Implementation

  In order to test our communication chain, we implemented a receiver to see if we could receive the temperature and print it on the screen. To do that, we started with the receiver that was implemented to receive the GPS signal in a former project (https://sourceforge.isae.fr/projects/project-cubesat/wiki/Receiver), since we are using the same waveform. In order to apply the receiver to our case, we had to remove the part that was linked to the RTTY system with the Baudot and ASCII Coding. Since we wanted an integer to indicate the temperature, that's what we implemented.

SubDemodTC.vi

We decided to use the same start sequence that the one of the GPS project and to use as well Manchester coding. Therefore, we only changed the last part about Baudot and ASCII coding.

Waiting for the start sequence
Figure 1: Waiting for start sequence

Conversion from Manchester to bits
Figure 2: Conversion from Manchester to bits

Conversion from bits to integer
Figure 3: Conversion from bits to integer

  To convert the bits to integers, we use the vi MT Pack bits.vi. This vi takes as an input a bit array, the number of bits per integer(7 in our case), and the type of integer(2 choices:signed or unsigned). We chose to work with signed integers according to the program on the development board. You can as well choose whether you are working with LSB (least significant bit first) or MSB (most significant bit first). In our case, we are working with MSB. At the output, it gives an array of integer which is as well the output of this vi.

Acquisition_v5TC.vi

Acquisition vi
Figure 4: Acquistion_v5TC.vi

 This vi is our main one, the one that we run while testing and where we are supposed to see the temperature. We put in an indicator the first element of the integer array at the output of the SubDemodTC.vi, since we are only sending one temperature, to see the value that was received.

Front panel of the Acquisition
Figure 5: Front panel Acquistion_v5TC.vi