Search

    WEBMAIL    |    Intranet    |    Site Map

 

 

DESIGN AND ANALYSIS OF X-BAND TT&C AND K-BAND LOW GAIN ANTENNAS FOR FUTURE LEO MISSIONS - EXPRO PLUS

on 17 February 2015

ESA Open Invitation To Tender AO8205
Open Date: 13/02/2015
Closing Date: 11/03/2015

Status: ISSUED
Reference Nr.: 14.155.25
Prog. Ref.: EOEP-4 EO Prep. Acti
Budget Ref.: E/0092-E4 - EOEP-4 EO Prep. Acti
Special Prov.: B+DK+F+D+I+NL+E+S+CH+GB+IRL+A+N+FIN+POR+LUX+CZ+CDN+PL+RO
Tender Type: C
Price Range: 200-500 KEURO
Establishment: ESTEC
Directorate: Directorate of EO Programmes
Department: Science, Appl & Future Technologies Dept
Division: Future Missions Division
Contract Officer: Tchoualack, Cendrine
Last Update Date: 13/02/2015
Update Reason: Tender issue

The objective of the activity is the detailed design and analysis of: - Telemetry, Tracking & Command (TT&C) antennas with close to hemispherical pattern in X-Band. This is a transmit and receiver antenna - and Data Downlink (DDL) antennas with isoflux pattern in K-band for future Low Earth Orbit (LEO) missions. This is a transmit only antenna. The output of the activity will be antenna designs of sufficient detail to enable a direct follow-on of an EM development activity. During the activity antenna solutions with: - separate X-band TT&C and K-band DDL antennas - and also dual frequency designs, which enables the combination of the nadir TT&C and DDL functions, will be traded-off with regard to the antennas performance, satellite accommodation, manufacture, RF Interference,etc. The most promising solution will be taken forward to the detailed design phase of the activity. Background: At the moment all European Earth Observation LEO satellites use S-band and X-band almost exclusively for TT&C and DDL respectively. Consequently, these bands are becoming very congested. It is also expected that a sizable number of future EO missions will have a requirement to uplink large amounts of data for operation plans and dynamic spacecraft software modifications for which the coordination in S-Band will become increasingly difficult due to the limited bandwidth allocation in S-Band and the extensive use of this band. At the WRC-15, a new X-Band frequency allocation by the International Telecommunications Union (ITU) for the Earth Exploration Satellite Service (EESS), that include Low Earth Orbit satellites, for TT&C is planned for the range 7190-7250 MHz for the uplink. This new uplinkcan be used in combination with the existing EESS allocation in 8025-8400 MHz for the downlink. Regarding DDL, the current allocationin X-band is limited to 375 MHz, which also imposes serious limitations on the data rate. The ITU allocates four times more bandwidth in the 26 GHz K-band (i.e. 25.5 to 27 GHz) for EESS (space-to-ground) links . Also, current X-Band isoflux designs are quite large(around 500mm diameter), but X-band close to hemispherical pattern designs, and K-band isoflux designs can be done with smaller antennas that may make them more suitable for smaller missions.

If you wish to access the documents related to the Invitation to Tender, you have to log in to the ESA portal.