For observing cosmological signals at red-shifted hydrogen 21 cm line between 980 MHz and ~1300 MHz, this customer requested Digitizers with an improved resolution and a real time FFT. The measurement had to be performed only at defined hours, in order to be synchronized with the antennas focus on defined astral objects. As the measurement system was far from the customer headquarters, a remote way for controlling the operations was mandatory. As additionnal challenge, the remote connection speed was limited.
Magentasys provided the acquisition system, the YES! libraries together two GUI, in order to solve this challenge.
The data, coming from a signal source (e.g. a big sized antenna), is acquired by the ADCs on the M9703A acquisition board, then computed in the on-board FPGA chip, using a polyfilterbank FFT, an efficient FFT algorithm. The data is then transmitted through the PCI express to the computer host.
The ‘Spectrometer’ application allow to drive the acquisition board, this being preset at predefined hours, then display and/or export the data in FITS, text format or HDF5. This latter format, using specific compression features, allowed to reduce the amount of data to be transmitted through the network. Also, a 'remote client' feature allow to control the acquisitions from afar and automate the data post processing.