Mesh of Proximity

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Anonymous
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Hi All,

I am looking to create a mesh of devices which when in range of each other can know proximity (RSSI or can be something else--I believe there is a Proximity BLE service but not sure how it differs from RSSI). This would be a mesh of BCM20736S based devices. Could someone point me in the correct direction on how to do this?

Thank You,

George

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There are 2 concepts in LE, Advertisements and Scan (device can do both at the same time).  The device that scans receives the ID (Bluetooth device address), RSSI and up to 31 bytes of information that advertiser decided to stick in to the advertisement packets.  For example device which sends advertisements can advertise its location (see Location and Navigation sample).  There is a bit of a complication with the ID because for security device can change its Bluetooth device address every so often so that not everybody but only bonded devices can track.

This is what is available today.  In the future version of BT if scanner/observer or advertiser/broadcaster has several antennas they can figure out the direction (angle or arrival, angle of departure), but this is not yet available.

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MichaelF_56
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I believe the Proximity and Proximity_Client applications support RSSI

There are several threads on the site already which discuss the resolution of RSSI using our included profiles.

Here's one them that I normally refer users to: How to find RSSI from WICED SMART?

Note that we also have a Find Me/Proximity application available on the iOS and Android App stores.

Broadcast Mesh will be supported within SDK 2.2 on the 20737 only. I believe the plan is to provide an example within the SDK.

victorz j.t

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Anonymous
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Hi,

  Could you elaborate bit more about 'broadcast mesh'?

  Will it be a persistent connection between each 20737 or a methodology of sending advertising for connection when data is needed to be forwarded?

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If I'm not mistaken, this model uses connectionless broadcasts to relay information through the mesh.  We will learn more when the feature is introduced later this year.

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Anonymous
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mwf_mmfae

mwf_mmfae wrote:

If I'm not mistaken, this model uses connectionless broadcasts to relay information through the mesh.  We will learn more when the feature is introduced later this year.

Will this still be happening?

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Caleb Osterman 


As it turns out, our initial broadcast Mesh offering for the mass market will more than likely be introduced on the SmartReady platform, not the existing 2073XS. We will update the forum as this work progresses.


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Anonymous
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Can you point me to the example you mention here in 2.2?

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hello_client sample in 2.2 sdk performs scan and advertisements at the same time.

Anonymous
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I have 12 BLE devices in a room. Two of them are not in my control--for instance, other products like a Misfit Shine, Apple TV, etc which are BLE server devices.

The 10 devices that I control, I control the firmware on. I want each of them to ID the other 9 devices and tell the proximity of those 9 devices.

Since they are both client (getting the proximity of the other 9 devices and ID) and servers (broadcasting their ID).

That considered, what will the proximity examples give? All of that? Or a subset of the functionality described above?

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There are 2 concepts in LE, Advertisements and Scan (device can do both at the same time).  The device that scans receives the ID (Bluetooth device address), RSSI and up to 31 bytes of information that advertiser decided to stick in to the advertisement packets.  For example device which sends advertisements can advertise its location (see Location and Navigation sample).  There is a bit of a complication with the ID because for security device can change its Bluetooth device address every so often so that not everybody but only bonded devices can track.

This is what is available today.  In the future version of BT if scanner/observer or advertiser/broadcaster has several antennas they can figure out the direction (angle or arrival, angle of departure), but this is not yet available.

Anonymous
Not applicable

A better question might be:

If I want to advertise and scan (not at the same time) can I do that with BCM20736S? Which examples could show me how to use the BCM20736S in scanning mode?

Thank You,

George

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application can indeed start scanning and advertising at the same time.  stack will know when to open the receiver to scan and when to send the next advertisement packet.  see hello_client sample.