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Performs the direct sequence spread spectrum (DSSS) despreading operation on a spread sequence of data bits.

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sync search depth

The desired number of bits (not chips) over which to search for a sync confidence metric greater than the sync confidence threshold. This parameter is only applicable when reset? is set to TRUE.

Default: 0

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input chip stream

The sequence of data chips to despread.

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spreading code

The sequence of bits that determine how the bits in input bit stream are spread.

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sync confidence threshold

The minimum correlation required for which you can consider input chip stream to be synchronized with the spreading code. Configure this parameter only if you set reset? to be TRUE. Valid values are between 0.0 (no correlation required) to 1.0 (perfect correlation required), inclusive.

Default: 0

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error in

Error conditions that occur before this node runs. The node responds to this input according to standard error behavior.

Default: no error

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reset?

A Boolean that determines whether this node synchronizes despreading at each call using the sync search depth and sync confidence threshold parameters.

TRUE Synchronizes despreading at each call using the sync search depth and sync confidence threshold parameters.
FALSE Ignores the values of sync search depth and sync confidence threshold and continues despreading from the previous iteration.

Default: TRUE

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output bit stream

The despread series of bits returned by this node.

Note  

output bit stream has (1/L × input chip stream) number of elements, where L is the length of the spreading code sequence.

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sync found index

The synchronization index of the synchronization sequence found within the input chip stream. This parameter returns -1 if no sync is found.

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sync confidence metric

The measured confidence metric when input chip stream is aligned using the sync found index. Valid values are 0.0 (0% measured confidence) to 1.0 (100% measured confidence), inclusive.

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error out

Error information. The node produces this output according to standard error behavior.