MXPA06002783A - Systems and methods for inter-system sharing of satellite communications frequencies within a common footprint - Google Patents

Abstract

Two satellite communications systems can use the same frequency or frequencies in geographically overlapping footprints, without creating undue interference in a given system that is caused by the same frequency signal(s) that is/are used by the other system. In particular, an aggregate Effective Isotropic Radiated Power (EIRP) of the radioterminals and/or ancillary terrestrial components of a second satellite communications system in the common footprint is sufficiently low, and/or the receive antenna gain of a first satellite communications system is sufficiently low compared to the receive antenna gain of the second satellite communications system, so as to increase an aggregate receiver noise that is seen by the first satellite system receivers by an amount that does not substantially change a Quality of Service (QoS) of the first satellite communications system.

Description

SYSTEMS AND METHODS FOR SHARING BETWEEN SATELLITE COMMUNICATIONS FREQUENCY SYSTEMS WITHIN ONE COMMON BEAM AREA CROSS REFERENCE TO A RELATED APPLICATION This application claims the benefit of the provisional application No. 60 / 502,787, filed on September 11, 2003, entitled Systems and Methods for Inter-System Sharing of Satellite Communications Frequencies Within a Common Footprint, the disclosure of which is hereby incorporated by reference in its entirety as if fully set forth herein.

FIELD OF THE INVENTION This invention relates to radioterminal communication systems and methods, and more particularly to systems and methods of terrestrial and satellite radio-terrestrial communications.

