你好 Hi
我叫Rick Gentile，是相控阵系统工具箱的产品经理 My name is Rick Gentile on the product manager for the phased array system Tool box.
我想告诉你生成雷达数据立方体是多么容易 I want to show you how easy it is to generate a radar data cube.
使用Matlab中的相控阵系统工具箱 Using Matlab in the phased array system toolbox,
你可以找到雷达的详细描述。 You can find a good description of the radar.
Mark A. Richards的数据立方体和雷达信号处理基础 Data cube and fundamentals of radar signal processing by Mark A. Richards.
在这本书中 In this book
他描述了雷达数据立方体是一种方便的方法来表示在空间和时间上逐样本建立的雷达接收信号 He describes the radar Data cube is a convenient way to represent a collection of received radar signals built up sample by sample in space and time.
将接收到的数据放入这个数据立方体的格式中 At once the received data is put into this data cube format.
各种信号处理技术可以用来提高目标的回波 Various signal processing techniques can be used to enhance the target returns,
从数据中提取距离、速度和方位信息 An extract range speed and bearing information from the data.
这些技术包括：脉冲压缩技术 These techniques include algorithms such as pulse compression,
多普勒处理和波束形成技术。 Doppler processing and beamforming.
但是，建立一个雷达数据立方体需要一些东西 So to build up a radar data Cube will need a few things.
我们先从目标反射的单个脉冲开始 We'll start with a single pulse that is reflected off the target.
接收到的数据及时采样 The received data is sampled in time,
样本可以用来计算目标的距离 The samples can be used to calculate the distance of the target.
这些时间样本有时被称为距离单元 These time samples are sometimes called range bins.
它们构成数据立方体的Y轴 They make up the Y axis of the data cube.
被称为快时间维， This is referred to as the fast time dimension,
这是因为采样率有时会很高，从数十MHz到10GHz甚至更高。 because the sampling rate can sometimes be pretty high from the tens of megahertz to ten Gigahertz or higher.
单个雷达目标的回波通常会被收集到一组接收阵元中 A single radar target reflection will often be collected in a ray of receive elements.
每个阵元构成了单独的通道 Each one of these elements makes up individual channel,
就是图中雷达数据立方体的X维 Which makes up the X dimension of the radar data Cube in the figure.
特别是像这样对接收信号进行采样，我们就能确定目标的方位 Especially sampling the received signals like this will allow us to determine the bearing of the target.
如果我们在到达角(DOA)的估计中使用像波束形成这样的算法 If we use algorithms like beamforming in direction of arrival Estimation.
你可以在选定的方向上以一定的脉冲重复频率(PRF)发送和接收多个脉冲 You might be transmitting and receiving multiple pulses in a selected direction at a rate called the Pulse Repetition Frequency
脉冲集的时间有时被称为相干处理间隔(CPI) The time base for a collection of pulses is sometimes called the coherent processing interval,
这将是一个比距离门采样低得多的速率 And this will be a much lower rate than the range gate sampling.
所以1到10KHz的脉冲重复频率是一个典型的范围 So pulse repetition frequencies of one to ten kilo hertz would be a typical range.
这是雷达数据立方体的一个维度 This is the dimension of the radar data Cube.
它有时被称为慢时间维度。 It is sometimes called a slow time dimension.
从这组数据中获得的信息可以用来确定目标的速度 The information you get from this collection of data is something you can use to determine the speed of the target.
让我们看看如何在实验中做到这一点 Let's take a look at how we can do this in my lab.
好 OK
我们会发现产生脉冲波形相对容易 We'll see that it's relatively easy to generate pulse wave forms
发射脉冲 Reflect the pulse
照射目标并将接收到的信号收集到雷达数据立方体中 Sought the target and collect the received signals into the radar data cube.
这是我们可以用来建立自己的雷达数据立方体的Matlab代码 I here's the Matlab code that we can use to build our own radar data cube.
我们来看看相控阵系统工具箱 We'll take a look at some phase array system toolbox,
可用于创建目标的函数和系统实例 Functions and system objects that can be used to create a target.
以每秒150米的速度行驶30公里 At a thirty kilometers distance in one hundred and fifty metres per second speed.
现在这里有另一个相控阵系统工具箱实例 我们可以用来创建一个八阵元阵列 Now there's another phased array system toolbox object here that we can use to create an eight element array,
所以我们的数据立方体将有八个接收通道 So our data cube will have eight received channels.
