KiwiSat Communications Modules
1) Telemetry System:
We can't do anything with KiwiSat unless we know how well the spacecraft systems are performing. This is so essential that we need two systems to ensure that we always have telemetry.
KiwiSat will have two separate telemetry systems.
a) 400 bps PSK
b) 1200 bps AFSK packet
There are a number of alternatives e.g. CW, PSK31,
Parts required: Transmitter with PSK modulator, FM transmitter, Packet TNC
2) Forward Control System:
We need to be able to turn on and off the various systems on the spacecraft to ensure that the batteries remain healthy i.e. balance the power budget.
KiwiSat will have two separate Forward Control Systems.
a) DTMF decoder from an FM receiver
b) 1200 bps AFSK packet from an FM receiver
Parts required: FM receiver(s), DTMF decoder, Packet TNC
3) Science Data:
To make the science package data available to everyone we need a simple data transfer system.
KiwiSat will provide data in Packet Radio Format from a science package.
Either a) 1200 bps packet
or b) 9600 bps packet
Parts required: FM transmitter, Packet TNC, PACSAT file server system
4) Transponders:
KiwiSat will support the following transponders:
a) Mode U/V FM transponder (all components included above)
b) Mode U/V digipeater (all components included above)
c) Mode U/V Linear transponder (requires linear IF)
d) Mode L/V Linear transponder (requires L band receiver)
e) Mode L/V FM transponder (requires L band FM receiver)
5) Digitalker:
KiwiSat will carry a Digitalker for ID and publicity purposes.
Requires an additional digital voice module.
This is the current list in priority order. If we have a problem with weight, size, time etc some items may not be constructed.
Here are block diagrams of some of the modules :
