This article describes best practices for optimizing blue dot location accuracy on maps in your Meridian-powered app. It begins with an overview of Beacon placement models and deployment best practices. The next section builds upon these best practices and provides a step-by-step process for creating and effecting a Location Beacon deployment plan.

Overview

Aruba Beacons are the key to making a mobile app location aware.  An app that is not location aware will not know its position on a map and will require the user to specify their starting point when requesting directions to a destination.  This is often known as static wayfinding, as opposed to dynamic wayfinding for an app that is location aware.  By placing Aruba beacons in the environment, the mobile app can use those beacons to accurately show the user's location on a map and assist with turn-by-turn directions to a specified destination.  A location aware app can also share its location with other trusted users.

When developing a Location Beacon deployment plan, the most important factor is the accuracy and responsiveness of the blue dot. The goal of the Location Beacon deployment plan is to help you deploy your Beacons to get the most accurate blue dot accuracy throughout your location.  

Adding a beacon to your map is quite simple.   A beacon can be placed on a map using the Beacons app.  The Beacons app is readily available for download from the Apple Store and is ONLY supported on IOS mobile devices.  There is no support for a Beacons app on the Android platform.  To place a beacon, start by tap-and-hold on the desired location on the map.  This will launch a wizard to walk you though the process of placing the beacon.  After the beacon is placed on the map, you will immediately see a blue dot on the map.

Now let's take a look at how an Aruba beacon affects the accuracy of the blue dot.

In the illustration below, the user is standing at the position marked with an X.  Let's see what happens as beacons are added the the map.

• 0 beacon, no blue dot.  
• 1 beacon, blue dot next to the beacon, but it does not accurately represent the user's position.
• 2 beacons, blue dot between the 2 beacons, but it is still not accurately representing the user's position.
• 3 beacons, trilateration gets the blue dot closer, but still not good enough because the user is outside the perimeter of the beacons.  
• 4 beacons, blue dot marks the user's position on the map.  

In a Meridian-powered app, the blue dot accuracy is highly dependent on the quality of the Beacon placement. Because of this, Beacon placement needs to take into account architectural features, such as walls, floor plan layout, staircases, multi-level floors (such as atriums), and mobile device BLE hardware. Even things like fountains and indoor foliage can distort the Beacon Bluetooth signals that the app relies on to generate an accurate blue dot.Given the incredible variety in architectural layouts, the same Beacon deployment model may not work for every location or even for different spots within a location. The layout of your floor plan will determine the type of deployment you'll need to use. Beacon placement can be generalized into two basic placement models:

• Path Model: Use for straight hallways or corridors where you expect the blue dot to move along a single-axis in a straight line
• Area Model: Use for large open areas with very little physical barriers where you expect the blue dot to move along two-axis

We recommend testing and refining your Beacon placement until the blue dot accuracy meets your expectations.

Path Model

The path model is ideal for areas where we want the blue dot to travel in a straight line.  Deploying beacons for the path model will not be using trilateration to determine the location of the user.  As the blue moves down the hallway or corridor, it's only important to show how far along the hallway it is. 

When placing beacons in a hallway, it is best to place all the beacons on one side of the hallway and placed the same height off the ground.  For best results, if ceiling mounting is possible, place the physical Beacons directly down the center of the hallway on the ceiling. 

Area Model

Unlike the Path Model, the Area Model beacon placement is used to track a user as they move in any direction on a map. With at least three beacons, the mobile can better use trilateration to determine the user's position on the map.  

The larger the open area space, the more Location beacons you'll need to deploy in a grid-like pattern. For best results, Beacons should be placed on the ceiling no more than 10 meters apart and no more than 5 meters above the ground.  This is ideal for open areas where there are no physical barriers or obstacle, such as walls, that will prevent a user from moving in that direction.  In an area model deployment, the ideal is to enable the blue dot to move forward and backwards and side to side.  It is more challenging to deploy in an open area because there are not as many physical properties where you can attach the beacon.  This will require a little more imagination.  

Deployment Considerations

The following factors should be considered when determining the placement of Beacons to ensure the performance required by your deployment.

