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ESA Document - Emits - ESA

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RECEIVER CHARACTERISTICS (X-BAND)<br />

Carrier acquisition threshold -153 dBm<br />

Carrier tracking Threshold -156 dBm<br />

Carrier Loop bandwidth (2BL in a C/N=10dB) 1000 Hz<br />

Noise Figure 1.6 dB<br />

Table 3-44: X-band transponder. Receiver characteristics<br />

RECEIVER CHARACTERISTICS (Ka-BAND)<br />

Carrier acquisition threshold -153 dBm<br />

Carrier tracking Threshold -156 dBm<br />

Carrier Loop bandwidth (2BL in a C/N=10dB) 100 Hz<br />

Noise Figure 1.6 dB<br />

Ranging Bandwidth (double sided) 3 MHz<br />

Table 3-45: Ka-band transponder. Receiver characteristics<br />

Figure 3-58: UHF TV-SHM link<br />

HMM<br />

Assessment Study<br />

Report: CDF-20(A)<br />

February 2004<br />

page 212 of 422<br />

The communications links are shown Figure 3-59 to Figure 3-62, under different modes<br />

(standard and contingency), distances and mission phases (cruise, surface operations, rendezvous<br />

and docking and orbiting around Mars). Three different bands are used: Ka-, X- and UHF-band.<br />

Additionally, a laser link is used.<br />

To calculate the data rates, the distance variation depending on the mission phase has been taken<br />

into account. The maximum distance Earth-TV during cruise to Mars is 0.92 AU. The maximum<br />

and minimum distances while the MEV is on the Martian surface are 1.37 and 1.1 AU<br />

respectively. During the whole mission, the maximum distance will be 2.7 AU and will happen<br />

during the solar superior conjunction.<br />

Data rates of laser and RF Ka-band links during the different SEM (Sun-Earth-Mars angle) of the<br />

superior solar conjunction are shown in Table 3-46.

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