Can i use real measurements as an group delay input in the fdesign.arbgrpdelay?How can i simulate,a filter through its group delay?

Dear all, I am trying to simulate a filter through its group delay response which. The Group delay data of the filter are given to me in the following form:

Freq(Hz)= 1.45E+09 ,1.45E+09...etc and the delays S21 Delay(s)=-2.02E-08,-1.32E-08...etc

From these have found until now the fdesign.arbgrpdelay seems the best solution for what I want to do.

I know that I have to normalize the frequency and I have already done it. By using the following code,and the first 10 elements of the group delay measurements that I have (the frequency is just an arbitrary selection for getting started).

f = [0 0.02 0.04 0.06 0.08 0.1 0.25 0.5 0.75 1];

w = [2 2 2 2 2 2 1 1 1 1];

hgd = fdesign.arbgrpdelay(N,f,g(1:10));

Hgd = design(hgd,'iirlpnorm','Weights','MaxPoleRadius',0.95);

fvtool(Hgd,'Analysis','grpdelay') ;

The following errors are returned:

Error using fdesign.abstracttype/superdesign (line 96) Design options must be specified as a structure or as parameter-value pairs.

Error in fdesign.abstracttype/design (line 11) varargout{1} = superdesign(this, varargin{:});

Error in allpassfilterarbitrarygrpdly (line 414) Hgd = design(hgd,'iirlpnorm','Weights','MaxPoleRadius',0.95); Could someone please help me?Or even suggest me an alternative?

Answer 1

[Honglei Chen]

It looks like you didn't specify the weights in your code after 'Weights' parameter, try

Hgd = design(hgd,'iirlpnorm','Weights',w,'MaxPoleRadius',0.95);