Beacon Sizing

For a location accuracy of 3-5 meters (approx. 6-15 feet) and latency of 3-5 seconds, make sure that Beacons are placed no more than 10 meters (approx. 30 feet) apart and no more than 5 meters off the ground. Closer Beacon placement provides the best indoor positioning experience by improving accuracy and reducing blue dot jumpiness. To assist with beacon placement on the map, the Beacons app has made provisions to include a 10 meter grid to use as a guide.   Follow these steps to make the 10m grid lines visible:

The best distance between placed Beacons may vary based on factors such as the deployment model, variations in ceiling height, reflective vs. non- reflective environments, etc.

The 10 meter Beacon distance is a guideline and your actual deployment may need to differ. Experimentation with subtle changes to Beacon placement is often necessary before the optimal placement is found.

Beacon Mounting

Battery-powered Beacons are small enough to be mounted in many different places using a variety of techniques and options. It's most common to mount battery-powered Beacons on walls and ceilings. 

There are three mounting options are available for battery-powered Beacons:

• Adhesive on the back of the Beacon 

• Indoor mounting bracket
• Outdoor mounting enclosure 


The mounting brackets not only make replacing Beacons easier, but they're also quicker to install since the brackets come with a single piece of adhesive, versus the 4 small pieces used for a standalone beacon (that is, peeling 1 vs. 4 stickers is faster). You can read more about the mounting options here.

Aruba Part Number	HPE Part Number	Description
LS-BT1-MNT-50	JW145A	Indoor mounting bracket for battery powered Aruba Beacon - pack of 50 brackets
LS-BT1-NEMA	JW144A	Outdoor mounting bracket for battery powered Aruba Beacon and Aruba Tag

The options and techniques used in your deployment will depend on the factors described in the following sections.

Wall Mounting

Wall mounting can be used in open-roof areas or areas with very high ceilings where installation might be a challenge. Wall mounting is easier than ceiling mounting and you can use all three mounting options. Even though though Beacons are small and unobtrusive, they are more visible when mounted on the wall.

Ceiling Mounting

Ceiling mounting is ideal for environments with aesthetic concerns, because it allows Beacons to be installed discreetly and out of line-of-sight. Ceiling mounting also keeps Beacons out of reach from curious people and prevents tampering or theft. Additionally, because crowds of human beings can attenuate the Bluetooth Beacon signals, ceiling mounting provides more resilience to that.

Keep the following in mind when installing ceiling-mounted Beacons:

• Make sure Beacons are mounted away from the heat generated by light bulbs.
• Beacons must be mounted below ceiling tiles, because some types of tiles may impair Beacon signals.
• For environments with different ceiling heights, make sure Beacons are placed on the lower ceiling height to prevent the blocking of Beacon signals from different locations.
• Ceiling mounting may require a personnel lift, mounting stick, or ladder. Take proper safety precautions when climbing to place Beacons.

Reflective Environments

Reflective environments, such as areas with marble floors, may result in an increase in blue dot jumpiness. Carpeted areas have shown better blue dot stability than areas with marble floors. In locations where reflective surfaces are unavoidable, consider using the path model instead of the area model.

Open Multi-Level Environments

"Open multi-level environments" refers to open indoor areas that extend through multiple floors.

Some examples are:

• An open atrium or lobby on the first floor that is open to the floors above.
• A stadium or auditorium with multiple seating levels
.
• A shopping center or large venue with multiple floors that opens into a common area on a different floor.

For open multi-level environments, the user will have a more stable blue dot experience if Beacons are placed low or close to the ground. It’s best to avoid direct line of sight to Beacons on different floors.

Examples of where to place Beacons in this environment are:

• Under seats. This helps to attenuate Beacon signals to reduce the amount of interference with other Beacon signals.
• Below handrails. This localizes Beacon signals.
• Face the front of the Beacon away from the open area. This will reduce Beacon signals going into the open space. The front of the Beacon is the side with the Aruba logo.

In summary, to minimize the signal bleed through open areas, place the Beacons low and direct the front of the Beacon away from the open area.

Create Your Location Deployment Plan

This section describes the steps you'll need to take to create and implement a Location Beacon deployment plan. 

