What will the range be with a ble 5 server, but iphone with Bluetooth 4

RE: What will the range be with a ble 5 server, but iphone with Bluetooth 4

RK — Sun, 23 Apr 2017 02:37:17 GMT

If you're fighting range issues consider equipping the non-mobile piece with a proper antenna. The original nordic nrf51 dev boards used to ship with a small whip antenna and the range extension you get with that was dramatic. Doesn't help if both bits need to be mobile of course.

RE: What will the range be with a ble 5 server, but iphone with Bluetooth 4

endnode — Sun, 23 Apr 2017 01:37:06 GMT

(all that assuming that it's not your mobile app who kills the connection because it's impatient and few lost packets scare it too much...)

RE: What will the range be with a ble 5 server, but iphone with Bluetooth 4

endnode — Sun, 23 Apr 2017 01:34:40 GMT

Yes, if you are at the edge of Rx sensitivity (= "weak signal") then some packets get lost and because BLE has 100% link layer reliability these packets will be re-transmitted until they go through or link is terminated. Now termination can be caused by two factors: either higer-level application will ask for it because it stops getting data and decides that link is lost or by relying on Link Layer low-level time-out which has value typically agreed during connection (aka "Supervision Timeout"). Note that Supervision Timeout used by phones is very much device type/vendor specific a vary widely (Android devices using values from 1 to 20s) but iPhones specifically are using very short value of 0.5~1s. So if you would be on Android you might get less terminations of the link because of temporarily week signal (but long retry cycles) while with iOS devices you might be out of luck.

RE: What will the range be with a ble 5 server, but iphone with Bluetooth 4

Renix — Sun, 23 Apr 2017 01:21:10 GMT

Good news.

I changed the TX power from (-8) to (+4), and now I can be inside the house, and BLE board in the far corner of the yard, and it stays connected.

I noticed that If I move out of range, and lose connection, then move slightly closer and reconnect, the Services take longer to be displayed on the iPhone.

I assume the weaker signal will cause more packet loss, so more retransmissions?

Regards

RE: What will the range be with a ble 5 server, but iphone with Bluetooth 4

Renix — Sun, 23 Apr 2017 00:47:14 GMT

endnode,

Thanks. I forgot about adjusting TX Power. I will try that next. I remember reading about it, so will try and see where and how to do that.

Regards

RE: What will the range be with a ble 5 server, but iphone with Bluetooth 4

endnode — Sun, 23 Apr 2017 00:23:03 GMT

Btw. if you have two nRF5x boards (whatever variant and PCB type) I would suggest to set-up DTM test examples (as per nRF5 SDK) and run it on max Tx power (+4dBm). If you place devices to desired distance you could get from results (PER) some feeling where are real limits of the chip, if it has rather Tx issues or Rx. Of course iPhone will be always black-box in your game but still you have one side to optimize so I would try to find out if it's possible.

RE: What will the range be with a ble 5 server, but iphone with Bluetooth 4

endnode — Sun, 23 Apr 2017 00:18:04 GMT

I see (and share your disappointment, working on similar topology where I expect to be able to cover a "average" house with BLE without such issues). Have you tried to play with Tx Power on nRF5x side? Can you debug it on nRF5x side and confirm what are RSSI values seen when iPhone approaches the edge of reliable zone? Can you run some sniffer at close proximity of the phone and see if it sees just half of connection events from certain moment (suggesting Tx power/antenna performance/Rx sensitivity issues on either side)? I'm afraid that the only advantage of switching to BR/EDR would be higher transmit power allowed (if I'm not mistaken) but who would like to learn completely different network stack, chip, APIs...

RE: What will the range be with a ble 5 server, but iphone with Bluetooth 4

Renix — Sun, 23 Apr 2017 00:08:48 GMT

Hi endnode, I just need to get from inside the house to anywhere in the backyard.

Now, I lose the connection as soon as I walk in the backdoor.

Perhaps BT classic would be the way to go, but I have invested so much effort into BLE so far.

It will be really painful to go through this again switching to BR/EDR

Regards

RE: What will the range be with a ble 5 server, but iphone with Bluetooth 4

endnode — Sat, 22 Apr 2017 23:34:08 GMT

Yes, SGS8 should be BT5.0, but the "long range" support is all just fabricated by journalists who see "BT5.0" on the box and "BT 5.0 brings high speed and long range" headlines few months back so they think they understand it, 1+1=3 and hooray, let's write it on the internet. At least this is what I read from Verge article and others. But of course I might be terribly wrong.

RE: What will the range be with a ble 5 server, but iphone with Bluetooth 4

Daniel Wang — Sat, 22 Apr 2017 23:33:08 GMT

What kind of distance/range do you need?

RE: What will the range be with a ble 5 server, but iphone with Bluetooth 4

Daniel Wang — Sat, 22 Apr 2017 23:32:33 GMT

If I used a nrf52840 bluetooth5 as a server, but customers have iPhones with Bluetooth 4.x on, will the range still be 2x or 4x, as stated by BT SIG?

No, to use the BLE 5 Long Range feature both Peripheral and Central need to support the BLE 5 Long Range featue.

RE: What will the range be with a ble 5 server, but iphone with Bluetooth 4

Daniel Wang — Sat, 22 Apr 2017 23:23:58 GMT

Well, Samsung Galaxy S8 will be the first phone that support Bluetooth 5.0. According to several tech-magazines and websites it will support the Long Range feature, but I haven't seen any thing official from Samsung on this yet.

RE: What will the range be with a ble 5 server, but iphone with Bluetooth 4

endnode — Sat, 22 Apr 2017 22:16:48 GMT

Hi,

I guess no phone today supports BT 5.x "Long Range" data rates (500/125kbps), certainly not iPhones currently in the field. To be honest this BT 5 feature doesn't look like anything desperately needed on the phones (= you want to create local connection with your gadgets, car etc., certainly not to communicate on hundreds or thousands of meters) so it wouldn't be surprising if there would be no phones/tablets at all equipped with this feature in the future (remember that many features in BT SIG specifications are optional so you don't need to support everything to have sticker "compliant with BT5"). If you have issues with the range I'm afraid BT5 won't help you (nor today neither any time soon), only better antenna tuning, chip sensitivity or totally changing architecture (e.g. is BLE really right solution?).