OFDM Serializer

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Serializes complex modulations symbols from OFDM sub-carriers.

This is the inverse block to the OFDM Carrier Allocator. It outputs the complex data symbols as a tagged stream, discarding the pilot symbols.

If given, two different tags are parsed: The first key (Length Tag Key) specifies the number of OFDM symbols in the frame at the input. The second key (Packet Length Tag Key) specifies the number of complex symbols that are coded into this frame. If given, this second key is then used at the output, otherwise, Length Tag Key is used. If both are given, the packet length specifies the maximum number of output items, and the frame length specifies the exact number of consumed input items.

It is possible to correct a carrier offset in this function by passing another tag with said offset.

Input
Complex vectors of length
Output
Complex scalars, in the same order as specified in occupied_carriers.

Parameters

FFT length
FFT length
Occupied Carriers
See OFDM Carrier Allocator
Length Tag Key
The key of the tag identifying the length of the input frame in OFDM symbols.
Packet Length Tag Key
The key of the tag identifying the number of complex symbols in this packet.
Symbols skipped
If the first symbol is not allocated as in occupied_carriers[0], set this
Carrier Offset Key
When this block should correct a carrier offset, specify the tag key of the offset here (not necessary if following an OFDM Frame Equalizer)
Input is shifted
If the input has the DC carrier on index 0 (i.e. it is not FFT shifted), set this to false

Example Flowgraph

This flowgraph can be found at [1].

Rx ofdm fg.png

Source Files

C++ files
[2]
Header files
[3]
Public header files
[4]
Block definition
[5]