Chair: John Payne
Attendees: Belitsky (Chalmers), Claude (?), Lamb (OVRO), Lazareff (IRAM), Payne (NRAO), Rafal (NRAO), Webber (NRAO), White (NRAO), Wild (RUG)
Group agreed on recommending changing the specification to include extending Band 3 down to 84 GHz. There was a discussion of total power stability, and of possibly delaying meeting the existing specification for this parameter. Rafal will verify with the ASAC the stability requirements for Band 3. Webber would like the chance to discuss performance of the MMIC HFET with Erickson before making any final decision on making Band 3 an SIS Receiver; he will study this issue and generate a report. Preliminary results on a new MMIC wafer indicate good noise performance. John Payne will poll the engineers responsible for existing mm-wave receivers about their total power stability.
Group agreed to request change the wording of the polarization specification to indicate a limit on cross-polarization rather than orthogonality. The cross-polarization will be < -20 dB.
After much discussion, it was decided that the wording of specifications will be changed to say that optics specifications will be as described in the optics documents. Putting any rigid value on is too hard; we will be able to show "best effort" and provide links to references.
The group agreed that the noise temperature specifications are to be revised to reflect the noise added by the optics, and that the receiver noise will be referred to a plane between the receiver optics and the subreflector. The breakdown of noise contributions is only to be at the level of components supplied by different groups. There is too much detail in the specifications and it was suggested that some of the information could be done with ICD's. Some of these items are deferred until we have a system engineer for the Front End. Wild and Payne agreed to discuss how to identify such a person (volunteers are preferred but unlikely).
After some discussion of what configurations should be allowed, it was agreed to leave the sideband specifications as is for now.
New
Poll existing receiver builders to see what current stability results are - John Payne: Due 2001-Mar-26
ASAC to provide definite answers on radiometry - Marc Rafal: Due Date: 2001-Apr-02Old
Payne to provide US/Europe ICD templates - Due Date: 2001-Mar-19
Brown/Rafal will discuss with AEC JRDG issues (fall back plans, technology freeze, etc.) - Due Date: 2001-Mar-09
Brown/Rafal/Kurz will ask ASAC to designate preferred frequency range for Band 7 - Due Date: 2001-Apr-02
Next meeting will be 2001-Mar-29 at 1600 UT. Agenda will be to finish
going over the TBDs.
Minutes recorded and submitted by Carolyn White