FreeCalypso > hg > fc-rfcal-tools

annotate doc/Cable-config-howto @ 100:7ad5836d3b87

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
fc-rfcal-vcxo: added check for final freq offset being within 70 Hz
author Mychaela Falconia <falcon@freecalypso.org>
date Fri, 11 Aug 2017 02:45:10 +0000
parents b68301b38ff2
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
95
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
1 One of the critical requirements for proper calibration of Tx power levels (and
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
2 of the Rx "magic gain" to a lesser degree) is that the insertion loss of the
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
3 cabling setup between your CMU200 and your DUTs (Calypso GSM devices to be
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
4 calibrated) needs to be precisely known and accounted for. Actually measuring
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
5 the insertion loss of your cables at the center frequency of each GSM uplink and
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
6 downlink frequency band with 0.1 dB accuracy is your responsibility; the rest
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
7 of this article will merely tell you how to feed these cable loss numbers to
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
8 FreeCalypso RF calibration tools.
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
9
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
10 In our architecture the software component that takes care of adjusting the
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
11 power levels for the cable loss is fc-cmu200d; our fc-cmu200d reads the cable
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
12 loss numbers from a configuration file and instructs the CMU200 itself to
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
13 perform the actual adjustments. Furthermore, our architecture allows for
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
14 multiple cable configurations. Some Calypso GSM devices have SMA RF connectors
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
15 for attaching the antenna, in which case the calibration coax needs to terminate
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
16 in an SMA, others have MS-147 or Murata SWD/SWF RF test ports, in which case the
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
17 calibration coax needs to terminate in an MS-147 or Murata probe connector. If
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
18 you are working with different types of Calypso GSM devices, you will need to
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
19 switch between the corresponding cable setups, as the cable loss numbers will be
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
20 different for each setup: even if you keep the same "main" coax going from your
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
21 CMU200 to an SMA and add/remove Murata's SMA-to-SWD/SWF adapter at the end, the
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
22 addition or removal of that extra adapter will change the total insertion loss
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
23 along the full path, and this change needs to be accounted for.
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
24
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
25 Cable configuration files are kept in the /opt/freecalypso/rfcal/cableconf
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
26 directory; it is up to you how you name your cable configs, but the following
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
27 convention is suggested:
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
28
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
29 * If you have a cable setup that terminates in an SMA connector for calibrating
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
30 Calypso GSM devices with SMA antenna interfaces, the corresponding cable
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
31 config file should be named "sma".
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
32
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
33 * If you have a cable setup that terminates in an MS-147 probe connector for
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
34 recalibrating Mot C1xx phones or similar, the corresponding cable config file
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
35 should be named "ms147".
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
36
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
37 * If you have a cable setup that terminates in a Murata SWD/SWF probe for
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
38 working with devices like Openmoko GTA0x, the corresponding cable config file
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
39 should be named "murata".
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
40
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
41 See cableconf-example for an example of the syntax, but please remember that
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
42 you are still responsible for putting in YOUR OWN numbers for the actual
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
43 insertion loss of your cable setups.
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
44
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
45 When you actually run fc-cmu200d to begin a calibration session (see the
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
46 General-flow article), you will select the cable configuration to be used
b68301b38ff2 doc: Cable-config-howto and General-flow written
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
47 by name with the -c option to fc-cmu200d.