BACKGROUND OF THE INVENTION Radioterminal satellite communications systems and methods are widely used for radiotelemal communications. Radioterminal satellite communication systems and methods they generally employ at least one space-based component, such as one or more satellites, which is configured for wireless communication with a plurality of satellite radioterminals. A satellite radio-communication system or method can use a single antenna beam that covers a total area handled by the system. Alternatively, in systems and communications methods of cellular satellite radioterminal, multiple beams are provided, each of which can handle different geographic areas throughout the service region, to collectively manage an entire satellite beam area. Thus, a cellular architecture similar to that used in conventional terrestrial cellular radio-terrestrial systems and methods can be implemented in systems and methods based on cellular satellites. The satellite typically communicates with radioterminals over a bi-directional communication path, with radio-terminal communication signals communicating from the satellite to the radio-terminal over a downlink or forward link, and from the radio-terminal to the satellite over an uplink or link. return. The total design and operation of cellular satellite radio-cellular systems and methods are well known to those skilled in the art and need not be further described herein. In addition, as used herein, the term "radioterminal" includes cellular and / or satellite radioterminals with or without a multi-line display; personal communication system (PCS) terminals that can combine a radioterminal with data processing, facsimile and / or data communications capabilities; personal digital assistants (PDA) that may include a radio frequency transceiver and a locator, Internet access Intranet, a Web browser, organizer, calendar and / or a global positioning system (GPS) receiver; and a conventional desktop computer and / or pocket-type computers or other devices, including a radio frequency transceiver. As used herein, the term "radioterminal" also includes any other device / equipment / source for emitting user that may have fixed geographic coordinates or varied time, and may be portable, transportable, installed in a vehicle (aeronautical, maritime , or terrestrial), or be located and / or configured to operate locally and / or in a distributed mode in any other location or locations on the earth and / or space. A "radioterminal" may also be referred to herein as a "radiotelephone", "terminal", "wireless user device". Terrestrial networks can improve the availability of the cellular satellite radioterminal system, the efficiency and / or economic viability through terrestrial reuse in at least some of the frequency bands that are distributed in cellular satellite radio-cellular systems. In particular, it is known that it can be difficult for cellular satellite radio systems to reliably service densely populated areas, since the satellite signal can be blocked by high structures and / or may not penetrate buildings. As a result, the satellite spectrum may be underused or not used in those areas. The terrestrial reuse of Satellite system frequencies can reduce or eliminate this potential problem. In addition, the total system capacity can be increased by introducing terrestrial frequency reuse of the satellite system frequencies, since the terrestrial frequency reuse can be much denser than that of the satellite system alone. In fact, capacity can be improved where it is needed most, that is, in densely populated urban / industrial / commercial areas. As a result, the entire system can become more economically viable, as it may be able to more effectively and reliably serve a larger subscriber base. The United States patent. No. 6,684,057 to Karabinis, entitled "Systems and Methods for Terrestrial Reuse of Cellular Satellite Frequency Spectrum", the disclosure of which is hereby incorporated by reference in its entirety as being fully disclosed herein, discloses that a satellite frequency may be reused in terrestrial fashion. by an auxiliary terrestrial network still within the same satellite cell, using interference cancellation techniques. In particular, a system according to some embodiments of the US patent. No. 6,684,057 includes a space-based component that is configured to receive wireless communications from a first radiotelephone in a satellite beam area over a satellite radiotelephone frequency band and an auxiliary terrestrial network that is configured to receive communications of a second radiotelephone in the satellite beam area over the satellite radiotelephone frequency band. The space-based component also receives the wireless communications from the second radiotelephone in the satellite beam area over the satellite radiotelephone frequency band as interference, together with the wireless communications that are received from the first radiotelephone in the satellite beam area over the frequency band of satellite radiotelephone. An interference reducer is responsible for the space-based component and the auxiliary terrestrial network that is configured to reduce interference from the wireless communications that are received by the space-based component of the first radiotelephone in the satellite beam area over the band. of satellite radiotelephone frequency, using the wireless communications that are received by the auxiliary terrestrial network of the second radiotelephone in the satellite beam area over the satellite radiotelephone frequency band. U.S. Patent Application Publication No. 2003/0054761 A1, published March 20, 2003, to Karabinis, entitled Spatial Guardbands for Terrestrial Reuse of Satellite Frequencies, the disclosure of which is hereby incorporated by reference in its entirety as if fully disclosed herein, discloses satellite radiotelephone systems that include a space-based component that is configured to provide wireless radiotelephone communications in a satellite beam area over a satellite radiotelephone frequency band. Area The satellite beam is divided into a plurality of satellite cells, where the satellite radiotelephone frequencies of the satellite radiotelephone frequency band are spatially reused. An auxiliary terrestrial network is configured to reuse in terrestrial form at least one of the frequencies of satellite radiotelephone that is used in a satellite cell in the satellite beam area, outside the cell and in some modalities separated from it by a band of space security. The space security band may be large enough to reduce or avoid interference between at least one of the satellite radiotelephone frequencies that is used in the satellite cell in the satellite beam area, and at least one of the satellite radiotelephone frequencies that is reused in terrestrial form outside the satellite cell and separated from it by the space security band. The space security band can be about half a radius of a satellite cell in width. Satellite radioterminal communication systems and methods that can employ terrestrial reuse of satellite frequencies are also described in the patent application of E.U.A. published Nos. US 2003/0054760 for Karabinis, entitled Systems and Methods for Terrestrial Reuse of Cellular Satellite Frequency Spectrum; US 2003/0054814 for Karabinis et al., Entitled Systems and Methods for Monitoring Terrestrially Reused Satellite Frequencies to Reduce Potential Interference; US 2003/0054762 for Karabinis, entitled Multi-Band / Multi-Mode Satellite Radiotelephone Communications Systems and Methods; US 2003/0153267 for Karabinis, entitled Wireless Communications Systems and Methods Using Satellite-Linked Remote Terminal Interiace Subsystems; US 2003/0224785 for Karabinis, entitled Systemas and Methods for Reducing Satellite Feeder Link Bandwidth / Carriers in Cellular Satellite Systems; US 2002/0041575 to Karabinis et al., Entitled Coordinated Satellite-Terrestrial Frequency Reuse; US 200/0090942 to Karabinis et al, entitled Integrated or Autonomous System and Method of Satellite-Terrestrial Frequency Reuse Using Signal Attenuation and / or Blockage, Dynamic Assignment of Frequencies and / or Hysteresis: US 2003/0068978 for Karabinis et al., Entitled Space-Based Network Architectures for Satellite Radiotelephone Systems; US 2003/0143949 for Karabinis, entitled Filters for Combined Radiotelephone / GPS Termináis; US 2003/0153308 for Karabinis, entitled Staggered Sectorization for Terrestrial Reuse of Satellite Frequencies; and US 2003/0054815 to Karabinis, entitled Methods and Systems for Modifying Satelllite Antenna Cell Patterns In Response to Terrestrial Reuse of Satellite Frequencies, the disclosures of which are hereby incorporated by reference in their entirety as fully set forth herein. Since satellite radio-terminal communication systems and methods are more widely used, the satellite radio-terminal spectrum can become more overloaded. As is well known to those skilled in the art, the downlink L-band satellite radio spectrum ranges from 1525-1559 MHz, and the uplink L-band satellite spectrum ranges from 1626.5-1660.5 MHz.

