Tianlai Analysis Teleconference

Peter Timbie (UW-Madison), Peter Timbie


  • Peter - LNA noise cross-coupling paper resubmitted on 15 September
  • Jixia - update on construction/observations at Hongliuxia.   See attached slides. 
  • Jixia - study of RFI reflected from airplanes.  Working with a team that is interested in RFI (but not radio astronomers).  Two experiments:   1) dishes pointed toward airplane track, but fixed.  2) dishes tracking the airplane.  (The airplane location is available with updates ~ every 2 seconds.  Jixia wrote code to operate the dish motors to track the airplanes.) In both cases Jixia is looking at waterfall plots of the correlator output.  In case 1, the waterfall plot shows strong RFI in the 760 - 785 MHz band that is known to come from the 5G cell phone band.  In addition, there are clear signatures of reflected signals with a duration of ~ 20 seconds from aircraft.   In case 2, with the telescope motors on, there appears to be strong RFI from the dish motors and it's not possible to see the  5G RFI or the signature of the reflected signal.     Could this be used for phase calibration?   There are lots of airplanes (every few hours) but they are at low elevation (25 degrees or lower).   Could look for signal appearing in sidelobes of dishes (or cylinders). 
  • Hangzhou collaboration meeting planning - Xuelei --> Postpone to future week
  • Other topics for this week or future
There are minutes attached to this event. Show them.
    • 8:00 AM 8:01 AM
      Minutes for last meeting (Sept 12) have been posted 1m
    • 8:01 AM 8:21 AM
      Update on construction at Hongliuxia site 20m
      Speakers: Jixia Li (NAOC), Kai He (NAOC)