when i use the DF,i use the connected mode,but i find that the rssi valuse are so big?what is this reasone?

RE: when i use the DF,i use the connected mode,but i find that the rssi valuse are so big?what is this reasone?

Simonr — Tue, 16 Aug 2022 12:27:27 GMT

It's up to you how you'd like the central device to handle the RSSI and IQ sample data. In the general application it is processed by an AOA algorithm to get an estimate of the angle of where the transmitter is located, and the RSSI to get a rough estimate of how far away the device is. See your latest case for more info.

Best regards,

Simon

RE: when i use the DF,i use the connected mode,but i find that the rssi valuse are so big?what is this reasone?

swz_nordic — Tue, 16 Aug 2022 07:33:04 GMT

ok，thanks you.besides this,if i want to get the values of RSSI and IQ samples from this demo.how can i use the values of them not by serial.

RE: when i use the DF,i use the connected mode,but i find that the rssi valuse are so big?what is this reasone?

Simonr — Tue, 16 Aug 2022 07:23:10 GMT

There is indeed a missing unit in the output. Values provided by BT Host API are straightforward copies from the HCI layer, and the units are given in 0.1dBm.

Best regards,

Simon

RE: when i use the DF,i use the connected mode,but i find that the rssi valuse are so big?what is this reasone?

swz_nordic — Mon, 15 Aug 2022 07:04:42 GMT

yes, i use ncs version for 2.0.2.i get the result as same as yours.i use the sample of DF connected.

here is my output rssi.the RSSI is -650.

[14:52:59.193]收←◆CTE[DE:86:9B:6D:43:F0 (random)]: samples count 82, cte type AOA, slot durations: 1 [us], packet status CRC OK, RSSI -670
IQ sample content : 
sample[0] = I:-3 Q:-10
sample[1] = I:1 Q:9
sample[2] = I:-2 Q:-10
sample[3] = I:1 Q:8
sample[4] = I:-2 Q:-9
sample[5] = I:0 Q:9
sample[6] = I:1 Q:-10
sample[7] = I:-1 Q:8
sample[8] = I:-1 Q:9
sample[9] = I:-1 Q:9
sample[10] = I:-3 Q:8
sample[11] = I:-2 Q:8
sample[12] = I:-4 Q:9
sample[13] = I:-4 Q:8
sample[14] = I:-5 Q:8
sample[15] = I:-6 Q:8
sample[16] = I:-6 Q:7
sample[17] = I:-8 Q:6
sample[18] = I:-6 Q:7
sample[19] = I:-8 Q:6
sample[20] = I:-8 Q:6
sample[21] = I:-8 Q:5
sample[22] = I:-10 Q:3
sample[23] = I:-9 Q:4
sample[24] = I:-9 Q:3
sample[25] = I:-10 Q:2
sample[26] = I:-10 Q:2
sample[27] = I:-10 Q:1
sample[28] = I:-10 Q:1
sample[29] = I:-11 Q:-1
sample[30] = I:-11 Q:-1
sample[31] = I:-10 Q:-3
sample[32] = I:-10 Q:-2
sample[33] = I:-9 Q:-3
sample[34] = I:-10 Q:-3
sample[35] = I:-9 Q:-4
sample[36] = I:-9 Q:-4
sample[37] = 
[14:52:59.299]收←◆I:-8 Q:-5
sample[38] = I:-8 Q:-5
sample[39] = I:-7 Q:-7
sample[40] = I:-8 Q:-6
sample[41] = I:-7 Q:-7
sample[42] = I:-7 Q:-8
sample[43] = I:-7 Q:-8
sample[44] = I:-5 Q:-10
sample[45] = I:-4 Q:-10
sample[46] = I:-4 Q:-9
sample[47] = I:-4 Q:-9
sample[48] = I:-3 Q:-10
sample[49] = I:-2 Q:-10
sample[50] = I:-1 Q:-10
sample[51] = I:-2 Q:-10
sample[52] = I:0 Q:-11
sample[53] = I:1 Q:-10
sample[54] = I:1 Q:-10
sample[55] = I:2 Q:-10
sample[56] = I:3 Q:-10
sample[57] = I:3 Q:-10
sample[58] = I:3 Q:-9
sample[59] = I:5 Q:-9
sample[60] = I:5 Q:-8
sample[61] = I:6 Q:-8
sample[62] = I:5 Q:-8
sample[63] = I:6 Q:-7
sample[64] = I:6 Q:-7
sample[65] = I:8 Q:-5
sample[66] = I:8 Q:-6
sample[67] = I:8 Q:-5
sample[68] = I:9 Q:-4
sample[69] = I:8 Q:-3
sample[70] = I:9 Q:-3
sample[71] = I:9 Q:-2
sample[72] = I:9 Q:-3
sample[73] = I:9 Q:-1
sample[74] = I:9 Q:0
sample[75] = I:9 Q:1
sample[76] = I:9 Q:2
sample[77] = I:10 Q:1
sample[78] = I:9 Q:2
sample[79] = I:9 Q:2
sample[80] = I:8 Q:4
sample[81] = I:8 Q:4

