Requirements

In this rection requierements for the ᴾᵒCat spacecrafts (system) and corresponding mission are presented. These are to be defined by the team developing each mission and PocketQube.

Mission Requirements

Index Domain Description
M-0010 General The satellite will be launched in a LEO orbit corresponding to both its purpose and the international regulations.
M-0020 General The satellite must not contain entry resistant materials or completely detachable sections or appendages.
M-0030 General To comply with ESA's zero debris approach the satellite must reenter in less than 5 years.
M-0040 General The satellite must be able to control its attitude in case of payload acquisition requirements as well as high temperatures.
M-0100 Structural The satellite must abide to both its class' available standard, as well as the regulations imposed by the deployer entity.
M-0110 Structural The satellite must have all its deployable elements safely stowed during transport, storage and launch.
M-0120 Structural The satellite must be capable of of starting and using all its systems and appendices in a controlled manner.
M-0210 Electronic The satellite must keep its power source disconnected from all its subsystems during transport, storage and launch.
M-0220 Electronic The satellite must be capable of satisfactory harvesting all the necessary power during its entire lifespan.
M-0230 Electronic The satellite must regulate all its power and data lines, providing protection against potential electrical hazards.
M-0300 Computational The satellite must maintain complete control of its circuitry, data processes, communications, payloads and physical interfaces at all times.
M-0310 Computational The satellite must be able to store both the information obtained from payloads as well as telemetry: location, date, battery level, temperature, current and voltage in key nodes.
M-0400 Communications The satellite must be able to communicate and receive telecommands from both the ground station and other satellites.
M-0410 Communications The satellite must be able to maintain a satisfactory link budget and to allow control of the satellite by way of telecommands.
M-0420 Communications The satellite must be able to transmit and receive without an attitude requirement.

System Requirements

Owner Req ID Requirement Text Requirement Note
OBC OBC-0010 The OBC shall monitor all spacecraft subsystems.  
OBC OBC-0020 The OBC shall have an Scheduler which determines the execution of different tasks through time.  
OBC OBC-0030 The OBC shall provide and store the following housekeeping data: Satellite mode, Boot count, OBC error events, Internal satellite communication error events, RAM memory usage.​  
OBC OBC-0040 The OBC shall retrieve and store housekeeping data for all spacecraft subsystems​.  
OBC OBC-0050 The OBC shall monitor all satellite subsystems in order to verify their nominal behavior​.  
OBC OBC-0060 The OBC shall execute TC received from the GSeg.  
OBC OBC-0070 The OBC shall be able to control and command all subsystems via its interfaces​.  
OBC OBC-0080 The OBC shall retrieve and store scientific data from the Payload​.  
OBC OBC-0090 The OBC shall have data interfaces with all subsystems​.  
OBC OBC-0100 The OBC power supply voltage shall be 3.3 V. With 4% margin from datasheet
OBC OBC-0110 The OBC shall enable the manual transition between satellite modes if a TC from the ground is received​.  
OBC 0BC-0120 The OBC shall automatically transition between satellite modes based on battery levels.  
OBC OBC-0130 The OBC should allow in-orbit changes of its configuration.  
OBC OBC-0140 The OBC shall implement a command-less timer that triggers a recovery routine if a telecommand from the GS is not received after a certain period.  
OBC OBC-0150 The spacecraft should allow modifications to the OBC Software after the satellite assembly is complete and while on ground.  
OBC OBC-0160 The spacecraft shall have a timer, set to a minimum of 30 minutes, before operations or deployment of the antennas.  
OBC OBC-0170 No radio emission shall be allowed after the spacecraft has been integrated within the PocketQube deployer until 45 minutes after deployment.  
       
