# Negative transmit power in dBm

I am calculating the transmit power for $$K$$ single antenna IoT devices in an Indoor scenario. The receiver has 64 antennas. I am trying to minimize the transmit sum-power, i.e., $$\sum_k p_k$$, where $$p_k$$ is the transmit power of $$k$$-th IoT device. The noise power is -168dBm/Hz. The BW is 180kHz and the transmit frequency is 2.4GHz. I have a minimum requirement for the SNR.

Upon solving I am getting a transmit power in range of -60 dBm to -70dBm. Is the transmit power feasible considering the noise is too less and the path loss is minimal considering a room size of 10m, i.e, the max distance between transmitter and receiver is 10m?

• I don't think I really understand your question. You have your SNR requirement. You have the noise density and the bandwidth and you have the transmission distance, from which you can get the path loss. I guess you want to compute the necessary transmit power? Then compute the power balance by using the Friis formula. – Terahertz Sep 27 '19 at 14:01