OFDM Transmitter: Difference between revisions

Revision as of 06:43, 18 February 2022

Hierarchical block for OFDM modulation.

The input is a byte stream (unsigned char) and the output is the complex modulated signal at baseband.

Cyclic Prefix Length: The maximum possible length of multi-paths in their time dispersion

Packet Length Tag Key: The name of the tag giving packet length at the input.

Occupied Carriers: A vector of vectors describing which OFDM carriers are occupied.

Pilot Carriers: A vector of vectors describing which OFDM carriers are occupied with pilot symbols.

Sync Word 1: The first sync preamble symbol. This has to be with zeros on alternating carriers (0., 1.536, 0., -1.536, 0., ...). Used for fine and coarse frequency offset and timing estimation. Length of sync sequence must be the same as the value of FFT length. To not use a sync word, None can be entered as this parameter's value.

Sync Word 2: The second sync preamble symbol. This has to be filled entirely. Also used for coarse frequency offset and channel estimation. Length of sync sequence must be the same as the value of FFT length. To not use a sync word, None can be entered as this parameter's value.

Header Modulation

Payload Modulation

Rolloff length (samples): The rolloff length in samples. Must be smaller than the CP.

Log Debug Info: Write output into log files (Warning: creates lots of data!)

@@ Line 25: / Line 25: @@
 ; Sync Word 1
-: The first sync preamble symbol. This has to be with zeros on alternating carriers (0., 1.536, 0., -1.536, 0., ...). Used for fine and coarse frequency offset and timing estimation. Length of sync sequence must be the same as the value of  FFT length.
+: The first sync preamble symbol. This has to be with zeros on alternating carriers (0., 1.536, 0., -1.536, 0., ...). Used for fine and coarse frequency offset and timing estimation. Length of sync sequence must be the same as the value of  FFT length. To not use a sync word, '''None''' can be entered as this parameter's value.
 ; Sync Word 2
-: The second sync preamble symbol. This has to be filled entirely. Also used for coarse frequency offset and channel estimation. Length of sync sequence must be the same as the value of  FFT length.
+: The second sync preamble symbol. This has to be filled entirely. Also used for coarse frequency offset and channel estimation. Length of sync sequence must be the same as the value of  FFT length. To not use a sync word, '''None''' can be entered as this parameter's value.
 ; Header Modulation