6.2.2 Deployment of Transmitter & Receiver from a GAS CAP (Option 2) A possible alternative to Option 1 involves the deployment of both the transmitter and receiver from a single GAS CAP. It would utilise a spin deployment system to eject the demonstrator. The initial spin axis would be along the minimum moment of inertia axis, meaning that after a period of time the demonstrator would transition to a “tumble.” At this point, and several hundred meters from the Shuttle, the micro wave transmitter (plus power supply) and rectenna (plus data relay system) would split and a tether system would be used to slowly increase the separtation the distance between the two. Data could be relayed to the Shuttle. Use of a tether would also enable a planar rectenna design for the same reasons identified for the ASAP demonstrator and its PIC rectenna. This option might also allow the use of lithium batteries because they do not have to be activated until some time after deployment and nor are they returned to Earth. Thermal problems are also minimised because of the greater radiating surface open to space. The major disadvantage of this option is that it would be very difficult to package a “meaningful” experiment within the 68 kg deployment mass available. (See related discussion in Section 5.1.1.) 6.2.3 Use of Hitchhiker G & M (Option 3) Hitchhiker G The HH-G offers the potential for larger and heavier experiment options. For example, a much larger transmitter and antenna could be located on a space-facing bracket attached to one of the standard mounting plates available (Figure 6.2-2). This would enable greater apertures for the transmitter, allowing the experiment to be conducted over a larger distance than any of the
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