European Space Agency

IODA: Improvement Of Distress beacon Architecture


The objective of the project is to propose different axes to significantly lower the cost of COSPAS SARSAT beacons. Indeed, in addition to the focus on the oscillator cost reduction aspects, Technology Electronic Solutions proposes an original evolution to improve the complete beacon electronics.

To define new adaptations of COSPAS SARSAT medium term stability relaxation, we aim to investigate the possibilities in cost reduction on the current OCXO frequency sources, which provide this high frequency stability, creating a thermal isolation between the inner XTAL oscillator operation and outside temperature conditions.

The main focus will be on:

  • Process cost reduction,

  • New Package structure,

  • Save power consumption.
The final objective proposes a safe high quality product for all European Beacon Manufacturers at a price and consumption close to the structure of new generations of TCXO dedicated for COSPAS SARSAT applications.

Technology Electronic Solutions also has knowledge in electronic solutions for beacons thanks to its designed RF Modules for European Beacon manufacturers. It could propose, at this step, original evolutions to lower the cost of the complete beacon electronics.

The main areas will be:

  • Original electronic architecture,

  • Low cost power amplifier circuits,

  • High efficiency power supply circuit,

  • Low power micro controller for clever management of the radio transmitters and free memory space for customer applicative software.
The final objective is to propose to our customers (European Beacon Manufacturers) a low cost, low power and stand alone beacon module on a single board. The customer will only have to develop the external interfaces (antenna, man machine interface, battery pack), housing and appl


The proposed activities have been identified to provide Technology Electronic Solutions with market competitive products and market growth potential. The technical solutions consist of the development of low cost and low power OCXO structures and on low cost complete beacon electronics.


Through the switch off of the 121.5 MHz service, over 680 000 121.5 MHz beacon users will have to switch to 406 MHz beacons by February 2009. As 121.5 MHz beacons are much cheaper than 406 versions, a huge cost pressure will be placed on current beacon manufacturers to lower prices and find cost reduction solutions.

These events won't only have an effect on the electronic's beacon but also on the batteries which come in second position to the beacon's cost structure. Reducing the power consumption results in saving on the battery pack. As the major OCXO component provider for COSPAS SARSAT beacons today, it is strategic for Technology Electronic Solutions who must counter act to maintain or increase market share.

The proposed activities have been identified as the best solutions to provide Technology Electronic Solutions with market competitive products and market growth potential. The technical solutions consist of the development of low cost and low power OCXO structures and on low cost beacon complete electronics.
The current 406 MHz beacon market has approximately 50 000 beacons with a 5% yearly increase.
The 121.5 MHz beacon population is estimated to be 680 000 big with 30% being PLB and EPIRB in Australia and New Zealand and 30% being ELT for general and private aviation in northern America.

The proposed development would allow Technology Electronic Solutions to address two parallel markets. On one side, a low power, switch capable OCXO would allow to maintain or increase the market share at component level. The ability to provide a low cost electronics solution will provide new beacon manufacturers with a low cost solution and reduced time to market.


System Architecture and Building Blocks :

The intended development concerns only the transmitter module with a microcontroller and contains:

  1. An OCXO, that ensures the frequency stability of the signal requested by the COSPAS SARSAT system. The design and development are described in this proposal and will reduce the cost and power consumption of the transmitter module,

  2. A PLL (with two VCOs) that ensures the 121.5 MHz and 406 MHz generation from a single reference,

  3. A PHASE MODULATOR ensures the phase modulation requested by the COSPAS SARSAT system,

  4. A 406 MHz power amplifier stage ensures the 5W power emission. The new design approach will use a 10dBm 406MHz VCO from the PLL, a preamplifier and a discrete two stages power amplifier,

  5. A 121.5MHz power amplifier stage ensures the power level transmission required by the ETSI EN 300 066 European standard,

  6. A diplexer ensures the output on a single antenna port,

  7. A coupler ensures the detection of a short or open load on the antenna port,

  8. The micro-controller ensures the data message content, manages the timing requested by the COSPAS SARSAT system and the "homing" timing requested by the ETSI EN 300 066 European standard,

  9. Interfaces are provided so that the beacon manufacturers can easily integrate the beacon module into their housing.

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The Work Breakdown Structure of the IODA project is:

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WP1: OCXO process and manufacturing improvement:
WP1.1: Cost analysis and specification
WP1.2: Development

WP2: OCXO New package:
WP2.1: Specification and Technology choice:
WP2.2: OCXO design
WP2.3: OCXO fabrication and measurement

WP3: OCXO heather control:
WP3.1: Specification
WP3.2: OCXO Development and Optimisation

WP4: Transmitter with micro-controller :
WP4.1: Modules definition
WP4.2: Modukes Development and Optimisation
WP4.3: Transmitter RUN1
WP4.4: Transmitter RUN2

T0 took place on 14th Feb 2005. Baseline design review W22/05, 3rd of May 2005 for all the Work Packages (WP1.1,WP2.1,WP3.1,WP4.1)

MTR 1: FRW27/05, 8th of July 2005
WP1.2: Final Review
WP2.2: MidTerm Review
WP3.2: Final Review
WP4.2: MidTerm Review 1

MTR 2: W10/06, 7th of March 2006
WP2.3: Final Review
WP4.3: MidTerm Review 2

Final review: W30/06, 26th of July 2006
WP4.4: Final Review

Current status

The project is now completed.

Status date

Friday, March 7, 2008 - 17:29