-- StevenWhite - 19 Oct 2007

Block Diagram

Drawings

Custom Passive Substrates

Performance Issues
  • Impact of Expanded RF bandwidth on Image Rejection : plot

Measured Results

Lessons Learned

One hard lesson I take away from this project is that spurs are the inevitable consequence of ANY multiple-conversion scheme. You can attenuate them as much as you want, but they will always be present at some level. That being the case, the best way to get rid of them is to avoid multiple-conversions altogether, especially in an integrated receiver, and especially on a single-dish instrument. That wasn't an option on the prototype array since we wanted to multiplex the IFs, and a single downconversion to IF less than ~6 GHz wouldn't provide adequate image rejection. But for the 60 element array, the IDM2's (or another single-downconversion approach) could be used with an updated IF Transmission System and the spurs would no longer be an issue.

There is way, however, by tuning both LO1 and LO2 together, to avoid seeing any spurs of any order in the IF passband:
Topic attachments
I Attachment Action Size Date Who Comment
40t3b.pdfpdf 40t3b.pdf manage 114 K 2008-02-06 - 16:26 MatthewMorgan  
40t3b_sim.pdfpdf 40t3b_sim.pdf manage 30 K 2008-02-06 - 16:26 MatthewMorgan  
IDM1.pdfpdf IDM1.pdf manage 142 K 2008-02-22 - 09:27 MatthewMorgan  
IDM1_block_diagram.pdfpdf IDM1_block_diagram.pdf manage 113 K 2008-02-22 - 09:19 MatthewMorgan  
IDM1_rev2.pdfpdf IDM1_rev2.pdf manage 83 K 2008-05-02 - 11:21 MatthewMorgan  
IDM1_spur_avoidance.docdoc IDM1_spur_avoidance.doc manage 980 K 2009-09-08 - 12:15 MatthewMorgan  
IDM2.pdfpdf IDM2.pdf manage 138 K 2008-02-22 - 09:27 MatthewMorgan  
IDM2_block_diagram.pdfpdf IDM2_block_diagram.pdf manage 77 K 2008-02-22 - 09:18 MatthewMorgan  
IDM2_data.pdfpdf IDM2_data.pdf manage 21 K 2009-09-02 - 15:49 MatthewMorgan  
IDM2_rev2.pdfpdf IDM2_rev2.pdf manage 79 K 2008-05-02 - 11:21 MatthewMorgan  
IDM_meas_summary.docdoc IDM_meas_summary.doc manage 3 MB 2009-09-02 - 15:47 MatthewMorgan  
RF_filter_comparison.jpgjpg RF_filter_comparison.jpg manage 109 K 2008-02-06 - 11:33 MatthewMorgan  
adapter.pdfpdf adapter.pdf manage 76 K 2008-02-22 - 09:28 MatthewMorgan  
block_diagram1-Model.pdfpdf block_diagram1-Model.pdf manage 200 K 2007-10-19 - 13:25 StevenWhite  
board_dim.pdfpdf board_dim.pdf manage 171 K 2008-05-02 - 11:17 MatthewMorgan  
idm1_results.pptppt idm1_results.ppt manage 531 K 2008-08-07 - 15:42 MatthewMorgan  
k22bpf1.pdfpdf k22bpf1.pdf manage 105 K 2007-12-10 - 18:00 MatthewMorgan  
k22bpf1_sim.pdfpdf k22bpf1_sim.pdf manage 36 K 2007-12-10 - 18:01 MatthewMorgan  
k22bpf2.pdfpdf k22bpf2.pdf manage 106 K 2007-12-13 - 17:11 MatthewMorgan  
k22bpf2_sim.pdfpdf k22bpf2_sim.pdf manage 36 K 2007-12-13 - 17:11 MatthewMorgan  
k8lpf1.pdfpdf k8lpf1.pdf manage 107 K 2007-12-10 - 18:01 MatthewMorgan  
k8lpf1_sim.pdfpdf k8lpf1_sim.pdf manage 35 K 2007-12-10 - 18:01 MatthewMorgan  
k8lpf2.pdfpdf k8lpf2.pdf manage 76 K 2008-03-20 - 15:27 MatthewMorgan  
k8lpf2_sim.pdfpdf k8lpf2_sim.pdf manage 13 K 2008-03-20 - 15:28 MatthewMorgan  
ksplit1.pdfpdf ksplit1.pdf manage 116 K 2007-12-10 - 18:02 MatthewMorgan  
ksplit1_sim.pdfpdf ksplit1_sim.pdf manage 38 K 2007-12-10 - 18:02 MatthewMorgan  
prb42b.pdfpdf prb42b.pdf manage 97 K 2007-12-10 - 18:02 MatthewMorgan  
prb42b_sim.pdfpdf prb42b_sim.pdf manage 30 K 2007-12-10 - 18:02 MatthewMorgan  
up42.pdfpdf up42.pdf manage 96 K 2008-02-06 - 11:27 MatthewMorgan  
up42_sim.pdfpdf up42_sim.pdf manage 30 K 2008-02-06 - 11:28 MatthewMorgan  
Topic revision: r14 - 2016-11-28, StevenWhite
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