Mobile Satellite Communications Research Articles

Efficient and quantum‐secure authenticated key exchange scheme for mobile satellite communication networks

SummaryThe mobile satellite communication (MSC) system is a vital communication method in which mobile users and network control centers connect via satellites. Since the satellite's communication is wireless, communication security is a critical factor to ensure accountable communication. Key exchange and authentication (KEA) mechanism is widely used to achieve data security for data transmitted in an insecure or open channel. Different authentication systems are suggested in the last many years to establish safe communication, whereas most existing security protocols are based on factorization or discrete logarithm. However, these systems are no longer reliable by Shor's algorithm as any discrete logarithm and factorization can be resolved in polynomial time on quantum computers. Thus, developing a quantum secure KEA protocol for MSC systems is necessary. In this direction, recently a ring learning with an error‐based KEA technique is proposed to ensure a quantum‐safe environment. This scheme is quantum‐safe and satisfies desirable security attributes but has low efficiency in computation and communication. Moreover, establishing a secure session requires six communications among involved entities. As a result, replay attack detection at an early stage is not possible for the central authority (server), which could delay the server response, and the adversary gets the advantage of drawing a denial of service scenario for authorized entities. We propose a lattice‐based KEA protocol for the MSC system to improve computation, communication efficiency, and early‐stage replay attack detection. The security analysis of the proposed scheme is presented in the random oracle model. Calculation of performance is also presented to observe advantages in computation and communication overhead.

Cryptanalysis with improvement on lattice‐based authenticated key exchange protocol for mobile satellite communication networks

SummaryThe mobile satellite communication (MSC) system represents a crucial means of communication, facilitating connections between mobile users and network control centres through satellites. Given the wireless nature of satellite communication, ensuring communication security is paramount for maintaining accountability. Key exchange and authentication (KEA) mechanisms are commonly employed to secure data transmitted over insecure or open channels. Developing a lattice‐based KEA protocol for MSC systems is imperative to achieve both quantum security and efficient communication. In this direction, Yadav et al. devised ring learning with an error‐based KEA technique to ensure a quantum‐safe environment. Their scheme is quantum‐safe and satisfies desirable security attributes but has low efficiency in computation. Moreover, we have identified that their scheme is susceptible to denial of service attack and session key established at user and NCC ends is different. To overcome the flaws of Yadav et al., we propose a lattice‐based KEA protocol for the MSC system to improve computation efficiency, and get resistance against key mismatch attack. The security analysis of the proposed scheme is presented in the random oracle model. Comparative study is also presented to observe advantages in computation efficiency.

Design of a transmissive dual-frequency polarization rotator for linearly polarized electromagnetic wave

This paper presents the design of a transmission-type dual-frequency polarization rotator for linearly polarized electromagnetic wave. The rotator facilitates polarization conversion for incident waves at any azimuth angle ϕ at two specific frequency points, resulting in a transmission wave with a counterclockwise rotation of 2ϕ. The proposed polarization rotator structure comprises three metal layers separated by two dielectric substrates. It includes two large rectangular metal patches positioned orthogonally along the x- and y-axes, respectively, as well as two small rectangular metal patches also positioned orthogonally along the x- and y-axes, respectively. The upper and lower metal layers act as the receiving and radiation ends, respectively. The transmitting and receiving ends are interconnected through coaxial metal holes. Remarkably, polarization conversion efficiencies exceeding 0.95 and 0.94 at 12 and 17 GHz, respectively, are achieved, and these high conversion efficiencies remain consistent as the azimuth angle of incidence changes. Furthermore, experimental results obtained from fabricated samples align well with the simulation ones, thus validating the effectiveness of the proposed polarization rotator. The proposed transmissive dual-frequency polarization rotator exhibits good practical application prospects in mobile satellite communications, GNSS, WLAN, etc.

Wideband phased array design using hairpin ring resonator (HRR) and DGS for double band-notched performance

In this paper, a wideband Vivaldi phased array with double band-notched performance for radio astronomy is proposed. To address the issues of radio frequency interference from 5 G mobile communication (4.8–5 GHz) and C-band satellite communication (5.9–6.5 GHz) in radio astronomy system, the hairpin ring resonator (HRR), defected ground structure and λ/2 shorted-circuit stub are utilized together to realize the double notched bands with different bandwidth. The resonate mechanism of the proposed HRR is widely investigated, which exhibits independent and controllable resonances. Meanwhile, λ/2 shorted-circuited stub is adopted for the band notched performance. As the current on the stub is induced along the shorted via to the ground, without participating in radiation, thus the notched frequency is not affected by the scan angle. With these novel and dedicated design, the proposed phased array performs double band-notched performance with high skirt selectivity and deep suppression, within the notched band the maximum rejection level is better than 22.7 dB. This is the first work to implement double notched bands in phased array to the authors’ best knowledge. Finally, a prototype composed of 8 × 9 elements is fabricated and measured. The measurements agree well with the simulated ones.

