Rationalfactor samplerate converter specification
D = fdesign.rsrc(L,M)
D = fdesign.rsrc(L,M,RESPONSE
)
D = fdesign.rsrc(L,M,CICRESPONSE
,D
)
D = fdesign.rsrc(L,M,RESPONSE
,SPEC
)
D = fdesign.rsrc(L,M,SPEC
,specvalue1,specvalue2,...)
D = fdesign.rsrc(...,Fs)
D = fdesign.rsrc(...,MAGUNITS)
D = fdesign.rsrc(L,M)
constructs
a rationalfactor samplerate filter specification object D
with
the InterpolationFactor
property equal to the positive
integer L
, the DecimationFactor
property
equal to the positive integer M
and the Response
property
set to 'Nyquist'
. The default values for the transition
width and stopband attenuation in the Nyquist design are 0.1π
radians/sample and 80 dB. If L
is unspecified, L
defaults
to 3. If M
is unspecified, M
defaults
to 2.
D = fdesign.rsrc(L,M,
constructs
an rationalfactor samplerate converter with the interpolation factor RESPONSE
)L
,
decimation factor M
, and the response you specify
in RESPONSE
.
D = fdesign.rsrc(L,M,
constructs
a CIC or CIC compensator rationalfactor samplerate convertor filter
specification object with the CICRESPONSE
,D
)'RESPONSE'
property
equal to 'CIC'
or 'CICCOMP'
. D
is
the differential delay. The differential delay, D
,
must precede any specification string.
Because you are designing multirate filters, the specification strings available are not the same as the specifications for designing singlerate filters. The interpolation and decimation factors are not included in the specification strings. Different filter responses support different specifications. The following table lists the supported response types and specification strings. The strings are not case sensitive.
Design String  Valid Specification Strings 

 See

 See

 See

 See


To
specify a CIC rationalfactor samplerate convertor, include the differential
delay after 
 See
To specify a CIC compensator rationalfactor
samplerate convertor, include the differential delay after 


'Gaussian' 
The specification string must be preceded
by an integervalued 
 See
If you use the quasilinear IIR design
method, 
 See

 See

 See

 See

 See

 See

D = fdesign.rsrc(L,M,
constructs
object RESPONSE
,SPEC
)D
and sets its Specification
property
to SPEC
. Entries in the SPEC
string
represent various filter response features, such as the filter order,
that govern the filter design. Valid entries for SPEC
depend
on the design type of the specifications object.
When you add the SPEC
input argument, you
must also add the RESPONSE
input argument.
D = fdesign.rsrc(L,M,
constructs
an object SPEC
,specvalue1,specvalue2,...)D
and sets its specifications at construction
time.
D = fdesign.rsrc(...,Fs)
provides
the sampling frequency of the signal to be filtered. Fs
must
be specified as a scalar trailing the other numerical values provided. Fs
is
assumed to be in Hz as are all other frequency values provided.
D = fdesign.rsrc(...,MAGUNITS)
specifies
the units for any magnitude specification you provide in the input
arguments. MAGUNITS
can be one of
'linear'
— specify the magnitude
in linear units.
'dB'
— specify the magnitude
in dB (decibels).
'squared'
— specify the
magnitude in power units.
When you omit the MAGUNITS
argument, fdesign
assumes
that all magnitudes are in decibels. Note that fdesign
stores
all magnitude specifications in decibels (converting to decibels when
necessary) regardless of how you specify the magnitudes.
Design a rationalfactor samplerate converter. Set the rational samplerate change to 5/3. Use the default Nyquist design with a transition width of 0.05π radians/sample and stopband attenuation of 40 dB. The Lth band factor in the Nyquist design is equal to the interpolation factor.
d = fdesign.rsrc(5,3,'nyquist',5,.05,40); hm = design(d,'kaiserwin'); %design with Kaiser window
Design a rationalfactor samplerate converter. Set the rational
samplerate change to 5/3. Use a Nyquist design with the 'N,TW'
specification
string. Set the order equal to 12 and the transition width to 0.1π
radians/sample. The Lth band factor in the Nyquist
design is equal to the interpolation factor.
d = fdesign.rsrc(5,3,'nyquist',5,'N,TW',12,0.1);
Design a rationalfactor samplerate converter. Assume the data
are sampled at 10 kHz. Set the rational samplerate change to 3/2.
Use a Nyquist design with the 'N,TW'
specification
string. Set the order equal to 12 and the transition width to 100
Hz. The Lth band factor in the Nyquist design
is equal to the interpolation factor.
d = fdesign.rsrc(3,2,'nyquist',3,'N,TW',12,100,1e4); hd = design(d,'equiripple');
design
 designmethods
 fdesign.arbmag
 fdesign.arbmagnphase
 fdesign.interpolator
 fdesign.rsrc
 setspecs