Cost Benefit Analysis for "Non-Safety" Satellite Based Aeronautical Services

This paper examines the potential interference between the Mobile Satellite Service and the Fixed Service in the Ku band. At first, the mobile satellite stations operating at sea are presented and the aggregate and the single-entry interference criteria for the terrestrial fixed service stations are calculated. Then, all the parameters that influence the interference magnitude are presented and extensively analyzed. In order to evaluate the impact of each one of them in the interference calculations, different scenarios are taken into consideration and simulations are conducted in maritime and terrestrial environment. The results are thoroughly presented and analyzed. I. INTRODUCTION The increasing demand for Mobile Satellite Services the last decades has lead to the fast development of cost effective mobile VSAT terminals and their extensive use for many applications. Mobile VSAT antennae can easily be installed on almost every vehicle including cars, small vans, trucks, sea going vessels and mobile platforms like cruise ships, ferries, geo seismic ships, drilling vessels and oil production platforms. Many of these systems operate in the C band (6/4 GHz), while there is a great interest for their deployment in the Ku band (14/11/12 GHz) (uplink in 13.75-14.5 GHz and downlink in 10.7-12.75 GHz frequency bands) in geographic areas covered by these bands. These mobile satellite systems are used to provide wideband satellite services, such as streaming video, bringing Internet connectivity to remote areas and carrying sensitive voice or data traffic. The transmitting bit rates may vary between 19.2 kbps up to 1.544 Mbps (Ref 1). However, according to the International Telecommunication Union (ITU) Regulations, the 13.75-14.5 GHz and 10.7-12.75 GHz frequency bands are exclusive for the Fixed Satellite Service (FSS) in all ITU regions and allocated for use to the terrestrial Fixed Service (FS) in many countries around the world through ITU footnotes. Hence, whichever frequencies of operation for the mobile earth stations are chosen in the Ku band, there is a possibility of interference, either the earth station transmission interfering with reception at the Fixed Service stations (in the 13.75-14.5 GHz frequency band), or the Fixed Service station transmissions interfering with reception at the mobile earth stations (in the 10.7-12.75 GHz frequency band). The magnitude of interference between two systems operating in the same or adjacent frequency bands depends on many factors, such as the transmission loss along the interfering path and the permissible interference levels at the receivers. For the terrestrial Fixed Service, long- and short-term interference criteria have been established in order to facilitate the sharing with the other systems operating in the same frequency bands. The possibility and the magnitude of the interference need to be examined in detail in each case, taking all these factors that influence the interference into account. In case of a mobile earth station, significance must be given also to the time variant nature of the interference. That means that additional parameters should be taken into ) ( ) (

Deploying high throughput satellite systems in Ka band to accommodate the ever increasing demand for high data rates hits a spectrum barrier. Cognitive spectrum utilization of the allocated frequency bands to other services is a potential solution. Designing a cognitive zone around incumbent broadcasting satellite service (BSS) feeder links beyond which the cognitive fixed satellite service (FSS) terminals can freely utilize the same frequency band is considered in this paper. In addition, we show that there is a rain rate called rain wall, above which cognitive downlink communications become infeasible.

Communications-on-the-move (COTM) is becoming an indispensable feature for next generation satellites. Many commercial and government based satellite communications programs are including support for terminal mobility as a key feature. Adding COTM capabilities to regenerative (non-transponded) satellite systems, such as layer-2 and layer-3 switching satellites impacts the satellite system, network and protocol architecture and design. The unique challenges and complications arising from supporting COTM capabilities can impact all segments of a satellite communications program, including ground stations, satellites, and terminals. In this paper, we examine the key aspects associated with implementing mobile satellite services (MSS) for next generation regenerative satellites which were originally designed to support fixed satellite services (FSS). We identify common challenges that arise when architecting a mobile regenerative satellite communications system and show methods to successfully address them. In particular, we focus on the SPACEWAY satellite system and show how COTM can be supported through enhancement to the baseline architecture. SPACEWAY was originally designed to support commercial fixed satellite service. SPACEWAY implements the European Telecommunications Standards Institute (ETSI) Regenerative Satellite Mesh-A (RSM-A) air interface standard and complies with the ETSI Broadband Satellite Multimedia (BSM) Satellite Independent Service Access Point (SI-SAP). This will serve as a blueprint for standards based RSM-A systems and the concepts can be extended to other non-standards based regenerative satellite systems as well.

The Highly Elliptical Orbit (HEO), contrary to Geostationary Earth Orbit (GEO), is projected to cover landmasses of Northern Hemisphere and also the Polar Regions for both Fixed (FSS) and Mobile Satellite Service (MSS). The HEO configuration was chosen by the Soviet Russian Space Authorities for the Molnya and Tundra system in order to facilitate launching from their territory and ensure coverage throughout the entire former USSR territory. Examples of HEO systems are Molnya, Tundra, Loopus, Archimedes and Borealis of the El-lipso system. The Borealis configuration is a part of Ellipso hybrid satellite constellation, which has to be presented as a Hybrid Satellite Orbit (HSO). The HEO satellite constellation turned for 180 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">o</sup> will be able to cover territories of Southern Hemisphere including South Africa.