Engineering planar antenna using geometry arrangements for wireless communications and satellite applications

A triple-band microstrip patch antenna designed for the IEEE 802.16e WiMAX, IEEE 802.11a WLAN, C-band downlink communications, and Ku-band radar recent applications is suggested in this article. The planned antenna operates at 2.45, 6, and 14 GHz resonant frequencies. The antenna fulfilled triple-band physical characteristics covering industrial, scientific, and medical (ISM) bands between (2.1–2.8) GHz; (5.6–6.5) GHz for wireless local area network (WLAN) or ultra-wideband (UWB) services; and 12.7–16 GHz for future two-way 5G:6G either broadcasting or mobile satellite communications. To achieve better return loss performance, parametric studies are carried out using Microwave Studio (CST MWS). The proposed antenna is designed on the FR4 as a hosting medium of total size 46 × 38 × 1.6 mm3, combined with a planar transmission line (T.L.) feed and defected ground structure (DGS). The simulated antenna’s input reflection coefficient (S11) results and the far-field measurements show good agreement. The fabricated prototype achieves peak gain values of 2.8, 3.8, and 4.7 dBi, respectively, and bidirectional radiation characteristics. A comparative study with other recent publications is implemented to validate the consistency of the design.

Dual-Band MIMO Antenna with Four CPW Elements using Polarization Diversity for 5G Mobile Communication Networks and Satellite

In this paper, a novel design of compact quad-element MIMO (Multiple Input Multiple Output) antenna for 5G communication networks and satellites is proposed. The four similar elements of this antenna are placed perpendicularly to each other on a 40x40 mm2 FR4 substrate. Each element is fed by a CPW (coplanar waveguide) line. Two slits and an I-shaped slot are etched into the patch, and by varying their parameters; a good matching is achieved in the lower (4.9 GHz) and upper (17 GHz) frequency bands. However, 25 and 30 dB isolations are attained in the lower and upper bands, using the polarization diversity technique and adding stubs on the ground plane. A prototype of the proposed antenna is fabricated and measured. Moreover, the performance of the MIMO antenna is studied in terms of ECC (envelope correlation coefficient), DG (diversity gain), TARC (total active reflection coefficient), realized gain, efficiency, and radiation pattern, validated with the measured results, and showed a good agreement.

Design, Modelling and Research of an Antenna System for Transmitting and Receiving Information in Satellite Systems

Abstract The work deals with the design, modelling and research of an antenna system for transmitting and receiving information in satellite systems. It was revealed that this antenna array with a transmitter of 85 dBWt is guaranteed to solve the target problem of providing mobile satellite communications with both one global beam and a plurality of beams with a width of 0,7 × 0,7°. It should be added that the advantage of forming multiple beams compared to a global beam with a single phased antenna array is: higher data rate, relatively low requirements for antenna systems of ground stations, greater noise immunity of the radio link, the ability to dynamically control the signal power in each beam.

The Fluctuating Two-Ray Fading Model With Independent Specular Components

We introduce and characterize the independent fluctuating two-ray (IFTR) fading model, a class of fading models consisting of two specular components which fluctuate <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">independently</i> , plus a diffuse component modeled as a complex Gaussian random variable. The IFTR model complements the popular fluctuating two-ray (FTR) model, on which the specular components are fully correlated and fluctuate <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">jointly</i> . The chief probability functions of the received SNR in IFTR fading, including the PDF, CDF and MGF, are expressed in closed-form, having a functional form similar to other state-of-the-art fading models. Then, the IFTR model is empirically validated using multiple channels measured in rather diverse scenarios, including line of sight (LOS) millimeter-wave, land mobile satellite (LMS) and underwater acoustic communication (UAC), showing a better fit than the original FTR model and other models previously used in these environments. Additionally, the performance of wireless communication systems operating under IFTR fading is evaluated in closed-form in two scenarios: ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">i</i> ) exact and asymptotic bit error rate for a family of coherent modulations; and ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ii</i> ) exact and asymptotic outage probability.

