哪种车用无线技术是汽车厂商的菜？

根据业界消息，汽车制造商虽然十分渴望无线技术，但并未打算在短时间内采用 Wi-Fi / 蓝牙(Bluetooth) 组合芯片。有鉴于汽车产品的开发周期以及产品本身生命周期都比手机长得许多，无线技术进军汽车市场的脚步也是渐进式的。 根 据市场研究机构IHS的最新统计，车用无线市场预期在2018年至2012年之间成长40%以上；当无线技术已经广泛渗透已开发国家的家用市场，汽车市场自然成为无线技术供货商们下一个兵家必争之地──为何那些保守的车厂开始拥护包括蓝牙、Wi-Fi等车内无线技术？当然也与人们带到车内的自用无线设备有关。 USB、 Aux等连接埠以及一些专属连结方案已经进驻汽车，因此人们可以将自己的手持式设备插在车子里；不过IHS资深分析师Luca DeAmbroggi表示，一旦消费者开始寻求将资料──透过网际网络下载到手机或平板设备的──传输到后座显示器或是车内其它设备，车厂也正在试图以蓝牙(已经装备在车内)或是Wi-Fi来执行这类内容传输任务。 DeAmbroggi特别澄清，他并不认为无线技术将取代现有的车内有线连结方案，例如车用资通讯娱乐设备的USB，以及CAN、FlexRay或是车用以太网络，以及针对行车安全、先进驾驶辅助系统(ADAS)等设备运用之车内摄影机所装设的嵌入式连结。不过他也指出，整体车内无线技术的应用正在起飞。

全球车用无线市场营收预测 (单位：十亿美元；IHS，2013年7月)Q1Besmc

举例来说，在汽车市场，USB衍伸的有线连结解决方案正：“面临车内无线机制的挑战，包括针对固网与移动设备之间短距离数据传输的蓝牙，以及针对双向无线资通讯娱乐设备联机的嵌入式蜂巢式技术。”DeAmbroggi表示。 车内蓝牙我们当然知道，不过问题在于，当世界其它应用领域正迅速转向采用速度更快的下一代Wi-Fi或功耗更低的蓝牙时，汽车厂商将采用哪种版本的无线技术？ 对此DeAmbroggi指出，汽车厂商正在考虑采用蓝牙4.0版(以蓝牙低功耗技术为基础)以及802.11ab；他解释，蓝牙4.0可藉由HS (high-speed)选项将提供更高的传输速度，同时确保电子设备维持更长时间的配对状态、所消耗的功率则较低。 不过当然，无论是蓝牙4.0或是802.11ab，都具备传输大型资料──例如车载摄影机所拍摄的视频，高画质且无压缩──的能力。再加上，当消费者希望将智能手机上的HD视频串流至后座显示器，这两种无线技术都能支持。 本文授权编译自EE Times，版权所有，谢绝转载 本文下一页：为何车厂不能用Wi-Fi/蓝牙组合芯片呢？

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• 骇客们有可能这样控制你的汽车……
• 村田：我们在车载用连接性技术上的努力
• 防堵车保安全，Wi-Fi有望进入汽车Q1Besmc

{pagination} 日本大厂Panasonic在去年从发表过一款采用WiGig技术的汽车后装市场无线产品，支持透过60GHz频段、达到7Gbps的数据传输速率；在发表会时，该公司示范了一位汽车乘客将平板设备上的多媒体内容传送到后座的显示器上播放，此外车上计算机的信息内容也能传送到平板设备上，让乘客检查例如胎压、 电池电量等汽车信息。

Panasonic示范车用WiGig技术Q1Besmc

虽然Panasonic的示范看来很吸引人，但DeAmbroggi 并不认为该技术已经进入商业市场。而尽管目前有各种不同的车用无线技术仍被考虑中，有一件事情是可以肯定的：只要消费者的行动设备被用来当作上网的桥梁并下载更多内容，他们就会一直需要流量更大、速度更快的无线技术，他们的胃口是难以被满足的。 DeAmbroggi表示，关于车用无线技术的难题，最低限度是要确保车内会有Wi-Fi，如此才能透过蓝牙切换至Wi-Fi，让满溢的资料流被转移出去；不过他也不确定汽车厂商是否会 偏好将蓝牙与Wi-Fi两种技术分开考虑，或者是选择组合方案以最佳化成本并降低设计复杂度。 而目前几乎所有的智能手机都采用Wi-Fi/蓝牙组合芯片，为何车厂不能用呢？DeAmbroggi对此表示：“首先，那些手机用的组合芯片并非车规。”其次：“我的考量是与成本有关，就算无线技术的广泛扩散显示未来将会使用整合式组合芯片，至少在短期之内，独立式芯片是比较可能的方案。” 这是因为汽车应用对Wi-Fi技术的影响力有限：“Wi-Fi的整合方案仍仅限于高阶车款的应用。”DeAmbroggi指出，汽车厂商正在权衡成本、使用者情境(针对平板设备与智能手机在车内的应用)，以及使用者对频宽的需求。 此外就算无线技术会被应用于汽车内，DeAmbroggi表示有一些议题是需要在技术安装之前被考量的，包括因为不同无线频段、区域差异以及规格带来的信号接收、电磁干扰、系统复杂度增加等等问题，这些变量都将会影响无线系统与内部零组件的成本。 本文授权编译自EE Times，版权所有，谢绝转载 编译：Judith Cheng 参考英文原文：In-Car Wireless Rises, but Don't Hold Your Breath，by Junko Yoshida