Inter-governmental and intra-governmental relations have distributed this frequency spectrum among multiple satellite radio-communication systems, including Inmarsat, Mobile Satellite Ventures (MSV), Mexico, Russia, Search and Rescue (SAR) and Radio-At-Sea (RAS). ). By distributing this spectrum, the two satellite communications systems are allowed to share a common frequency when covering geographically separated beam areas (sharing of inter-satellite frequency beam zones). It may be convenient for a satellite communication system to include large and multiple continuous bands of spectrum, for example up to 5 MHz or more continuous bands of spectrum, to allow, for example, the use of broadband technologies, such as band CDMA. wide (WCDMA). Unfortunately, the spectrum distributions of the present to each of the L-band systems mentioned above include many small frequency band slices, and may not include any, or may only include a small number of frequency bands, which are of 5 MHz or wider.

BRIEF DESCRIPTION OF THE INVENTION Some modalities of the present invention allow two satellite radioteleral communication systems to use the same frequency or frequencies in geographically overlapping beam regions, without creating undue interference in a given system (interference between systems) that is caused by the same signal or frequency signals that are used by another system. In some embodiments, a first satellite radioterminal communication system provides satellite radiotelephone communications to a first set of radioterminals on a first satellite radio-frequency band in a first beam area, as can be provided by a global beam and / or beams concentrated. A second radio-terminal satellite communication system provides radio-terminal communications to a second set of radioterminals that can also be responsible for auxiliary terrestrial components, on at least some frequencies of the first satellite radio-frequency band, in a second beam area which overlaps with the first beam area. The added effective isotropic radiated energy (EIRP) of the second set of auxiliary terrestrial and / or radioterminal components is sufficiently low, and / or the gain of the receiving antenna of the first satellite radio-terminal communications system is sufficiently low compared to the gain of the receiving antenna of the second satellite radio-terminal communication system, to increase the aggregate receiver noise observed through the first satellite system receivers by means of an amount that does not need to unduly impact the first satellite radio communication system, that is, it does not change substantially (including without change) the quality of service (QoS) of the first satellite radio communication system.

It has been found in accordance with some embodiments of the present invention, that the first gain of the satellite receiving antenna may be sufficiently low in relation to the second gain of satellite receiving antenna, and that the aggregate EIRP of the auxiliary terrestrial components and / or radioterminal can be sufficiently low, to increase the aggregate noise that is observed by the first satellite receiving antenna by means of an amount that does not need to unduly impact the QoS of the first satellite radioteleral communication system. Also, one or more radio-terminal satellite communication frequencies may be shared by a plurality of satellite radio-terminal communications systems over a geographically overlapping beam area without the need to impact the impact performance of any system properly. By allowing the sharing of satellite radio-terminal communication frequencies, relatively large continuous frequency bands can be assembled for the first and / or second satellite radiotelephone communication systems to allow, for example, the use of WCDMA technology, or any other wireless technology. broadband.

BRIEF DESCRIPTION OF THE DRAWINGS Figures 1 and 2 are schematic diagrams of satellite radioterminal systems and methods in accordance with the embodiments of the present invention.

