Transcript torun-software

Toruń 32m antenna
General overview of the control
system and data flow.
OCRA/F-GAMMA/OVRO workshop, Bonn 15 Mar 2011
Data & commands flow

Modules
communicate
using TCP
sockets
 Information is
buffered in
shared memory
segments
 Each data
channel is open
in a separate
thread to avoid
locks
Signal monitor
Signal monitor
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Real-time
Multichannel
Variable time span
Additional info
displayed
– RMS
– Peak-to-peak
– Average value
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Configurable
Calibration
Calibration

Tsys and Tcal
measurements for
each OCRA-p data
channel
– fast, Tcal measurement
optional
– uses ambient
temperature
measurements from
the meteo station
– automatically controls
absorber insertion
– Is very colorful
Pointing and flux
measurements
Pointing and flux
measurements

Much faster
measurements
– Antenna is moving
constantly
– 2 offsets can be
measured in <1min.

Is used to measure
fluxes
– Added option to
control the noise
source
Pointing and flux
measurements

Real-time display
of data points and
fitting result
– AZ / EL path
Pointing and flux
measurements

Real-time display
of data points and
fitting result
– AZ scan
Pointing and flux
measurements

Real-time display
of data points and
fitting result
– EL scan
Flux measurements
Flux measurements

CFJ sample
survey
–
–
–
Real-time
display
Online access to
measurements
(SQL database)
Easy selection of
sources for
observations
Flux measurements

CFJ sample
survey
–
–
–
Real-time
display
Online access to
measurements
(SQL database)
Easy selection of
sources for
observations
Flux measurements

CFJ sample
survey
Logging
Log viewer
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Real-time display of messages stored in SQL database
Log viewer

Messages can be
filtered, depending on:
– origin
– importance

Smaller amounts of
observational data can
be also stored by
applications in the log
table
– pointing
– calibration
Telescope control system

Uses fast AMD/64 CPU
Real-time operating
system (RTLINUX)
 PCI RS232 card for
communication with
- motor drives
- position encoders
- industrial PLC controller
(FESTO)
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Telescope control system
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Real-time part is divided
into modules grouped in
„layers”
 Communication between
modules uses FIFO
queues
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Information exchange
with „normal” Linux
programs is done using
rtlinux FIFO queues
and shared memory
segments
There is TCP server as
well as UDP broadcast
OCRA-p data acquisition
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OCRA-p in a dual-beam receiver @30GHz
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Industrial PC computer: Celeron 1.7GHz/512MB RAM
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PCI A/D converter card
– 125kHz sampling frequency
– 12-bit resolution
– 5 channel acquired
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Beam switching frequency is set to 277Hz
– For each switching state we get 2x2 values from two horns
and two detectors, which allow computation of the
differenced signal
OCRA-f data acquisition
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OCRA-f is basically 4 (or 8 in full configuration) OCRA-p receivers
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Industrial PC computer: 2-core Pentium D 3.4GHz/4GB RAM
PCI A/D card
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– 1.25MHz sampling
– 16 bit resolution
– 11 channels acquired (for 4-pair configuration)
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Beam switching frequency is 277Hz (the same as for OCRA-p),
and 1-second data output consists of 277 x 4 values x 4 horn pairs