The INTELSAT ground network includes three Ku-Band Full Performance Antennas (KFPAs) at Beijing, China; Fucino, Italy; and Clarksburg, Maryland. However, these antennas are currently not capable of tracking satellites in geostationary transfer orbit. By upgrading the tracking capability of the three KFPAs, it will be possible to extend the launch support capability of the INTELSAT ground network to other frequency bands. In the Ku-Band, the extended transmit frequency range was specified and the Broadcast Satellite Service (BSS) transmit band was selected based on customer demand. This paper discusses the technical aspects of the antenna enhancements with an emphasis on the particular method used by Vertex Antenna Systems (division of Vertex Communications Corporation) in California, for monopulse tracking, the consequence of adding transmit BSS band capability, and a description of site-specific elements of the enhancements and testing. INTELSAT and Telespazio will jointly market the new launch and In-Orbit Test (IOT) services.

The 18.6–18.8 GHz band is utilized extensively for scientific uses. Passive microwave measurements in this frequency range are critical for weather forecasting and studies of climate and environmental impacts. This band, however, is shared with commercial communication systems that operate under the Fixed Satellite Service (FSS). FSS communication is used mostly for satellite TV broadcasting, and by a small number of Very Small Aperture Terminal (VSAT) systems. The Radio Regulations of the International Telecommunication Union (ITU) limit the level of FSS transmitted powers in order to avoid interference to passive sensors that operate under the Earth Exploration Satellite Service (EESS). However, Radio Frequency Interference (RFI) affecting spaceborne microwave radiometers such as WindSat, AMSR2 and GPM-GMI at 18 GHZ has been observed and documented for several years since 2010. Calculations considering sea surface reflection show that the observed RFI is consistent with or higher than what could be expected even from the limited level of transmitted power from the FSS. The IEEE Geoscience and Remote Sensing Society (GRSS) has brought this problem to the attention of the ITU Radiocommunication Sector (ITU-R) Study Groups, in view of impending decisions that could potentially dramatically increase the use of this band by commercial operators. The contributions by IEEE GRSS to ITU-R will be presented and various issues involved will be discussed.

Stimulated by industrial developments towards personal communications links via constellations of non-geostationary (NGSO) satellites, the Administrative Radio Conference of 1992 made allocations to the mobile-satellite service (MSS) in the range 1-3 GHz, but no specific provision for the feeder-links to and from such constellations was made at that time, other than to recognise that Radio Regulation (RR) No. 22 allows bands allocated to the fixed-satellite service (FSS) to be used for the feeder-links of other space services. The subsequent increase in the pace of development prompted the World Radiocommunication Conference of 1993 (WRC-93) to request the ITU-R to carry out interference studies in all FSS bands below 30 GHz, to provide a basis for WRC-95 to take appropriate decisions regarding the spectrum for the feeder-links. The ITU-R Study Group 4 therefore investigated the frequency sharing problems which would potentially occur if NGSO MSS feeder-links were implemented alternatively in the 4-7 GHz range, the 11-16 GHz range and the 18-30 GHz range. The paper outlines the scenarios studied, gives examples of the quantitative results obtained, indicates the principal conclusions and summarises the relevant outcomes from WRC-95.

Since 2016, when the Federal Communication Com-mission (FCC) initiated its first Processing Round for U.S. Market Access, more than twenty distinct entities applied for authority to launch and operate fixed satellite service (FSS) satellite constellations consisting of more than 70,000 satellites [1]. One of the fundamental challenges, from a technical, regulatory and financial perspective, of these systems is a low-cost, consumer broadband, user terminal solution that complies with today's strict regulations. At the national level, the FCC defines require-ments for satellite systems in its 47 CFR Part 25 Rules. The most pertinent of these regulations for user terminals are: power flux density (25.208), earth station gain mask requirements (25.209), offaxis equivalent isotropically radiated power (EIRP) density envelope requirements (25.218), and requirements for Earth stations in motion (ESIMs) (25.228). These regulations were first developed with geostationary (GSO) systems in mind, and have evolved to consider the increase in number of non-geostationary (NGSO) systems and megaconstellations. At the international level, the International Telecommunications Union (ITU) sets forth power flux density (PFD) and equivalent power density (EPFD) requirements in Article 22 of the Radio Regulations (RR). This work offers an overview of modern phased array user terminal technology (namely analog, digital and hybrid beamforming techniques), today's manufacturers of phased array technology, as well as the national and international regulations with which these devices must comply.