DETAILED DESCRIPTION OF THE INVENTION Exemplary specific embodiments of the invention will now be described with reference to the accompanying drawings. This invention can, however, be modalized in many different forms and should not be construed as limiting the modalities set forth herein. Preferably, these embodiments are provided so that their description will be complete and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, similar numbers refer to similar elements. It will be understood that when an element is mentioned as "connected" or "coupled" to another element, it can be connected or coupled directly to the other element or intervention elements that are present. In addition, "connected" or "coupled" as used herein may include connected or wirelessly coupled. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used herein, the singular forms "a," "an," and "the" are intended to include plural forms as well, unless expressly stated otherwise. In addition it will be understood that the terms "includes", "comprises", "including" and / or "comprising", when used in this specification, specify the presence of characteristics, steps, operations, elements, and / or established components, but do not they exclude the presence or addition of one or more characteristics, steps, operations, elements, components, and / or groups thereof. Unless defined otherwise, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one skilled in the art to which the invention pertains. It will further be understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in a formal or idealized sense unless is expressly defined in the present. It should be understood that although the first and second terms are used in the present to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from the other element. Thus, the first element below can be named as a second element, and similarly a second element can be mentioned as a first element without departing from the teachings of the present invention. As used herein, the term "and / or" includes any and all combinations of one or more associated listed items. The symbol "is also used as a shorthand notation for" and / or "Figure 1 illustrates first and second satellite radio communication systems that are configured for sharing frequency of radiotelemal satellite communications within a common beam area in accordance with some embodiments of the present invention. Referring now to Figure 1, a first satellite radio-communication system includes a first satellite 100 that communicates on a first frequency band of satellite radio-terminal f-? (which may include one or more contiguous and / or discontinuous radioteleral satellite communication frequencies) over a first beam area 110 which may include a global beam and / or a concentrated beam (not shown). It will be understood that the first satellite radioteleral communication system may include first multiple satellites 100, which do not display for simplicity. The first satellite radio-communication system can be moralized, for example, in the well-known Inmarsat satellite radio communication system. Still with reference to Figure 1, a second satellite radio communication system includes a second satellite 200 that provides satellite radio-terminal communications with radio terminals 220 that can also be responsible and operative with auxiliary terrestrial components (ATC) 230 on the first band of satellite radiioterminal frequency fi in a second beam area 210, such as a concentrated beam area, which at least partially overlaps the first beam area 110, using a second satellite receiver antenna gain g2 that is greater than the first satellite receiver antenna gain gi of the first satellite radio-terminal system. In some modalities, approximately a gain difference of 20 dB is present. It will be understood that the second satellite radioterminal system may include more than one second satellite 200, and more than one concentrated beam, and may communicate with large numbers of radioterminals 220 and / or auxiliary terrestrial components 230. In addition, as used herein , the beam area 110 may be any beam area that is greater than the second beam area 210 and, in some embodiments, may extend over a hemisphere of the balloon. The second satellite radio-terminal communication system may be modalized, for example, in a satellite radio-terminal communications system that is provided by mobile satellite communication (MSV) companies, the assignee of the present invention, which is described, for example, in any or all of the US patent application publications and US patent 6,684,057 previously cited. Still with reference to Figure 1, the gain gi of the receiving antenna of the first satellite 100 may be sufficiently small relative to the gain g2 of the receiving antenna of the second satellite 200, so that the relatively low EIRP may be radiated by means of the radioterminals 220 and / or ATC 230 of the second satellite system. It has been found, in accordance with some embodiments of the present invention, that the relatively low EIRP of the radioterminals 220 and / or ATC 230, and the relatively low gain g-1 of the receiving antenna of the first satellite 100 may allow the same frequency band fi be used in geographically overlapping areas, such as the area of the second beam area 210, without unduly increasing an equivalent noise that is observed by the receiving antenna of the first satellite 100, i.e., without substantially changing (or changing at all) the QoS of the first satellite radioterminal system. Also, the low sensitivity of the overall beam and / or concentrated beam (s) of the first satellite 100 relative to the power level transmitted by the radioterminals 220 and / or ATC 230 can reduce the interference observed by the first satellite system. satellite radioterminal to an acceptable level. It will be understood by one skilled in the art that the above discussion has focused primarily on reducing uplink interference, from the radioterminals 220 and / or ATC 230, to the satellite 100. The uplink interference of the radioterminals of the first satellite system to the satellite receivers of the second satellite system can also be reduced, for example, by using systems or methods reducing interference , such as those described in the provisional patent application serial number 60 / 490,993 entitled Intra- and / or Inter-Sistem Interference Reducing Systems and Methods for Satellite Communications Systems for the inventor of the present Karabinis et al., filed on 30 July 2003 and U.S. Patent Application Serial No. 10 / 890,758 to Karabinis et al., entitled Intra- and / or Inter-System Interference Reducing Systems and Methods for Satellite Communications Systems, filed July 14, 2004, whose descriptions are incorporated herein by reference in their totality as fully established herein. Other interference reducing techniques can also be used. In addition, in the downlink, the interference can also be reduced based on the inherent discrimination of the concentrated beams and / or on the inherent discrimination that can be provided by the spatial separation between the first and second satellites 100 and 200. As an example specific, the + provides an impact analysis of a concentrated beam of the second satellite system in an uplink of a global beam of the first satellite system. In the example of Table 1, the first satellite system is the Inmarsat satellite system and the second satellite system is the MSV satellite system.

TABLE 1 As shown in Table 1, an increase in aggregate percentage noise of only 3.5% can occur in a receiver of a global Inmarsat beam due to system-wide satellite operations of MSV radio terminals 220. Table 2 provides an analysis on the impact of operational radioterminals with auxiliary terrestrial components 230 on a satellite receiver of the Inmarsat global beam. As shown in Table 2, an aggregate percentage noise increase of 3.25% may occur.

