paper_authors: Simone Cammarasana, Giuseppe Patanè
for: solves two minimization problems (approximation and denoising) with different constraints using high-performance computing.
methods: compares and analyzes different minimization methods in terms of functional computation, convergence, execution time, and scalability properties.
results: PRAXIS is the best optimizer in terms of minima computation, with an efficiency of 38% for approximation and 46% for denoising.Here is the full text in Simplified Chinese:
for: 本研究 solves two minimization problems (approximation和denoising) with different constraints using high-performance computing.
methods: Compares and analyzes different minimization methods in terms of functional computation, convergence, execution time, and scalability properties.
results: PRAXIS is the best optimizer in terms of minima computation, with an efficiency of 38% for approximation and 46% for denoising.Abstract
Several physics and engineering applications involve the solution of a minimisation problem to compute an approximation of the input signal. Modern computing hardware and software apply high-performance computing to solve and considerably reduce the execution time. We compare and analyse different minimisation methods in terms of functional computation, convergence, execution time, and scalability properties, for the solution of two minimisation problems (i.e., approximation and denoising) with different constraints that involve computationally expensive operations. These problems are attractive due to their numerical and analytical properties, and our general analysis can be extended to most signal-processing problems. We perform our tests on the Cineca Marconi100 cluster, at the 26th position in the top500 list. Our experimental results show that PRAXIS is the best optimiser in terms of minima computation: the efficiency of the approximation is 38% with 256 processes, while the denoising has 46% with 32 processes.
摘要
许多物理和工程应用中需要解决最小化问题以计算输入信号的近似值。现代计算硬件和软件通过高性能计算解决这些问题，大大减少了执行时间。我们对不同的最小化方法进行比较和分析，考虑其函数计算、收敛、执行时间和可扩展性特性，以解决两个最小化问题（即近似和净化），它们具有不同的计算约束。这些问题具有数字和分析性质，我们的总分析可以扩展到大多数信号处理问题。我们在Cineca Marconi100集群上进行测试，该集群在top500列表中排名第26位。我们的实验结果显示，PRAXIS是最佳优化器，在256个进程中，近似计算效率为38%，而净化计算效率为46%。
Terahertz Communication Testbeds: Challenges and Opportunities
results: 该SDR-THz测试平台可以达到3.2 Mbps的传输速率，并且可以通过使用反射板来精细调整频率错误和偏斜错误，但需要至少14.91 dB的信号噪声比。结果表明SDR基带信号生成在THz通信中完全可行，并且开 up了许多机会来超越实验研究中的硬件限制。Abstract
This study investigates an experimental software defined radio (SDR) implementation on 180 GHz. Rate scarcity and frequency sparsity are discussed as hardware bottlenecks. Experimental challenges are explained along with the derived system model of such a cascaded structure. Multiple error metrics for the terahertz (THz) signal are acquired, and various case scenarios are subsequently compared. The SDR-THz testbed reaches 3.2 Mbps with < 1 degree skew error. The use of a reflector plate can fine-tune the frequency error and gain imbalance in the expense of at least 14.91 dB signal-to-noise ratio. The results demonstrate the complete feasibility of SDR-based baseband signal generation in THz communication, revealing abundant opportunities to overcome hardware limitations in experimental research.
摘要
Reconfigurable Intelligent Surface & Edge – An Introduction of an EM manipulation structure on obstacles’ edge
results: 在不同场景下，提出了一种新的电磁振荡结构，可以在障碍物边缘进行静态电磁环境修改，并且在不同场景下实现更好的覆盖性能。Abstract
Reconfigurable Intelligent Surface (RIS) or metasurface is one of the important enabling technologies in mobile cellular networks that can effectively enhance the signal coverage performance in obstructed regions, and it is generally deployed on surfaces different from obstacles to redirect electromagnetic (EM) waves by reflection, or covered on objects' surfaces to manipulate EM waves by refraction. In this paper, Reconfigurable Intelligent Surface & Edge (RISE) is proposed to extend RIS' abilities of reflection and refraction over surfaces to diffraction around obstacles' edge for better adaptation to specific coverage scenarios. Based on that, this paper analyzes the performance of several different deployment locations and EM manipulation structure designs for different coverage scenarios. Then a novel EM manipulation structure deployed at the obstacles' edge is proposed to achieve static EM environment modification. Simulations validate the preference of the schemes for different scenarios and the new structure achieves better coverage performance than other typical structures in the static scheme.
