Satellite Communication Applications Research Articles

Dual-Polarization Conversion and Coding Metasurface for Wideband Radar Cross-Section Reduction

Modern stealth application systems require integrated meta-devices to operate effectively and have gained significant attention recently. This research paper proposes a 1-bit coding metasurface (CM) design. The fundamental component of the proposed CM is integrated to convert linearly polarized incoming electromagnetic waves into their orthogonal counterpart within frequency bands of 12.37–13.03 GHz and 18.96–32.37 GHz, achieving a polarization conversion ratio exceeding 99%. Furthermore, it enables linear-to-circular polarization conversion from 11.80 to 12.29, 13.17 to 18.44, and 33.33 to 40.35 GHz. A second element is produced by rotating a fundamental component by 90°, introducing a phase difference of π (pi) between them. Both elements are arranged in an array using a random aperiodic coding sequence to create a 1-bit CM for reducing the radar cross-section (RCS). The planar structure achieved over 10 dB RCS reduction for polarized waves in the frequency bands of 13.1–13.8 GHz and 20.4–30.9 GHz. A prototype was fabricated and tested, with the experimental results showing a good agreement with the simulated outcomes. The proposed design holds potential applications in radar systems, reflector antennas, stealth technologies, and satellite communication.

Design of a 3-Bit Circularly Polarized Reconfigurable Reflectarray

In this paper, a 3-bit circularly polarized reconfigurable reflectarray is proposed. The array consists of 64 units in an 8 × 8 configuration, with each unit containing a circular metal patch loaded with phase-delay lines and eight PIN diodes. To independently control each unit, a corresponding DC control circuit was designed and tested with the array. In the bandwidth of 3.43–3.71 GHz, the circularly polarized reconfigurable reflectarray achieved a gain of 16 dB, an aperture efficiency of 27%, an axial ratio of ≤3 dB, an operating bandwidth of 8%, and a beam scanning range of ±60°. The circularly polarized reconfigurable reflectarray can also achieve a good dual-beam radiation performance after testing. The 3-bit circularly polarized reconfigurable reflectarray proposed in this paper offers several advantages, including low loss, high aperture efficiency, a wide beam scanning range, and excellent stability in wide-angle oblique incidence. It has potential applications in low-cost phased array, satellite communications, and deep space exploration.

Wideband Via-Less Reconfigurable Reflection and Transmission Linear-Circular / Linear-Cross Polarizer for Vehicular Satellite Communication Applications

Wideband Via-Less Reconfigurable Reflection and Transmission Linear-Circular / Linear-Cross Polarizer for Vehicular Satellite Communication Applications

A Dual-Band Wearable Antenna for X and Ku Frequency Bands for Satellite Communication Applications.

In the present research, a novel 3 cut-pentagon dual-band antenna design has been introduced, and its attributes and performance are enhanced through the use of a specialized substrate called "Jeans" with a permittivity of 1.7. The conducting element employed is copper tape. The design and study of a dual-band wearable antenna optimized for X and Ku frequency bands, specifically tailored for satellite communications applications. The antenna is engineered to offer reliable and efficient performance within the X-band (6.31 GHz) and Ku-band (8.07 GHz) and extended resonant frequency 12.118GHz facilitating seamless connectivity in satellite communication networks. The board size is 43x25.5 mm^2. The Bandwidth for the first band of the suggested antenna is 37.58% for the frequency range between 5.87 GHz. To 8.587 GHz and the bandwidth for the second band is 12.85% for the frequency range 11.447 GHz to 13.02 GHz. The dual-band wearable antenna, which operates in two frequency bands, is created and simulated using CST software

Two-dimensionally high AR performance beam scanning utilizing randomly-rotated single-PIN-diode elements for circularly-polarized programmable metasurface

