OAI and LimeSDR-Mini

Here are the ref.sig.power values for band8:

5MHz, TX gain=77: the ref sig power is -20dBm
10MHz, TX gain=75: the ref sig power is -24dBm

Higher gain values resulted in increased EVM, so these are the highest TX gain values which produces reasonable EVM (1-2% EVM, 4-5% EVM peak).

On band8 the TX power of the Mini is also greater: it can push -4dBm total power out at 10MHz TX gain=75. In comparison, on 1800MHz the Mini was only able to produce -17dBm output at TX gain=80.

Here are the ref.sig.power values for band20:

5MHz, TX gain=76: the ref sig power is -20dBm
10MHz, TX gain=73: the ref sig power is -25dBm

Here are the ref.sig.power values for band7:

5MHz, TX gain=70: the ref sig power is -38dBm
10MHz, TX gain=73: the ref sig power is -39dBm

Please note that on band7 the frequency error is 12KHz or more, that is completely unacceptable. This is likely the cause of the bad EVM performance on this band as well.

Here are the ref.sig.power values for band1:

5MHz, TX gain=75: the ref sig power is -30dBm
10MHz, TX gain=73: the ref sig power is -36dBm

The frequency error on band1 is around 10KHz. According to 3GPP on 2GHz the freqeuncy error should be ±100Hz or less. This can affect if the UE can synch to the Lime Mini or not, and how stable the connection will be.

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