Normalized-energy-detector serial search acquisition scheme for packet communication systems with non-ideal AGC

Automatic gain control (AGC) is extensively used in practical packet communication systems, but the effect is generally not taken into account in code acquisition research. A dedicated investigation in this paper highlights the effect of non-ideal AGC on the performance of the extensively used envelope-detector (ED) serial search acquisition (SSA) scheme, for the performance loss due to non-ideal AGC is significant. To improve the acquisition performance and eliminate the effect of AGC, a normalized-energy-detector (NED) SSA scheme is proposed. Theoretical analysis and numerical results on the performance of the proposed scheme are given. Simulations are also performed to further justify the analysis and numerical results. Performance comparisons showthat the proposed scheme outperforms the ED SSA scheme with ideal and non-ideal AGC. Moreover, the proposed scheme is free from influence of AGC, and no performance loss can be found even when using non-ideal AGC for the proposed method.