The RF calibration process fundamentally consists of 3 parts:

1: The FreeCalypso GSM MS device under test (DUT) to be calibrated;

2: An RF test station to which the DUT is connected via an RF coax cable,
   performing the RF signal analyzer and signal generator functions required
   for the calibration procedures;

3: A program that communicates with both the DUT and the RF test station and
   orchestrates all of the signal generation, measurement and computation steps
   to arrive at the final calibration results to be stored in the flash file
   system of the DUT.  The steps are too numerous, tedious and repetitive to be
   performed manually, hence automation is required in order to make the process
   practical.

The goal of the FreeCalypso RF calibration subproject is to produce a set of
tools for performing part 3 of the above breakdown.  The current vision is that
our automated calibration software will be broken down into two interfacing
components:

1: There will be a Test System Interface Daemon (TSID) that encapsulates the
   magic specific to a particular brand of RF test station, e.g., R&S CMU200.
   The TSID will only talk to the CMU200 or other RF test station, but not to
   the Calypso DUT, and the intent is that the TSID only needs to be started
   once at the beginning of a calibration work shift and then stay running as a
   hundred or more FreeCalypso GSM devices may be calibrated on the production
   line.  The TSID will present a local socket interface (can be changed to
   TCP/IP if operation over a network is required) to which the other component
   below will connect as a client.

2: There will be a set of 3 programs (fc-rfcal-vcxo, fc-rfcal-rxband and
   fc-rfcal-txband) that perform the 3 required calibration groups for each
   individual FreeCalypso device unit on the production line.  The production
   automation script will need to run fc-rfcal-vcxo first, then fc-rfcal-rxband
   for each of the hardware-supported bands (e.g., 900, 1800 and 1900 on
   FCDEV3B-900), then fc-rfcal-txband for each of the same bands.  Each of these
   programs will talk both to the DUT (via rvinterf) and to the RF test system
   (via the TSID), i.e., will need to connect to an already-running rvinterf
   process and to an already-running TSID via local sockets.

The programs in the second group above will contain no knowledge specific to
R&S CMU200 or any other particular brand of RF test station, instead this
knowledge is to be encapsulated in the TSID.  The interface between the TSID
and its clients will be of a command-response nature, and will be defined from
the perspective of the needs of the FreeCalypso calibration process, rather than
from the perspective of the capabilities of the CMU200 - in other words, the
calibration automation program will command the TSID to the effect of "I need
this", and it will be the responsibility of the TSID to figure out how to
perform the required measurement or signal generation on the given type of test
equipment.

The details of the TSID socket interface remain to be defined.