摘要
reh-kon-fig-yur-uh-ble in-tel-li-jent sur-fis (RIS) or meh-tah-sur-fis is one of the important en-abling tech-nolo-gies in mo-bile cel-lu-lar net-works that can ef-fect-ively en-hance the sig-nal cov-er-age per-for-mance in ob-structed re-gions, and it is gen-er-ally de-ployed on sur-faces dif-fer-ent from ob-stacles to re-dir-ect EM waves by re-flec-tion, or cov-ered on ob-jects' sur-faces to man-i-pulate EM waves by re-frac-tion. In this pa-per, Re-config-urable In-tel-li-gent Sur-face & Edge (RISE) is pro-posed to ex-tend RIS' abil-i-ties of re-flec-tion and re-frac-tion over sur-faces to dif-fraction around ob-stacles' edge for bet-ter ad-ap-tion to spec-i-fic cov-er-age scena-rios. Based on that, this pa-per an-a-lyzes the per-for-mance of se-ver-al dif-fer-ent de-ploy-ment lo-ca-tions and EM man-i-pu-la-tion struc-ture de-signs for dif-fer-ent cov-er-age scena-rios. Then a no-vel EM man-i-pu-la-tion struc-ture de-ployed at the ob-stacles' edge is pro-posed to achieve stat-ic EM en-vi-ron-ment mod-i-fi-ca-tion. Sim-u-la-tions val-id-ate the pref-er-ence of the schemes for dif-fer-ent scena-rios and the new struc-ture achieves bet-ter cov-er-age per-for-mance than other typ-i-cal struc-tures in the stat-ic scheme.
results: 本文的数据分析表明，DDP和DIP方法可以大幅提高ISAC信号中的探测性能，而且这些方法可以适应不同的随机信号模式。此外，本文还提出了一种可靠的算法来解决ISAC信号中的随机信号设计问题。Abstract
Radar systems typically employ well-designed deterministic signals for target sensing, while integrated sensing and communications (ISAC) systems have to adopt random signals to convey useful information. This paper analyzes the sensing and ISAC performance relying on random signaling in a multiantenna system. Towards this end, we define a new sensing performance metric, namely, ergodic linear minimum mean square error (ELMMSE), which characterizes the estimation error averaged over random ISAC signals. Then, we investigate a data-dependent precoding (DDP) scheme to minimize the ELMMSE in sensing-only scenarios, which attains the optimized performance at the cost of high implementation overhead. To reduce the cost, we present an alternative data-independent precoding (DIP) scheme by stochastic gradient projection (SGP). Moreover, we shed light on the optimal structures of both sensing-only DDP and DIP precoders. As a further step, we extend the proposed DDP and DIP approaches to ISAC scenarios, which are solved via a tailored penalty-based alternating optimization algorithm. Our numerical results demonstrate that the proposed DDP and DIP methods achieve substantial performance gains over conventional ISAC signaling schemes that treat the signal sample covariance matrix as deterministic, which proves that random ISAC signals deserve dedicated precoding designs.
摘要
射频系统通常使用良好设计的决定性信号进行目标探测，而统合探测通信（ISAC）系统则必须运用随机信号传递有用信息。本文分析了使用随机信号的探测和ISAC性能，并定义了一个新的探测性能指标，即随机线性最小平均方差（ELMMSE），用于描述随机ISAC信号中的估计误差。然后，我们调查了一个基于数据依赖的实现（DDP）策略，以减少ELMMSE的值，并提出了一个基于随机投影（SGP）的替代策略。此外，我们还考虑了两种探测只的DDP和DIP预设的结构。最后，我们将这些方法扩展到ISAC场景，这些问题透过一个特别设计的罚则基于交互运算法解决。我们的数据分析结果显示，提案的DDP和DIP方法可以与传统ISAC信号传递方案相比，实现substantial的性能提升，这证明了随机ISAC信号值得特别的预设设计。
Carrier Frequency Offset Estimation for OCDM with Null Subchirps
for: investigate the carrier frequency offset (CFO) identifiability problem in orthogonal chirp division multiplexing (OCDM) systems.
methods: propose a transmission scheme by inserting consecutive null subchirps, and develop a CFO estimator to achieve a full acquisition range.
results: demonstrate that the proposed transmission scheme not only helps to resolve CFO identifiability issues but also enables multipath diversity for OCDM systems, and simulation results corroborate the theoretical findings.Here’s the full translation in Simplified Chinese:
results: 表明提议的传输方案不仅能够解决 CFO 可识别性问题，还能够为 OCDM 系统带来多Path 多普适性。 simulation results 证明了理论发现。Abstract
In this paper, we investigate the carrier frequency offset (CFO) identifiability problem in orthogonal chirp division multiplexing (OCDM) systems. We propose a transmission scheme by inserting consecutive null subchirps. A CFO estimator is accordingly developed to achieve a full acquisition range. We further demonstrate that the proposed transmission scheme not only help to resolve CFO identifiability issues but also enable multipath diversity for OCDM systems. Simulation results corroborate our theoretical findings.
