Analog butterworth bandpass filter design problem

Hi, I am using following code to generate bandpass filter with bandwidth from 3GHz to 5GHz.

Can you please give me reason why i am getting spikes or noise for filter frequency response.

 clear;clc;
 fn1=50e9; % nyquist frequency
 wp=[3e9 5e9]/fn1;
 ws=[2.8e9 5.2e9]/fn1;
 Rp=1;
 Rs=80;
[N, Wn]=buttord(wp, ws, Rp, Rs, 's')
[B, A] = butter(N, Wn, 's');
bp_tf=tf(B,A);
figure(10)
wf=(0:1e-4:1);
h=freqs(B,A,wf);
fh=wf*fn1;
plot(fh,20*log10(abs(h)));
h=gca;
set(h,'XLim',[0 10e9],'YLim',[-100 10]);