Documentation |
Package: comm
Apply pulse shaping by decimating signal using raised cosine filter
The Raised Cosine Receive Filter System object™ applies pulse-shaping by decimating an input signal using a raised cosine FIR filter.
To decimate the input signal:
Define and set up your raised cosine receive filter object. See Construction.
Call step to decimate the input signal according to the properties of comm.RaisedCosineReceiveFilter. The behavior of step is specific to each object in the toolbox.
H = comm.RaisedCosineReceiveFilter returns a raised cosine receive filter System object, H, which decimates the input signal. The filter uses an efficient polyphase FIR decimation structure and has unit energy.
H = comm.RaisedCosineReceiveFilter(PropertyName,PropertyValue, ...) returns a raised cosine receive filter object, H, with each specified property set to the specified value.
Shape |
Filter shape Specify the filter shape as one of Normal or Square root. The default is Square root. |
RolloffFactor |
Rolloff factor Specify the rolloff factor as a scalar between 0 and 1. The default is 0.2. |
FilterSpanInSymbols |
Filter span in symbols Specify the number of symbols the filter spans as an integer-valued positive scalar. The default is 10. Because the ideal raised cosine filter has an infinite impulse response, the object truncates the impulse response to the value you specify for this property. |
InputSamplesPerSymbol |
Input samples per symbol Specify the number of input samples that represent a symbol. The default is 8. This property accepts an integer-valued, positive double or single scalar value. The raised cosine filter has (FilterSpanInSymbols x InputSamplesPerSymbol + 1) taps. |
DecimationFactor |
Decimation factor Specify the factor by which the object reduces the sampling rate of the input signal. The default value is 8. This property accepts a positive integer scalar value between 1 and InputSamplesPerSymbol. The value must evenly divide into InputSamplesPerSymbol. The number of input rows must be a multiple of the decimation factor. If you set DecimationFactor to 1, then the object only applies filtering without downsampling. |
DecimationOffset |
Specify the number of filtered samples the System object discards before downsampling. The default is 0. This property accepts an integer valued scalar between 0 and DecimationFactor − 1. |
Gain |
Linear filter gain Specify the linear gain of the filter as a positive numeric scalar. The default is 1. The object designs a raised cosine filter that has unit energy, and then applies the linear gain to obtain final tap values. |
clone | Create RaisedCosineReceiveFilter object with same property values |
coeffs | Returns coefficients for filters |
isLocked | Locked status for input attributes and nontunable properties |
release | Allow property value and input characteristics changes |
reset | Reset internal states of System object |
step | Output decimated values of input signal |