摘要
在这篇论文中，我们研究了扩展幂分多路复用（OCDM）系统中的载波频率偏移（CFO）可识别问题。我们提议了插入连续null子频谱的传输方案，并开发了一种CFO估计器以实现全范围的获得。我们还证明了我们的传输方案不仅能够解决CFO可识别问题，还能够启用OCDM系统中的多路幂资源。实验结果与我们的理论发现相符。Here's the word-for-word translation:在这篇论文中，我们研究了扩展幂分多路复用（OCDM）系统中的载波频率偏移（CFO）可识别问题。我们提议了插入连续null子频谱的传输方案，并开发了一种CFO估计器以实现全范围的获得。我们还证明了我们的传输方案不仅能够解决CFO可识别问题，还能够启用OCDM系统中的多路幂资源。实验结果与我们的理论发现相符。
Moving Target Sensing for ISAC Systems in Clutter Environment
results: 作者透过实验结果显示了这些提议的方法的有效性。Abstract
In this paper, we consider the moving target sensing problem for integrated sensing and communication (ISAC) systems in clutter environment. Scatterers produce strong clutter, deteriorating the performance of ISAC systems in practice. Given that scatterers are typically stationary and the targets of interest are usually moving, we here focus on sensing the moving targets. Specifically, we adopt a scanning beam to search for moving target candidates. For the received signal in each scan, we employ high-pass filtering in the Doppler domain to suppress the clutter within the echo, thereby identifying candidate moving targets according to the power of filtered signal. Then, we adopt root-MUSIC-based algorithms to estimate the angle, range, and radial velocity of these candidate moving targets. Subsequently, we propose a target detection algorithm to reject false targets. Simulation results validate the effectiveness of these proposed methods.
摘要
在这篇论文中，我们考虑了 интеграцион感知通信（ISAC）系统在噪声环境中的移动目标感知问题。噪声会对ISAC系统的性能产生负面影响，因此我们专注于感知移动目标。具体来说，我们采用扫描射频搜索移动目标候选人。对每次扫描得到的信号，我们使用高频滤波器在Doppler域进行高频滤波，以便从响应中排除噪声，并根据过滤后的信号强度确定候选移动目标。然后，我们采用基于MUSIC算法的根幂算法来估算候选移动目标的角度、距离和垂线速度。最后，我们提出了一种目标检测算法，以排除假目标。实验结果证明了我们提出的方法的有效性。
Integrated Sensing and Communications in Clutter Environment
results: 我们的方案在实际实验中得到了证明，比较于忽略环境噪声的现有ISAC方法，我们的方案可以更好地探测动态目标并估计其角度、距离和速度。特别是，动态目标探测和角度估计通过角度-Doppler光谱估计（ADSE）和多个子载波（MSJD）的共同检测，而距离和速度估计通过扩展子空间算法。Abstract
In this paper, we propose a practical integrated sensing and communications (ISAC) framework to sense dynamic targets from clutter environment while ensuring users communications quality. To implement communications function and sensing function simultaneously, we design multiple communications beams that can communicate with the users as well as one sensing beam that can rotate and scan the entire space. To minimize the interference of sensing beam on existing communications systems, we divide the service area into sensing beam for sensing (S4S) sector and communications beam for sensing (C4S) sector, and provide beamforming design and power allocation optimization strategies for each type sector. Unlike most existing ISAC studies that ignore the interference of static environmental clutter on target sensing, we construct a mixed sensing channel model that includes both static environment and dynamic targets. When base station receives the echo signals, the mean phasor cancellation (MPC) method is employed to filter out the interference from static environmental clutter and to extract the effective dynamic target echoes. Then a complete and practical dynamic target sensing scheme is designed to detect the presence of dynamic targets and to estimate their angles, distances, and velocities. In particular, dynamic target detection and angle estimation are realized through angle-Doppler spectrum estimation (ADSE) and joint detection over multiple subcarriers (MSJD), while distance and velocity estimation are realized through the extended subspace algorithm. Simulation results demonstrate the effectiveness of the proposed scheme and its superiority over the existing methods that ignore environmental clutter.
摘要
在这篇论文中，我们提出了一种实用的集成感知通信（ISAC）框架，以感知动态目标在噪声环境中的探测，并保证用户的通信质量。为实现通信功能和感知功能的同时实现，我们设计了多个通信ibeam，可以与用户进行通信，同时还有一个感知ibeam，可以在整个空间中旋转和扫描。为了减少感知ibeam对现有通信系统的干扰，我们将服务区分为感知ibeam（S4S） сектор和通信ibeam（C4S） сектор，并提供了ibeamforming设计和功率分配优化策略 для每种类型的 сектор。与大多数现有ISAC研究不同，我们构建了一种混合感知通道模型，包括了静止环境和动态目标。当基站接收回射信号时，我们使用meanphasor抑制（MPC）方法来筛选静止环境干扰，并提取有效的动态目标回射信号。然后，我们设计了一种实用的动态目标探测方案，以检测动态目标的存在和角度、距离和速度的估算。具体来说，动态目标检测和角度估算通过角度-Doppler спектrum估算（ADSE）和多个子载波（MSJD）的联合检测来实现，而距离和速度估算则通过扩展子空间算法来实现。 simulation结果表明我们的方案的效果和现有方法的差异，并且我们的方案在感知环境中的干扰下表现更佳。