srsran / srsRAN_4G

Open source SDR 4G software suite from Software Radio Systems (SRS) https://docs.srsran.com/projects/4g
https://www.srsran.com
GNU Affero General Public License v3.0
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what is the meaning of tx_gain and rx_gain in enb.conf #1040

Open coolcoollly opened 1 year ago

coolcoollly commented 1 year ago

Issue Description

There are tx_gain and rx_gain in enb.conf, like 40db and 35db. But I don't konw how they scale signal. Can they really amplify the transmitted signal by 40db or more in the real world.

##################################################################### [rf]

dl_earfcn = 3350

tx_gain = 40 rx_gain = 35

device_name = auto

zikkuratti commented 1 year ago

if your hardware output 1Watt into system then 40db upscale it in 10000 Watt onfly and so on... try this calculator https://www.rapidtables.com/electric/decibel.html also for real values you can try spectroanalyze your signal whith sdr or some special overpriced hardware. About amplification, yes they can, but chip amplification hardware can get parasite noise and here we have some rule - more quality more price, weight and so on.