TABLE 2 As seen in the analyzes of the illustrative example presented in Tables 1 and 2, the aggregate aggregate effect of the satellite and auxiliary land operations of MSV in an uplink satellite receiver of a first global beam satellite 100 is: (? T /T)TOTAL=(?T/T)SAT+(?T/T)ATC=3.5+3.25=6.75% This amount can be very acceptable from an operational point of view, and does not need to impact or substantially impact QoS. From the point of view of downlink, the Inmarsat 110 satellite beam that can be impacted from a spectrum sharing with the MSV satellite system (second), can serve maritime users. As such, the second satellite system can be designed not to display the shared space on any or at least some of the satellite beams 210 that are formed on or near navigable channels. In some embodiments, a separation of at least two widths of a concentrated beam can be maintained between a navigable channel and the locations where the second satellite system 200 displays the shared aspect on its bundles of forward satellite points. This can produce significant discrimination (eg, 25 dB of concentrated beam discrimination) in relation to a first radioterminal of the maritime satellite system that can also use the shared frequencies. In addition, the auxiliary terrestrial components 230 can reuse the shared forward link spectrum sufficiently far from the navigable channels so that the aggregate effect of ATC on the receiver of a maritime radioterminal of the first system may be negligible (eg, less than the increase in added noise of 1%). A downlink analysis of the example, where the first system is an Inmarsat system and the second system is an MVS system is provided in table 3. As shown, there is an aggregate noise increase of 5%. Again, this Increase may be very acceptable from an operational point of view, and does not need to impact or substantially impact QoS of the first system.

TABLE 3 In the illustrative calculations presented above, in Tables 1 to 3, it is assumed that the second satellite system (MSV satellite system) uses a broadband code division multiple access waveform (W-CDMA) (width of 5 MHz carrier band) to communicate with radioterminals in their return service links, while using a broadband code division multiplexed waveform (W-CDM) (also of 5 MHz bearer bandwidth) to communicate with radioterminals in their front service links. However, any other type of waveform with features similar, or substantially similar, to the assumed W-CDMA / W-CDM waveform (at the EIRP level, carrier bandwidth, number of codes, and / or frequency reuse, etc.) may also be used without change, or substantially changing, the conclusions of Tables 1 to 3. The term "MET" as used in Tables 1 to 3, denotes a mobile terrestrial terminal and is used synonymously with the term "terminal" or "terminal"; the term "LHCP" denotes left circular polarization; the term "RHCP" denotes right circular polarization; and, as defined by row 7 of table 3; a MET of the first satellite system (Inmarsat system), such as MET 120 (see Figure 2) is assumed to receive information using a configured terminal of substantially RHCP (which is typically the case for MET Inmarsat), and therefore, the first satellite (Inmarsat satellite or satellite 100) transmits information in substantially RHCP, while the second satellite (satellite MSV or satellite 200) transmits information to MET 220 using substantially LHCP. Thus, an LHCP discrimination of 4 dB to RHCP is assumed in the calculation of Table 3 (row 7) reflecting an assumed coupling inequality between a forward link waveform of the second satellite and a MET antenna that is operational with the first satellite system. In addition, it is assumed that a MET of the second satellite system (MSV system) emits linearly polarized electromagnetic energy substantially, and it is assumed that a satellite of the first system is configured to receive substantially RHCP electromagnetic energy.

In addition, as used in Tables 1 to 3, the term EIRP denotes equivalent isotropic radiated power.

Figure 2 is a schematic diagram of satellite radio-terminal systems and methods in accordance with other embodiments of the present invention. As shown in Figure 2, systems and methods of frequency sharing of radio satellite communications in accordance with other embodiments of the present invention include a plurality of first radioterminals 120 communicating with a first satellite radio communication system including a first satellite 100 on a first frequency band of satellite radioterminal fi on a first effective isotropic radiated power aggregate EIRPi. A plurality of second radioterminals 220 communicate with a second satellite radio communication system including a second satellite 200 on the first satellite radio frequency band fi in a beam area 240 in a second effective radiated isotropic power aggregate EIRP2 that is less than the first effective added isotropic radiated power (EIRP2 <EIRP1). As described above in relation to Figure 1, the second aggregate effective isotropic radiated power may be sufficiently less than the first effective isotropic radiated power aggregate to increase the aggregate noise observed by the first satellite radio-terminal communication system by an amount that does not substantially change QoS of the first system of radio satellite communications. In some modalities, this increase may be less than 3.5%.

