Fixed Service Receiver Research Articles

Numerical approximation of millimeter-wave frequency sharing between cellular systems and fixed service systems

This paper presents numerical analysis and simulation results in order to study the impact of interference between fixed service (FS) systems and 5G cellular networks at 28 GHz, 38 GHz, and 60 GHz millimeter-wave (mmWave) bands. For this study, two different scenarios were considered, i.e., the aggregation of interference from small cells into an FS receiver from (i) base stations (BSs) to their associated user equipment (UE) (downlink); (ii) from UEs to their associated BSs (uplink). The simulation results determined how much interference rejection is required to protect the operation of the FS. This study is essential when using mmWave technologies in cellular networks, to determine whether the newly deployed cellular systems can co-exist with pre-deployed FS systems or not. This paper presents closed-form numerical approximation results with Taylor series approximation along with intensive simulation results. Finally, this paper confirmed that the numerical approximation results were precise, i.e., that here were only marginal differences to the intensive simulation results.

Performance Limits of Cognitive-Uplink FSS and Terrestrial FS for Ka-Band

This paper investigates the performance limits of cognitive-uplink fixed satellite service (FSS) and terrestrial fixed service (FS) operating in the range 27.5–29.5 GHz for Ka-band. In light of standard recommendations from the International Telecommunications Union and a rain-fading channel model, we analyze the interference level at the FS receiver by considering statistical properties of the channel, propagation losses, and antenna patterns. By employing the interference constraint criterion at the FS, an analytical expression for the capacity of the cognitive-uplink FSS is derived, which is useful in understanding the limits in performance and the potential application of the considered coexistence scenario. Simulations are carried out to verify the theoretical derivations and highlight the impact of key parameters on the performance limits.

On the protection of fixed service receivers from the interference generated by non‐GSO satellite systems operating in the 3.7‐4.2 GHz band

SummaryIn this work, the current power‐flux density limits in Article 21 of the ITU‐R Radio Regulations for non‐geostationary satellite orbit (GSO) systems operating in the 3.7‐4.2 GHz band are analyzed. These limits aim the protection of fixed service receivers, operating in the same frequency band, from the interference produced by non‐GSO satellite systems. The analysis was motivated by Resolution 157 of the World Radiocommunication Conference 2015, that recognized the need for a revision of Article 21 with a view to enabling non‐GSO systems to operate in these fixed‐satellite service frequency bands while ensuring that existing primary services are protected. In the analysis, 5 different circular Walker Delta type satellite constellation structures, adequately chosen, are considered, and the results show that the current power‐flux density (pfd) limits may impose undue constraints to non‐GSO systems operating in this band. Therefore, a methodology to investigate a more adequate pfd limiting mask is presented and used to generate an alternative mask. An evaluation of the proposed pfd mask shows that it does not impose unnecessary constraints to the non‐GSO satellite systems. This, along with other facts, indicates that the proposed pfd limits are, indeed, much more adequate than the current ones.

Numerical Simulation Study for Frequency Sharing Between Micro-Cellular Systems and Fixed Service Systems in Millimeter-Wave Bands

This paper presents numerical simulation results to study the impact of the co-existence between a fixed service (FS) system and 5G small cell networks at 28-, 38-, and 60-GHz millimeter-wave (mmWave) frequency bands. For this paper, two scenarios are considered: aggregation of interference from small cells into an FS receiver from base stations (BSs) to their associated user equipment (UE) (downlink) and the aggregation of cellular interference at the FS receiver from UEs to their associated BSs (downlink). Moreover, mmWave-specific propagation characteristics and attenuation factors are considered for a more precise simulation study. The simulation results determine how much interference rejection is required to protect the operation of FS. In addition, currently available mmWave modular antenna array (MAA) architectures are introduced. Based on the information, additionalmmWave frequency sharing study is performed using the realistic MAA radiation patterns. Last, we compare and analyze the performance differences between ITU standard models and MAA solutions.

