Robust Packet Detector based Automatic Gain Control Algorithm for OFDM-based Ultra-WideBand systems

We propose a robust auto gain control (AGC) algorithm for OFDM-based ultra-wideband (UWB) system. In the UWB system, the transmitted signal power is limited to -41.25 dBm in a 1-MHz bandwidth. Therefore, it is difficult for front-end receiver operation by using traditional power estimation approach. Based on the proposed packet detector (PD), the signal power estimation is much more accurate. On the other hand, saturation of the ADC output is another critical issue. We provide a robust AGC convergence mechanism solving this problem. After the AGC operation converges, the received signal power is within the error margin relative to target power. This power error is less than 0.5 dB.