Multi-Rate FIR LMS Filter Functions

The functions described in this section perform the following tasks:

• initialize a multi-rate FIR LMS filter
• get and set the delay line values
• get and set the filter coefficients (taps) values
• set the adaptation step value
• perform filtering
• update the filter coefficients using the result of the filter operation
• free dynamic memory allocated for the functions state

To use the multi-rate FIR LMS adaptive filter functions, follow this general scheme:

1. Call ippsFIRLMSMRInitAlloc to initialize a multi-rate FIR LMS filter.
2. Call ippsFIRLMSMRPutVal a required number of times to place the input values in the delay line.
3. Call ippsFIRLMSMROne to filter the samples in the delay line.
4. Call ippsFIRLMSMRUpdateTaps to update the taps using the value of adaptation error that is based on comparison between filtered and reference signals.
5. Call ippsFIRLMSMRGetTaps and ippsFIRLMSMRSetTaps to get and set the filter coefficients (taps). Call ippsFIRLMSMRGetDlyLine and ippsFIRLMSMRSetDlyLine to get and set the values in the delay line.
6. Call ippsFIRLMSMRFree to release dynamic memory associated with the FIR LMS filter.

• FIRLMSMRInitAlloc
  Allocates memory and initializes an adaptive multi-rate FIR filter that uses the least mean squares (LMS) algorithm.
• FIRLMSMRFree
  Closes an adaptive multi-rate FIR filter that uses the least mean squares algorithm.
• FIRLMSMRSetMu
  Sets the adaptation step.
• FIRLMSMRUpdateTaps
  Updates the filter coefficients using the adaptation error value.
• FIRLMSMRGetTaps
  Retrieves tap values from the multi-rate FIR LMS filter.
• FIRLMSMRSetTaps
  Sets tap values in the multi-rate FIR LMS filter.
• FIRLMSMRGetTapsPointer
  Returns the pointer to the filter coefficients.
• FIRLMSMRGetDlyLine
  Retrieves the delay line contents from the multi-rate FIR LMS filter state.
• FIRLMSMRSetDlyLine
  Gets and sets the delay line contents of a multi-rate FIR LMS filter state.
• FIRLMSMRGetDlyVal
  Gets one delay line values from the specified position.
• FIRLMSMRPutVal
  Places the input value in the delay line.
• FIRLMSMROne
  Filters data placed in the delay line.
• FIRLMSMROneVal
  Filters one input value.

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