雷达多径回波信号来实现狭小空间中运动目标的多普勒检测

function [ k, R ] = wall(radar_pos, theta, target_pos, target_size) R = inf; % Return 0 range if no detection is made scene_x = 30; % Plot x dimension in m scene_y = 15; % Plot y dimension in m radar_pos = radar_pos; % x y position of the radar %M = 1; % Number of bounces considered %target_pos = [10 7]; theta = theta; % angle of radar beam in degrees wall1_x = 7; % x coordinate of wall 1 wall1_y = 5; % y coordinate of wall 1 wall2_x = 5; % x coordinate of wall 1 wall2_y = 8; % y coordinate of wall 1 subplot(2,1,1) hold on; plot([wall1_x, wall1_x, scene_x], [0, wall1_y, wall1_y], 'k'); % plot wall 1 plot([wall2_x, wall2_x, scene_x], [scene_y, wall2_y, wall2_y], 'k'); % plot wall 2 %% Plot the target plot([target_pos(1) - target_size / 2, target_pos(1) + target_size / 2], [target_pos(2), target_pos(2)]); %% Begin painful geometry k = 0; if tand(theta) * (wall2_x - radar_pos*(1))+radar_pos(2) > wall2_y % beam overshoots the gap s = tand(theta) * (wall2_x - radar_pos(1))+radar_pos(2); % y-position where beam hits wall face plot([radar_pos(1), wall2_x, 0], [radar_pos(2), s, tand(theta) * (wall2_x - radar_pos(1)) + s]); elseif tand(theta) * (wall1_x - radar_pos(1)) + radar_pos(2) < wall1_y % beam undershoots the gap s = tand(theta) * (wall1_x - radar_pos(1)) +radar_pos(2); % y-position where beam hits wall face plot([radar_pos(1), wall1_x, 0], [radar_pos(2), s, tand(theta) * (wall1_x - radar_pos(1)) + s]); else s = (wall2_y - radar_pos(2))/tand(theta) + radar_pos(1); % x-position where beam hits upper wall x_inc = (wall2_y - wall1_y)/tand(theta); % x-value increment for each bounce [M, hit_status] = target(radar_pos(1), radar_pos(2), target_pos(1), target_pos(2), target_size, wall1_y, wall2_y, theta); % first segment to the target k = M; if M == 0 % beam hits target before walls s = (target_pos(2) - radar_pos(2))/tand(theta) + radar_pos(1); % x-position where beam hits target plot_y = [radar_pos(2), target_pos(2)]; else plot_y = [radar_pos(2), wall2_y]; end plot_x = [radar_pos(1), s]; while M > 0 if M > 1 plot_x = [plot_x, s + x_inc, s + 2*x_inc]; plot_y = [plot_y, wall1_y, wall2_y]; s = s + 2 * x_inc; M = M-2; % stop last reflection at target if and(~M, hit_status) plot_y(end) = target_pos(2); plot_x(end) = ((target_pos(2) - wall1_y)/(wall2_y - wall1_y)) * x_inc + plot_x(end -1); s = plot_x(end); end else plot_x = [plot_x, s + x_inc]; plot_y = [plot_y, wall1_y]; s = s + x_inc; M = M - 1; % stop last reflection at target if and(~M, hit_status) plot_y(end) = target_pos(2); plot_x(end) = ((wall2_y - target_pos(2))/(wall2_y - wall1_y)) * x_inc + plot_x(end -1); s = plot_x(end); end end end plot(plot_x, plot_y); if hit_status R = (s - radar_pos(1))/cosd(theta); else R = inf; end end drawnow hold off pause(0.000000001) scatter(radar_pos(1), radar_pos(2)); % scatter(target_pos(1), target_pos(2)); % Plots a point at center of % target xlim([0, scene_x]); ylim([0, scene_y]); % saveas(gcf,sprintf('images/fig%d.png', theta))