mobmovescale.m

基于OFDM的无线宽带系统仿真It contains mainly two parts, i.e. link-level simulator and system-level simulator.

function [xym,xyv] = mobmoveScale(xym,xyv,amean,vmean,dt,rombvec,centerBsLoc,desireBsLoc,dmin)
% DESCRIPTION [xym,xyv] = mobmove(xym,xyv,amean,vmean,dt,rombvec)
%  Move and initiate position of users.
% INPUT
%  xym --     Complex position of users possibly. NaN for users that have not yet
%             received any position and thus are regarded as new.
%  xyv --     Complex speed [m/s].
%  amean --   Average acceleration of mobiles.
%  vmean --   Mean speed of mobiles.
%  dt --      Time interval since last call to this routine.
%  rombvec -- Two complex vectors determining the area within which
%             mobiles are folded.
% centerBsLoc --
%             location which should be the base station for investigation,
%             users will move in an area under this cell, this is mainly
%             for SFN investigations. Keep nan to investigate multi cell
% rot --      Rotation of user area, use complex values with abs(rot)=1,
%
% OUTPUT
%  xym --     New position.
%  xyv --     New speed.
% TRY
%  plot(mobmove(zeros(1000,1),zeros(1000,1),1,10,1,[1 i]*1000),'.')
%  plot(mobmove(zeros(1000,1),zeros(1000,1),1,10,1,[1 i]*1),'.')
%  plot(mobmove(nans(1000,1),zeros(1000,1),1,10,1,[1+i i]*1000),'.')
% SEE ALSO
%  mrequest, terminate

% by Magnus Almgren 000505

% Move users.
raa = exp(-mdiv(dt.*amean,vmean));
% raa is the correlation between the new and the old xyv
% and does not impact the variance.
xyv = xyv.*raa+sqrt(1-raa.^2).*vmean/sqrt(pi/2).*irandn(size(xyv));
xym = xym + xyv.*dt;

% Give new mobiles speed and position.
newones = isnan(xym);

% Generate position and wrap into simulated area.
xym(newones)= 0;
dist_new_ones = abs(xym - desireBsLoc);
newones2 = or(dist_new_ones<dmin,newones);

if isnan(centerBsLoc)==1
    centerBsLoc=-mean(rombvec);
end

if exist('rombvec','var')
    if all(isfinite(rombvec))
        while ~isempty(newones2)
            xym(newones2) = rand(size(xyv(newones2),1),2)*rombvec(:);
            xym = (wrapinto(xym+centerBsLoc,rombvec,'romb')-centerBsLoc);
            dist = abs(xym - desireBsLoc);
            newones2 = find(dist<dmin);
        end
    end
end

% Init speed.
xyv(newones) = vmean/sqrt(pi/2).*irandn(size(xyv(newones)));

xym = xym(:); % Make sure only first dimension.
xyv = xyv(:);