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NTU LNA Noise Figure Review II. Jerry Shiao National Taiwan University. Current Issues. Some LNAs seem much worse than the others. Ratty noise temperature from 600 to 800MHz. NF Test Set-up. HP N8975A NF meter HP 346C noise source LNA #21, #31, #52 and #56. LNA#52 NF Test I.
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NTU LNA Noise Figure Review II Jerry Shiao National Taiwan University
Current Issues • Some LNAs seem much worse than the others. • Ratty noise temperature from 600 to 800MHz
NF Test Set-up • HP N8975A NF meter • HP 346C noise source • LNA #21, #31, #52 and #56
Test Results • Bandwidth and point average affect the results. • 600-800MHz noise is not clear but may be partially due to the circuit. The upper 3dB frequency of 1st stage in the LNAs is about 700-800MHz. • HP8970B system temperature may be better than HP N8975A • The NF trends look different from those with HP8970B
Next step • Unfortunately we still got un-conclusive results. • We has bought a HP8970B to mimic the measurement in HW. • We will be more careful when sealing the box cover and connectors with silver glue.