Hi,
I am programmatically trying to measure RSSI for RX A+B using LNA_L and have read Ricardas’ postings on RSSI measurement. I’ve read that each channel should be able to have its own frequency, but have been unable to accomplish this. Also, although the RSSI values are changing (I’m measuring them every 100 msec and averaging 2^12 samples), when I apply an external -35 dBm to either LNA_L antenna port, no appreciable change occurs to either RSSI level. I have just downloaded and rebuilt the LimeSuite shared lib from git and have run LimeUtil --update. Below is the output I’m generating so that you can see various parameters . I’m using the LMS7002 and IConnection classes to set parameters and make SPI changes.
One thing I see is that RX Calibration fails:
SelfCalibration error: MCU working too long 52
LimeSDR-USB, media=USB 3.0, module=STREAM, addr=1d50:6108, serial=0009060A02431120
[INFO] Estimated reference clock 30.7195 MHz
[INFO] Selected reference clock 30.720 MHz
[INFO] LMS7002M cache /Users/abigbee/.limesuite/LMS7002M_cache_values.db
Set Active Channel ChA
Reading registers
Refclk 30.7 (MHz)
Frequency CGEN 371.715 (MHz)
Sample rate 46.464 (Msps)
LNA 30.0 (db)
TIA 12.0 (db)
PGA -1.0 (db)
Vtemp 0x00AB, Vptat 0x00A9, Vdiff = -1.80, temp= 38.697
Temperature 38.7 (C)
HBD_OVR_RXTSP 0 [decimation ratio 2^(1+0) = 2]
AGC Open Loop Gain K 0
Writing registers
LNA Gain set to → 10.0
Path RFE → PATH_RFE_LNAL
SetFReqencyCGEN vco found 2.88E9
6 DIV_OUTCH_CGEN
92 0.0 0 NT_SDM_CGEN-intpart dFrac gFrac
3.072E7 ← GetReferenceClk_SX
9.292875E7 ← GetReferenceClk_TSP
2 TuneVCO VCO_CGEN results in: TuneVCO(SXR) - VCO too low
3 SetFrequencySX results in: TuneVCO(SXR) - VCO too low
4 SetFrequencyCGEN results in: SetFrequencyCGEN(240 MHz) failed:
INT: 92 FRAC: 786432 DIV_OUTCH_CGEN: 5
VCO: 2880 MHz RefClk: 30.72 MHz
TuneVCO(CGEN) - VCO too high
Sample rate → 30.000 (Msps)
Rereading registers
Path RFE PATH_RFE_LNAL
Frequency CGEN 240.000 (MHz)
Sample rate 30.000 (MHz)
CGEN FREQ 240.0 (MHz), resulting sample rate is 30.000 (Msps)
HBD_OVR_RXTSP 0 [decimation ratio 2^(1+0) = 2]
Frequency CGEN 240.000 (MHz)
Sample rate 30.000 (MHz, CGEN/4/decimation ratio)
NCO Frequency 25.826 (MHz)
Path RFE PATH_RFE_LNAL
Set Active Channel ChB
Reading registers
Refclk 30.7 (MHz)
Frequency CGEN 240.000 (MHz)
Sample rate 30.000 (Msps)
LNA 30.0 (db)
TIA 12.0 (db)
PGA -1.0 (db)
Vtemp 0x00AB, Vptat 0x00A9, Vdiff = -1.80, temp= 38.697
Temperature 38.7 (C)
HBD_OVR_RXTSP 0 [decimation ratio 2^(1+0) = 2]
AGC Open Loop Gain K 0
Writing registers
LNA Gain set to → 10.0
Path RFE → PATH_RFE_LNAL
SetFReqencyCGEN vco found 2.88E9
6 DIV_OUTCH_CGEN
92 0.0 0 NT_SDM_CGEN-intpart dFrac gFrac
3.072E7 ← GetReferenceClk_SX
6.0E7 ← GetReferenceClk_TSP
2 TuneVCO VCO_CGEN results in: TuneVCO(SXR) - VCO too low
3 SetFrequencySX results in: TuneVCO(SXR) - VCO too low
4 SetFrequencyCGEN results in: SetFrequencyCGEN(240 MHz) failed:
INT: 92 FRAC: 786432 DIV_OUTCH_CGEN: 5
VCO: 2880 MHz RefClk: 30.72 MHz
TuneVCO(CGEN) - VCO too high
Sample rate → 30.000 (Msps)
Rereading registers
Path RFE PATH_RFE_LNAL
Frequency CGEN 240.000 (MHz)
Sample rate 30.000 (MHz)
CGEN FREQ 240.0 (MHz), resulting sample rate is 30.000 (Msps)
HBD_OVR_RXTSP 0 [decimation ratio 2^(1+0) = 2]
Frequency CGEN 240.000 (MHz)
Sample rate 30.000 (MHz, CGEN/4/decimation ratio)
NCO Frequency 0.000 (MHz)
Path RFE PATH_RFE_LNAL
############################################################
Rx calibration using RSSI INTERNAL ON BOARD loopback
Rx ch.B @ 418.05 MHz, BW: 60 MHz, RF input: LNAL, PGA: 11, LNA: 4, TIA: 3
Performed by: MCUMCU algorithm time: 0 ms
Current MCU firmware: 3, DC/IQ calibration full
MCU Ref. clock: 30.72 MHz
MCU algorithm time: 92 ms
SelfCalibration error: MCU working too long 52
A sample rate → 30.00
A SX Frequency → 418.05 (MHz)
B sample rate → 30.00
B SX Frequency → 418.05 (MHz)
channel level dbfs channel level dbfs
A 32 -68.99 B 32 -68.99
A 32 -68.99 B 32 -68.99
A 32 -68.99 B 31 -69.27
A 32 -68.99 B 31 -69.27
A 32 -68.99 B 32 -68.99
A 33 -68.72 B 32 -68.99
A 32 -68.99 B 31 -69.27
A 32 -68.99 B 32 -68.99
A 32 -68.99 B 32 -68.99
A 32 -68.99 B 31 -69.27
A 32 -68.99 B 31 -69.27
A 33 -68.72 B 31 -69.27
A 32 -68.99 B 32 -68.99