Callisto | Consultancy: Digital Signal Process

Callisto has undertaken a number of consultancy support tasks for ESA involving Digital Signal Processing (DSP) and Ground Station Baseband Equipment. Following is a brief description of some of the projects we have supported:

Intermediate Frequency and Modem System (IFMS)

The Intermediate Frequency and Modem System (IFMS) is Telemetry, Telecommand and Ranging Modem using completely digital technology. It has been developed by ESA to meet the needs of Deep Space missions and will be deployed in all ESTRACK TT&C stations. The IFMS is being developed under contract by the BAE Systems Research Centre (UK). Callisto has provided support to ESA to monitor the activities of the IFMS contractor since June 2002.

The main tasks involved with this support are:

Review of technical documentation produced by the contractor.

Attending and preparing tests campaigns both at ESOC and BAE.

IFMS configuration and support for different ESA missions.

Ka Band Antenna Tracking Receiver Study

The objective of the study was to design and test a breadboard to validate a suitable architecture for a tracking receiver capable of operation in both near-earth and deep-space situations at frequencies up to Ka-Band. The breadboard design would then become a basis for a possible future receiver. This new device has been developed by BAE Systems Research Centre (UK) and has been integrated inside the IFMS mainframe. Callisto has provided support to ESA to monitor the activities of the IFMS contractor since June 2002.

The main tasks involved with this support are:

Responsible for technical aspects of the receiver.

Review of technical documentation produced by the contractor.

Attending and preparing tests campaigns both at ESOC and BAE.

Responsibility for the integration in Vilspa-4 ESTRACK antenna.

Telemetry Channel and Decoding System (TCDS)

The objective of the project is to design and develop a Telemetry Channel Decoding System as a replacement for the current decoder unit (CDS2A). This new device has been developed by BAE Systems Research Centre (UK) and has been integrated inside the IFMS mainframe. The replacement was flexible enough to accommodate a number of anticipated channel coding functions without redesigning the initial implementation.

The main tasks involved with this support are:

Review of technical documentation produced by the contractor.

Attending and preparing tests campaigns both at ESOC and BAE.

TCDS configuration and support for different ESA missions.

Responsibility for the integration of TCDS in Kiruna (1st station to be fitted).

Turbo Coder - Decoder Study

The objective of the study was to design and develop flexible hardware/software encoding/decoding algorithms to support the turbo code schemes specified in the CCSDS. During the second phase of the study, Space Engineering (Italy) has developed a breadboard containing a turbo encoder/decoder that has been integrated and tested in Vilspa-4 (Spain).

Callisto is providing consultancy support to ESA for this study with the following tasks:

Review of technical documentation produced by the contractor.

Attending and preparing tests campaigns both at ESOC and SE.

Responsibility for the integration of Turbo Decoder in Vilspa-4 (First station to be fitted).

GALILEO TTC Modem

The Galileo System is considered a strategic asset for Europe and the space-to-ground interfaces need to be protected against intentional and unintentional interference. For that reason the Galileo Programme decided on the need to develop on-board and ground equipment for the TTC services, which would use spread spectrum techniques to assure communication security. In addition to the normal TTC services (telemetry, telecommand, two-way ranging), there was an additional requirement for Integrity up-links and two-way time transfer, which had to use spread spectrum communications also. ESA launched a pre-development of the Galileo secure TT&C communication system in 2000. Under a consultancy contract to ESA, Callisto supported the definition and specification of the Ground Modem equipment for the Galileo Secure TTC system. The Callisto consultant played a lead role in the preparation of the equipment specifications, which were released under an ITT to European Industry in 2002.