OFDMA implementation in MATLAB in the presence of Path loss

Please if any one can solve my crucial problem of introducing the path loss in the transmitted signal. I am able to find the received power by the known formula of subtracting the transmitted power with path loss. But the main problem is that to find the Bit error or symbol error rate we need to introduce path loss in the transmitted signal. The main issue is that the signal is in the vector form but path loss is a single value in dB. Now how to put the effect of path loss in the signal. I would highly appreciate for upcoming replies.