In this paper, we introduce a novel technique that utilizes randomly rotated elements (RREs) for the cross-polarization and axial ratio (AR) control of a circularly polarized programmable metasurface (CPPMS). We evaluate the CPPMS performance by comparing RREs layout with uniform elements (UEs) layout, and analyze far-field radiation parameters for 50 groups of CPPMS with different RREs layouts. Simulation results demonstrate consistent and improved performance across various RREs layouts, showcasing reduced cross-polarization and enhanced AR beamwidth. To validate these findings, we design a 1-bit CPPMS in Ku-band comprising 20 × 20 elements with the optimal RREs layout, and conduct measurements in an anechoic chamber. The CPPMS prototype achieves high gain (22.34 dBi), low cross-polarization (-20.5 dB), and a narrow 3 dB AR beamwidth (8.93°). Notably, it offers wide-angle beam scanning capabilities of up to ±60°. The gain bandwidth at -3 dB ranges from 14.54 to 16.65 GHz, with a relative bandwidth of 7.3%, while the 3 dB AR bandwidth extends from 14.24 to 16.07 GHz. Consequently, the proposed 1-bit CPPMS exhibits high-performance two-dimensional AR beam scanning, presenting promising applications in satellite communications.

Split ring resonator geometry inspired crossed flower shaped fractal antenna for satellite and 5G communication applications

This work suggests a fractal antenna in the shape of a crossed flower with a split ring resonator geometry. This suggested antenna serves the Sub-6 GHz 5G and satellite repeater applications for wireless devices operating in the frequency range of 4.01–4.82 and 7.6–7.94 GHz, respectively. The suggested antenna's performance parameters have been empirically confirmed by creating a printed prototype. The antenna geometry is based on a lower-cost FR4 substrate and consists of a mix of crossed floral square-shaped split-ring resonators organized in a Minkowski fractal configuration. A thorough examination of both manufactured and simulated antennas is conducted to demonstrate the uniqueness and edge over traditional dual-band antennas. The suggested fractal antenna's overall physical dimensions measure 0.90λ x 0.96λ at a lower resonant frequency. The response of the unit cell antenna is recorded when Split Ring Resonators are grouped in a fractal antenna with a flower shape. The measured findings verify that the proposed and constructed antenna has an electrical impedance bandwidth of −10 dB at lower frequency band (18.80 %, 4.01–4.82 GHz) and upper frequency band (4.41 %, 7.6–7.94 GHz) of −10 dB. The simulated and fabricated prototypes exhibit good agreement with respect to the stable gain and radiation patterns. Because of its consistent radiation efficiency in the realized resonating bands, the suggested prototype is a strong contender for 5G Sub-6 GHz and X band satellite applications.

A Four-Port Dual-Band Dual-Polarized Antenna for Ku-Band Satellite Communications

This paper presents the development of a four-port dual-band dual-polarized antenna for transmitting/receiving (Tx/Rx) applications in Ku-band satellite communications. The antenna consists of two antenna elements sharing a common radiating aperture, a low-band element formed by an L-probe proximity-fed square-ring radiator for operation at the Rx band of 10.7–12.75 GHz, and a high-band element realized by a stacked-patch radiator for operation at the Tx band of 13.75–14.5 GHz. Within a compact multilayer structure, the antenna achieves wide dual-band operation, with each band having the ability to simultaneously operate with dual polarization. An antenna prototype is fabricated and tested to verify its performance. The experimental results show that the proposed antenna achieves an impedance bandwidth of 9.28–12.96 GHz (13.21–15.32 GHz), an isolation value between two orthogonal polarizations of 12 dB (12.4 dB), and a peak gain of 6.63 dBi (5.42 diBi) at the low band (high band). Tx/Rx isolation of more than 14 dB is achieved in both the Rx band and Tx band.