Control-Oriented Power Allocation for Integrated Satellite-UAV Networks

This letter presents a sensing-communication-computing-control (SC3) integrated satellite unmanned aerial vehicle (UAV) network, where UAVs are equipped with sensors, mobile edge computing (MEC) servers, base stations and satellite communication modules. Like a nervous system, this integrated network is capable of organizing multiple field robots in remote areas, so as to perform mission-critical tasks which are dangerous for humans. Aiming at activating this nervous system with multiple SC3 loops, we present a control-oriented optimization problem. Different from traditional studies which mainly focused on communication metrics, we address the power allocation issue to minimize the sum linear quadratic regulator (LQR) control cost of all SC3 loops. Specifically, we show the convexity of the problem and reveal the relationship between the optimal transmit power and intrinsic entropy rates of different SC3 loops. For the assure-to-be-stable case, we derive a closed-form solution for ease of practical applications. After demonstrating the superiority of the control-oriented power allocation, we further highlight its difference from the classic capacity-oriented water-filling method.

Additively Manufactured Half-Gutman Lens Antenna for Mobile Satellite Communications

In this letter, we present an additively manufactured half-Gutman lens antenna operating at 30 GHz. The hemispherical lens allows for a compact beamformer while maintaining the wide scanning capabilities of Gutman lenses. This solution further enables to better integrate the feed system when compared to a more conventional half-Luneburg lens antenna design as the focal arc is moved inside the lens. The graded-index of the lens is implemented with a periodic structure arranged in a body-centred cubic (BCC) lattice. We demonstrate that the BCC structure provides attractive properties for the design of inhomogeneous dielectric lenses. Importantly, the BCC structure can be used to alleviate the manufacturing constrains compared to conventional periodic structures. The lens is fed by a dielectric-loaded square waveguide. The proposed antenna produces a directive beam with a simulated and measured peak gain of 26.2 and 25.3 dBi. The antenna can steer its beam in a 50 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^\circ$</tex-math></inline-formula> range in elevation with measured scan loss and sidelobe levels below 1 dB and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$-$</tex-math></inline-formula> 10 dB, which agree with the simulated values. The measured cross polarization discrimination is better than 20 dB. The proposed antenna is intended for the ground segment of the emerging low-Earth-orbit satellite communication applications.

A compact channel patch antenna with reconfigurable circularly polarized pattern for mobile satellite communications

A compact dual-band circularly polarized antenna with a characteristic of pattern reconfiguration is proposed for S-band satellite handsets. The antenna works as a patch antenna in a channel shape with no ground beneath reaching an overall size of 0.55λ × 0.14λ × 0.1λ. The dual-band performance is realized through multi-branch slots of the patch. The antenna mainly consists of a channel metal patch, a channel dielectric, and a simple feeding network. The overall shape of slot can be changed by the PIN diode on the patch to adjust the surface current direction, which in turn achieves 180° switching of the left-hand circularly polarized radiation beam direction. In addition, by combining the quadrifilar helical antenna, which is switchable in the end-fire beam direction, the designed antenna can realize the switching of four main beam directions to achieve 360° 3D spatial coverage. The proposed antenna is fabricated and measured to verify the proposed design. The test results show that the designed antenna obtains circularly polarized radiating characteristics in S-band with the center frequency of 1.98 GHz and 2.2 GHz, and the test results and simulation results are basically consistent, which indicates the superior performance of the designed antenna.

Effects of packing fraction, lattice vibration, and bond valence on the microwave dielectric properties of low-εr garnet-type Ca3Sc2Ge3O12 ceramics

A low relative permittivity (εr) can effectively reduce the signal delay of microwave components. In this study, cubic garnet-type Ca3Sc2Ge3O12 (CSG) ceramics were prepared using a traditional solid-state reaction method. The CSG ceramic exhibited a single phase (space group: Ia-3d) with a cubic garnet-type structure. The ceramic sintered at 1375 ​°C had the best topography and presented the optimal microwave dielectric properties (εr ​= ​7.08, Q×f ​= ​34697 ​GHz, and τf ​= ​−20.37 ​ppm/°C). Furthermore, the relationship between the Q×f values and the packing fraction and covalence was discussed, and the effect of lattice vibrations on the internal dielectric loss of CSG was investigated. The internal relationship between the dielectric permittivity and lattice vibration polarization was analyzed. The bond valence of the CSG material significantly affected the τf value. The excellent microwave dielectric performance indicated that CSG ceramics are suitable for use in mobile communication base stations, satellite navigation, and radar communications.