这是我们的方式 Here's our way form,
它是一个线性调频脉冲，占空比为10% Which is a swept FM pulse with a ten per cent duty cycle.
你可以看到 You could see.
波形的采样率是1MHz The sample rate for this waveform is one megahertz,
PRF是1KHz. And the PRF is one kilo Hertz.
这意味着每个雷达脉冲有1000个采样点 This means there will be a thousand samples per radar pulse.
这将构成我们雷达数据立方体的时间维度 This will make up the time dimension of our radar data cube.
我将运行这段代码，你将看到它需要大约40行代码 I'll run this piece of code and you'll see it takes about forty lines of code.
我们在Matlab实例上创建的内容 What we've created on the Matlab objects,
在Matlab工作区的窗口可以看到 Which can be seen in Matlab workspace window over here.
这些实例将用来仿真和生成我们的雷达数据立方体。 These are the objects will use to simulate and generate our radar data cube.
现在雷达数据立方体的实际生成只需要大约15行代码 Now the actual generation of the radar data cube only takes about fifteen lines of code.
你可以在仿真循环中看到，这里有32个脉冲 You can see it in the simulation loop here that there are the 32 pulses.
这里显示的是循环大小 This is the size of the loop shown right here.
这个循环产生雷达脉冲，更新目标位置，发射我们产生的脉冲 照射目标并反射回波到雷达 This loop generates the radar pulse and updates the target position and propagates the pulse we generated and reflects off the target and propagates back to the radar.
尽管所有这些回波都是收集的 Though all of these returns are collected,
它们实际上是在雷达中收集的 They are actually collected right here in the radar.
此时可以组装数据到多维数据集 Data cube can be assembled at this point.
当我运行这段代码时 When I run this piece of code,
我构造了雷达数据立方体 I produced my radar data cube.
我们可以看到雷达数据立方体的尺寸 We could see over here that the dimension of the radar data cube.
在这里 Is here,
这些复数I/Q采样是在8个阵元的阵列 And there are complex I/Q samples that are collected at the array and the dimensions or a thousand times
以及32个脉冲上收集的 Samples by eight receive elements by 32 pulses.
这是整32个脉冲在一个通道上接收到的信号的曲线图 And this is a plot of a signal received for one channel for the entire 32 pulsation.
现在您可能认为第一个仿真是一个小数据立方体 Now you might think that the first simulation was a small data cube.
所以，让我们稍微增加一点复杂度 So let's increase the complexity a little bit.
下一个例子 This next example,
不是只有一个目标 Instead of having one target,
我们将有20个随机位置和速度的目标 We're going to have twenty targets with random positions and velocity.
接收阵列将是121个阵元安装在一个球体的表面 I receive a ray will be one hundred and twenty one elements mounted on the surface of a sphere.
同时 Also,
我们把波形的带宽从1MHz增加到了20MHz， We've increased our bandwidth of the wave form from one megahertz of twenty megahertz.
以适合更多的解决方案 To give us additional resolution.
与前面的示例相比，初始化代码多了几行 The initialization is a few more lines of code than our previous example.
您可以在这里看到我们在这个阵列的几何图形 You can see the array geometry that we have in this plot here.
您还可以看到构建此数据多维数据集的循环与前面的示例相同 You can also see the loop to build this data Cube is identical to the previous example.
唯一的区别是，我们为RCS传递的值和位置是向量 而不是为单个目标传递的单个值 The only difference is that the values that we pass in for the rcs and the positions are vectors instead of just a single value for for a single target.
我继续执行这段代码 I'll go ahead and execute this code.
生成新的数据立方体 To generate our new data cube,
我们可以看到新数据立方体的维度是121个接收阵元，两万个时间采样点 We can see the dimensions of the new data Cube is twenty thousand time samples across a hundred and twenty one receive elements
以及32个脉冲 And thirty two pulses are the dimensions of grown.
但如果你对我们如何处理雷达数据立方体来确定距离速度和方位感兴趣的话，现在仍然很容易生成 But it's still easy to generate now if you're interested in how we can process a radar data cube to determine the range speed and bearing from this data Cube,
请观看第二部分：处理雷达数据立方体 Please watch part two of this recording title processing the radar data Cube.
您可以在我们的网站上的相控阵系统工具箱产品页面上找到 You can find this on our website at the phased array system Toolbox product page.
非常感谢你抽出时间来观看！ Thank you very much for your time.