Spanish Research Platform Ready For Service

September 2007
By Henry S. Kenyon

TERSO is the Spanish Ministry of Defense’s first software-defined radio (SDR) platform. It is a development system that will help the government create new waveforms and test new SDR equipment slated for use by the nation’s armed forces.
Research-oriented radio system opens door for future advanced tactical equipment.

An innovative software-defined radio soon will help the Spanish government test and develop new capabilities for its military communications systems. Researchers will be able to evaluate software and equipment quickly so systems can be modernized and the military can participate in multinational research programs.

Designed mainly for research, the Terminal Radio Software (TERSO) platform is the product of a joint program between the Spanish Ministry of Defense’s Directorate of Armaments and the Spanish information technology firm Indra Sistenas, Madrid. The main goal of the collaborative effort is to provide the Spanish government’s software-defined radio (SDR) laboratories with an open research and development system, explains Javier Herraez, Indra’s program manager for TERSO. “TERSO started as a technology demonstrator, but both Indra and the Ministry of Defense have decided to evolve TERSO to be the first Spanish SCA [software communications architecture] SDR platform,” he says.

As a development platform, TERSO will allow the Spanish government to conduct its own waveform-related research and to evaluate other systems’ waveforms. Herraez notes that the radio represents the first Spanish capability to test and evaluate SCA SDR equipment and waveforms.

TERSO is being implemented through a multiphased process. The first phase will be completed in December with the delivery of the platform to the Ministry of Defense. The version available in the first phase does not have any cryptographic functions, but it is fully compliant with the international software communications architecture (SCA).

TERSO has a single channel capable of supporting Ethernet to radio frequency (RF) transmissions. Herraez says that the unit contains all of the protocols, signal processing and RF capabilities necessary for SDR development. Radio frequency coverage ranges from 30 to 400 megahertz. The radio also operates on an instantaneous bandwidth that is selectable up to 1 megahertz in RF.

The radio’s intermediate frequency signal processing capabilities allow for 30-megahertz bandwidth processing. TERSO’s digital electronics can process up to 30 megahertz of instantaneous bandwidth without the need to modify the digital subsystem of the platform. This new processing power allows the system to support future waveforms.

The radio can operate in a frequency-hopping mode, and its internal electronics include a mixed architecture comprising a set of field-programmable gate arrays, digital signal processors and general purpose processors. TERSO also can transmit data at different rates, depending on modulation, data format and electronic countermeasure capabilities. But Herraez notes that data packet transmissions are not the radio’s major focus. “It’s more a lab-oriented tool in itself than a prototype for real radios,” he says.

As an SCA-capable platform, TERSO can be used to design and test waveforms for SCA compliance and to cross-check other platforms for compliance. As a part of the TERSO program, Indra is delivering a full set of waveform development and testing tools with the radio. Two sample test waveforms for Ministry of Defense use also will be included with the unit.

Although TERSO is a laboratory-based product, Herraez adds that Indra does have programs under way to develop SDRs for tactical ground and vehicular platforms.

Herraez expects TERSO to evolve to meet additional operational requirements. Noting that no additional specifications have yet been confirmed, he speculates that future system enhancements will probably include a multichannel capability and full red/black security separation.

Several TERSO units have been built, and Indra is in the process of integration and testing. Formal testing is scheduled for early fall with delivery of the complete sets at the end of the year. The finished product will include the radio platform, waveform development tools and test waveforms. The Spanish Ministry of Defense will use these TERSO sets to conduct SCA compliance and waveform portability testing on new SDR radios and to perform additional SCA research.

Indra’s work on TERSO is complemented by its ongoing participation in other SDR groups such as the Software Defined Radio Forum, the NATO Software Defined Radio Users Group and the European Defense Agency’s (EDA’s) SDR and Certification subgroup. Herraez notes that Indra is very active in SDR technology and international SDR cooperative programs.

Herraez shares that several joint European SDR programs have recently been launched that focus on joint interoperability. One of them is the Wireless Interoperability for Security (WINTSEC) study, which will explore solutions to wireless interoperability problems across Europe’s security agencies. The EDA also has begun a study focusing on SDR for military applications. Indra is participating in this effort in cooperation with several other European firms.

The ministries of defense for Finland, Sweden, Italy, France and Spain also announced a major EDA-managed SDR research and development program called the European Secured Software Defined Radio Referential (ESSOR). The goal of this project is to enhance the interoperability of medium-term national SDR programs and to promote a European technological and industrial capacity in SDR. Herraez believes that TERSO will probably play a major role in Spain’s participation in the ESSOR program. “The ESSOR program will be where all the major European technological capabilities in SDR will be shared in order to develop and disseminate European SDR capabilities,” he says.

Web Resources
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