I’ve given up on trying to get LimeAPI working (see above) and switched over to libusb which at least allows me to run the scripts. I have made several passes against a chinese 900MHz-ish dipole and the results I’m seeing don’t appear to be working correctly. Specifically, my SWR and Smith charts are all over the place, and S11 > 0 near what should be the antenna’s tuned freq.
Hardware Setup
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LimeSDR USB:
python2 findLimeSDR.py
Searching for LimeSDR…
LimeSDR info:
FW_VER : 4
DEV_TYPE : 14
LMS_PROTOCOL_VER : 1
HW_VER : 4
EXP_BOARD : 1LMS7002M info:
VER : 7
REV : 1
MASK : 1 -
Chinese-grade 0Ω SMA short
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Mini Circuits ZFDC-15-5-S
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LimeSDR RX1_L wired to CPL
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LimeSDR TX2_1 wired to 10dba attenuator to OUT
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Short and DUT connected to IN
Software Setup
Sweep configuration in measureVNA.py and calculateVNA.py:
startFreq = 700e6
endFreq = 1100e6
nPoints = 401
Setup for TX low freq LNA in measureVNA.py:
TRF.SEL_BAND1_TRF = 1
TRF.SEL_BAND2_TRF = 0
