Power consumption of Global Positioning System (GPS) acquisition is a great challenge\nfor energy-constrained applications. In this work, a metric named acquisition mean computation\noverhead is proposed to measure the energy cost. A novel multi-peak double-dwell (MP/DD)\nacquisition method for GPS weak signal is proposed. It adopts multi-peak correlation results as\ncandidates in the first acquisition dwell and selects the largest one as the final acquisition result\nin the second acquisition dwell. Theoretical analysis and numerical simulation are presented in\ndetail. Meanwhile, the very-large-scale integration (VLSI) implementation of coarse- and fine-grained\nacquisition engines applied to the proposed method is done. The detection probability and acquisition\nmean computation overhead are simulated using the Monte-Carlo method, and its mean acquisition\npower is tested with an actual chip. We fabricated the GPS signal acquisition engine with a 40 nm\ncomplementary metal oxide semiconductor (CMOS) process. The simulation results demonstrate\nthat detection probability is promoted from 18% to 67% when signal power is equal to 23 dB/Hz.\nThe acquisition mean computation overhead is reduced greatly by 64%. Measurement results show\nthat the energy consumption of this design is only 21.5% of the conventional double-dwell/maximum\n(DD/MAX) method.
Loading....