First light with JIVE Uniboard Correlator!

© JIVE

The JIVE Uniboard Correlator (JUC) is an FPGA-based correlator that can correlate two polarizations of four 16 MHz subbands for 32 stations on a single board, among other modes. The correlation engine is now well-tested and the commissioning process proceeds apace.

The Uniboard correlator's low power consumption and high data throughput makes it a very attractive candidate for eVLBI operations, and now that we are confident of the quality of its data products we are working towards tests of that functionality in the near future.

We have correlated a single 2.5-min scan of J1955+5131 from a recent EVN observation at 6 cm with seven stations: Effelsberg, Medicina, Noto, Onsala, Tianma, Zelenchukskaya, and Badary. We correlated the data with both the production SFXC software correlator and the JUC FPGA correlator, with eight subbands of 1024 channels each. The output signals after correlation agree within 1%.

The image shows the final images obtained from this scan with the two correlations. It can be clearly seen that both images are identical, showing a compact source with a peak brightness of 5.16 mJy/beam and a noise rms level of 0.39 mJy/beam. The synthesized beam is 3.9 x 0.86 mas, and contours start at 3 times the noise level with increments of square root of 2.