Setting the GAZZELL Transmission power to 500 meters using BT832X module

[Aditya Narayan Tripathi]

I am using Fansttel BT832X SoC with SDK 14.2 ( Soft Device Version S132 5.0 ). i have configured PA/LNA mode in  BT832X module. If i use only BLE advertisement i can see the  device name upto 200 meters. i wanted to transmit the data using GAZZELL protocol upto 100m range. i am using the same procedure as i used in BLE advertisement. The BT832X module is unable to transmit the data upto 100m range using the GAZZELLE protocol, but i am able to see the advertisement in nrfconnect android mobile app more than that range. i have two questions :

1- Can we increase the GAZZELL transmission range upto 500 meters using Fansttel BT832X SoC.??? 
     if yes, than please suggest me the alternative way to transmit the data upto 100 meters using GAZZELL protocol with Fansttel BT832X SoC. 

2- is the Fansttel BT832X SoC module  having  support to communicate with two same device each of them having BT832X using GAP/GATT???
     Does it have support for GAZZELL also with a range of 500 meters???

[Kenneth]

Hi,

There is a slight difference in modulation between Gazell and BLE, which means that BLE have about 3dB better sensitivity for the same datarate. So likely this is why you are seeing a reduction in range. The range will depend on antenna design (for instance a directional antenna give better range), output power (adding a PA will increase range), and data rate (typically lower data rate give better sensitivity). Range is also influenced by obstacles and interference sources.

Best regards,
Kenneth

[Aditya Narayan Tripathi]

Hi Kenneth,
                  Thanks for your response. 

We are currently developing a wireless system based on a nRF52832 (using Laird BL652 modules). Our requirements prevents us from using BLE (way too much latency), thus we used Nordic's Gazell implementation (nRF5 SDK 14.2.0) and it worked quite well for us.

However, we need to increase the range of our system, thus we tried to replace our Laird BL652 modules with a Fanstel BT832X, which features a nRF52832 as well as a Skyworks SKY66112-11 PA/LNA module.

As we couldn't see any PA/LNA support in the Nordic Gazell Link Layer implementation and couldn't add it ourselves due to the lack of source code, we switched to Nordic's ESB implementation, which we could modify to control the CTX and CRX pins with correct timing (inspired from the documentation of the S132 PA/LNA control API), mostly using PPIs and GPIOTE. However, even after several different implementations we couldn't manage to get it working correctly (much poorer range than the module without PA/LNA, and missed packets). In comparison, the same implementation (without activating PA/LNA control) works flawlessly on our BL652 modules.

I could provide further detail on our implementation, but I'd like to first know whether there is any guideline or code example for implementing PA/LNA support with Nordic's proprietary protocols.

[Kenneth]

The test code for PA/LNA setup is available in the gzll_ack_payload/device example (SDKv15). By default, this example operates in normal mode (without PA/LNA module), but you can set the GZLL_PA_LNA_CONTROL define to any non-zero value to use the frontend module. This has been tested with SKY66112.

Best regards,
Kenneth

[Aditya Narayan Tripathi]

Hi Kenneth, i have tested the example code for PA/LNA setup from the directory:

nRF5_SDK_15.0.0_a53641a\examples\proprietary_rf\gzll\gzll_ack_payload\device\pca10040\blank\arm5_no_packs. After setting GZLL_PA_LNA_CONTROL to 1 also as shown below:

//==========================================================
// <e> GZLL_PA_LNA_CONTROL - Turns on external PA/LNA control.
//==========================================================
#ifndef GZLL_PA_LNA_CONTROL
#define GZLL_PA_LNA_CONTROL 1
#endif

it's operating into Normal mode. After enabling the GZLL_PA_LNA_CONTROL range is still near about to 30 meters same as BL652 module. i am not able to achieve the maximum range according to datasheet of BT832X module.

[Kenneth]

Have you tried using nRF52-DK as reference?

[Aditya Narayan Tripathi]

i have tried separately on nRF52-DK also but getting the normal range.

[Kenneth]

I will check with the team if they provide a picture of the setup they have as a reference.

Best regards,
Kenneth