References of "Wu, Linlong 50043014"
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See detailRecursive UE Localization for a Multi-RIS-Assisted Wireless System in an Obstacle-Dense Environment
Zhao, Sibo; Liu, Yuan UL; Wu, Linlong UL et al

Scientific Conference (in press)

Accurate user equipment (UE) localization in an obstacle-dense environment is quite challenging due to the insufficiency of line-of-sight (LoS) links. However, the reconfigurable intelligent surface (RIS ... [more ▼]

Accurate user equipment (UE) localization in an obstacle-dense environment is quite challenging due to the insufficiency of line-of-sight (LoS) links. However, the reconfigurable intelligent surface (RIS) has the potential for offering alternative RIS-assisted LoS links to refine the localization results. In this paper, a recursive localization scheme is proposed based on an iterative RIS selection strategy, with the help of prior knowledge of the propagation environment. And numerical results based on a geometry-based channel simulator in a typical composite urban environment exhibit the improvement of localization accuracy. [less ▲]

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See detailDistributed 5G NR-based integrated sensing and communication systems: Frame structure and performance analysis
Shi, Shengnan; Cheng, Ziyang; Wu, Linlong UL et al

in 2022 30th European Signal Processing Conference (EUSIPCO) (2022, October 18)

This paper discusses a distributed Integrated Sensing and Communication (ISAC) network based on 5G NR. Each BS in the cellular network adopts half-duplex operation, and every three adjacent BSs construct ... [more ▼]

This paper discusses a distributed Integrated Sensing and Communication (ISAC) network based on 5G NR. Each BS in the cellular network adopts half-duplex operation, and every three adjacent BSs construct a cooperative sensing system. Based on the 5G NR standard frame configuration, we develop a new procedure and protocol to support the proposed ISAC network. Under this network, we analyze the performance of both sensing and communication in practical scenarios. Simulations show the effectiveness of the proposed ISAC network. [less ▲]

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See detailHybrid Beamforming Design for OFDM Dual-Function Radar-Communication System with Double-Phase-Shifter Structure
Wang, Bowen; Cheng, Ziyang; Wu, Linlong UL et al

in 2022 30th European Signal Processing Conference (EUSIPCO) (2022, October 18)

In this paper, the problem of the hybrid beamforming (HBF) for a millimeter wave (mmWave) orthogonal frequency division multiplexing (OFDM) dual-function radar-communication (DFRC) system in the presence ... [more ▼]

In this paper, the problem of the hybrid beamforming (HBF) for a millimeter wave (mmWave) orthogonal frequency division multiplexing (OFDM) dual-function radar-communication (DFRC) system in the presence of signal-dependent interference is studied. The HBF network is based on the subarray connection architecture combining with the double-phase-shifter (DPS) structure. To achieve the dual functionality, we formulate the problem by maximizing the communication spectral efficiency subject to the constraints of radar integrated side-lobe to main-lobe ratio (ISMR), space-frequency nulling (SFN) and energy. An efficient algorithm based on the consensus alternating direction method of multipliers (CADMM) frame-work is developed to tackle the resultant nonconvex problem. Simulation results demonstrate the superiority of the proposed DPS structure and HBF algorithm. [less ▲]

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See detailExploiting constructive interference in symbol level hybrid beamforming for dual-function radar-communication system
Wang, Bowen; Wu, Linlong UL; Cheng, Ziyang et al

in IEEE Wireless Communications Letters (2022), 11(10), 2071--2075

In this letter, we study the Hybrid Beamforming (HBF) design for a Dual-Function Radar-Communication (DFRC) system, which serves Multiple Users (MUs) and detects a target in the presence of signal ... [more ▼]

In this letter, we study the Hybrid Beamforming (HBF) design for a Dual-Function Radar-Communication (DFRC) system, which serves Multiple Users (MUs) and detects a target in the presence of signal-dependent clutters, simultaneously. Unlike conventional beamforming strategies, we propose a novel one on the symbol level, which exploits Constructive Interference (CI) to achieve a trade-off between radar and communication using one platform. To implement this novel strategy, we jointly design the DFRC transmit HBF and radar receive beamforming by maximizing the radar Signal to Interference plus Noise Ratio (SINR) while ensuring the Quality of Service (QoS) of downlink communication. To tackle the formulated non-convex problem, we propose an iterative algorithm, which combines the Majorization-Minimization (MM) and Alternating Direction Method of Multipliers (ADMM) judiciously. The numerical experiments indicate that our algorithm yields the CI properly for robust communications and achieves better performance than the conventional HBF benchmarks in both communication bit error rate and radar SINR. [less ▲]

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See detailA 3D Indoor Localization Approach Based on Spherical Wave-front and Channel Spatial Geometry
Liu, Yuan UL; Wu, Linlong UL; Alaeekerahroodi, Mohammad UL et al

in Liu, Yuan; Wu, Linlong; Alaeekerahroodi, Mohammad (Eds.) et al 2022 IEEE 12th Sensor Array and Multichannel Signal Processing Workshop (SAM) (2022, June)

