Difference between revisions of "Delay"

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== Example Flowgraph ==
== Example Flowgraph ==

Insert description of flowgraph here, then show a screenshot of the flowgraph and the output if there is an interesting GUI.  Currently we have no standard method of uploading the actual flowgraph to the wiki or git repo, unfortunately. The plan is to have an example flowgraph showing how the block might be used, for every block, and the flowgraphs will live in the git repo.
This flowgraph is taken from the [[Guided_Tutorial_PSK_Demodulation|QPSK Modulation / Demodulation]] tutorial. The Delay is used to match the transmit data to the receive data.

== Source Files ==
== Source Files ==

; C++ files
; C++ files
: [https://github.com/gnuradio/gnuradio/blob/master/gr-blocks/lib/delay_impl.cc]
: [https://github.com/gnuradio/gnuradio/blob/main/gr-blocks/lib/delay_impl.cc delay_impl.cc]

; Header files
; Header files
: [https://github.com/gnuradio/gnuradio/blob/master/gr-blocks/lib/delay_impl.h]
: [https://github.com/gnuradio/gnuradio/blob/main/gr-blocks/lib/delay_impl.h delay_impl.h]

; Public header files
; Public header files
: [https://github.com/gnuradio/gnuradio/blob/master/gr-blocks/include/gnuradio/blocks/delay.h]
: [https://github.com/gnuradio/gnuradio/blob/main/gr-blocks/include/gnuradio/blocks/delay.h delay.h]

; Block definition
; Block definition
: [https://github.com/gnuradio/gnuradio/blob/master/gr-blocks/grc/blocks_delay.block.yml]
: [https://github.com/gnuradio/gnuradio/blob/main/gr-blocks/grc/blocks_delay.block.yml blocks_delay.block.yml]

Latest revision as of 13:28, 26 January 2022

Delay the input by a certain number of samples. Positive delays insert zero items at the beginning of the stream. Negative delays discard items from the stream. You cannot initialize this block with a negative delay, however. That leads to a causality issue with the buffers when they are initialized. If you need to negatively delay one path, then put the positive delay on the other path instead.

Note that users have had issues when delaying by very large numbers.


(R): Run-time adjustable

Delay (R)
Number of samples/items to delay by

Example Flowgraph[edit]

This flowgraph is taken from the QPSK Modulation / Demodulation tutorial. The Delay is used to match the transmit data to the receive data.

Stage6 grc.png

Source Files[edit]

C++ files
Header files
Public header files
Block definition