Before you can do this, you'll need at least one map in the Meridian Editor. If you don't have a Meridian map,  please read about how to start that process. You'll also need to  download the iOS Aruba Beacons app. 

The steps are:

1. In the Meridian Editor, add routing to your maps.
2. Identify paths and areas.
3. Deploy Beacons in hallways.
4. Deploy Beacons in open areas.

Step 1. Add Routing to Your Maps

Once you have a Meridian map, you'll start by adding routing to your maps in the Meridian Editor. The routing represents all the possible paths that your users can walk to get from one point to the next. To do this, go to the Meridian Editor, navigate to the specific map, and add the routing for each of your maps.

Here's an example of what some finished routing might look like:

FIGURE 1: Each node in the routing represents a point at which the Meridian-powered app's turn-by-turn directions will give your users a new direction.

Step 2. Identify Paths and Areas

After the routes are created, review the map and identify the hallways (paths) and open spaces (areas).

FIGURE 2: Identify the paths and areas where the blue dot will be displayed.

Before moving on to the next steps, you’ll need to evaluate what's already been deployed in the current environment. In a facility where there are no Aruba access points (AP) deployed, you can start deploying Beacons. (We recommend a Beacon placement density of no more than 10 meters.) 

If Aruba APs with Bluetooth low-energy (BLE) Beacons have already been deployed, you’ll need to take those into consideration so you can use what's already available. If you haven't done so, you’ll need to enable the BLEs in those APs and configure them to beaconing. If the APs are already beaconing, you’ll see the beacon MAC address when using the Beacons app to scan for Beacons.

Here's an example of a location with already deployed access point Beacons (APB).

FIGURE 3: You won't need to deploy battery-powered Beacons in places where there are already existing APBs. 

Step 3.  Deploy Beacons in Hallways

In hallways, the user will be moving in a straight line, so you'll deploy Beacons using the path model.

You can place the physical Beacons either on the ceiling or, if that's not possible, the wall. Because the blue dot will gravitate towards all nearby Beacons, take care not to configure Beacons on the other side of walls along the hallways people will be walking. Using a Beacon that is off the path may result in a blue dot that zigzags while a user is walking or shows the user in an area that is separated by physical obstructions, such as a wall.

Single Level Hallway

In the example below, APBs and battery-powered Beacons are used to complete the path model.

FIGURE 4: An example of how Location Beacons should be deployed along hallways.

If possible, place Beacons on the ceiling. If that's not possible, place Beacons on the same side of the hallway at the same height in a straight line. 

Only use APBs for the placement model if it's appropriate to do so. If there are APBs near the hallway in a room, separated by a wall, don't use it as a location Beacon. Set it to proximity. It can still be used for Beacons Management, but won't degrade the blue dot accuracy.

High Ceiling or Multi-Level Hallway

Not all hallways will be on a single floor or will have obvious locations to place Beacons. In Figure 5, the hallway is open to the floor above, which makes it difficult place Beacons in the middle of the hallway, such as the ceiling. Although the hallway is wide, a path model deployment will work, because what's important is showing where the user is along the hallway.

FIGURE 5: An alternate use case for path model to deliver expected blue dot behavior.

Initially the deployment team placed the Beacons in a staggered pattern down the hall and configured the Beacons to be as close as possible to the actual Beacon placement. This resulted in the blue dot moving from side to side as the user walked down the middle of the hallway. To fix this, the Beacons were taken down and placed along the right side of the hall, but in the Beacons app the Beacons were placed closer to the center of the hallway. This way the blue dot will show the user is in the middle of the hallway instead of being next to a wall.

Step 4.  Deploy Beacons in Open Areas

Use the area placement model in open areas, because your visitors will have more space to move around without a physical barrier, such as a wall, to obstruct their movement.

Single Level Open Area

While the path model employs only two Beacons and tracks movement along one dimension, the area model uses three Beacons to track the user along two dimensions.  Since there are no walls to be concerned with, it's ok to have the blue dot move more freely within the space.

FIGURE 6: Deploy Beacons using the area model.

Remember to configure existing APBs as location Beacons only if the Beacon applies to the use case in the area. If a nearby APB is available but doesn't fit the deployment model, configure it as a proximity instead of a location Beacon. This way the APB can still be used for Beacons Management and does not degrade the blue dot accuracy.