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• 防堵车保安全，Wi-Fi有望进入汽车Q1Besmc

{pagination} In-Car Wireless Rises, but Don't Hold Your Breath Junko Yoshida MADISON, Wis. -- News flash. Automakers are going wireless big time. But they are not likely to use WiFi/Bluetooth combo chips anytime soon. The automotive wireless market is projected to expand by more than 40 percent from 2012 to 2018, according to the market research firm IHS's latest Automotive Infotainment Market tracker Report. When the wireless technology has penetrated far and wide the home market in developed countries, it's only logical that cars have become the next frontier for wireless technology suppliers. Given that the automotive product development cycle and the life cycle of cars themselves are much longer than those of mobile handsets, the wireless technologies are gradually moving into cars. Why go wireless? What, then, is driving the conservative carmakers to embrace the wireless (Bluetooth, WiFi included) inside the car? It's the mobile devices people are bringing into their own cars, of course. Sure, USB, Aux, and proprietary connectivity solutions are already inside cars so that people can plug their handheld devices into their cars. But once consumers start looking to send data -- downloaded from the Internet onto their handsets or tablets -- to backseat displays or any other devices inside the car, carmakers are now resorting to Bluetooth (already inside a car) or WiFi for executing such content transfer tasks, said Luca DeAmbroggi, senior analyst for automotive infotainment at IHS. Just to be clear, DeAmbroggi isn't suggesting that wireless technologies are replacing existing in-car wired solutions, such as USBs for infotainment; CAN, FlexRay, or Ethernet for in-car networks; or embedded links used by in-car cameras designed for safety, Advanced Driver Assistance Systems (ADAS), and others. But the overall use of wireless inside a car is picking up, DeAmbroggi said. (Source: IHS, July 2013) In the automotive market, for example, the USB legacy wired connectivity solution is "being challenged by wireless mechanisms in cars such as Bluetooth for exchanging data between fixed and mobile devices over short distances, as well as embedded cellular for two-way wireless telematics connectivity," the analyst explained. Bluetooth in cars, we understand. The question is, which versions of those wireless technologies are being embraced by automotive companies, as the rest of the world is quickly moving onto the next-generations of faster WiFi and lower-power Bluetooth? DeAmbroggi noted that automakers are now looking at Bluetooth 4.0 (based on Bluetooth Low Energy) and 802.11ab, for example. The Bluetooth 4.0 will offer higher transfer speeds with the high-speed (HS) option, while ensuring that gadgets stay paired longer and take up less power, he explained. But of course, neither Bluetooth 4.0 nor 802.11ab is capable of transferring big data -- such as video captured by in-car camera, which needs to be high-resolution with no compression allowed. Further, when consumers want to stream HD video from their smartphone to backseat display, neither wireless technology will cut it. WiGig in cars Panasonic, for one, announced last year an after-market wireless product based on the new WiGig technology, supporting data transmission rates up to 7 Giga bit per second by using 60GHz frequency band. In the demonstration, the Japanese company showed a passenger transferring media from the tablet to a display mounted in the passenger seat. An exchange of content also takes place from the car's computer over to the tablet; the passenger checks out auto information such as readings on tire pressure and battery capacity. While Panasonic's video demo has gotten a lot of attention, DeAmbroggi doesn't believe it has reached the commercial market yet. Wireless conundrum Regardless of different wireless technologies currently under consideration for in-car usages, one thing is for sure: Consumers will always crave for bigger and faster wireless solutions, as long as their own mobile devices are bridged to the Internet and they download more content. Nothing can stop consumers' insatiable appetite. At minimum (without even going to WiGig), though, one way to address the wireless conundrum in cars is to make sure that there will be WiFi in a car so that any overflow of data can be transferred by switching the technology from Bluetooth to WiFi, the IHS analyst said. However, DeAmbroggi said that he isn't sure if automotive OEMs will prefer a decoupled solution for Bluetooth and WiFi in cars, or if they will opt instead for a combo approach that optimizes cost and reduces the design workload. Almost all of the smartphones these days use WiFi/Bluetooth combo chips. Why wouldn't carmakers use them? DeAmbroggi reminded, "First, those combo chips used in mobile devices are not automotive qualified parts." Second, he said, "My concern is the cost issue. Even though the broader diffusion of wireless technologies points to integrated combo solutions being used in the future, a separate chip approach is more likely -- at least in the short term." That's due to the still limited pull of WiFi in automotive, he explained. "The integration of WiFi is still limited to premium cars." Automotive OEMs are weighing the cost, use-case scenarios (for tablets and mobile phones inside a car) and bandwidth requirements, he added. Regardless of the wireless technology to be used in cars, DeAmbroggi cautioned that there are a number of issues and concerns that "must be taken into consideration prior to implementation." They include "signal reception, electromagnetic interference, increasing system complexity because of varying wireless frequency spectrums, and regional differences and specifications," he explained. Such variables, in turn, will affect the cost of the wireless system and components to be included.