Until 1997, the power flux density (pfd) limits applicable to fixed satellite service (FSS) satellite transmitters to protect fixed service (FS) receivers operating in the same frequency band were those in Article 21 of the radio regulations. They were developed assuming that potentially interfering satellites in the FSS would only operate in the GSO. The need to revise these limits to allow for the protection of FS receivers from interference generated by non‐geostationary satellites has led to several studies, most of them based on the non‐realistic assumption that every visible satellite in a NGSO constellation produces the maximum allowed pfd level at the FS receive station location. To provide a quantitative indication of how pessimistic this assumption is, this paper considers a more realistic model in which the pfd entries reaching a given FS receiver location are characterized by statistically independent random variables. The probability density functions of these random variables depend on the operational characteristics of the NGSO network. The obtained results have also shown the need to consider some of the operational characteristics of NGSO satellite networks when evaluating the interference produced by their satellites. If these operational characteristics are not taken into account in the calculations, higher values of interference, that do not reflect the real interference environment, are obtained. Copyright © 2002 John Wiley &amp; Sons, Ltd.

In this paper, we consider the frequency sharing feasibility of Fixed Satellite Service (FSS) with Microwave Landing System (MLS) allocated in the C-band. On the basis of characteristics of MLS and FSS suggested by ITU and safety standards of MLS by ICAO, three interference scenarios are built and numerical simulations are carried out for investigating the frequency sharing between the two systems. From the simulation results, we calculate the separation distance between MLS and FSS ground antennas, required for frequency sharing by employing standard protection limits regulating the interference to noise ratio (I/N) of the receiver.

Interference analysis is crucial for the frequency sharing between satellite services according to the regulations and recommendations of International Telecommunications Union (ITU). For the fixed-satellite service (FSS) earth stations of our neighboring country in 8025–8400 MHz frequency band, the interference problems of FSS earth stations into earth exploration-satellite (EESS) service earth stations in specific link scenario are discussed via theoretical analysis and simulation calculation in this paper. The simulation results show that the interference of FSS earth stations into EESS earth stations currently registered at ITU meets the limit value of the recommendations, however the interference into the assumed EESS earth station cannot meet the limit value. The analyzed and simulated results can be references for the international coordination between the earth exploration satellite systems and communication satellite systems of neighboring countries in this band.

In this letter, we consider a cognitive radio network consisting of broadcast satellite service (BSS), high-density fixed-satellite service (HDFSS), and high-altitude platforms (HAPs) systems. The spectrum utilization within a satellite beam coverage is increased by deploying extra HAPs in the pre-determined hot-spot regions to existing cognitive systems in which the BSS and HDFSS share frequency bands. Since the multiple network nodes simultaneously employ the same frequency band, there exists a challenge to efficiently mitigate the interference between them. Therefore, we propose an iterative precoding and band allocation algorithm for multi-antenna HAPs to maximize the network data rate. In addition, we present other low-complexity techniques and compare them through simulation results.

The continuous transverse stub (CTS) technology incorporates the use of coaxial lines to produce effective microwave antenna structures that radiate an omnidirectional pattern with high efficiency and low return loss. In this paper a two-element coaxial CTS antenna array is designed to operate in the C-band with improved efficiency and gain. The proposed prototype of the C-band antenna, with design operating frequencies –5.18, 6.536 and 7.42 GHz, finds numerous applications in C-band satellite communications. During simulation, the efficiency at these frequencies had been observed to be 89.5, 87.6 and 95.9% and their corresponding gains were observed to be 7.54, 5.24 and 7.51 dB, respectively. The measured results of the C-band antenna prototype for the above stated frequencies were observed to be 5.185, 6.845 and 7.313 GHz, respectively. This antenna can be used in INSAT/super extended C-band, fixed-satellite services which include space to earth, earth to space as well as mobile satellite services. The radiation of the designed structure is omnidirectional in the horizon plane, with minimum return loss. These simple and low-cost coaxial CTS structures can be adopted in wireless communication systems.

LTE system will share the same frequency band with fixed-satellite service (FSS) in 3 400 ∼ 3 600MHz, which has been identified as one of the candidate bands for the future development of mobile systems. In this paper, deterministic analysis and Monte Carlo simulation are adopted to study the co-existence of two systems in 3 400∼3 600MHz based on the FSS parameters in China. In deterministic analysis, three types of interference, which are co-channel interference, adjacent channel interference and overdrive, are studied. Then interference probability of FSS earth station is simulated using Monte Carlo simulation, which is based on the result of deterministic analysis. The analysis result shows that LTE frequency offset from edge of FSS channel should be above 10MHz for downlink and above 5MHz for uplink in China.

Secondary use of the satellite spectrum by a terrestrial system is studied in this paper, focusing on broadcasting satellite services. Both spectrum sensing based access and database based access are discussed. Link budget analysis is used to define operational limits for spectrum sensing and transmission power control when the primary system is a digital video broadcasting – satellite services to handheld devices (DVB-SH) system. The results show that cognitive radio techniques should be applied with caution in satellite bands. The energy detection method does not support well spectrum sharing in the studied band. Rather the sensing should be based on the feature detection or matched filter detection. The results show that only short-range transmission can be used on a secondary basis in many environments when the secondary spectrum use is based on the sensing.