annotate pirelli/rssi @ 393:6c31d8c54ae4

se_k200i: preliminary analysis
author Mychaela Falconia <falcon@freecalypso.org>
date Sun, 06 Nov 2022 01:13:43 +0000
parents a7707c174510
children
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a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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1 I have been wondering for a long time now how the RSSI bars displayed in end
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
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2 user phone UIs correspond to actual Rx signal levels; Pirelli's RSSI icon on
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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3 the left side of the home screen can go up to 6 bars, but it was not clear at
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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4 all what these bars actually correspond to. I just did an experiment to shed
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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5 some light on this issue: I took a decased Pirelli motherboard and connected it
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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6 to our CMU200 instrument via the RF test port which Pirelli's mobo has like
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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7 most phones. Pirelli's RF test port is of the Murata SWD/SWF type, same as
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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8 Openmoko GTA0x and Motorola C139, and we have a test probe for these ports with
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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9 precisely known insertion loss numbers, thus combined with the properly
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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10 calibrated CMU200 instrument and our "main" SMA cable for which we also have
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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11 precisely known insertion loss numbers (it is the setup we use to calibrate our
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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12 FCDEV3B modem boards), it is a very trustworthy setup. I varied the downlink
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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13 signal level put out by the CMU200 and observed the bars displayed by Pirelli's
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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14 fw on the home screen, and this is what I got:
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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15
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
16 transition from 5 to 6 bars at -75 dBm
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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17 transition from 6 to 5 bars at -80 dBm
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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18
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
19 transition from 4 to 5 bars at -85 dBm
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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20 transition from 5 to 4 bars at -90 dBm
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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21
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
22 transition from 3 to 4 bars at -92 dBm
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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23 transition from 4 to 3 bars at -97 dBm
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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24
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
25 transition from 2 to 3 bars at -97 dBm
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
26 transition from 3 to 2 bars at -102 dBm
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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27
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
28 transition from 1 to 2 bars at -104 dBm
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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29 transition from 2 to 1 bars at -105 dBm
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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30
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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31 at -110 dBm it is marginal: sometimes 1 bar, sometimes 0 bars, sometimes no srvc
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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32
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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33 Looking at TI's reference firmware which Pirelli's fw must be based on, the Rx
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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34 signal strength is passed from L1 to the G23M PS in the form of RxLev numbers
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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35 that go into GSM 05.08 measurement reports (the standard [0,63] range with 0
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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36 corresponding to -110 dBm), ALR does no transformation, and RR passes these
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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37 RxLev numbers to the Rx driver in the Condat drivers layer, which then converts
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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38 them to the "bars" numbers for the UI. Pirelli's fw most likely retains this
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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39 architecture, and their modified version of the Rx driver appears to have the
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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40 following thresholds or somewhere around there:
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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41
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
42 RxLev >= 35: 6 bars
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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43 RxLev >= 25: 5 bars
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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44 RxLev >= 15: 4 bars
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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45 RxLev >= 10: 3 bars
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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46 RxLev >= 5 or maybe 6: 2 bars
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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47 RxLev abysmally low: 1 bar
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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48
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
49 The 5 dB hysteresis seen in my CMU200 experiment is probably caused by the
a7707c174510 pirelli/{rssi,txcal}: results of the Pirelli to CMU200 experiment
Mychaela Falconia <falcon@freecalypso.org>
parents:
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50 RSSI_MIN_DIFFERENCE logic seen in rr_csf.c in our TCS3-sourced version.