在传统用例中，物联网（IoT）实施的实现足够挑战，这些无线设备网络：各个行业的农业，工业，智能城市和其他应用程序。但是，当该位置是移动设备并具有运输车辆的RF动力学时，部署物联网会达到另一个复杂性。车辆物联网是一个物联网的快速出现区域，该区域是由组织需要将火车，卡车，船只，汽车和其他车辆转变为具有下一代连接的无线通信枢纽的驱动。在本文中，Laird Connectivity的Ted Hebron讨论并消除了关于车辆物联网新兴领域的11个神话。
1. This is just a new term for something that’s existed for a while. Vehicles have always had wireless technologies.
是的，无线技术在从供应链卡车到乘用车的车辆中并不是什么新鲜事。但是，这些运输车辆和舰队中的无线技术正在向前迈进。曾经拥有一两个无线技术和设备的车辆现在正在升级，以用作无线协议，无线设备和应用程序的无线通信集线器。例如，如果您在18轮或警察巡洋舰的机舱内看一看，您现在越来越多地发现的是一种物联网环境，就像工业工厂中的物联网一样“繁忙”和复杂。
2.是的，但是物联网是车辆的错误称为；“物联网”一词应保留用于其他部署。车辆是不同的鱼水壶，应该有不同的术语。
绝对是，过去几年中，大多数物联网部署都集中在与工厂，工厂，农业应用等截然不同的环境中的用例。但是对我来说，物联网比任何特定用例都要广泛。无论设置如何，IOT都有资格成为“物联网”，这是一个事实，即多个无线技术需要以集成的方式一起工作，支持一系列无线设备并在复杂的RF环境中成功运行。这些场景需要真正的物联网策略，并且车辆绝对适合该描述。
Vehicles like trucking fleets, cargo trains, and freight-carrying airplanes are being outfitted with an increasing number of wirelessly connected devices and wirelessly enabled applications that require a sophisticated vehicular IoT system. The IoT implementations include diagnostic systems, environmental sensors, physical security devices, temperature-control sensors, product-tracking capabilities, enhanced communications systems, worker safety devices, mobile computing devices, and more. All require a multi-technology wireless environment with technologies such as Wi-Fi, Bluetooth, cellular, GPS, and LoRa.
3. I can understand a police cruiser or an ambulance fitting into this category, given the number of devices that first responders have in their vehicles. But a vehicle with Wi-Fi for passengers is a much simpler RF environment.
在许多方面，仅使用Wi-Fi的无线实现将更简单，但是我们看到的车辆无线实现不仅仅涉及给孩子为他们的平板电脑提供可靠的Wi-Fi信号。乘用车，班车，班车，火车，城市公共汽车等，可能会为乘客提供Wi-Fi作为他们最明显的无线技术，但今天并不孤单。
这些车辆配备了复杂的无线系统，这些系统具有多种技术，并支持一长串售票机，使用/容量报告系统，数字标牌，位置跟踪，驾驶员调度通信，安全/安全系统等。所有这些元素都使这些真实的物联网环境。
4.如果我在其他环境中从事传统的物联网部署工作，那么车辆的挑战将相同。
是的，其他物联网项目的许多最佳实践将继续成为您在车辆IoT项目上的资产。是的，您将使用许多相同的技术。但是在许多情况下，车辆物联网将推动您过去的物联网经验的界限。例如，可能会要求您使用没有发挥作用的无线技术，例如工业环境。
为了说明这一点,让我们看看警察巡洋舰。It’s a timely topic because tens of thousands of first-responder vehicles in the U.S. are having their wireless systems upgraded right now in order to utilize the FirstNet cellular network devoted to public safety agencies. These upgrades typically involve a range of enhancements beyond simply FirstNet connectivity, and it underscores the complexity of vehicular IoT: A police cruiser will not only have FirstNet connectivity, but also Wi-Fi, Bluetooth, GNSS, UHF, 4G/5G, and other technologies co-located in the same vehicle. Those technologies must then work in an integrated fashion to support a growing list of devices and applications, including body cams, voice communications, high-def video access, facial detection, laptop connectivity, tracking devices, and more.
