The feasibility of using a cube-sat with GPS location signal receivers communications payload from ground, air or sea targets (persons or objects) is proposed. Also we use encoded transmitted signals which are decoded after the signals are received by the cube-sat. I think encrypting tracking signals is needed so that even if such signals were intercepted, it will bear no meaning to the interceptor.
My proposal uses the 3U form factor.
My cube-sat GPS location tracker will help the SOF operators to tag, track and locate target persons or objects and make further strategic movements or decisions based on that information.
Platform accommodation requirements for the cube-sat GPS tracker will need at least 45 watts of power for the communications payload, GPS sensor, smartphone motherboard, and for the visible light high resolution camera.
Platform accommodation requirement for thermal control by containing most electronics like smartphone, communications payload inside a pressurized bag with multi-layered textile, just like an astronaut spacesuit. The cube-sat is set on a permanent spin so as to expose the surface equally during the time it is exposed to the sun and the spacesuit bag will protect when there is no sun exposure.
Platform accommodation requirement for data transfer rate less than 64 kbits/ sec. of data to be transferred to the ground if operating in a real-time data transfer mode.
Platform accommodation requirement for data transfer volume (per orbit) is less than 10 MB of data per orbit to be transferred to the ground if operating in a store-and-forward mode.
Platform accommodation requirements for bus stability is by using standards based satellite buses and attitude control is by using reaction wheels if need to correct the cube-sat attitude but will recommend a permanent spinning attitude with the visible-light camera pointed to the earth at all times to be able to take ground photos.
My concept can be implemented with current state-of-the-art flight-qualified components or COTS electronics so as to lower the cost of the cube-sat and are able to make the prototype on a shorter time frame of at least within 12 to 24 months.