Cyber-Physical Attack Using High Power RF in Havana, Cuba

Abstract: Global communications have relied heavily on fiber-optic cables. Satellite communications have become the norm for areas that are not highly populated or easily reached by conventional wires. The availability and use of satellite communications systems have had a limited market; with this limitation, the need for open development of each vendor's software never gained traction. This led to weaknesses not being discovered until a flaw was made public in a systems breach that affected the end users. Wireless communications that rely on microwaves lead to the use of malware to provide an override to normal operations of the equipment. As the issue of Stuxnet would allow for the override of the safety settings of satellite terminals, the malware could even be deployed remotely through a system update. The weaponization of such systems is now a point of concern. Previous studies have shown that naval satellite communications systems can be a weapon by removing the software power limitations McKay, R. W 2021 [15]. As satellite systems on ships can be larger due to being fixed, transmission power generation may be more significant. This study considers the land-based mobile systems deployed against any target and quickly dismantled and removed. Can land-based mobile satellite communication systems affected by Stuxnet or manually altered yield the same power output, and at what range will it affect human tissue? This is believed to be the case with the ongoing investigation. The survey results showed that mobile equipment could be dangerous to human tissue at distances easily achieved by mobile terminals, especially if the target is a fixed location like a building with large glass windows that R.F. power can penetrate easily

Dual Location Area Based Distributed Location Management for Hybrid LEO/MEO Mega Satellite Networks

Location management is the basis for ensuring service continuity in low earth orbit (LEO) satellite mobile communication systems. The dual mobility of LEO satellites and mobile users triggers frequent location update procedures, which will increase the network location management overhead and bring great challenges to network location management, especially in the mega satellite networks. In this paper, we propose a location management technology solution for mega satellite networks, including location management architecture, location area design, location update, and paging procedures. A medium earth orbit (MEO) satellite-assisted location management architecture is proposed to improve the efficiency of location management. It extends the location management control plane from the ground to space and adopts a distributed location management mechanism. A dual location area, including the satellite location area and user location area, is designed to balance the network location update and paging overhead. Based on the dual location area, we systematically design low-overhead location update and paging procedures. Simulation results have verified that the proposed location management technology solution can reduce the total location management overhead and delay by at least 45.8% and 20.8%, respectively.

Highly compact UWB-BPF with a wide notch-band using a rectangular ring structure and two Y-shaped open stub resonators

A miniaturized ultra-wideband bandpass filter (UWB-BPF) with a high rejection notched band is proposed in this article. It is composed of a rectangular ring with two grounded vias, a microstrip line with two open radial stubs, a pair of interdigital feedlines with two lumped capacitors and two open-loaded Y-shaped stub resonators (YSSR), as well as a defected ground structure (DGS). This filter was simulated and fabricated by using a practical printed circuit board (PCB) process with the substrate of FR4. The measurement results agree well with the simulation data. The measured 3-dB passbands cover 2.73–4.36 and 6.82–11.78 GHz, the in-band insertion loss is less than 1.13 dB except at the edges of the bands, and the return loss is better than 10 dB. It is found that the filter’s lower and upper transmission zeros occur at 0.8 and 13.95 GHz with the magnitudes of −87.2 and −45.6 dB, respectively. This makes the filter exhibit high selectivity with the steep skirt characteristics. It is also worth noting that the proposed filter possesses a wide 10-dB notch band ranging from 4.87 to 6.93 GHz with the highest rejection of 46.3 dB at 5.9 GHz. This feature can effectively and simultaneously inhibit the unwanted signals coming from the C-band 5G mobile communication, 5-GHz WiFi, WLAN, and 6-GHz satellite systems. Furthermore, the presented filter is highly compact with the dimensions of 13.2 mm × 11.8 mm and has a very wide upper stopband spanning from 13.4 to 28 GHz with rejection of 20 dB or higher.

Physical Layer Security in Interference Limited Land Mobile Satellite Communication Systems: Safeguarding Data Transmission

This paper focuses on evaluating the secrecy performance of a downlink land mobile satellite (LMS) system. The system faces the challenge of providing secure communication between a satellite and a legitimate user while an eavesdropper is present on the ground. Additionally, co-channel interference signals at the user's destination are considered. To address these issues, the study proposes a novel approach that utilizes Shadowed-Rician fading channels for satellite links and Nakagami-m fading for interfering terrestrial links. The main objective is to enhance the physical layer security of Interference-Limited Land Mobile Satellite Communication Systems. The approach incorporates advanced signal processing, beamforming, and artificial noise techniques to effectively manage interference. Encryption, authentication mechanisms, and intelligent power control strategies are implemented to protect transmitted data and optimize signal strength while reducing the risk of interception by potential eavesdroppers. Through comprehensive simulations, the proposed approach is thoroughly evaluated, demonstrating its effectiveness in achieving improved secrecy performance and increased resilience against security threats. The findings highlight the potential for its application in secure satellite communication systems operating in interference-constrained environments.

