A paradigm shift in wireless LAN-based location tracking

我仍然记得我第一次理解“范例转移”。 我已经是一个成熟的成年人,孩子们n and a university degree and finally found some time to read a short story in the book “Seven Habits of Highly Effective People“ 经过Stephen Covey(pages 30-31)in which he describes a shift in his paradigm, or world view.

上个月，我在拉斯维加斯的Aruba Masterere享有类似的经验，内容涉及他们关于Aruba的新位置解决方案的公告。 

After first hearing a marketing presentation on yet one moreNew Thing在基于Wi-Fi的位置跟踪解决方案中。我准备好了extremely skeptical。 

First, a bit of background.

在过去的二十年中，我生活，安装，固定和删除了各种各样的实时位置解决方案（RTLS）……我们中的许多人都从事无线LAN行业。 

Entire companies have launched, thrived, declined, then failed over these past twenty-plus years of RTLS. The siren song of being able to find and track people and things has been so tempting - and continues to be as we attempt to solve this known demand with our customers.

In the paradigm shift story from Stephen Covey, he hears a single sentence from a distraught father on a New York subway car and it changes his entire outlook on the situation. 

对我来说，我对位置跟踪的范式转变是在斯图亚特·斯特里克兰和查克•卢卡斯表示ewski。In a single sentence, they turned the entire world of Wi-Fi based location tracking upside down and my world view changed. 

The trigger sentence was: “该新解决方案不是基于任何预先存在的地图或平面图，而是基于国际纬度和经度标准。” Let that sink in for a minute… 

I’ll wait.

好的，我花了几分钟才能理解看似很小的差异对位置跟踪的含义。 

我们的RTLS系统不再基于一些进口地图或平面图，而是可以在世界现有的导航结构中工作。 This does mean some fundamental changes in how we go about doing RTLS within the Wireless LAN community.

首先，让我谈谈什么不是…… 

It does NOT mean “Indoor GPS”

尽管来自Aruba的新的Wi-Fi 6e访问点确实包含GNSS芯片组，并且可以在室内使用这些“位置”芯片进行自我放置，但这并不意味着此Aruba解决方案为客户的客户设备提供了“室内GPS”。

Sidebar Note:GPS和GNSS有什么区别？GPS traditionally refers to the North American Global Positioning System. Global Navigation Satellite System or GNSS refers to the International Multi-Constellation Satellite System. GNSS typically includes GPS, GLONASS, Baidu, Galileo and other constellation systems.

When people refer to GNSS, they are referring to all available satellites for global positioning.

这并不意味着“没有更多的调查”

Though this solution of ‘self-locating’ access points - if you have either all Aruba AP-500’s or AP-600 series access points - does not mean the variety of ‘surveys’ we have been doing for decades suddenly disappear.

There has been a lot said about the terrible word ‘survey’ when referring to things we do in the WLAN community. Predictive designs, AP on a Stick designs, Post-Install Validation and Troubleshooting all will continue as they have in the past.

If you were a company who used the word ‘survey’ to include the process of documenting access point locations on a map… then perhaps this new self-locating access points may save that one type of ‘survey’. Thus RTLS surveys may now be eliminated.

这并不意味着“智能手机现在知道它们在室内的位置”

In the beginning… Yet, this solution does offer a much better baseline for software developers to work from. Including the ability for certain OS vendors who use a generic call to the OS to ‘find my location’ that would allow for to OS to switch between different forms of location tracking using standard latitude/longitude metrics.请参阅上面的室内GPS。

What it does mean…

This new paradigm shift does mean Aruba’s new AP-6xx series Wi-Fi 6E access points will have the ability to know where they are in the world, even indoors.

This means they will be ready to implement Standard Power after the FCC approves the process since they require 6GHz capable access points to auto locate themselves to meet the Standard Power requirement. 

Additionally, those who have an installed base of Aruba’s AP-500 series access points can also use this new technological solution to auto-locate within VisualRF and have access to these new location features. (With some additional manual placement of anchor access points)

这也意味着Aruba现在将其作为开放定位计划提供给世界，以便整个社区可以受益并与之合作，以帮助解决我们几十年来一直在工作的位置问题 - 但是这次共同使用全球标准参考。 

How it works

这是一个very roughreview of the process. Please read further information from Aruba’s website, Aruba Atmosphere session presentations, and product information for more details and descriptions.

Since the beginning of navigation, we needed at least two things to find where we were located. First a fixed known location, and second the differences between that known location and where we are now.

Pre-GPS, navigators used stars, the Sun, and a whole lot of math to figure these things out.

For this new location solution from Aruba, the first step is to have a handful of AP-600-series access points, with built-in GNSS chips work to find out where they are in the world.

我们对室内全科医生遇到了问题，基本上是永远的。由于GPS卫星在天空中数千英里处，而且它们的无线电信号极为弱，并且很容易受到室内多路径和衰减问题的影响。

This new Aruba location system addresses these a couple of ways. First, they take theirtimeto get it right. Satellites pass overhead and for an indoor access point, may only have a brief, and possibly obstructed view of a satellite’s path across the sky. Yet unlike handheld GPS devices or smartphones with internal GPS, these access points can take their time and wait… wait for hours instead of seconds to acquire these signals.

此外，而且非常重要的是，所有这些配备有Aruba Central的GNSS芯片组的访问点都可以相互交流。分享有关他们看到的卫星的信息，向其他人学习有关精确的正时触发器的信息，并在他们经过头顶时进入更多的卫星。

这与速度无关……而是准确性。几个小时后，几个访问点了解了世界上的位置。精度为1米！

Next – and while the other is going on – ALL the access points use another 802.11 standard, perhaps not used very much by others, but a standard nonetheless, that supports something called Fine Timing Measurement. This FTM figures out the approximate distances between access points.

At this point there is a lot of math going on. Matrix math to figure out the best fit for the FTM measurements while working with the fixed latitude/longitude of those handful of fixed location access points.

最后，该组中的所有访问点都将在精度1-2米之内知道它们的纬度和经度，然后可以在VisualRF中的平面图上自动放置自己。

净结果

毕竟这些技术和大量数学 - 阿鲁巴接入点将知道他们在世界上的位置，具有非常精确的纬度和经度估计。

那高度呢？

众所周知，GPS系统在准确的高度测量方面一直很糟糕，尤其是当指标已绑定到平均海平面作为基线海拔。可以用地球数据集叠加从GNSS数据中收集的数据，并计算出高于高程测量值的精确且有用的高度。

Instead, Aruba has access to other information found during the FTM calculations to place groups of access points in ‘layers’ – so all AP’s in a given floor will already be grouped together, and this tied with floor-based naming conventions as a check and balance can do quite well in layering access points on their appropriate floor.

Sidebar Note:The current FCC requirement for automatic geolocation of 6GHz Access Points only applies to a 2D or latitude and longitude to meet their Standard Power requirements. While elevation is also required to be sent to the AFC System, the rules allow this to be manually set by an installer.

What is next?

这只是这个新的Aruba位置解决方案的首次公告。将会有更多的解决方案，与客户端设备OS供应商的更多集成以及与其他RTLS软件解决方案集成。

现在，我们生活在一个世界上，我们关于室内位置工作方式的范式已经发生了巨大变化！

A couple of resources for further study:

Self Locating Wireless Access Points Overview

Self Locating Access Point Solutions Overview PDF