5.在工业和医疗等环境中，为车辆进行计划要简单，从现在开始，您需要进行未来的预期。
在那些环境中，未来的防护确实很重要，因为必须经常升级传感器和无线系统的成本和实际困难。车辆也是如此，但出于某些特定原因。一个是从场上拉动车辆以执行天线和无线系统升级的困难。当升级包括整个车队，例如公用车或国家航运舰队时，这将被放大。组织希望最大程度地减少这些升级的停机时间，这意味着物联网实施需要预测未来的无线应用程序，并确保适当的技术支持它们。
我还应该注意，在车辆中添加另一个天线通常会完全改变RF动力学，从而对其他所有天线的性能产生负面影响。因此，工程师必须进行详细的建模和测试，以确定是否可以添加其他天线以及可以将其放在车辆上。同样重要的是，应该仔细地进行安装以防止水入侵，因为额外的天线需要在车辆外部额外的孔。水分侵入的风险不可忽略，这就是为什么应该谨慎添加更多天线的原因。
6.物联网是物联网。车辆中的RF挑战与工厂或医院病房的挑战并没有太大不同。
Many common challenges exist between all of these environments, but vehicles present very specific challenges because of the prevalence of metal surfaces and the congestion of wireless signals in a small space. Vehicles typically have multiple metal surfaces in close proximity to the antennas and devices. These metal surfaces become obstructions, which can negatively affect antenna performance. That challenge is compounded by how many antennas and devices are operating in a relatively small space. RF modeling and testing are critical to understanding the RF dynamics associated with antenna selection and antenna placement in light of these obstacles.
7.实现最佳的RF性能是将天线安装在车顶上。
确实如此，但是现有的屋顶天线/结构和屋顶材料组成在天线选择和放置中起着重要作用。对于许多屋顶天线安装，屋顶是天线的接地平面，该地面上的位置会显着影响RF性能。相反，非金属表面将需要选择无依赖地面平面的天线。无论您是否具有地面依赖/独立天线，其他天线都使天线位置复杂化，应通过RF建模和测试来验证。
8. The RF dynamics of vehicles is pretty similar, so if I’ve worked on one, I know what I need to know.
That’s true if you’re working on an identical model of a given set of planes, trains, and automobiles. But even similar vehicles can have dramatically different RF dynamics due to the way they were designed, the types of materials used, the interior layout of the model, etc.
例如，汽车型号在外部看起来相似，但是如果制造商决定制造一个面板玻璃纤维或塑料而不是金属，则RF动力学可能会大不相同。并且可能以类似方式改变RF动力学的车辆之间可能存在其他不对的差异。因此，RF测试对于确保天线及其位置以所需的方式执行至关重要。
9.由于车辆在移动中如此多，因此高的天线是保持连通性的理想选择。
Antenna height is no longer a good indicator of performance in vehicles. Low-profile antennas have outstanding performance in a much smaller form factor than the kinds of antennas typically found on vehicles in the past. But a low-profile antenna also makes sense from a very practical point of view—antennas are easily damaged by trees, bushes, wind, people, tunnels, and other obstacles. Low-profile antennas are less likely to be damaged by those dangers, avoiding costly and time-consuming repairs.
10.除了担心树木的损害外，使用车辆天线的工作与其他物联网实施一样，对吗？
还有另一个问题要仔细观察：除非工程师在车辆中进行了许多无线实施，否则他们可能会对车辆物联网所涉及的电缆长度感到惊讶。电缆比大多数其他物联网项目更长，可能导致影响性能的衰减问题。从事这些项目的工程师应仔细选择组件，电缆和天线以减轻衰减。
11.如果我不为大型车辆制造商工作，那么我不太可能参与任何车辆IoT项目。
Yes, lots of wireless systems going into transportation vehicles are installed by the OEM in the factory where it’s originally assembled. But many of these systems are being installed in the aftermarket, with those projects led by engineering firms that work across a variety of industries rather than being vehicular specialists.
例如，无线升级到第一响应器车辆通常是由本地工程公司而不是OEM进行的。The same is true for wireless installations in trucking fleets that are already in service, mass transit vehicles that are in operation, etc. This is a fast-emerging category of IoT, and it requires a design and engineering strategy that’s tuned to the specific challenges of implementing IoT in vehicles.
Ted Hebron is Senior Product Manager forLaird连接性。
