Wi-Fi Location


位置与移动性密不可分。无论在室内还是室外,消费者都想知道他们在哪里,周围有哪些东西。Wi-Fi CERTIFIED Location™在室内提供达到米级的准确度。凭借Wi-Fi连接的优势,无需单独的定位基础设施或费用高昂的维护,支持Wi-Fi Location的网络和设备就可联手提供准确的定位信息。

支持Wi-Fi Location的设备帮助网络管理员、操作系统开发人员和应用开发人员提供先进的、以定位数据为主导的应用和服务。Wi-Fi Location认证确保基于标准的设备互操作性,以便开发人员能够为用户提供与室外相同的室内体验。


Wi-Fi Location允许自我定位的接入点建立准确的室内位置,并使6GHz标准功率的应用可用。通过使用FTM范围请求和报告,客户设备可以在不分享任何信息的情况下确定其相对于传播接入点的位置,从而在不损害隐私的情况下提供极大的准确性。Wi-Fi Location不仅提高了导航定位数据的准确度,还为开发新的、功能丰富的应用和服务创造了条件。Wi-Fi 无处不在,无需额外设备即可轻松利用现有网络基础设施来实现准确的室内定位。Wi-Fi Location可以通过以下应用和服务,造福工业、企业、零售和医疗保健市场:

  • 室内导航:Wi-Fi Location精确到一米以内,并提供每秒数次的更新;
  • 资产管理:跟踪高价值移动设备;
  • 网络管理:准确定位哪里需要排故和维护;
  • 地理围栏:建立虚拟边界,当设备进出边界时,触发行动;
  • 自我定位的接入点:Wi-Fi Location允许自我定位的接入点建立准确的室内位置,并使6GHZ标准功率的应用可用。
  • 紧急服务:Wi-Fi Location能够运用公民地址及楼层号码进行定位,有可能帮助缩减应急服务响应时间。

Frequently Asked Questions

Does Wi-Fi Location coexist better with a Wi-Fi data service and ensure quality of service compared to other localization technologies?

A localization service is part of a larger connectivity service. By using the Wi-Fi network to provide location services, native co-existence is achieved between the location and core data connectivity service. This kind of native support results in an ability to maintain the QoS of the data service, while ensuring the performance and accuracy of the location service.

How do environmental factors affect Location accuracy?

The environment can play a role, and introduce multipath, which may cause the range to be overestimated. This includes building materials, the presence of RF reflectors such as HVAC metal ducting, and some eco-glass designed to reflect the sun’s rays, but also reflects RF. Often these effects are transitory for a mobile device, and a typical motion filter will remove them from the estimated path.

How does the Wi-Fi channel bandwidth affect location precision?

Location precision is inversely proportional to bandwidth. If an 80 MHz channel bandwidth results in a location precision of 1 meter, then for a 160 MHz bandwidth channel, the precision will be roughly 0.5 meters.

At what rate can Wi-Fi Locations be estimated to support indoor navigation?

This depends on the implementation, but there are commercial examples of devices that can range to 6 access points at 2-3 Hz. When combined with digital maps, this results in a smooth turn-by-turn navigation experience. The ranging rate when multiple devices are positioning at the same time will also affect network utilization and needs to be considered when a network deployment is being planned.

What are the network infrastructure benefits of accurate Wi-Fi Location?

For the Wi-Fi infrastructure venue owner, Wi-Fi Location provides a valuable additional user-facing location service (see "What are the primary uses of Wi-Fi Location?” for examples), with no additional operational cost, and may even save running costs by helping the owner maintain their network, locating access points after site remodels.

What are the mobile client benefits of accurate Wi-Fi Location?

Wi-Fi Location enables a mobile client to determine its location to an accuracy of about 1 meter (at 80 MHz bandwidth), when operating within a Wi-Fi network. There is no additional hardware cost, or any significant impact on battery lifetime.

What is the value of Wi-Fi CERTIFIED Location?

Wi-Fi CERTIFIED Location ensures a Wi-Fi product conforms to the IEEE standard with respect to the FTM protocol and can operate within the accuracy expected for range estimation. Positioning and applications, such as indoor navigation, can be supported when all participating devices have certification.          

What is the difference between ranging and location?

Wi-Fi ranging estimates the distance between two devices using the FTM protocol. When three or more ranges to nearby access points at known positions are combined, the mobile device can estimate its own location (or position) on a map.

What are the primary uses of Wi-Fi Location?

Wi-Fi Location can be used where GPS cannot. A typical location-based application is positioning and route finding inside a building (aka indoor navigation), allowing users to be directed to a specific place, thing, or product. It also enables proximity applications, which include wireless keys/locks, smart home control (actions triggered by relative positions of devices), and access-control to digital resources based on location.

What is the difference between Wi-Fi Aware and Wi-Fi Location?

Wi-Fi CERTIFIED Location™ is used for determining device location within a network by finding and connecting to access points, whereas Wi-Fi Aware is about connecting directly to other devices to publish and advertise information and services without an access point. Wi-Fi Location™ and Wi-Fi Aware can be utilized for similar uses, such as geo-fencing or personalized shopping, but Wi-Fi Location is meant to operate within Wi-Fi infrastructure to deliver precise location determination. Wi-Fi Aware is focused on connecting devices within an area of proximity without a network infrastructure.

How does Wi-Fi Location determine a mobile client device’s location?

Wi-Fi Location uses the time-of-flight (ToF) of IEEE 802.11 frames to locate a device within a network (also called round-trip-time (RTT)). It is based on the Fine Timing Measurement (FTM) protocol, enabling a mobile device to estimate its distance relative to one or more fixed position Wi‑Fi access points (APs) in the network. The mobile device can then combine these measurements, and locate itself on a floorplan, map or in latitude and longitude coordinates.

Does my client device need to be associated with an access point on a network to determine location?

No, using Wi-Fi Location, a client device can negotiate with an access point (AP) to determine its location even when the client device is not associated with that AP.

Must both client and network devices be Wi-Fi Location enabled for Wi-Fi Location to work?

Yes, both client and network infrastructure devices must be Wi-Fi Location enabled to support positioning.

How many infrastructure devices are needed to accurately determine a device’s location?

To determine its location on a map, a mobile client device must use a minimum of three distance measurements to nearby access points at known positions, a process called trilateration. However, more distance measurements to additional access points improves location accuracy, and typically avoids inaccuracies introduced by poor access point layout.

Is Wi-Fi Location power efficient?

Yes. Wi-Fi Location minimizes its impact on client battery life by allowing a device to negotiate the scheduling, and operational parameters, for a Fine Timing Measurement (FTM) protocol exchange. A single RF distance measurement can be completed in as little as 0.5 milliseconds.

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