Max output power for US915

[reissjason]

Is 26 dBm EIRP the correct output power for US915. FCC allows +36 dBm EIRP for 500 KHz transmissions, +30 conducted with upto +6 dBi antenna gain.

The gain is subtracted from the s2ctx->txpow before being sent to the hal, this makes US915 with this code output at radio power +23 dBm if +3 dBi antenna is configured.

basicstation/src/s2e.c

Line 1024 in ba4f85d

s2ctx->txpow = 26 * TXPOW_SCALE;

[reissjason]

I see in regional parameters a quasi limit of +26 marked in practice. This suggests it could be possible for a gateway to exceed this if it passes PSD certification for FCC. Was there a reason that "in practice" only +26 dBm was achievable? Were there drawbacks to gateway power output above +26?

Regardless the antenna gain setting is not accounted correctly.