LOFAR1 operations stopped, telescope gearing up for 2.0 upgrade
August 31st was the last day on which we received data from LOFAR1. With the shutdown of LOFAR1 operations, over a decade of gathering and handling huge amounts of data came to an end. LOFAR1 operations have led to the publication of more than 750 scientific papers so far, and this number is still growing by about two papers per week. The end of LOFAR1 production operations does of course not mean the end of LOFAR (which became LOFAR ERIC last year): right now we are working hard on upgrading the LOFAR telescope to version 2.0, both in software and hardware.
Gargantuan Black Hole Jets Are Biggest Seen Yet
Astronomers have spotted the biggest pair of black hole jets ever seen, spanning 23 million light-years in total length. That’s equivalent to lining up 140 Milky Way galaxies back to back.
Second-Generation Starlink Satellites Leak 30 Times More Radio Interference, Threatening Astronomical Observations
Observations with the LOFAR (Low Frequency Array) radio telescope last year showed that first generation Starlink satellites emit unintended radio waves that can hinder astronomical observations. New observations with the LOFAR radio telescope, the biggest radio telescope on Earth observing at low frequencies, have shown that the second generation ’V2-mini’ Starlink satellites emit up to 32 times brighter unintended radio waves than satellites from the previous generation, potentially blinding radio telescopes and crippling vital research of the Universe.
European grant allows ASTRON astronomer Joe Callingham to study the space weather of other worlds
Dr Joe Callingham has received an ERC Starting Grant worth 1.5 million euros.
Dual Channel RF over Fiber
© Lesley Goudbeek
https://www.astron.nl/dailyimage/main.php?date=20170112
A couple of years ago a special module was developed for Ingram Networks, situated in England.
The Ingram module operates from 20kHz to 800MHz (not a typo) and over a hundred optical links have been shipped to Ingram. The modules are destined to be used for a railway project, where base stations connect to moving trains providing wireless internet to the passengers. The RFoF modules provide signal transport between base stations.
A dual channel RFoF module has been suggested and if it is easily achievable. As a Friday afternoon test, a dual channel RFoF module was made using previous developed single channel PCB’s (shown in upper picture). Instead of using a single laser, a dual laser module was used. This dual laser module is connected to 2 separate PCB’s (without any additional modifications). The same is done on the receiver side were a dual channel detector is connected to 2 separate PCB’s. The graph on the left show an old “normal” single channel RFoF module, and the right graph shows the modified dual channel RFoF Frankenstein (shown in the picture), where 2 separate signals are visible. And without any additional modifications, the results are not that far off of the original module. Reducing pin length and removing the unused detectors should improve stability.
This shows that a dual channel RFoF module is quite feasible and existing designs can be used. Plus the costs of a dual channel laser or detector is not significantly higher than 2 separate laser or detector modules. A dual channel can, for example, be used for transmitting both antenna polarizations and reduce the number of fibers needed by half. With a small PCB redesign, the total PCB size used can also be reduced. Sometimes a Friday afternoon can give insight into a lingering question.