Because of the near-field nature of radio propagation, spherical wave-front and multipath effect are prominent in indoor scenarios, making localization even more difficult. In this paper, we propose a ... [more ▼]

Because of the near-field nature of radio propagation, spherical wave-front and multipath effect are prominent in indoor scenarios, making localization even more difficult. In this paper, we propose a three-dimensional (3D) indoor localization algorithm that takes these issues into account. Specifically, we first adopted a high-resolution channel parameter estimation method for path delays based on the Space-Alternating Generalized Expectation-maximization (SAGE), and then these path delays are adopted in the 3D localization principles based on the target-antenna geometry. The proposed algorithm is validated by numerical simulations, where the channel data is generated by the propagation graph (PG) to model the true wireless propagation closely in the testing scenarios. The results demonstrate that the proposed approach can deal with both point and non-point targets with 3D localization errors of less than 30 cm for 97% of the testing trails in a 10×20×3 m3 indoor space. [less ▲]

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See detailA Hybrid Approach to Optimal TOA-Sensor Placement With Fixed Shared Sensors for Simultaneous Multi-Target Localization
Xu, Sheng; Wu, Linlong UL; Doğançay, Kutluyıl et al

in IEEE Transactions on Signal Processing (2022)

This paper focuses on optimal time-of-arrival (TOA) sensor placement for multiple target localization simultaneously. In previous work, different solutions only using non-shared sensors to localize ... [more ▼]

This paper focuses on optimal time-of-arrival (TOA) sensor placement for multiple target localization simultaneously. In previous work, different solutions only using non-shared sensors to localize multiple targets have been developed. Those methods localize different targets one-by-one or use a large number of mobile sensors with many limitations, such as low effectiveness and high network complexity. In this paper, firstly, a novel optimization model for multi-target localization incorporating shared sensors is formulated. Secondly, the systematic theoretical results of the optimal sensor placement are derived and concluded using the A-optimality criterion, i.e., minimizing the trace of the inverse Fisher information matrix (FIM), based on rigorous geometrical derivations. The reachable optimal trace of Cramér-Rao lower bound (CRLB) is also derived. It can provide optimal conditions for many cases and even closed form solutions for some special cases. Thirdly, a novel numerical optimization algorithm to quickly find and calculate the (sub-)optimal placement and achievable lower bound is explored, when the model becomes complicated with more practical constraints. Then, a hybrid method for solving the most general situation, integrating both the analytical and numerical solutions, is proposed. Finally, the correctness and effectiveness of the proposed theoretical and mathematical methods are demonstrated by several simulation examples. [less ▲]

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See detailIntegrated Trajectory Optimization and Cubature Kalman Filter for UAV-Based Target Tracking with Unknown Initial Position
Xu, Sheng; Wu, Linlong UL; MR, Bhavani Shankar et al

in 2022 IEEE 12th Sensor Array and Multichannel Signal Processing Workshop (SAM) (2022)

This paper investigates the target localization/tracking by angle-of-arrival (AOA) sensors carried on an unmanned aerial vehicle (UAV). In many practical applications, the UAV's own position is not ... [more ▼]

This paper investigates the target localization/tracking by angle-of-arrival (AOA) sensors carried on an unmanned aerial vehicle (UAV). In many practical applications, the UAV's own position is not available, since the global position system (GPS) can hardly work in the indoor environment or interference region. Therefore, considering the unknown initial position of the UAV, a modified cubature Kalman filter (CKF) is developed to estimate both the target states and UAV's initial position jointly by leveraging a benchmark anchor. To further improve the estimation efficiency, we propose an algorithm to optimize the UAV flying trajectory by minimizing the the trace of the estimation covariance matrix in the CKF. According to the simulation results, an observation is found that the UAV will keeping flying alternatively between the anchor and target to guarantee the estimation performance. [less ▲]

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See detailImproving Pulse-Compression Weather Radar via the Joint Design of Subpulses and Extended Mismatch Filter
Wu, Linlong UL; Alaeekerahroodi, Mohammad UL; Mysore Rama Rao, Bhavani Shankar UL

in IGARSS 2022-2022 IEEE International Geoscience and Remote Sensing Symposium (2022)

Pulse compression can enhance both the performance in range resolution and sensitivity for weather radar. However, it will introduce the issue of high sidelobes if not delicately implemented. Motivated by ... [more ▼]

Pulse compression can enhance both the performance in range resolution and sensitivity for weather radar. However, it will introduce the issue of high sidelobes if not delicately implemented. Motivated by this fact, we focus on the pulse compression design for weather radar in this paper. Specifically, we jointly design both the subpulse codes and extended mismatch filter based on the alternating direction method of multipliers (ADMM). This joint design will yield a pulse compression with low sidelobes, which equivalently implies a high signal-to-interference-plus-noise ratio (SINR) and a low estimation error on meteorological reflectivity. The experiment results demonstrate the efficacy of the proposed pulse compression strategy since its achieved meteorological reflectivity estimations are highly similar to the ground truth. [less ▲]

