解释 Data_range(1:NTS/2,:) = tmp(NTS/2+1:NTS,:)
时间: 2023-05-29 20:05:58 浏览: 58
这段代码是将一个名为tmp的矩阵的后半部分(从第NTS/2+1行到最后一行)赋值给名为Data_range的矩阵的前半部分(从第1行到第NTS/2行)。其中,冒号“:”表示所有列。因此,该代码将tmp矩阵的后半部分的所有列复制到Data_range矩阵的前半部分的对应位置。
相关问题
clc;clear; wm=1; wc=wm; Ts=pi/wm; ws=2*pi/Ts; n=-100:100; nTs=n*Ts f=2*sinc(nTs/pi); Dt=0.0025;t=-15:Dt:15; fa=f*Ts*wc/pi*sinc((wc/pi)*(ones( length(nTs),1)*t-nTs'*ones(1, length(t)))); t1=-15:0.25:15; f1=2*sinc(t1/pi); subplot(121); stem(t1,f1); xlabel('kTs'); ylabel('f(kTs)'); title('sa(t)=sinc(t/pi)的临界抽样信号'); subplot(122); plot(t, fa) xlabel('t'); ylabel('fa(t)'); title('由sa(t)=sinc(t/pi)的临界抽样信号重构sa(t)'); grid;
这段代码是关于信号的抽样和重构的,其中采用了临界抽样,信号为基带信号,经过抽样后进行重构。抽样定理告诉我们,如果采样频率大于等于信号的最高频率的两倍,就可以完美地还原原始信号。在这段代码中,采样频率为 $\omega_c=\omega_m=\pi/T_s$,即采样间隔为 $T_s$,信号为 $s_a(t)=\operatorname{sinc}(t/\pi)$,经过采样后重构出来的信号为 $f_a(t)$,可以看到重构后的信号与原始信号非常接近。
% Ballistic missile trajectory & SINS/GPS simulation glvs ts = 0.01; %% trajectory simulation % stage 1: 1/4 circle T = 60; t = (0:ts:T)'; afadot2 = 2*pi/2/T^2; afa = 1/2*afadot2*t.^2; r = 60000; y = r-r*cos(afa); z = r*sin(afa); pitch = pi/2-afa; tt = t; % stage 2: leveling constant acceleration v = (y(end)-y(end-1))/ts; T = 120; t = (ts:ts:T)'; a = -2; y = [y; y(end)+v*t+1/2*a*t.^2]; z = [z; z(end)+t*0]; pitch = [pitch; t*0]; tt = [tt; tt(end)+t]; % stage 3: leveling constant velocity v = (y(end)-y(end-1))/ts; T = 120; t = (ts:ts:T)'; a = -0; y = [y; y(end)+v*t+1/2*a*t.^2]; z = [z; z(end)+t*0]; pitch = [pitch; t*0]; tt = [tt; tt(end)+t]; myfig, plot(y, z, '-'); xygo('front/m','up/m'); %% imu,avp,gps dxyz = [y*0,y,z,tt]; dxyz(:,1:3) = ar1filt(dxyz(:,1:3), 100); pos = dxyz2pos(dxyz); ap = [pitch, zeros(length(pos),2), pos]; [imu, avp0, avp] = ap2imu(ap); imuplot(imu); gps = gpssimu(avp(1:100:end, :), 0.1, 10, 1,0,0, 0); %% sins/gps imuerr = imuerrset(0.15, 100, 0.001, 10); davp = avperrset([1;1;3]*3, [1;1;1], [1;1;3]*100); imu1 = imuadderr(imu,imuerr); ins = insinit(avpadderr(avp0,davp), ts); ins.nts=ts; avp1 = sinsgps(imu1, gps, ins, davp, imuerr); avpcmpplot(avp, avp1(:,[1:9,end]), 'phi');帮我注释代码
以下是对代码的注释:
```matlab
% Ballistic missile trajectory & SINS/GPS simulation
glvs ts = 0.01; % 设置时间步长
%% 轨迹模拟
% 阶段1:1/4圆形轨迹
T = 60; % 转弯时间
t = (0:ts:T)'; % 时间向量
afadot2 = 2*pi/2/T^2; % 角速度
afa = 1/2*afadot2*t.^2; % 角度
r = 60000; % 距离
y = r-r*cos(afa); % y坐标
z = r*sin(afa); % z坐标
pitch = pi/2-afa; % pitch角
tt = t;
% 阶段2:匀加速直线运动
v = (y(end)-y(end-1))/ts; % 初始速度
T = 120; % 时间
t = (ts:ts:T)'; % 时间向量
a = -2; % 加速度
y = [y; y(end)+v*t+1/2*a*t.^2]; % y坐标
z = [z; z(end)+t*0]; % z坐标
pitch = [pitch; t*0]; % pitch角
tt = [tt; tt(end)+t];
% 阶段3:匀速直线运动
v = (y(end)-y(end-1))/ts; % 初始速度
T = 120; % 时间
t = (ts:ts:T)'; % 时间向量
a = -0; % 加速度
y = [y; y(end)+v*t+1/2*a*t.^2]; % y坐标
z = [z; z(end)+t*0]; % z坐标
pitch = [pitch; t*0]; % pitch角
tt = [tt; tt(end)+t];
% 绘制轨迹图
myfig, plot(y, z, '-');
xygo('front/m','up/m');
%% IMU、AVP和GPS
% 计算位置
dxyz = [y*0,y,z,tt];
dxyz(:,1:3) = ar1filt(dxyz(:,1:3), 100);
pos = dxyz2pos(dxyz);
% 计算姿态
ap = [pitch, zeros(length(pos),2), pos];
[imu, avp0, avp] = ap2imu(ap);
% 绘制IMU图
imuplot(imu);
% 生成GPS数据
gps = gpssimu(avp(1:100:end, :), 0.1, 10, 1,0,0, 0);
%% SINS/GPS
% 设置IMU误差和姿态误差
imuerr = imuerrset(0.15, 100, 0.001, 10);
davp = avperrset([1;1;3]*3, [1;1;1], [1;1;3]*100);
% 添加IMU误差
imu1 = imuadderr(imu,imuerr);
% 初始化INS
ins = insinit(avpadderr(avp0,davp), ts);
ins.nts=ts;
% 进行SINS/GPS解算
avp1 = sinsgps(imu1, gps, ins, davp, imuerr);
% 绘制姿态角度对比曲线
avpcmpplot(avp, avp1(:,[1:9,end]), 'phi');
```