In this paper, we present the design of a high-performance dual-linearly polarised broadband stacked patch antenna array for SATCOM on-the-move applications. The antenna has been designed to operate in the GHz frequency range, covering both the receiving and transmitting SOTM Ku bands, namely, GHz and GHz, respectively. The array, excited with a feeding system leveraging two perpendicular corporate feeding networks, enables electronically reconfiguration of two orthogonal linear polarisations, which can be combined to synthesise other polarisation states, such as circular. The proposed design targets of robustness, reliability and simplicity have been validated through experimental characterisation, showing a good agreement when compared against full-wave electromagnetic simulations.
Electronic beam scanning surpasses mechanical rotation in speed and maintenance, yet 2-D continuous electronic scanning around 0.2 THz remains challenging. This paper proposes combining slotted-waveguide frequency scanning with digital beamforming phased-arrays to realise 2-D continuous electronic scanning at 197-205 GHz. Frequency scanning employs alternating slot placement on a rectangular waveguide to broaden the scan range while achieving E-plane symmetry. Optimisation using an equivalent circuit model and power transmission method yields H-plane patterns with 20 dB grating lobe suppression and high main beam radiation efficiency. Phase scanning utilises unit aperture extension to suppress grating lobes even for element spacing much larger than a wavelength. Testing combines near-to-far field extrapolation with digital beamforming via a 'two-step feed line calibration', verifying phase-controlled scanning capability. According to the measurement results, the proposed antenna achieves a beam scanning range of 14.1 degrees & times; 8 degrees and exhibits main beam radiation efficiency of more than 86% across the entire bandwidth.
Accurate and efficient simulation of large-scale radome-enclosed antenna arrays is challenging in the fields such as radar and communication. The parallel multilevel fast multipole algorithm (MLFMA) is suitable for solving radiation problems of large-scale radome-enclosed antenna arrays. To enhance the efficiency and balance the workloads for the MLFMA, this paper presents a parallel MLFMA framework. The proposed algorithm creates multiple MLFMA octrees for different medium regions and waveport excitations. In the parallel computation of near-field interactions, an auxiliary octree is constructed to avoid the duplication of triangular integrals and employ the K-way approach to partition the workloads. In the computation of far-field interactions through evaluating the workloads related to each tree and dynamically partitioning the process groups, an adaptive partitioning strategy is designed to balance the workloads of multiple octrees, which reduces the communication traffic and achieves high parallel efficiency. Numerical results show that efficiencies of the parallel MLFMA are higher than 80% when the number of processes increases from 36 to 720.
This paper presents an ultra-wideband (UWB) antenna pair for 5G mobile terminals. The antenna pair is composed of two coupled-fed loop antennas with a common shorted branch, which achieves a compact size. The wideband operation is obtained by meticulously exciting two-loop modes. Due to the common shorted branch, a good isolation level (> 10 dB) is acquired. Based on four coupled-fed loop antenna pairs, an ultra-wideband 8 & times; 8 multiple-input multiple-output (MIMO) array with compact size is conducted and measured. The experimental results show that the MIMO array covers 3.3-7.8 GHz with a relative bandwidth of 81.08%, and the isolation between ports is better than 10 dB. In addition, the measured radiation pattern, total efficiency and ECCs (envelope correlation coefficients) are also discussed.
Radomes play a fundamental role in protecting antenna systems deployed in outdoor environments while preserving their electromagnetic performance. Due to their direct interaction with the radiated field, both structural and electromagnetic properties must be carefully engineered. This paper introduces a design methodology for advanced multilayer radomes intended for high-performance satellite communication systems, ensuring broadband transparency and compactness. As a case study, we consider several sub-bands spanning from 7.2 to 31 GHz and covering a broad range of incidence angles for both transverse-electric (TE) and transverse-magnetic (TM) polarizations. The proposed approach employs a particle swarm optimization algorithm to maximize transmission within the specified frequency bands by optimally adjusting layer thicknesses while accurately modelling the frequency-dispersive permittivity of the selected materials. This process yields a lightweight, high-transparency radome design suitable for multiband operation. The methodology was validated through full-wave simulations across six frequency bands using realistic dispersive materials. Results show excellent agreement between analytical and numerical models, with tolerance analysis confirming robustness against manufacturing deviations. The proposed framework demonstrates strong potential for the systematic design of next-generation multilayer radomes meeting the stringent requirements of modern satellite communication systems.