Protection of FS receivers from the interference produced by HEO FSS satellites in the 18 GHz band: Effect of the roll‐off characteristics of the HEO system satellite antenna beams

AbstractThis paper focuses on the protection of fixed service (FS) receivers from the aggregate interference produced by the satellites of multiple highly elliptical orbit satellite systems (HEOs). It analyzes the protection given to FS receivers operating in the 18 GHz frequency band by the power flux‐density (pfd) mask contained in Article 21 of the 2003 edition of the Radio Regulations [International Telecommunication Union, 2003.]. This mask establishes the maximum allowable value for the pfd produced by any of the satellites of a non‐geostationary system at the Earth's surface. The protection offered to FS receivers by this mask is analyzed in four interfering environments, each containing three identical HEO systems. Four types of HEO systems, with different orbital characteristics, are considered: three having satellites that operate only in the northern hemisphere and one having satellites that operate in both hemispheres. All satellite antennas are assumed to radiate 0.3° spot beams. Each HEO satellite is modelled so that the maximum pfd it produces at the Earth's surface just meets the RR Article 21 mask and the analysis takes into account the roll‐off characteristics of the satellite antenna beams. To reflect the multiplicity of possibilities concerning the geographical location and technical characteristics of the victim FS receiver (e.g. latitude, longitude, azimuth and elevation of its receiving antenna, antenna gain, receiver noise temperature, etc.) a number of cases were evaluated. The concept of interference in excess [Int. J. Satellite Commun. Networking 2006; 24: 73–95] was used to combine the results corresponding to FS receivers located at the same latitude and having the same receiving antenna elevation angle but for which the location longitude and the azimuth of the pointing direction of its receiving antenna are randomly chosen. Results are expressed in terms of the cumulative distribution function of the interference in excess. Copyright © 2008 John Wiley & Sons, Ltd.

On the power flux-density limits to protect the fixed service from HEO FSS satellites emissions in the 18 GHz band

This paper focuses on the protection of Fixed Service (FS) receivers from the aggregate interference produced by the satellites of multiple highly elliptical orbit satellite systems (HEOs). It analyzes the protection given to FS receivers operating in the 18 GHz frequency band by different power flux-density (pfd) masks. These masks establish the maximum allowable pfd produced by each HEO satellite at the Earth's surface. The protections offered by four different pfd masks are analysed in two interfering environments, each containing three HEO systems. Two types of HEO system, with different orbital characteristics, are considered: one having satellites that operate only in the northern hemisphere and another having satellites that operate in both hemispheres. To reflect the multiplicity of possibilities concerning the geographical location and technical characteristics of the victim FS receiver (e.g. latitude, longitude, azimuth and elevation of its receiving antenna, antenna gain, receiver noise temperature, etc.) a large amount of results and curves is usually generated by the studies, making it difficult to draw general conclusions on the protection offered by the pfd masks under analysis. In looking for alternative ways of presenting the obtained results, a new variable was defined: the interference in excess. This new variable was defined in a way so that its probability distribution function reflects the protection given to an FS receiver located at a given latitude with a given receiving antenna elevation angle. It indicates the protection of an FS receiver for which the location longitude and the azimuth of the pointing direction of its receiving antenna are randomly chosen. This allows the large amount of results to be compacted into a small number of more representative curves from which general conclusions on the protection offered by the different pfd masks are easily drawn. Copyright © 2006 John Wiley & Sons, Ltd.

Application of a new methodology for the coordination of the fixed service (FS) with mobile earth stations on board vessels in realistic interference conditions

This paper addresses an in-depth analysis of the interference produced to the fixed service (FS) by the earth stations on board vessels (ESVs) operating with geostationary satellites and proposes a new methodology for the development of coordination areas around the FS receivers, taking into account parameters such as the velocity of the ESVs and their frequency of passage from specific locations. Simulations performed in realistic interference conditions prove the validity of the new methodology, which can constitute the basis for the development of new methods for the coordination between the fixed service and the ESVs contributing, by this way, significantly to the harmonic coexistence of the two services.

A new methodology for the determination of the co-ordination area around stations of the fixed service (FS) with respect to mobile Earth stations on board vessels (ESVs)

The extensive use of Earth stations located on board sea going vessels (ESVs) has created the necessity for the development of a new type of co-ordination area around the fixed service receivers (FSRs) operating in frequency bands C and Ku. To date there is not a single method concerning the calculation of the co-ordination area around the FSRs, which takes into account the mobility of the interfering stations. This paper addresses an in-depth analysis of the interference produced to the FSRs by the ESVs and proposes a new method for the development of the co-ordination area around the FSRs, taking into account parameters such as the velocity of the ESVs and their frequencies of passage from specific locations. Simulations performed for three different operational scenarios prove the validity of the new methodology. Copyright © 2005 John Wiley & Sons, Ltd.

Protection of fixed service receivers from the interference produced by the non‐geostationary satellites in a fixed satellite service network: a statistical interference analysis

AbstractUntil 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 & Sons, Ltd.