COMMS COMMS - 0000 The Communications Subsystem (COMMS) shall work in the ISM band via radio links. The Ground Station is set to 868 MHz (amateur). The S/C is able to receive and transmit in this band.
COMMS COMMS - 0010 The COMMS subsystem must transmit at a maximum power of 20 dBm. This power values takes into account the internal losses.
COMMS COMMS - 0020 The COMMS subsystem must support half-duplex communication, enabling both transmission and reception of data. The S/C can receive telecommands and transmit data via the RF link of the COMMS subsystem.
COMMS COMMS - 0030 Be able to deploy the omnidirectional quarter wavelength antenna once the satellite is deployed in space. The deployment will be conducted using a thermal knife.
COMMS COMMS - 0040 The COMMS shall periodically transmit the telemetry of the spacecraft The period of the beacon shall be configurable using telecommands and dependant of the battery state.
COMMS COMMS - 0050 All packets shall be tagged with a timestamp.  
COMMS COMMS - 0060 The COMMS must be able to receive Telecommands from the ground segment and send a reception acknowledgement. RF packets are received by the satellite. If they are correctly parsed and with the expected command counter, the S/C will transmit an acknowledgement.
COMMS COMMS - 0070 The COMMS shall have the capability to provide past telemetry housekeeping. Housekeeping data is present in the telemetry.
COMMS COMMS - 0080 The transmitted beacon shall contain a subset of information from the whole satellite housekeeping. Housekeeping data is present in the telemetry.
COMMS COMMS - 0090 OBC and COMMS subsystems must communicate through SPI.  
COMMS COMMS - 0100 The S/C shall be capable of changing the operating frequency using a telecommand.  
COMMS COMMS - 0110 The satellite must comply with european regulations.  
COMMS COMMS - 0120 Be able to distinguish between wanted packets and unwanted packets. This will be done making use of the packet ID.
       
EPS EPS - 0000 The EPS is capable of providing the requisite current for the other subsystems to function correctly. The current must not exceed 800mA
EPS EPS - 0010 The battery shall remain within safe temperature ranges.  
EPS EPS - 0020 The EPS shall provide an output of 3.3V ±5% at its output to power the other subsystems  
EPS EPS - 0030 The battery shall be able to charge via the umbilical port.  
EPS EPS - 0040 The satellite's battery shall be decoupled from the rest of the system during launch using mechanically controlled kill switches.  
EPS EPS - 0050 The EPS shall charge the battery automatically using the solar cells.  
EPS EPS - 0060 The EPS shall include protections to prevent battery damage  
EPS EPS - 0070 The MPPTs shall produce sufficient power to charge the battery  
       