In other embodiments, as shown in Figure 2, the second radioterminal 220 also communicates in terrestrial manner with at least one auxiliary terrestrial component 230 on the first satellite radio-frequency frequency band f | in beam zone 240. In some embodiments of Figure 2, the second aggregate effective isotropic radiated power and an aggregate effective isotropic radiated power of at least one auxiliary terrestrial component 230 are sufficiently smaller than the first aggregate effective isotropic radiated power, to increase the noise that is observed by the first satellite radio communication system, for example, by the first satellite 100, by means of an amount that does not change substantially, and in some modalities, does not change, QoS of the first communication system of satellite radioterminal. In other embodiments, aggregate noise may increase by less than about 6.75%.

It is to be understood that the embodiments of Figure 1 and 2 may be combined in accordance with other embodiments of the present invention.

In addition, although the embodiments of the present invention have been described above primarily in relation to satellite radioteleral communication frequency sharing systems, they may methods of frequency sharing of analogue radioterminal should be provided.

Finally, it will also be understood that the relatively high antenna gain g2 of the second satellite 200 and the relatively high EIRP of the first radioterminals 120 can potentially create interference by the first radioterminal 120 to the second satellite radio communication system. This potential interference can be reduced or eliminated using interference cancellation techniques that are described in the US patent. 6,684,057 and / or publications of patent application of E.U.A. cited above, and / or using other interference reduction techniques.

In the drawings and specification, embodiments of the invention have been described and, although specific terms are used, they are used in a generic and descriptive sense only and not for the purpose of limiting the scope of the invention set forth in the following claims.

Claims (46)

NOVELTY OF THE INVENTION CLAIMS

1. - A satellite communication frequency sharing system comprising: a first satellite communication system that provides satellite communications on a first satellite frequency band in a first beam area by means of a first satellite; and a second satellite communication system that provides satellite communications with radioterminals over the first satellite frequency band in a second beam area that is a sub-area of the first beam area, by means of a second satellite, wherein a gain of receiving antenna of the second satellite is greater than a receiver antenna gain of the first satellite.

2. The satellite communication frequency sharing system according to claim 1, further characterized in that the aggregate effective isotropic radiated power of the radioterminals is sufficiently low to increase an aggregate noise that is observed by the first satellite communication system by an amount that does not substantially change the quality of service of the first satellite communications system.

3. The satellite communications frequency sharing system according to claim 1, further characterized in that an added effective isotropic radiated power of the radioterminals and a receiving antenna gain of the first satellite are sufficiently low to increase an aggregate noise that is observed by the first satellite communication system by an amount that does not substantially change a quality of service of the first system of satellite communications.

4. The satellite communication frequency sharing system according to claim 1, further characterized in that an added effective isotropic radiated power of the radioterminals and a receiving antenna gain of the first satellite are sufficiently low to increase an aggregate noise that is observe by the first satellite communication system for less than around 3.5%.

5. The satellite communication frequency sharing system according to claim 1, further characterized in that the second satellite communication system also provides terrestrial communications between the radioterminals and at least one auxiliary terrestrial component on the first satellite frequency band in the second beam area.

6. The satellite communication frequency sharing system according to claim 5, further characterized in that an added effective isotropic radiated power of the radioterminals and / or at least one auxiliary terrestrial component is sufficiently low to increase an aggregate noise that is observed by the first system of satellite communications for an amount that does not substantially change the quality of service of the first satellite communications system.

7. The satellite communication frequency sharing system according to claim 5, further characterized in that an added effective isotropic radiated power of the radioterminals and / or at least one auxiliary terrestrial component is sufficiently low to increase an aggregate noise that It is observed by the first satellite communication system for less than about 6.75%.

8. The satellite communication frequency sharing system according to claim 1, further characterized in that the second beam area is separated from navigable channels.

9. The satellite communication frequency sharing system according to claim 1, further characterized in that the second beam area is separated from the navigable channels by at least twice a width of the second beam area.

10. The satellite communication frequency sharing system according to claim 1, in combination with radioterminals.

11. The satellite communication frequency sharing system according to claim 5, in combination with at least one auxiliary terrestrial component.

12. The satellite communications frequency sharing system according to claim 1, characterized in addition because a receiving antenna gain of the second satellite is at least about 20 dB higher than a receiving antenna gain of the first satellite.

