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Owning Palette: Adaptive Filters VIs

Installed With: Adaptive Filter Toolkit

Estimates the maximum step size for an adaptive filter that you create with the standard least mean squares (LMS) algorithm.

Details  Example

	x(n) specifies the input signal x(n) to the adaptive filter.
	filter length specifies the filter length of the adaptive filter. The value must be greater than or equal to 2. The default is 128.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	maximum step size returns the maximum step size that you can use to filter the input signal x(n).
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.

AFT Estimate Maximum Step Size for FIR LMS Details

This VI completes the following steps to estimate the maximum step size value for an adaptive filter.

1. Obtains a series of filter input vectors from the input signal.
2. Identifies the filter input vector that has the maximum signal power.
3. Calculates the reciprocal of the maximum signal power. The result is the maximum step size that you can use for the adaptive filter.

Example

Refer to the Estimate Maximum Step Size for LMS Adaptive Filter VI in the labview\examples\Adaptive Filters\Getting Started directory for an example of using the AFT Estimate Maximum Step Size for FIR LMS VI.