# Assessing the Capacity and Coverage of Satellite IoT for Developing Countries Using a CubeSat
## 2 Mission Concept
### KITSUNE Mission  
The KITSUNE satellite has dimensions 340.5 mm \(\times\) 226.3 mm \(\times\) 100.0 mm and a weight of 7.544 kg, and the internal structure of the satellite is shown in Figure 4. KITSUNE was launched to ISS on 19 February and deployed on 24 2022. KITSUNE was developed as a dual satellite system; separating the components based on utilization of amateur and non-amateur frequencies. The amateur radio frequencies are selected for 2-unit main bus (2 UMB) and 3-unit camera payload, whereas 1-unit SPATIUM-II (space precision atomic-clock timing utility mission) hosts the total electron content (TEC) and SIoT payload while using non-amateur frequencies for communications.  
The 2 UMB controls the main payload of the Earth-observation mission to capture 5-m class images through amateur radio frequencies. It also provides direct power from its battery to SPATIUM-II, which has its own bus system. In addition, there is no control command from the 2 UMB to SPATIUM-II; therefore, they operate as a dual-satellite system housed in the same structure with a common battery. SPATIUM-II is controlled independently by a separate GS in Kyutech through non-amateur radio frequencies, and its SIoT mission is the described with space-segment and the GSTs in this paper.  
Figure 3: Implementation architecture of (**a**) SIoT for achieving full potential and (**b**) the proposed SIoT.  
SloT Mission  
The main aim of the SIoT mission can be described as a demonstration of a CubeSat-based SIoT system for achieving remote data collection and IoT service from GSTs in multiple countries. The mission objectives considering the satellite payload and the ground segment are listed below:  
* Development of SIoT payload using COTS components.
* Development of low-cost and lower power GSTs, which could be fixed or mobile stations that could collect a wide range of sensor data.
* Collaborative development of GSTs to employ the most suitable sensor configurations in developing countries and deploy GSTs in remote locations around the world.
* Remote data collection of sensor data using KITSUNE and distribution of data using an online database management system developed at Kyutech.
* Human capacity building, knowledge transfer and promotion of international collaboration in developing countries for satellite-based missions.  
In order to achieve the mission objectives, the technical mission requirements for the satellite payload segment were determined as:  
* The payload shall have multiple channels to receive data from various GSTs simultaneously.
* The SIoT receiver shall have sensitivity close to ideal sensitivity, the permissible sensitivity deviation should be less than 10 dB.
* The receivers shall be able to operate in two frequency bands (400 MHz and 433 MHz).
* The receiver modules shall be reconfigurable on-orbit in terms of spreading factor (SF), coding rate (CR), bandwidth (BW) and center frequency (CF).
* The payload shall be accommodated in a 1-unit CubeSat with current consumption of the receiver less than 250 mA to meet the available power budget of a 1-unit CubeSat.
* The payload shall be able to operate in the space environment.