13. A satellite communication frequency sharing system comprising: a plurality of first radioterminals communicating with a first satellite communication system on a first satellite frequency band in a beam area in a first effective isotropic radiated power aggregate; and a plurality of second radioterminals communicating with a second satellite communication system on the first satellite frequency band in the beam region at a second aggregate effective isotropic radiated power that is less than the first aggregate effective isotropic radiated power.

14. The satellite communication frequency sharing system according to claim 13, further characterized in that the second added effective sotropic radiated power is sufficiently less than the first effective isotropic radiated power added to increase an aggregate noise observed by the first satellite communications system for an amount that does not substantially change the quality of service of the first satellite communications system.

15. The satellite communication frequency sharing system according to claim 13, further characterized in that the second effective isotropic radiated power aggregate is sufficiently less than the first effective added isotropic radiated power to increase an aggregate noise that is observed by the first satellite communications system for less than about 3.5%.

16. The satellite communication frequency sharing system according to claim 13, further characterized in that at least some of the second radioterminals also communicate in terrestrial manner with at least one auxiliary terrestrial component on the first frequency band satellite in the beam area.

17. The satellite communication frequency sharing system according to claim 16, further characterized in that the second aggregate effective isotropic radiated power and / or an added effective isotropic radiated power of at least one auxiliary terrestrial component and / or a added effective isotropic radiated power of at least some second radioterminals that also communicate in terrestrial form with at least one auxiliary terrestrial component is sufficiently less than the first effective isotropic radiated power added to increase aggregate noise observed by the first system of satellite communications for an amount that does not substantially change the quality of service of the first satellite communications system.

18. The satellite communications frequency sharing system according to claim 16, characterized in that the second aggregate effective sotropic radiated power and / or an added effective isotropic radiated power of at least one auxiliary terrestrial component and / or an added effective isotropic radiated power of at least some second radioterminals that also communicate in terrestrial with at least one auxiliary terrestrial component and sufficiently less than the first effective isotropic radiated power added to increase an aggregate noise that is observed by the first satellite radioterminal communications system for less than about 6.75%.

19. The satellite communication frequency sharing system according to claim 13, further characterized in that a beam area of the second satellite communication system in a beam area of the first satellite communication system is separated from the navigable channels.

20. The satellite communication frequency sharing system according to claim 13, further characterized in that a beam area of the second satellite communication system in a beam area of the first satellite communication system is separated from the navigable channels by means of at least twice a width of a beam area of the second satellite communication system.

21. - The satellite communication frequency sharing system according to claim 16, in combination with at least one auxiliary terrestrial component.

22.- The method of frequency sharing of satellite communications for a first satellite communications system that provides satellite communications on a first satellite frequency band in a first beam area by means of a first satellite, the method comprises: communication between radioterminals and a second satellite communication system on the first satellite frequency band in a second beam area that is a sub-area of the first beam area by means of a second satellite, wherein a receiver antenna gain of the second satellite is higher than a receiver antenna gain of the first satellite.

23. The satellite communication frequency sharing method according to claim 22, further characterized in that an added effective isotropic radiated power of the radioterminals is sufficiently low to increase an aggregate noise that is observed by the first satellite communication system per an amount that does not substantially change a quality of service of the first satellite communications system.

24. The satellite communication frequency sharing method according to claim 22, further characterized in that an effective isotropic radiated power aggregated from the radioterminals and a receiver antenna gain of the first satellite are sufficiently low to increase an aggregate noise that is observed by the first satellite communications system by an amount that does not substantially change a quality of service of the first satellite communications system.

25. The satellite communication frequency sharing method according to claim 22, further characterized in that an added effective isotropic radiated power of the radioterminals and a receiving antenna gain of the first satellite are sufficiently low to increase an aggregate noise that is observe for the first satellite communications system for less than about 3.5%.

26. The satellite communication frequency sharing method according to claim 22, further characterized in that it comprises: terrestrial communication between at least some radioteleminals and at least one auxiliary terrestrial component on the first satellite frequency band in the second zone of beam.

27. The satellite communication frequency sharing method according to claim 26, further characterized in that an added effective isotropic radiated power of the radioterminals and / or at least one auxiliary terrestrial component is sufficiently low to increase an aggregate noise that is observed by the first satellite communications system for an amount that does not change substantially a service quality of the first satellite communications system.