A Multiband and Multifunctional Metasurface for Linear and Circular Polarization Conversion in Reflection Modes

Multifunctional integrated meta-devices are the demand of modern communication systems and are given a lot of attention nowadays. Most of the research has focused on either cross-polarization conversion (CPC) or linear-to-circular (LP–CP) conversion. However, simultaneously realizing multiple bands with good conversion efficiency remains crucial. This paper proposes a multiband and multifunctional dual reflective polarization converter surface capable of converting a linearly polarized (LP) wave into a circularly polarized (CP) wave, in frequency bands of 12.29–12.63 GHz, 16.08–24.16 GHz, 27.82–32.21 GHz, 33.75–38.74 GHz, and 39.70–39.79 GHz, with 3 dB axial ratio bandwidths of 2.7%, 40.15%, 14.6%, 13.76%, and 0.2%, respectively. Moreover, the converter is capable of achieving CPC with a polarization conversion ratio (PCR) that exceeds 95%, within the frequency ranges of 13.10–14.72 GHz, 25.43–26.00, 32.46–32.56 GHz, and 39.14–39.59 GHz. In addition, to identify the fundamental cause of the CPC and LP–CP conversion, a comprehensive theoretical investigation is provided. Furthermore, the surface current distribution patterns at different frequencies are investigated to analyze the conversion phenomena. A sample prototype consisting of 20 × 20 unit cells was fabricated and measured, verifying our design and the simulated results. The proposed structure has potential applications in satellite communications, radar, stealth technologies, and reflector antennas.

Evaluation of rainfall rates and rain-induced signal attenuation for satellite communication in the South-South Region of Nigeria

Rain fade causes signal attenuation which can relatively results in signal quality performance degradation, increased pathloss and coverage area reduction in satellite communication networks, most especially in the tropics and at higher operational frequencies above 10GHz. Analysis of rain attenuation provides useful insight for satellite communication engineers for efficient network planning and design within the region of study. Hence this paper presents threeyear analysis of signal-induced attenuation in the South-South States of Nigeria for the cities of Port-Harcourt, Uyo, Calabar and Eket, whose terrain characteristics could be generalized to represent urban, sub-urban and rural terrains in Nigeria. The International Telecommunications Union Radio-wave propagation (ITU-R P618-13) model was used to estimate the long-term rain attenuation at 10GHz, 20GHz and 30GHz for satellite communication applications. Results obtained at 10GHz, 20GHz and 30GHz operational frequencies show that at high frequency, rain fade can cause signal attenuation levels in the south-south region of Nigeria. In all, Calabar recorded the highest rain rate and corresponding highest attenuation level of 96.13dB at 30GHz compared to 50.29dB at 20GHz for the period under review.

A simplified and efficient approach for designing microstrip bandpass filters: Applications in satellite and 5G communications

The C-band is extensively utilized in aviation radars and satellite communications (Satcom). Bandpass filters (BPFs) are crucial components in microwave systems operating within this frequency range. Therefore, it is important to develop a straightforward and effective method for designing BPFs with desired response characteristics. Currently, the prevailing approach for designing wideband microstrip BPFs involves employing multiple microstrip resonators and empirical techniques. However, some of these approaches lack comprehensiveness and a systematic design process. The design steps used for a specific type of microstrip filter with a particular cut-off frequency may not be directly applicable to developing a different filter with a distinct cut-off frequency. Conversely, having a systematic design process and software that can generate filter structures based on the filter order and response characteristics provides significant advantages in designing LC filters. Therefore, if we can design an LC filter with the desired response using conventional methods and subsequently convert it to a microstrip filter, we can achieve a more systematic design approach. The present paper proposes an innovative method to convert LC bandpass filters obtained using classical functions such as Elliptic, Butterworth, Chebyshev, and Bessel functions into microstrip BPFs. The designed microstrip BPFs offer a simple and repeatable design process and possess the flexibility to adjust the working frequency by employing a specific scaling factor. This adaptability makes the designed microstrip BPFs suitable for various applications, including Satcom and 5G systems.

