synchronously recieving RSSI`

[ali zaidi]

I want to make a indoor positioning system using bluetooth 4.0. so for this HOST should recieve the RSSI from the devices it is connected to(from RSSI to distance conversion formulae ,i will get distance of devices from the HOST). i have tried to get the rssi from the devices and acheived by using RF pipe addressing . each device communicate on different pipe with the host and send its RSSI ;now the problem is that only one device is communicating with host at one time , so the correct coordinate of the position i will recieve after all the device send their RSSi to the host(i.e Host takes a time to communicate with all devices and then get the RSSi from all the devices and convert it to the distances). So for this purpose i want to synchronize all devices communication with the host.. please help me.

also help me in synchronous device mode as explained in this link

[Petter Myhre]

Questions on Nordic Developer Zone are public, not just Håkon can see this.

With only one radio, you can only receive one packet at the time.

We will not develop the firmware for you, but we will help you if you are stuck and have specific questions. Then it is helpful if you include details about what you have tried and exactly what you are trying to achieve.

My answer to the edited question:

It is my understanding that you want to find the position of the central device, and have several peripherals in the surroundings of the central. The central is connected to peripherals, and uses their RSSI's to determine its position.

First of all, I don't see why you need to be connected to the peripherals. To me, it seems better to have broadcasters (beacons). The observer can still obtain their RSSI. The minimum advertising interval of a broadcaster is 100ms, which means it sends 10 advertising packets every second. Hopefully this is enough for the observer to calculate an accurate enough position. This you would have to test.

I guess you would like to minimize the time it takes to get the RSSI and convert it to distance, but I don't have an optimized algorithm, you would just have to try and test.

The observer would also need to know the positioning of the broadcasters. This should be included in the software (smart phone app) controlling the observer. The position should be tied to the ID of each broadcaster. Then the observer can get the ID and the RSSI and triangulate to figure out the position.

For future questions, please try to follow this guideline, and also remember that not all questions are suitable for Nordic Developer Zone. We will also help you on the MyPage support portal.

[ali zaidi]

i want to make a indoor positioning system using bluetooth 4.0. so for this HOST should recieve the RSSI from the devices it is connected to(from RSSI to distance conversion formulae ,i will get distance of devices from the HOST). i have tried to get the rssi from the devices and acheived by using RF pipe addressing . each device communicate on different pipe with the host and send its RSSI ;now the problem is that only one device is communicating with host at one time , so the correct coordinate of the position i will recieve after all the device send their RSSi to the host(i.e Host takes a time to communicate with all devices and then get the RSSi from all the devices and convert it to the distances). So for this purpose i want to synchronize all devices communication with the host.. please help me