Article
Geochemistry & Geophysics
Baocheng Zhang, Pengyu Hou, Jiuping Zha, Teng Liu
Summary: PPP-RTK combines PPP and RTK techniques, utilizes the IE-FDMA model to address integer ambiguity in GLONASS PPP-RTK, and deals with inter-frequency biases in various network configurations.
JOURNAL OF GEODESY
(2021)
Article
Remote Sensing
Safoora Zaminpardaz, Peter J. G. Teunissen, Amir Khodabandeh
Summary: The study assesses the standalone GLONASS RTK performance using both FDMA and CDMA signals, introducing new models for integer-estimable ambiguities. Different combinations of GLONASS signals are considered, with formal analysis presented for current and future ambiguity resolution and positioning.
Article
Engineering, Multidisciplinary
A. Khodabandeh, S. Zaminpardaz, N. Nadarajah
Summary: This paper investigates the ambiguity resolution performance of a dual-epoch phase-only model, showing that multi-GNSS integration enables near real-time centimeter-level phase-only positioning to be possible.
MEASUREMENT SCIENCE AND TECHNOLOGY
(2021)
Article
Engineering, Aerospace
A. Khodabandeh, P. J. G. Teunissen
Summary: This study aims to present full-rank models that can be used to identify integer-estimable ambiguity functions, thereby bringing the observation equations of frequency-varying carrier phase measurements into an IAR-applicable form.
NAVIGATION-JOURNAL OF THE INSTITUTE OF NAVIGATION
(2022)
Article
Geochemistry & Geophysics
Caoming Fan, Zheng Yao, Shijie Yun, Jianping Xing
Summary: This study aims to improve position accuracy and convergence speed by applying GNSS precise positioning technology to ground-based pseudolite systems. The research shows that TPBs are rather stable over time and do not need to be broadcast to users frequently.
JOURNAL OF GEODESY
(2021)
Article
Geochemistry & Geophysics
P. J. G. Teunissen, A. Khodabandeh
Summary: In this paper, the PPP-RTK theory is generalized to allow transmitters to transmit on different frequencies. Based on the constraints imposed on the admissible ambiguity transformations by PPP-RTK, a fundamental network+user condition is found that determines the possibility of PPP-RTK.
JOURNAL OF GEODESY
(2022)
Article
Engineering, Electrical & Electronic
Minh Q. Nguyen, Reinhard Feger, Jonathan Bechter, Markus Pichler-Scheder, Martin H. Hahn, Andreas Stelzer
Summary: The article presents a method using RDMA and DDMA to achieve MIMO functionality for FMCW radars, with advantages including improved range and reduced image signals. Various modulation techniques are used to enable simultaneous transmission from multiple antennas and balance performance in angular resolution, range, and velocity measurements. The proposed system is verified using measurement data on a prototype with three TX and four receiving antennas.
IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES
(2021)
Article
Engineering, Electrical & Electronic
Liangsen Zhai, Yulong Zou, Jia Zhu
Summary: This paper proposes the integration of an intelligent reflecting surface (IRS) into a wireless powered Internet of Things (IoT) network. It explores the use of Stackelberg game to solve the energy interaction problem among different operators. Three multiple access schemes are considered, and simulation results show the characteristics and advantages of each scheme.
IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS
(2023)
Article
Environmental Sciences
Dimitrios Psychas, Peter J. G. Teunissen, Sandra Verhagen
Summary: The use of single-receiver integer ambiguity resolution in precise point positioning (PPP-RTK) is crucial in reducing convergence time. The availability of more satellites and frequencies in global navigation satellite systems (GNSS) supports faster integer ambiguity resolution. The study of Galileo-based PPP-RTK ambiguity resolution and positioning convergence shows the significant impact of frequency separation on performance.
Article
Geochemistry & Geophysics
A. Khodabandeh
Summary: The study aims to develop a framework for generating multi-epoch, single-station corrections to enable PPP-RTK users to time-predict corrections subject to delay. The analytical study shows that the number of satellites and frequencies work together to increase correction latency while ensuring successful single-receiver ambiguity resolution.
JOURNAL OF GEODESY
(2021)
Article
Remote Sensing
Adria Rovira-Garcia, Jose Miguel Juan, Jaume Sanz, Guillermo Gonzalez-Casado, Javier Ventura-Traveset, Luigi Cacciapuoti, Erik Schoenemann
Summary: The study proposes a strategy to estimate satellite and receiver clock offsets using unambiguous carrier phase measurements, aiming to reduce day-boundary discontinuities (DBDs) in products within the International GNSS Service (IGS). By comparing clock estimations with those from different analysis centers (ACs), the study shows improvements in clock estimates with the use of continuous and unambiguous carrier phase measurements, benefiting the statistical characterization of long-term phenomena correlated with on-board clocks.
Article
Engineering, Electrical & Electronic
Yibin Wan, Bo Liu, Yaya Mao, Jianxin Ren, Rahat Ullah, Shuaidong Chen, Xiangyu Wu, Yu Bai, Xiumin Song, Rong Tang, Haojing Zhang, Yongfeng Wu
Summary: This paper proposes a novel chaotic power division multiplexing (CPDM) for secure optical multiple access, which can improve spectral efficiency and user capacity, and ensure information security. Experimental results show that the system can achieve high spectral efficiency and large traffic capacity, and serve more users.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Engineering, Multidisciplinary
Wenju Fu, Jin Wang, Lei Wang, Ruizhi Chen
Summary: This study proposes a Kalman filter-based online fractional cycle bias (FCB) determination method for real-time integer ambiguity resolution in satellite clock estimation. By smoothing the float wide-lane ambiguity and implementing quality control procedures, the method improves estimation accuracy and convergence. Validation results show significant improvement in real-time positioning accuracy.
Article
Remote Sensing
Yumiao Tian, Zhifang Liu, Kaige Li
Summary: This study implements the Markov chain Monte Carlo (MCMC) method to refine the sample distribution in differential code phase biases (DCPB) estimation for GLONASS-only single-epoch observations. The experiment results show that the MCMC method enables GLONASS-only FDMA ambiguity fixing and achieves single-epoch precise positioning, even when the baseline and differential inter-frequency biases (DIFB) are unknown in advance.
Article
Engineering, Electrical & Electronic
Zidong Wu, Linglong Dai
Summary: Spatial division multiple access (SDMA) is essential for improving spectrum efficiency in multi-user MIMO communications. However, the traditional SDMA heavily relies on angular orthogonality in the far field and fails to fully utilize spatial resources in the distance domain. In this paper, we propose location division multiple access (LDMA) to enhance spectrum efficiency by exploiting extra spatial resources in the near field. The LDMA approach leverages near-field beam focusing and provides a codebook design method for LDMA communications using a uniform planar array.
IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS
(2023)
