Two years ago we founded Lighthouse because we believed there was an opportunity to replace manual activity with digital, context aware solutions. Whether the end goal is customer engagement, improved productivity or risk mitigation, businesses need accurate indoor location information. And they need that information to be accessible and cost effective. GPS, Low Energy Bluetooth, Wifi, RFID and, more recently, NFC are all important pieces of the puzzle, but each has its limitations.
So, which technology should your business use? Unfortunately, no single solution is the panacea to all problems. Usually, the right answer is dependent on what you are trying to achieve, your environment and your budget.
In this paper, we will compare the 4 most talked-about location technologies - Low Energy Bluetooth (Beacons), WiFi, RFID/NFC and GPS. This is a complex topic and therefore, it is sometimes hard to draw exact apples-to-apples comparisons. That said, the objective of this paper is to:
- Discuss the major factors and tradeoffs for evaluating indoor location technologies
- Provide basic parameters for the average buyer to begin to narrow down options and focus their search
In a perfect world, we want a universally accessible location system that is highly accurate, secure and cost-effective. We will use these attributes to assess each technology, as defined below.
Accessibility refers to the ability of the technology to be "tapped into" or accessed by a consumer or business. No matter what the technology, determining location always requires some infrastructure: a sender (or transmitter), a receiver and a data service. Some systems require additional antennae or translators for value-add functions (for example, to report precise room positioning, RFID systems will supplement zonal readers with active RFID rack room locators).
The more ubiquitous those senders and receivers, the more accessible the system. For example, GPS is a highly accessible technology because there is a single global standard for transmitters (satellites built by the US government) and nearly all mobile devices can act as receivers.
Range refers to the distance the signal travels. For all of the solutions we will discuss, range can depend on the configuration, power settings and environment. For example, a WiFi or Bluetooth signal will travel much further outdoors without any obstruction than in a multi-room, multi-surface indoor setting. Further, it is possible to turn up the power to project a longer-distance signal. This is often the case with WiFi, since the requirement for power and internet generally means that fewer access points over longer range is generally preferred.
Accuracy refers to the reliability of the signal within a given range, and the tolerance of that signal when accounting for environmental factors. For example, beacons are typically more accurate indoors than WiFi because the portable nature of the beacon transmitters allow for configuration workarounds that account for signal refraction and poor reception zones (source).
Security refers to the ability of data sent over the system to be hacked or accessed by 3rd parties or malicious intruders. Note: we will discuss privacy along with security for the purpose of simplicity and because it tends to invoke similar human responses.
Cost includes the expense of setting up, using and maintaining the systems. While 'cost effectiveness' is often relative to the situation, cheaper is usually better when calculating ROI.
So how do they stack up?
The table below summarizes the performance of each technology against these variables. For comparison purposes, we used a 1-5 scale with every technology starting at a perfect 5 and a point deducted for each major drawback or limitation (if there is a "but…" we remove a point).
Note: we have included signal 'range' in the table but have not assigned it a rating. In some scenarios, a completely ubiquitous range is best, in others, restricting to a specific area is required.
|How it works||Bluetooth low energy beacons send a signal; device detects signal and acts based on data service rules||Satellite radio signals. GPS devices receive the signal and determine location.||Wireless access points detect devices and triangulate distance based on received signal strength||Radio 'tags' transmit stored information (passive or active) to 'readers' which record data and/or perform actions based on reader application software rules||Passive UHF RFID chips (usually built into device or card) transmit data to terminals upon close contact|
|Typical Range||1 - 50 meters||Unlimited*||20 - 50 meters||1cm - 100m||10cm or less|
|Accessibility (network infrastructure required)||4||4||3||2||3|
|Accuracy||4||1||3||5||5near range only|
|Privacy & Security||3||3||2||4||4.5|
|Best for||Indoor tracking; passive notification of contextual information; peer-to-peer messaging||Outdoor tracking and navigation; agriculture and military uses||Existing infrastructure and/ or strong need for WiFi connection and location information accuracy is only required within meters||SKU level tracking of inventory, requirements for centimeter accuracy||One-to-one secure delivery of information between consumer and another entity (payment, ticketing, etc.)|
As you can see, there is no clear winner - it depends on the application of the technology. In many cases, the best solution is a combination of techniques. To select the best option for a given use case, you must consider the influencing factors and variables in more detail. Contained within is a more detailed explanation of each location system against our evaluation criteria.