28. The satellite communication frequency sharing method according to claim 26, further characterized in that an added effective isotropic radiated power of the radioterminals and / or at least one auxiliary terrestrial component is sufficiently low to increase an aggregate noise that it is observed by the first satellite communication system for less than about 6.75%.

29. The satellite communication frequency sharing method according to claim 22, further characterized in that the second beam area is separated from the navigable channels.

30. The method of sharing satellite communications frequency according to claim 22, further characterized in that the second beam area is separated from the navigable limes by at least twice a width of the second beam area.

31. The satellite communication frequency sharing method according to claim 22, further characterized in that a receiving antenna gain of the second satellite is at least about 20 dB and higher than a receiving antenna gain of the first satellite.

32.- The method of frequency sharing of satellite communications for a plurality of first radioterminals that communicate with a first satellite communication system on a first satellite frequency band in a beam area in a first aggregate effective isotropic radiated power, the method comprises: communication between a plurality of second radioterminals and a second satellite communication system on the first band of satellite frequency in the beam area in a second added effective isotropic radiated power that is less than the first effective added isotropic radiated power.

33. The satellite communication frequency sharing method according to claim 32, further characterized in that the second added effective isotropic radiated power is sufficiently smaller than the first effective isotropic radiated power to increase an aggregate noise observed by the first satellite communications system for an amount that does not substantially change the quality of service of the first satellite communications system.

34. The satellite communication frequency sharing method according to claim 32, further characterized in that the second added effective sotropic radiated power is sufficiently less than the first effective added sotropic radiated power to increase an aggregate noise observed for the first satellite communications system for less than around 3.5%.

The method of sharing satellite communications frequency according to claim 32, characterized in that it comprises: terrestrial communication between at least some of the second radioterminals and at least one auxiliary terrestrial component on the first satellite frequency band in the beam area.

The satellite communication frequency sharing method according to claim 35, characterized in that the second aggregate effective isotropic radiated power and / or an added effective isotropic radiated power of at least one auxiliary terrestrial component is sufficiently smaller than the first added effective isotropic radiated power to increase aggregate noise that is observed by the first satellite communications system by an amount that does not substantially change a quality of service of the first satellite communications system.

37. The satellite communication frequency sharing method according to claim 35, further characterized in that the second added effective isotropic radiated power and / or an added effective isotropic radiated power of at least one auxiliary terrestrial component is sufficiently less than the first effective isotropic radiated power added to increase aggregate noise that is observed by the first satellite communications system for less than about 6.75%.

38.- The satellite communication frequency sharing method according to claim 32, further characterized in that a beam area of the second satellite that is a subset of the beam area is separated from the navigable channels.

39. - The satellite communication frequency sharing method according to claim 32, further characterized in that a beam area of the second satellite that is a subset of the beam area is separated from the navigable channels by at least twice a width of a beam area of the second satellite.

40. Satelltal communication frequency sharing system according to claim 3, further characterized in that at least one radio-terminal of the set of radioteleminals of the second satellite communication system communicates with the second satellite when emitting linearly polarized electromagnetic power in substantial form.

41.- The satellite communication frequency sharing system according to claim 5, further characterized in that at least one radio-terminal of the set of radioteleminals communicates with at least one auxiliary terrestrial component by emitting substantially linearly polarized electromagnetic power .

42. The satellite communication frequency sharing system according to claim 40, further characterized in that a receiving antenna of the first satellite is configured to receive substantially circularly polarized electromagnetic power.

43. - The satellite communication frequency sharing system according to claim 13, further characterized in that at least one of the plurality of second radioterminals communicate by emitting electromagnetic power linearly by substantially polarized and where the first satellite comprises a receiving antenna that is configured to receive substantially circularly polarized electromagnetic power.

44.- The satellite communication frequency sharing system according to claim 13, further characterized in that the first satellite comprises an antenna that is configured to emit right circularly polarized electromagnetic power substantially and where the second satellite comprises an antenna which is configured to emit left circularly polarized electromagnetic power substantially.

45. The satellite communication frequency sharing method according to claim 22, further characterized in that the first satellite comprises an antenna that is configured to emit right circularly polarized electromagnetic power substantially and wherein the second satellite comprises an antenna which is configured to emit left circularly polarized electromagnetic power substantially. 46.- The satellite communications frequency sharing system according to claim 22, further characterized in that at least one of the radioterminals is communicated by emitting substantially linearly polarized electromagnetic power and wherein the first satellite comprises a receiving antenna which is configured to receive substantially circularly polarized electromagnetic power.