European Space Agency

Building Blocks for Cost-Effective GSM over DVB-RCS

Objectives

The project has brought forward key enabling technologies for a new generation integrated satellite-cellular system targeting rural deployments. This includes a low cost, low power 1TRX GSM radio and bandwidth efficient GSM-over-IP-over-DVB/RCS integration for low opex GSM backhaul.

The project objectives were:

  • Development of low cost 1TRX radio for GSM BTS targeted for low capacity cells and with minimal power consumption allowing for all solar powered integrated satellite terminal/GSM BTS.
  • Minimal consumption of satellite bandwidth by efficient GSM over DVB-RCS implementation for calls using protocol compressions techniques.


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Challenges

The key issue was the development of elements that will bring capex and opex of the integrated VSAT/GSM BTS to the levels required to offer economically viable cellular services to presently uncovered areas.

Benefits

The building blocks developed in this project are important elements of STM’s new generation integrated satellite-cellular systems called Super PicoTM GSM Base Stations enabling satellite-based cellular backhaul at capex and opex figures far below existing solutions in the market.

Features

The radio module comprises a single mixed signal PCB in cast aluminium mechanical housing and interface to the GSM baseband modem over Ethernet.


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The transmitter is based on digital filtering and sampling rate up-conversion in an FPGA followed by Digital-to-Analogue conversion and direct up-conversion to 900 MHz. The maximum output power is 2W.

On the receive side the signal is down-converted to IF prior to Analogue-to-Digital conversion, sub-sampling, down-conversion to baseband, filtering and sampling rate down-conversion.

The optimised GSM-over-IP-over-DVB/RCS interface is implemented in terms of added functionality at both ends of the DVB-RCS satellite link, i.e. at the SatLink VSAT IDU and at the HUB. The enhancements include protocol header compression techniques The techniques reduces the satellite bandwidth consumption by more than 30% in most cases.

Plan

The following main activities have been successfully carried out:

  • Radio circuit board design, test and pilot production,
  • GSM-over-IP-over DVB-RCS system design and implementation of header compression techniques in SatLINK IDU and HUB.

The following reviews were held:

  • Baseline Design Review (October 2008),
  • Test Readiness Review (March 2009),
  • Final Review (April 2009).

Current status

The project is completed.

Status date

Friday, May 8, 2009 - 14:26