A reconfigurable switching diode loaded patch antenna for S, C, X, Ku, and K bands applications

A reconfigurable patch loaded via a switching radio frequency (RF) diode has been designed, investigated, and fabricated. The fabricated microstrip is able to adjust among several frequencies. A spectrum analyzer is used to test and measure different modes of operations. The proposed antenna is offered a new solution of uncomplicated and incomplex design via eliminating the biasing circuit while maintaining the finest performance. Two fast-switching diodes have been inserted as a new electrical reconfiguration technique. Thus, the suggested antenna is skilled to function in different bands. An ultra-small size antenna of 31×21 mm2 has offered various operating frequencies such as S-band at 2.4 GHz, C-band at 4.97 GHz, 5.06 GHz, 5.18 GHz, 5.1 GHz, and 7.94 GHz, X-band at 10.73 GHz, 10.91 GHz, and 11.9 GHz, Ku-band at 13.52 GHz, 14.78 GHz, 14.97 GHz, 15.63 GHz, 16.4 GHz, 17.3 GHz, and 17.48 GHz, and K-band at 19 GHz. The manufactured reconfigurable patch antenna is proficient for several wireless technologies for instance industrial scientific medical band (ISM): Bluetooth, wireless-fidelity (Wi-Fi), ZigBee, internet of things (IoT), WiMAX, and smart power meters. Also, long term evolution (LTE), 5G applications, fixed wireless systems (FWS), and satellite communication applications.

A Wide Band Antenna for both S-Band and CBand Satellite Communication Applications

A Wide Band Antenna for both S-Band and CBand Satellite Communication Applications

Design and optimization of a deep learning algorithm assisted stub-loaded dual band four-port MIMO antenna for Sub-6 GHz 5G and X band satellite communication applications

In this article, C-type stubs loaded hexagonal shaped four-element MIMO antenna is proposed with improved isolation for sub-6 GHz 5G and X-band satellite wireless communication applications. Initially, the design and simulation studies of the MIMO antenna are performed using Computer Simulation Software (CST) software but its design parameter estimation and optimization consume higher time using conventional EM simulation tools. In order to solve this issue, Deep Learning algorithm-based approach has been proposed to determine the optimal physical parameters along with best possible performance characteristics. This suggested DL based approach is resource and time efficient for parameter estimation and optimization during the design process. To reduce design space and generation of an effective dataset, the feature reduction method (FRM) is implied during the design process. The S-parameters are predicted through Dual-Channel (DC-DNN) Deep Neural Network model. The dual-band MIMO antenna operates with −10 dB impedance Bandwidths of 40 % (2.8 GHz – 4.2 GHz), 38.41 % (6.1 GHz – 9.0 GHz) and shows excellent diversity performance. The proposed MIMO antenna is suitable for Sub-6 GHz n77 (3.3–4.2 GHz), n78 (3.3–3.8 GHz) 5G NR bands and also supports X band satellite (7.25–7.75 GHz and 7.9–8.4 GHz) communication applications.

A Ka-Band Silicon-Based Antenna-in-Package Design Using Characteristic Mode Analysis for Bandwidth Enhancement

With the emergence of 5G and satellite communication applications, where millimeter-wave (mm-wave) active phased arrays play an important role, the demand for a highly integrated and cost-effective method to achieve mm-wave antennas is an inevitable trend. Antenna-in-package (AiP) design is therefore becoming a hotspot. This paper presents the design procedure for a broadband silicon-based stacked patch antenna in Ka-band, which realizes a practical AiP structure for phased-array module integration requirements. A stacked-patch antenna on a high-resistivity silicon (HRSi) substrate is demonstrated to effectively extend the bandwidth with the guidance of characteristic mode analysis (CMA).The proposed antenna element and its 2 × 2 array were designed and fabricated using silicon bulk micromachining and wafer-level bonding technology. The measured results from the fabricated antenna prototypes showed that (1) the antenna element had an impedance bandwidth of 13.8% from 26.2 to 30.1 GHz, and the peak gain was 6.1 dBi at 28.9 GHz; (2) the 2 × 2 array realized an impedance bandwidth of 11.4% from 27.2 to 30.5 GHz, and the peak gain was 9.3 dBi at 28.5 GHz.

