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System design for Pan-European MSS services in S-band

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Abstract

This paper gives an overview of a suitable communications system capable of efficiently use the available S-band allocation for pan-European Mobile Satellite Services (15 MHz in both uplink and downlink for each of the two licensed operators) to provide different classes of services such as interactive mobile broadcast services enhancing DVB-SH offer, messaging services for handheld and vehicular terminals, realtime emergency services such as voice and file transfer, mainly addressing institutional users on-the-move such as fire brigades, civil protections, etc... The design is based on a modular, flexible and scalable system architecture enabling different channelizations and frequency allocations within each beam, allowing independent deployment of different service classes within different beams, whilst ensuring backward compatibility with DVB-SH legacy terminals.
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... More exhaustive insights of the E-SSA system architecture can be found in the standard [2] as well as in [3] and [4], which present overviews of the S-MIM specifications. ...
... Simulations have been carried out in the framework of the DENISE project [5] so as to assess the performance of the E- SSA radio interface in terms of aggregated throughput. [3] gives an overview of the overall DENISE system and provides first simulation results for this asynchronous access scheme. Considering a burst length of 1200 bits, the overall aggregate throughput can reach up to 5-6 Mbps for a bandwidth of 5 MHz for different E-SSA terminals EIRP (the typical configuration for E-SSA radio interface adopted in DENISE can be found in [3]). ...
... [3] gives an overview of the overall DENISE system and provides first simulation results for this asynchronous access scheme. Considering a burst length of 1200 bits, the overall aggregate throughput can reach up to 5-6 Mbps for a bandwidth of 5 MHz for different E-SSA terminals EIRP (the typical configuration for E-SSA radio interface adopted in DENISE can be found in [3]). Assuming that all the terminals transmit at the same data rate, namely 5 kbps or 10kbps, it corresponds respectively to 1200 or 600 parallel transmissions, considering one packet sent per user. ...
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... Additionally, a large number of receivers are distributed across space-air-ground-sea networks; these detect, acquire, and track radio waves to provide PNTRC services for various users, such as aircraft, vehicles, and vessels, etc. The service scenario diagram is shown in Figure 1, and the main systems are listed in Table 1 [32][33][34][35]. NavCom signals on LEOs, as a subset of the PNTRC source, also face many difficulties, including: ...
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... These services are also referred to as Service Segments (SS). In [50], three SS classes are defined, namely: ...
... The messaging communication service is asynchronous, one-to-one, and most often bursty. The asynchronous access is used for SS1 and SS2 [50]. Enhanced Spread Spectrum Aloha (E-SSA) is used for messaging services in the return link, first introduced by the European Space Agency (ESA). ...
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... Providing various services such as broadcast, messaging and bidirectional communications, this protocol relies on the Digital Video Broadcasting -Satellites services to Handhelds (DVB-SH, [2]) in the forward link and on two different interfaces in the return link: quasi-synchronous code division multiple access [3] that requires a synchronous access and Enhanced Spread Spectrum Aloha (E-SSA, [4][5][6]) that requires an asynchronous access. More exhaustive insights of the S-MIM protocol can be found in the standard [1] as well as in [7] and [8], which present overviews of the S-MIM specifications. ...
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... Let's consider a typical US urban environment with a 2 The spatial separation between samples after down-sampling was chosen to be 1 m in accordance with [4]. Figure 4 shows the p.d.f. of the measured signal envelope, whereas the dashed lines with markers give the results of curve fitting using the three p.d.f.s specified previously. ...
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Data
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... DENISE. The Demonstrator Emergency aNd Interactive S-band Services (DENISE) system [35], which is in the process of being standardized by ETSI under the name of S-Band Mobile Interactive Multimedia (S-MIM), describes an integrated satellite/terrestrial mobile system that provides interactive broadcast/multicast, data acquisition and two-way real-time services to subscribers. The S-band payload of a GEO satellite is assumed to provide communication links to users; however, non-GEO satellites are also compatible with this integrated system provided that Doppler pre-compensation countermeasures are put in place. ...
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