labview - Frame content in transmitter / receiver

Question

I have some questions about frame construction in the example "Packet-based Digital Link" from here (and in the frame construction and it's aplication in general): https://decibel.ni.com/content/docs/DOC-18801

The pramaters of the transmitter and receiver frame look like this:

Now my questions are:

• What are guard bits? Are we receiving these bits at the receiver? What is their application? What are we using them for?
• How is PN order added to the synchronization bits? What is their application? How are they received at the receiver? What does the receiver do with them?
• What is packet number? Is it just a number from 1 to 46 when we send 46 packets?
• What are padding bits? Is it the beginning of a message repeated at the end of a frame? Are they ones alone, or zeros alone? For what purpose we transmit them and how do we receive them?
• What is blank frame? I assume it's used as an empty packet to ensure the connection is not lost, but I don't know if it is received by receiver.

Sadly I don't have any documentation describing the issues with this example and I'm not able to deduce why the programmer applied these things and how specifically they are captured. Could someone familiar with programming in Labview deduce something from the code?

Here is the code for transmitter:

Sub VIs (in links, for clarity of the post):

subGeneratePackets.vi

sub_calcpadding-symbolrate.vi

sub_generate_packet_array.vi

sub_PSKMod.vi

sub_padIQWF.vi

sub_Text_to_bitstream.vi

Here is the code for the receiver:

Sub VIs:

sub_NoiseEst_and_Chop_shell.vi

sub_resamp_and_demod_shell.vi

sub_resample_and_demodulate

sub_check_rx_packet_validity.vi (I think there may be something going on here with the verification of these packets transmitted from the transmitter)

sub_Reconstruct Data Message.vi

sub_Format Rx Data.vi

sub_Init_PSK_at_Rx.vi

If anyone is able to deduce something from the code I posted, I would be very grateful for help in answering these questions, because it would help me a lot in analyzing how the transmitter / receiver works. Thank you in advance!

question from:https://stackoverflow.com/questions/65895142/frame-content-in-transmitter-receiver

Answer 1

Waitting for answers