DSP Blockset

Step 3 -- Set the Lowpass Digital Filter Block Parameters.   Double-click one of the Digital Filter blocks and set its filter parameters as indicated in Figure ; this block is the lowpass filter that filters out the noise from the noisy sine wave signal.

Note that when implementing your lowpass filter (and any other filter) with the Digital Filter block, you need to provide the following basic information about your filter:

• Whether the filter transfer function is FIR with all zeros, IIR with all poles, or IIR with poles and zeros
• The desired filter structure
• The filter coefficients

Also note that you can provide the filter coefficients in several ways:

• Type in a variable name from the MATLAB workspace (such as lopassNum in Figure ). The variable could be a result of running filter design commands or of using the Digital Filter Design block to design a filter.
• Type in filter design commands from the Signal Processing Toolbox or the Filter Design Toolbox such as fir1(5, 0.2, 'low').
• Type in a vector of the filter coefficient values. If your vector of filter coefficients is large, rather than typing in the vector you can assign it to a variable in the MATLAB workspace and type in the variable name instead.

  

Lowpass Digital Filter Block Settings

Step 2 -- Get Necessary Blocks

Step 4 -- Set the Highpass Digital Filter Block Parameters