize antenna positions while adhering to antenna spacing constraints. Extensive simulations validate that the proposed system, utilizing movable antennas, significantly outperforms traditional fixed antenna optimization, achieving up to a 31\% performance gain in general scenarios. The integration of FCLAs in wireless networks represents a promising solution for future 6G systems, offering improved coverage, energy efficiency, and flexibility.

eess.SP↗

arXiv2022

VFed-SSD: Towards Practical Vertical Federated Advertising

As an emerging secure learning paradigm in lever-aging cross-agency private data, vertical federatedlearning (VFL) is expected to improve advertising models by enabling the joint learning of complementary user attributes privately owned by the advertiser and the publisher. However, there are two key challenges in applying it to advertising systems: a) the limited scale of labeled overlapping samples, and b) the high cost of real-time cross-agency serving. In this paper, we propose a semi-supervised split distillation framework VFed-SSD to alleviate the two limitations. We identify that: i)there are massive unlabeled overlapped data available in advertising systems, and ii) we can keep a balance between model performance and inference cost by decomposing the federated model. Specifically, we develop a self-supervised task MatchedPair Detection (MPD) to exploit the vertically partitioned unlabeled data and propose the Split Knowledge Distillation (SplitKD) schema to avoid cross-agency serving. Empirical studies on three industrial datasets exhibit the effectiveness of ourmethods, with the median AUC over all datasets improved by 0.86% and 2.6% in the local andthe federated deployment mode respectively. Overall, our framework provides an efficient federation-enhanced solution for real-time display advertising with minimal deploying cost and significant performance lift.

cs.LG↗

arXiv2012

Dependence of entanglement on initial states under amplitude damping channel in non-inertial frames

Under amplitude damping channel, the dependence of the entanglement on the initial states $|Θ>_{1}$ and $|Θ>_{2}$, which reduce to four orthogonal Bell states if we take the parameter of states $α=\pm 1/\sqrt{2}$ are investigated. We find that the entanglements for different initial states will decay along different curves even with the same acceleration and parameter of the states. We note that, in an inertial frame, the sudden death of the entanglement for $|Θ>_{1}$ will occur if $α>1/\sqrt{2}$, while it will not take place for $|Θ>_{2}$ for any $α$. We also show that the possible range of the sudden death of the entanglement for $|Θ>_{1}$ is larger than that for $|Θ>_{2}$. There exist two groups of Bell state here we can't distinguish only by concurrence.

quant-ph↗

arXiv2010

How the Hawking effect and prepared states affect Entanglement distillability of Dirac fields

How the Hawking effect and the prepared states influence the entanglement distillability of Dirac fields in the Schwarzschild spacetime is studied by using the Werner states which are composed of the maximum or generic entangled states. It is found that the states are entangled when the parameter of the Werner states, $F$, satisfies $τ<F\leq 1$ in which $τ$ is influenced both by the Hawking temperature of the black hole and energy of the fields. It is also shown that although the parameter of the generic entangled states, $α$, affects the entanglement, it does not change the range of the parameter, $F$, where the states are entangled for the case of generic entangled states.

quant-ph↗

arXiv2010

Classical correlation and quantum discord sharing of Dirac fields in noninertial frames

The classical and quantum correlations sharing between modes of the Dirac fields in the noninertial frame are investigated. It is shown that: (i) The classical correlation for the Dirac fields decreases as the acceleration increases, which is different from the result of the scalar field that the classical correlation is independent of the acceleration; (ii) There is no simple dominating relation between the quantum correlation and entanglement for the Dirac fields, which is unlike the scalar case where the quantum correlation is always over and above the entanglement; (iii) As the acceleration increases, the correlations between modes $I$ and $II$ and between modes $A$ and $II$ increase, but the correlations between modes $A$ and $I$ decrease.

quant-ph↗