研究成果藝廊
Noise/Tone Calibration Plate, YTLA Project
This custom plate assembly was design to generate and distribute 2 to 18 GHz wide-band noise or CW tone for in-situ calibration and test of the I/Q down converters and digital backend correlator system. The plate is mounted on the platform and is controlled remotely via Ethernet.
The requirements for this noise plate was fairly stringent so as to not adversely affect the extremely sensitive correlator when performing astronomical observations. Measured cross-talk between antenna channels was in excess of 140 dB across the entire 2-18 GHz band. The "Noise ON" to "Noise OFF" isolation was estimated to be 180 dB based on three cascaded Dow-Key SPDT switches, each with 60 dB isolation. The assembly was designed and constructed using recycled parts from the decommissioned AMiBA analog correlator system. Design/assembly/test - Derek Kubo, system test - Ranjani Srinivasan/Kai-Yang Lin.