ADCS ADCS - 0000 The communication between the chips of the ADCS and the OBC must be conducted via I2C.  
ADCS ADCS - 0010 The PQ must be able to detumble using the BDOT algorithm.  
ADCS ADCS - 0020 The satellite must be able to point the Payload at the nadir angle using the magnetic control law.  
ADCS ADCS - 0030 The ADCS must be able to estimate the satellite's position in an inertial reference frame.  
ADCS ADCS - 0040 The ADCS must be able to obtain the magnetic field in an inertial reference frame.  
ADCS ADCS - 0050 All sensors used in the ADCS must be calibrated and characterized by temperature.  
ADCS ADCS - 0060 The magnetorquers must be able to be fed with current.  
ADCS ADCS - 0070 The ADCS must use an active actuator.  
ADCS ADCS - 0080 The ADCS must have a fail-safe mechanism to enter a safe mode in case of anomalies.  
ADCS ADCS - 0090 The ADCS sensor's calibration parameters must be able to be modified via telecommand.  
P/L-1 PRFL - 0000 The payload shall have a sensitivity of -110 dBm  
P/L-1 PRFL - 0010 Frequency resolution has to be smaller or equal than 10 MHz  
P/L-1 PRFL - 0020 Output has to be an analogue voltage between 0 and 3.3 V  
P/L-1 PRFL - 0030 Maximum peak power consumption has to be smaller than 1.5 W  
P/L-1 PRFL - 0040 Average power consumption has to be smaller than 0.5 W  
P/L-1 PRFL - 0050 The L-band antenna has to be stowed inside the satellite  
P/L-1 PRFL - 0060 No debris in the payload antenna deployment  
P/L-1 PRFL - 0070 Non-operational temperature has to range from -40 to 80 ºC.  
P/L-1 PRFL - 0080 Operational temperature has to range from 0 to 45 ºC.  
P/L-1 PRFL - 0090 Antenna return losses must be lower than -6 dB in the L-Band  
P/L-2 RFI5G_010 The payload shall have a sensitivity of -110 dBm  
P/L-2 RFI5G_020 The payload frequency resolution must be smaller or equal than 10 MHz.  
P/L-2 RFI5G_030 The payload output must be an analogue voltage between 0 and 3.3 V.  
P/L-2 RFI5G_040 The payload's maximum peak power consumption must be smaller than 1.5 W.  
P/L-2 RFI5G_050 The payload's average power consumption must be smaller than 0.5 W.  
P/L-2 RFI5G_060 The payload must interface with the "IEEE Open PocketQube".  
P/L-2 RFI5G_070 The full PocketQube weight with the payload must be smaller than 250 g.  
P/L-2 RFI5G_080 The payload's non-operational temperature must range from -40 to 80 ºC.  
P/L-2 RFI5G_090 The payload's operational temperature must range from 0 to 45 ºC.  
GSeg GS - 010 At least one GS shall be available for bidirectional communication with the spacecraft.  
GSeg GS - 020 The GS shall comply with ITU requirements [RD5].  
GSeg GS - 030 The GS shall be able to receive signals from the PocketCube following an orbit consistent with the launch. Test may be performed by tracking another spacecraft operating in a similar orbit.
GSeg GS - 040 ​The GS shall be capable of receiving satellite messages.  
GSeg GS - 050 The GS shall be able to predict and schedule a satellite pass and store the prediction in an SQL-based database.  
GSeg GS - 060 The GS shall track the satellite during its passes over the station​.  
GSeg GS - 070 ​The GS shall provide mechanisms to control and manage the orientation of communication antennas.  
GSeg GS - 080 The GS shall be connected to the internet via a wired interface.  
GSeg GS - 090 The GS internet interface shall be accessible through a VPN.  
GSeg GS - 100 The GSeg shall retrieve the satellite data during its passes over the station, following an operations plan. ​  
GSeg GS - 110 ​The GSeg shall store the retrieved data (telemetry and scientific) from the satellite in the OpCen.  
GSeg GS - 120 The OpCen shall structure the retrieved data from the satellite in order to provide a simple and fast access.  
GSeg GS - 130 The OpCen shall send specific commands to the satellite, operator cannot create his own TC.  
GSeg GS - 140 ​The administration of the GS software can be done remotely.  
GSeg GS - 150 The GS shall forward the retrieved data to the OpCen.  
GSeg GS - 160 The GS shall be operable both locally and remotely, and both manually and automatically.  
GSeg GS - 170 ​The GS shall have antennas to operate at UHF band.  
GSeg GS - 180 The GSeg shall be composed of a minimum of one tracking, commanding and receiving station and an unique OpCen.​  
GSeg GS - 190 The GS shall be placed in a limited access area with controlled environment.  
OPS OPS - 010 ​The OpCen shall communicate with the GS using a VPN interface.  
OPS OPS - 020 ​The OpCen shall be connected with a wired network to internet.  
OPS OPS - 030 ​Only an administrator can modify OpCen configuration.  
OPS OPS - 040 ​The OpCen shall be placed in a limited access area.  
OPS OPS - 050 ​The OpCen shall provide a GUI interface to interact with the GS and the spacecraft.  
OPS OPS - 060 ​The OpCen GUI shall provide mechanisms to control an manage the GS remotely.  
OPS OPS - 070 ​The OpCen GUI shall provide mechanisms to operate the spacecraft.  
OPS OPS - 080 The OpCen GUI shall provide mechanisms to upload satellite configurations.  
OPS OPS - 090 ​The Opcen GUI shall provide a login mechanism before starting any activity.  
OPS OPS - 100 ​The OpCen shall exploit the retrieved data from the GSeg stations.  
OPS OPS - 110 ​The OpCen GUI shall list the different TC that can be sent to the spacecraft.  
OPS OPS - 120 ​The OpCen GUI shall present the download data from the spacecraft.  
OPS OPS - 130 ​The OpCen GUI shall plot stored data.  
OPS OPS - 140 ​The OpCen shall provide mechanisms to stop and resume spacecraft communications.  
OPS OPS - 150 The OpCen shall provide mechanisms to reboot the spacecraft.  
OPS OPS - 160 ​The OpCen shall provide mechanisms to perform a health check of the satellite.  
OPS OPS - 170 ​The OpCen shall provide mechanisms to request scientific and telemetry data from the satellite.  
OPS OPS - 180 ​The OpCen shall provide mechanisms to manually transit through satellite modes.  
OPS OPS - 190 ​The OpCen shall provide mechanisms to perform manual deployments on the satellite.