Delay: Difference between revisions

From GNU Radio
Jump to navigation Jump to search
(add Example Flowgraph)
 
(One intermediate revision by one other user not shown)
Line 12: Line 12:
== Example Flowgraph ==
== Example Flowgraph ==


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.
This flowgraph is taken from the [[QPSK_Mod_and_Demod]] tutorial. The Delay is used to match the transmit data to the receive data.


[[File:Stage6_grc.png|800px]]
[[File:Qpsk_stage6_fg.png|800px]]


== 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 14:54, 9 December 2023

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.

Parameters

(R): Run-time adjustable

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

Example Flowgraph

This flowgraph is taken from the QPSK_Mod_and_Demod tutorial. The Delay is used to match the transmit data to the receive data.

Qpsk stage6 fg.png

Source Files

C++ files
delay_impl.cc
Header files
delay_impl.h
Public header files
delay.h
Block definition
blocks_delay.block.yml