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Parameter | Requirements | Justification | |||
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Mechanical subsystem | |||||
Payload physical envelope | |||||
Payload mass | |||||
Camera aperture placement | Zenith panel Flush with panel? | ||||
Power subsystem | |||||
Payload energy consumption | 3 W for 3 minutes observation pr. pass | Estimation | |||
Downlink radio energy consumption | |||||
. Target observation time expected to be shorter than 3 minutes | |||||
Peak power needed | > 10 W | Should be able to operate TM/TC, downlink radio, ADCS and payload at once during target pass. | |||
Energy needed | Should be able to perform target observation (inkl. slewing maneuvering) and downlink for four consecutive passes | Peak power available | |||
Communications | |||||
Downlink data rate (usable bits) | 1 - 2 Mbit | Size Estimation of size of one data packettarget measurement packet, one pr. pass: 500 pixels x 500 pixels x 2 bytes/pixel x 10 channels = 5 Mbytes = 50 Mbits 10 kanaler er typisk det vi får med komprimering i spektralt domene basert på IDLEtechs / Harald Martens teknologi. | |||
Downlink frequency band | |||||
Downlink power/EIRP needed | Depending on GS antenna size, power available and freq. band | ||||
Downlink radio energy consumption | Ground station pass expected to be 8 < t < 12 min. One downlink pass pr. target observation | ||||
Ground station/data access | Depending on frequency band If possible, GS at NTNU, in addition to others | ||||
Launch and orbit | |||||
Orbit type | Polar (may or may not be SSO) | Target area is far north, ground stations expected to be far north | |||
Orbit height | 400 - 600 | Low orbit preferable due to better resolution | |||
Orbit inclination | |||||
Other parameters | Ω: 30 - 45 deg
| Pass should be close to mid-day over target area for best light conditions Should be limited to ensure satellite pass by target area day-time during summer/autumn time | |||
ADCS | |||||
Slewrate (max, precision) | 2 deg/s | In order to be able to point towards target during a pass | |||
Pointing accuracy | 0.1 deg | TBC | |||
Momentum budget | Satellite must be able to perform slewing manouver for four consecutive passes | ||||
Peak power needed during slew |