Global iridium market to reach $2 bn by 2028, driven by rising demand in satellite communication and IoT applications

Global iridium market to reach $2 bn by 2028, driven by rising demand in satellite communication and IoT applications

Design and Development of a Unique Antenna for Numerous Applications of Satellite Communication Based on Aluminium, Nickel and Copper Materials

Design and Development of a Unique Antenna for Numerous Applications of Satellite Communication Based on Aluminium, Nickel and Copper Materials

Wideband and Highly Selective BandPass Filter Using Substrate Integrated Waveguide Technology for Ku-Band Applications

A new compact design of bandpass filter using substrate integrated waveguide (SIW) is proposed and analyzed in this paper. It offers good in-band return loss, low insertion loss, wide passband, and high stopband attenuation. The filtering response is achieved by loading a couple of inverted tuning fork-shaped defected ground structures (DGS) on the bottom of the SIW cavity. DGS is utilized to enhance the upper stopband performance. To validate, the filter is fabricated using Rogers RT/Duroid 5880 with 0.508 mm thickness and tested. The filter has a center frequency of 15.44 GHz with 19% fractional bandwidth (FBW). The return loss is more than 20 dB and the insertion loss is about 1.2 dB. It finds its application in Ku band satellite communication.

Analysis and application research on key issues of channel coding

Channel coding plays a crucial role in enhancing the reliability and efficiency of communication systems, particularly when transmission channels are disrupted by noise and interference. This paper presents an in-depth review of various channel coding techniques, their applications, and future research directions. Key topics discussed include prevalent channel coding methods, such as repetition codes, convolutional codes, LDPC codes, turbo codes, and polar codes. The paper also delves into the selection of suitable channel coding parameters and their applications in digital TV, mobile and satellite communications, unmanned aerial vehicle data links, speech communication, and underwater acoustic channels. Moreover, the paper explores the performance analysis and comparison of different channel coding techniques, shedding light on their strengths and weaknesses. Lastly, the paper identifies emerging trends and challenges in channel coding research, providing valuable insights for researchers and practitioners in the field of communication systems. By examining these techniques and future directions, this comprehensive overview aims to contribute to the development of more robust and efficient channel coding schemes for a wide range of communication applications.

A Circularly Polarized Antenna for UHF Satellite Communication Applications

There is a tremendous demand for antennas with very broad bandwidth and gain so that one antenna can cover the entire frequency range of the satellite communication applications, which are rapidly expanding with the current technology for diverse platforms. Helical antennas are ideal for these applications due to their distinctive qualities such as circular polarization, wide bandwidth, excellent gain, and low-profile conformability. For transmitting and receiving applications, which comprise frequency ranges of 240MHz to 270MHz and 290MHz to 320MHz, respectively. A new design of circularly polarized double-wire helical antenna employing the butterfly approach has been created in this study. An antenna was designed, simulated, analyzed, and fabricated before being experimentally measured for important parameters such as axial ratio, gain, 3dB beamwidth, and voltage standing wave ratio.

ANN_ITU: Predicting rain attenuation with a hybrid model for earth-space links

Rain attenuation prediction of earth-space links is of vital significance for the application and development of satellite communication. Recently, most rain attenuation prediction methods are based on semi-empirical models or data-driven models, the former suffering from incompleteness problem, the latter faced with limited performance due to scarce data. In order to realize higher rain attenuation prediction performance, we propose a novel hybrid model ANN_ITU that combines advantages of the semi-empirical model and the artificial neural network. In ANN_ITU framework, the semi-empirical model ITU-R P.618-12 is leveraged to predict rain attenuation, and a six-layer artificial neural network is utilized to correct the rain attenuation predicted by ITU-R P.618-12, thus generating the final rain attenuation value. What’s more, we also present theories of two machine-learning based rain attenuation prediction methods, namely, random forest and support vector regression. Last but not least, we expound on processes of DBSG3 dataset filtering and data preprocessing. Experiments on DBSG3 dataset are carried out. Experimental results demonstrate that the hybrid ANN_ITU algorithm outperforms purely semi-empirical algorithms and data-driven algorithms. The evaluation indexes mean value, standard deviation, and root mean square value are 0.0355%, 19.63%, and 19.63%, respectively, which prove the effectiveness and precision of our rain attenuation prediction model ANN_ITU.