Figure 7 shows the final result after all the Beacons have been deployed to meet the blue dot requirements for both path and area models. Keep in mind: configure Beacons for location if it satisfies the use case, otherwise configure it for proximity so that it can still be used for Beacons Management.

FIGURE 7: The end result after applying Beacon deployment techniques.

Multi-level Open Area

Multi-level open areas are a special case that can be an especially tricky spot to deploy Beacons. Examples include things like open lobby with elevated pathways above or an open stadium field with elevated seating all around.

Multi-floor Open Atrium

One of the most challenging situations is an open area that is open to floors above.

The problem with this layout is floor hopping. Floor hopping is a behavior where, for example, the blue dot will show the user on Level 2, when they're physically on level 1. This happens if the mobile device has a direct line of sight or is able to hear a Beacon from the other floors.

FIGURE 8: Open area that is open to floors above is susceptible to floor hopping.

Use the following techniques to avoid floor hopping in multi-level open areas:

• Place the Beacon with the front facing away from the open area.
• Face the Beacons into the hallway or inner open area.
• Use physical barriers to attenuate Beacon signals.

FIGURE 9: To minimize floor hopping on the main floor, place Beacons facing downwards or under furniture. On upper floors, use physical barriers to attenuate signal and reduce line of sight to the open area.

FIGURE 10: Example of Beacon placements for all levels susceptible to floor hopping.

Specific Architectural Features

This section addresses common issues when dealing with specific architectural features.

Stadiums

Stadiums have been the most challenging venue when it comes to Beacon placement. The factors that have impacted Beacon deployments are:

• wide-open area with direct line of sight to multiple levels.
• limited locations for Beacons placement.
• strict aesthetic requirements.

FIGURE 11: A stadium has wide-open areas with direct line of sight to multiple levels. Minimize Beacon signal bleed through and line of sight to avoid floor hopping.

Even with all these challenges, the same techniques for avoiding floor hopping still apply.

Here are some lessons learned from a deployment at a football stadium.

FIGURE 12: The minimized line of sight caused signal to bleed to the level above resulting in floor hopping.

FIGURE 13: Beacons place in direct line of sight to elevated walkways will cause the blue dot to floor hop.

Stairwells

Beacons aren't usually placed in stairways, but stairwells may be an exception. Stairwells can often be an extension of the map level, but are often cut off by a set of doors. Placing a location Beacon in the stairwell by the door may be useful to reduce the app's map transition time.

For example, a user enters the stairwell on level 1 and climbs the stairs to level 2. As the user approaches the entry way to level 2, the map will load and by the time the user is in the hallway of level 2, the map will be ready for use.

FIGURE 14: Beacons placed in stairwells helps to reduce map transition delays.

Elevators

Don't place location Beacons inside elevators. Each Beacon can only be associated with a single map level.

For example, let’s say the Beacon is placed on the level 1 map and the physical beacon is placed inside the elevator. If the user on level 7 is using turn-by-turn directions to a room on level 5, when the user enters the elevator, the map will transition to level 1 and instruct the user to take the elevator up to level 5, instead of down to level 5.

Location Beacons can only have a one-to-one association with maps; therefore, don't place them in elevators.

Indoor to Outdoor Transitions

In some cases, customers require navigation across a campus that includes navigation outdoors. Meridian addresses this use case by transitioning a user from indoor navigation, using Bluetooth Beacons, to outdoor navigation, using GPS. In both cases, Meridian maps are utilized, and of course, all maps must be in the Meridian Editor. A blue dot is shown on the Meridian map when Beacons are used for location. A green dot is shown when GPS is used for location.

For now, this section will only cover beacon placement techniques to ensure a smooth transition from blue dot to green dot.

Only configure a map to use GPS if GPS is possible, otherwise you won't get a green dot on the map. Third party maps, such as Google Maps, can't be used with Meridian location services.

The same techniques used for indoor to outdoor are the same as those used for multi-level open areas: minimize signal bleed and eliminate line of sight.

FIGURE 15: At the building exits, minimize signal bleed and line of sight to outside by placing the Beacons inside the doorway, facing into the building.