MT Convolutional Interleaver (Standard)
- Updated2023-02-17
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MT Convolutional Interleaver (Standard)
Performs interleaving using a fixed number of branches and a fixed unit delay.
Each branch has different delays associated with it. Hence, the data input of each interleaver branch is delayed by a specific amount (the amount of delay in that branch) before the interleaver returns the data. A convolutional interleaver is twice as efficient as a block interleaver.
Inputs/Outputs
data in
The input data to the interleaver.
number of branches
The number of branches of the convolutional interleaver. Data elements pass through the branches in a cyclic fashion. For example, in an N branch convolutional interleaver, data element 0 goes through branch 0, element 1 goes through branch 1, element N-1 goes through branch N-1, element N returns through branch 0, and so on. Each branch incorporates different delays.
Default value: 0
unit delay
The unit delay value. If this value is defined as D, then the number of delays on the ith branch is (i×D). If the total number of branches is N, then i = 0, 1,…, N-1.
Default value: 0
initial state
The shift register values when the convolutional interleaver begins operation.
error in
Error conditions that occur before this node runs.
The node responds to this input according to standard error behavior.
Default value: No error
reset?
A Boolean that determines whether to check the current input parameters. The current input parameters are always checked on the first run of this node.
| TRUE | Checks input parameters. |
| FALSE | Does not check input parameters. |
Default value: TRUE
data out
The convolutional interleaved data returned by this node.
error out
Error information.
The node produces this output according to standard error behavior.
Examples of Convolutional Interleaving and Deinterleaving
The following example demonstrates convolutional interleaving and deinterleaving. Let the data in be: x0, x1, x2, x3, x4, x5, x6, x7, x8, x9, x10, x11, x12, x13, …
Interleaver Input
Interleaver Output
D = unit delay in the path.
Assume for this example that the unit delay = 1, and the initial state shift registers are initialized with values of 0 for both the interleaver and the deinterleaver.
Interleaved Data: x0, 0, 0, 0, x4, x1, 0, 0, x8, x5, x2, 0, x12, x9, …
Deinterleaver Input
Deinterleaver Output
Deinterleaved Data: 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, x0, x1, x2, x3, x4, x5, x6, x7, x8, x9, …