[14:52:59.743]收←◆CTE[DE:86:9B:6D:43:F0 (random)]: samples count 82, cte type AOA, slot durations: 1 [us], packet status CRC OK, RSSI -630
IQ sample content : 
sample[0] = I:-1 Q:-10
sample[1] = I:-2 Q:9
sample[2] = I:2 Q:-10
sample[3] = I:-3 Q:8
sample[4] = I:2 Q:-10
sample[5] = I:-2 Q:9
sample[6] = I:2 Q:-10
sample[7] = I:-3 Q:9
sample[8] = I:-4 Q:9
sample[9] = I:-5 Q:8
sample[10] = I:-5 Q:7
sample[11] = I:-6 Q:8
sample[12] = I:-6 Q:7
sample[13] = I:-7 Q:7
sample[14] = I:-8 Q:6
sample[15] = I:-7 Q:6
sample[16] = I:-8 Q:6
sample[17] = I:-9 Q:5
sample[18] = I:-9 Q:4
sample[19] = I:-8 Q:4
sample[20] = I:-10 Q:3
sample[21] = I:-10 Q:2
sam
[14:52:59.819]收←◆ple[22] = I:-9 Q:1
sample[23] = I:-10 Q:1
sample[24] = I:-10 Q:0
sample[25] = I:-10 Q:0
sample[26] = I:-10 Q:-1
sample[27] = I:-10 Q:-2
sample[28] = I:-9 Q:-2
sample[29] = I:-9 Q:-3
sample[30] = I:-9 Q:-3
sample[31] = I:-9 Q:-5
sample[32] = I:-9 Q:-5
sample[33] = I:-8 Q:-6
sample[34] = I:-8 Q:-6
sample[35] = I:-7 Q:-7
sample[36] = I:-7 Q:-7
sample[37] = I:-7 Q:-8
sample[38] = I:-7 Q:-8
sample[39] = I:-6 Q:-8
sample[40] = I:-6 Q:-9
sample[41] = I:-5 Q:-9
sample[42] = I:-4 Q:-9
sample[43] = I:-4 Q:-9
sample[44] = I:-3 Q:-9
sample[45] = I:-2 Q:-10
sample[46] = I:-2 Q:-10
sample[47] = I:-1 Q:-10
sample[48] = I:0 Q:-10
sample[49] = I:0 Q:-9
sample[50] = I:2 Q:-10
sample[51] = I:2 Q:-11
sample[52] = I:2 Q:-10
sample[53] = I:4 Q:-9
sample[54] = I:3 Q:-10
sample[55] = I:3 Q:-9
sample[56] = I:5 Q:-8
sample[57] = I:6 Q:-8
sample[58] = I:6 Q:-8
sample[59] = I:7 Q:-8
sample[60] = I:7 Q:-7
sample[61] = I:7 Q:-6
sample[62] = I:8 Q:-6
sample[63] = I:8 Q:-5
sample[64] = I:8 Q:-5
sample[65] = I:8 Q:-4
sample[66] = I:9 Q:-3
sampl
[14:52:59.908]收←◆e[67] = I:8 Q:-3
sample[68] = I:9 Q:-3
sample[69] = I:9 Q:-1
sample[70] = I:9 Q:-1
sample[71] = I:9 Q:0
sample[72] = I:9 Q:0
sample[73] = I:9 Q:1
sample[74] = I:9 Q:1
sample[75] = I:9 Q:2
sample[76] = I:8 Q:3
sample[77] = I:8 Q:4
sample[78] = I:8 Q:3
sample[79] = I:8 Q:5
sample[80] = I:7 Q:6
sample[81] = I:7 Q:5

[14:53:00.294]收←◆CTE[
[14:53:00.314]收←◆DE:86:9B:6D:43:F0 (random)]: samples count 82, cte type AOA, slot durations: 1 [us], packet status CRC OK, RSSI -650
IQ sample content :

RE: when i use the DF,i use the connected mode,but i find that the rssi valuse are so big?what is this reasone?

Simonr — Mon, 15 Aug 2022 05:42:06 GMT

We've been able to reproduce this on our end as well, and the theory as of now is that there's a comma missing. So if the RSSI equals 660 for example, the RSSI is actually -66.0.

We're looking into it to confirm this, and I'll get back to you when I hear back from the devs with a clear answer.

Best regards,

Simon

RE: when i use the DF,i use the connected mode,but i find that the rssi valuse are so big?what is this reasone?

swz_nordic — Fri, 12 Aug 2022 08:45:22 GMT

yes，i use the NCS version 1.9.1,the projecr is direction_finding_central.i don't have the NCS latest.

RE: when i use the DF,i use the connected mode,but i find that the rssi valuse are so big?what is this reasone?

Simonr — Fri, 12 Aug 2022 08:38:22 GMT

What version of the nRF Connect SDK (NCS), and what Direction Finding projects are you running here? There was an issue with too large RSSI values (that I think was fixed for NCS v1.9.1), so if you're using an older version, please try with a newer NCS version and see if that helps. If not I need more information on how your application(s) are set up.

Best regards,

Simon