Design of GHz Mechanical Nanoresonator with High Q-Factor Based on Optomechanical System

Micro-electromechanical systems (MEMS) have dominated the interests of the industry due to its microminiaturization and high frequency for the past few decades. With the rapid development of various radio frequency (RF) systems, such as 5G mobile telecommunications, satellite, and other wireless communication, this research has focused on a high frequency resonator with high quality. However, the resonator based on an inverse piezoelectric effect has met with a bottleneck in high frequency because of the low quality factor. Here, we propose a resonator based on optomechanical interaction (i.e., acoustic-optic coupling). A picosecond laser can excite resonance by radiation pressure. The design idea and the optimization of the resonator are given. Finally, with comprehensive consideration of mechanical losses at room temperature, the resonator can reach a high Q-factor of 1.17 × 104 when operating at 5.69 GHz. This work provides a new concept in the design of NEMS mechanical resonators with a large frequency and high Q-factor.

Compact Quad-Port MIMO Antenna with Ultra-Wideband and High Isolation

In this paper, we propose a compact and highly isolated four-port ultra-wideband MIMO antenna. The antenna elements achieve broadband characteristics by etching a metamaterial structure on the radiating patch and stepping the coplanar waveguide feed. The test results show that the unit antenna can operate from 1.8 GHz to 16.38 GHz with an absolute bandwidth of 14.58 GHz and a relative bandwidth of 160.4% with good radiation properties and gain. After that, a compact four-cell ultra-wideband MIMO antenna is designed by using polarization diversity technology with an overall size of 51.2 mm × 51.2 mm × 1.524 mm. The MIMO antenna can operate from 1 GHz to 17 GHz with an absolute bandwidth of 16 GHz and a relative bandwidth of 177.78%. To reduce the coupling between cells, four angled slits are etched on the common ground to improve the isolation of the MIMO antennas to 27.8 dB. The performance parameters of the proposed MIMO antennas are further validated through simulation analysis and measurements. Moreover, the diversity properties of MIMO antennas are analyzed in detail, demonstrating the applicability of the proposed antennas in UWB communication systems, which can also be used for satellite mobile communications and satellite fixed communication services.

Physical random access signal design for 5G mobile satellite communication systems

In view of the distinctive characteristics of satellite communication, the physical random access signals used in the terrestrial mobile communication system have to be modified or redesigned for the satellite communication system. In this paper, we boost the random access signal energy by repeating the short Zadoff–Chu (ZC) sequence based preamble signal used in the terrestrial system. Different long ZC sequences are used to scramble this cascaded sequence to distinguish different random access signals for multiple random access user equipments. For correlation performance optimization, properties of the roots for both the short and long ZC sequences are mathematically analyzed and derived. Finally, we illustrate how to construct a root set for these different long ZC sequences based on the obtained propositions in a practical way. This analytical framework provides a useful insight into ZC sequence-based random access signal design and performance analysis in mobile satellite communication systems.

Tunability Behavior of (Ba, Ca)(Zr, Ti)O Ceramic Capacitors Powered by Thermally Induced Phase Transitions With Applications to Nonlinear Transmission Lines

Ferroelectric ceramics with low loss dielectric, high permittivity, and nonlinear behavior are essential in capacitive nonlinear transmission lines (NLTLs) for radio frequency (RF) generation. NLTLs have the potential to generate soliton waves for high-power microwave (HPM) applications in mobile defense platforms and satellite communications. In this work, we synthesize, characterize, and investigate the nonlinear behavior of (Ba,Ca)(Zr,Ti)O3 ceramics system to be applied as nonlinear elements in capacitive NLTLs. The ceramics were structurally and microstructural characterized. Anomalies in dielectric and pyroelectric curves access the temperatures of phase transitions. The permittivity tunability was studied as a function of electric field and frequency in temperatures near phase transitions. The phase transitions of materials are identified by temperature where the permittivity and percentage of nonlinear tunability factor (NTF) are higher, which are required to produce RF on NLTLs.