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See detailOne-bit ADCs/DACs based MIMO radar: Performance analysis and joint design
Deng, Minglong; Cheng, Ziyang; Wu, Linlong UL et al

in IEEE Transactions on Signal Processing (2022), 70

Extremely low-resolution (e.g. one-bit) analog-to-digital converters (ADCs) and digital-to-analog converters (DACs) can substantially reduce hardware cost and power consumption for MIMO radar especially ... [more ▼]

Extremely low-resolution (e.g. one-bit) analog-to-digital converters (ADCs) and digital-to-analog converters (DACs) can substantially reduce hardware cost and power consumption for MIMO radar especially with large scale antennas. In this paper, we focus on the detection performance analysis and joint design for the MIMO radar with one-bit ADCs and DACs. Specifically, under the assumption of low signal-to-noise ratio (SNR) and interference-to-noise ratio (INR), we derive the expressions of probability of detection ( Pd ) and probability of false alarm ( Pf ) for one-bit MIMO radar and also the theoretical performance gap to infinite-bit MIMO radars for the noise-only case. We further find that for a fixed Pf , Pd depends on the defined quantized signal-to-interference-plus-noise ratio (QSINR), which is a function of the transmit waveform and receive filter. Thus, an optimization problem arises naturally to maximize the QSINR by joint designing the waveform and filter. For the formulated problem, we propose an alternating waveform and filter design for QSINR maximization (GREET). At each iteration of GREET, the optimal receive filter is updated via the minimum variance distortionless response (MVDR) method, and due to the difficulty in global optimality, an alternating direction method of multipliers (ADMM) based algorithm is devised to efficiently find a high-quality suboptimal one-bit waveform. Numerical simulations are consistent to the theoretical performance analysis and demonstrate the effectiveness of the proposed design algorithm. [less ▲]

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See detailJoint Design of Horizontal and Vertical Polarization Waveforms for Polarimetric Radar Via SINR Maximization
Cheng, Xu; Wu, Linlong UL; Ciuonzo, Domenico et al

in IEEE Transactions on Aerospace and Electronic Systems (2022)

For an extended target with different polarimetric response, one way of improving the detection performance is to exploit waveform diversity on the dimension of polarization. In this paper, we focus on ... [more ▼]

For an extended target with different polarimetric response, one way of improving the detection performance is to exploit waveform diversity on the dimension of polarization. In this paper, we focus on joint design of transmit signal and receive filter for polarimetric radars with local waveform constraints. Considering the signal-to-interference-plus-noise ratio (SINR) as the figure of merit to optimize, where the average Target-Impulse-Response Matrix (TIRM) within a certain Target-Aspect-Angle (TAA) interval is employed as the target response, the waveform is decomposed and then designed for both horizontal and vertical polarization segments, subject to energy and similarity constraints. An iterative algorithm is proposed based on the majorization-minimization (MM) method to solve the formulated problem. The developed algorithm guarantees the convergence to a B-stationary point, where in each iteration, optimal horizontal and vertical transmit waveforms are respectively solved by using the feasible point pursuit and successive convex approximation (FPP-SCA) technique. Experiment results show the effectiveness of the proposed algorithm, the robustness of the output SINR against the TAA change, and the advantages of polarization diversity and local design. [less ▲]

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See detailSpatial Spectrum Nulling for Wideband OFDM-DFRC System With Hybrid Beamforming Architecture
Wang, Bowen; Cheng, Ziyang; Wu, Linlong UL et al

in 2022 IEEE Wireless Communications and Networking Conference (WCNC) (2022)

This paper deals with the problem of the hybrid beamforming design of wideband orthogonal frequency division multiplexing (OFDM) dual-function radar-communication (DFRC) system, which is expected to ... [more ▼]

This paper deals with the problem of the hybrid beamforming design of wideband orthogonal frequency division multiplexing (OFDM) dual-function radar-communication (DFRC) system, which is expected to achieve a satisfactory user's spectral efficiency and form excellent space-frequency spectrum behavior as well as spatial nulls on the directions of strong signal-dependent interference (such as clutters) simultaneously. For such purpose, we formulate our problem by maximizing the communication spectral efficiency subject to the constraints of radar integrated sidelobe to mainlobe ratio (ISMR) and spatial spectrum nulling (SSN). Due to the fact that the analog beamformer for all subcarriers and digital beamformer for each subcarrier are simultaneously optimized in the wideband OFDM system, the resultant problem is difficult to solve. Towards that end, an efficient algorithm is devised based on the consensus alternating direction method of multipliers (CADMM) framework. Numerical simulation results demonstrate the superiority of the proposed hybrid beamforming algorithm. [less ▲]

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See detailThe Next Generation of Beam Hopping Satellite Systems: Dynamic Beam Illumination with Selective Precoding
Chen, Lin UL; Ha, Vu Nguyen UL; Lagunas, Eva UL et al

in IEEE Transactions on Wireless Communications (2022)

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See detailTransmit Beampattern Synthesis for Planar Array with One-bit DACs
Wei, Tong UL; Wu, Linlong UL; Alaeekerahroodi, Mohammad UL et al

Scientific Conference (2021)

Detailed reference viewed: 28 (8 UL)