Channelizer Offline Test

Purpose

This test verifies the operation of the test generator and its synchronisation. This is done by generating a tone corresponding to the centre frequency of a given course frequency channel. The DAQ receiver is used to capture the synchronised raw ADC data output. The raw synchronised data is then converted into the frequency domain offline, where power and phase of the data from each antenna is compared with the expected results.

This is repeated for the specified range of channels, by default this is channel 100-108. The software requests the LMC data type “synchronized raw adc data“, and captures this using the DAQ receiver.

NOTE: This test only operates on the first TPM in a station.

NOTE: For data acquisition to function correctly, the network interfaces on the TPM must be working, as well as the link to the LMC destination. The LMC destination must be configured to route traffic to the server running the tests. For all tests the simplest option is for the CSP and LMC destinations to be the same network interface, routing all traffic to the server running the tests.

Methodology

  1. DAQ receiver is configured and initialised with the required UDP port and network interface.

  2. The frequency for the internal tone generator is calculated and applied, based on the channel being considered. A random delay is generated and applied to determine the expected phase.

  3. An LMC snapshot of synchronized raw adc data is requested from the TPM.

  4. An offline channelizer, calculates the power and phase of all frequency channels.

  5. For each antenna, channel and polarisation, the power and phase is evaluated against the expected. Note, the expected phase is calculated against the first antenna.

  6. If the intended channel has the correct power and phase, then the test proceeds to the next channel and starts again.