triple infinte summation loop

Hello ,

I am trying to write a code requiring a multi summation calculation from and to infinity (the equations is attached) . I have problem in coding this and not sure the way I have written that is correct and efficient.I simple substitute infinity to a number (e.g. 100 and 250) but not sure this is correct or not can please advise and check the code as well?

%%Calculating Z(k,n) to be used in the multi summation loop

z=zeros(100,4);
k=[1:100];

z1=2*hd*k+rwed;
z2=2*hd*(k+1)-rwed;
z3=2*hd*(k)+(2*zwd+rwed);
z4=2*hd*(k+1)-(2*zwd+rwed);

z=[z1;z2;z3;z4];
z=z';

%%Multi summation loop

P1=0;
for n=1:4
    for k=1:100
        for l=1:250 

              b1(n,k,l)=sqrt((2*l*yed)^2+z(k,n)^2);
              b2(n,k,l)=sqrt((2*ywd-2*l*yed)^2+z(k,n)^2);
              Arg_1=b1(n,k,l)*sqrt(s);
              Arg_2=b2(n,k,l)*sqrt(s);
              D=besselk(0,Arg_1)+besselk(0,Arg_2);
              P1=P1+D;
          end
      end
  end 

F1=P1*(kd*hd)/xed;

I would really appreciate your help in solving my problem.

Regards, Ehsan