Satellite

 service providers com TIWS (http://www.internationalservices.telefonica.com/productos/nuestros-productos/satellite/). 


router de Iridium-WiFi (http://www.roadpost.com/Iridium-AxcessPoint-P817C334.aspx?UserID=151973477&SessionID=EcIU9dHk2FnK45pxQbkv#mailweb) que ens aniria molt bé, si no fos perquè transmet a 24 Kbps i té una cobertura de 30 m (no he trobat la potència transmesa ni si té una antena externa, és el que ens caldria saber per calcular la cobertura).

iDirect:

Here’s some text from our web site that describes the different players:

Equipment Vendors

Equipment vendors are generally distinguished between pure antenna manufacturers and satellite

equipment manufacturers that produce indoor or outdoor ground equipment including antennas, LNBs,

BUCs, hubs, routers, software and network management systems.

Satellite Operators

Satellite operators are responsible for the planning and cost of the construction and launch of satellite

into space. They own and manage a constellation of satellites and determine coverage and geographic

areas. Satellite operators lease this bandwidth to service providers, government entities, television

broadcasters, enterprises and sometimes direct to the end consumer.

Service Providers/ Network Operators

Service providers, sometimes known as network operators, are telecommunication companies or

specialized satellite service companies who sell a full service package to the end customer. They

lease capacity from satellite operators, purchase and operate the network equipment and the antenna,

and are responsible for the installation and maintenance of the network.

Customers

Customers are the enterprises, organizations and consumers who use satellite communication

services. Governments or large corporate customers may operate as their own service provider by

managing the equipment directly and leasing bandwidth from satellite operators. Individuals and

smaller enterprises typically work with service providers who manage the equipment and connections.

To be clear – iDirect is strictly an equipment vendor – we build the hardware and software in the hub system and remote routers (or modems if you prefer).  We also re-sell the other components needed to make a system like antennas, BUCs and LNBs although we don’t manufacture these ‘dumb’ items ourselves.  We don’t offer services…

A satellite network provider / operator will buy our gear, rent some ‘space segment’ from the likes of Intelsat, Hispasat etc. and deliver a service to end users – for example a bank or a mobile operator.  Sometime mobile operators are themselves satellite network operators for their own private network – this is because mobile backhaul networks are usually pretty large so justify buying a complete hub, and also for security reasons – mobile operators sometimes prefer to keep the backhaul in-house.

A satellite operator will typically just sell MHz of space segment on a particular transponder / satellite to a network provider.  The Network Operator will sell capacity in Mbit/s to the end user.

At the hub end (often located with the HQ or main switching site of an operator) they need some rack space for the hub and some servers (typically one 19inch rack is enough) and a large antenna (3m – 7m diameter, depending on a lot of parameters).  Sometimes you’ll find the mobile operator has this on their roof or in the car park.  Other times they rent capacity at a ‘Teleport’ where someone else has already invested in the antennas etc. and one can either just rent co-location space and install the hub there and connect to an existing antenna.  A final model is the VNO model  - Virtual Network Operator.  In this case someone (including the satellite operator themselves – Intelsat do this a lot) installs both hub antennas and iDirect hubs and in effect rents out slots in the hub so that a third party can run a network without all the capital expense. This is often done to provide start-up facilities to new operators or operators in new territories.  Later when they grow they might invest in their own hub.

High Throughput Satellite Opportunity

sobre satèl.lits

Estos son los tipos de satélites que nos interesan (high throughput satellites):
http://en.wikipedia.org/wiki/High_throughput_satellite
algunos son geostacionarios, con reuso frecuencial basado en muchos beams (como HYLAS, explotados por http://www.avantiplc.com/) y otros son de orbita baja (como O3B http://www.o3bnetworks.com/).

 un enllaç on es parla de com els satèlits es fan servir per donar enllaços de transport per a sistemes de cobertures mobil en entorns rurals:
http://webinars.telecoms.com/webinar/small-cells-and-satellite-making-rural-coverage-pay/

Cosas que nos interesan:
1. Deberíamos saber cual es el paper de empresas como iDirect en este negocio. Es un service provider, pero eso qué es? No tienen satélites propios sino que parece que dispongan de plataformas de explotación de los satélites. ¿Cuáles comercializan?
2. ¿Cuáles son los actores en el negocio de la explotación de los satélites?
3. He estado mirando en la pagina de Avanti (http://www.avantiplc.com/) y veo que tienen tres modos de contratación del ancho de banda de satélite: raw bandwidth, managed megabit y packaged customer accounts. Podrían ser útiles para optimizar el acceso al satélite. Como usarlos?
4. ¿Qué son las network management platforms?
5. Necesitaríamos algun tutorial (de Comm Mag?) sobre satélites de alto throughput (HTS), y entender el A-TDMA u otros sistemas de acceso.

Tutorial :Satellite based Comunicacions

Satellite based Internet. A tutorial

(.pdf)

Satellite based comunicacions

En general, tots els sistemes satelitals es poden classificar entre els de orbita geostacionaria, orbita mitja i orbita baixa (http://en.wikipedia.org/wiki/Communications_satellite), proporcionant mes taxa de bit, mes complexitat de receptors i menor tamany de les antenes respectivament. Miraré d'enviar-te un article (o un capítol de llibre) en el que apareguin els conceptes bàsics.

Ademés dels sistemes de conexió satelital que apareixen a la pagina de telecomsansfrontieres, caldria que tinguessim en compte també aquests altres dos:

http://www.iridium.com/default.aspx
http://www.o3bnetworks.com/telcos/mobile-backhaul

els dos pertanyen als tipus de sistemes de baixa òrbita.

T'adjunto també un enllaç on es parla de com els satèlits es fan servir per donar enllaços de transport per a sistemes de cobertures mobil en entorns rurals:
http://webinars.telecoms.com/webinar/small-cells-and-satellite-making-rural-coverage-pay/

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Possibles solucions:
Tactical communications
BGAN
VSAT
VHF-HF
KA-SAT
ISATPHONE

Enllaços:
http://www.tsfi.org/en/presentation/technology/51-moyens-techniques
http://www.academia.edu/2065737/Redes_Inalambricas_para_Zonas_Rurales


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Satellite based Internet. A tutorial

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