An improved method for TOA analysis in MMW systems

The energy detector (ED) receiver is a promising solution for time-of-arrival (TOA) based positioning using millimeter-wave (MMW) pulses in multipath environments due to its simple circuitry. Usually in ED receiver, the optimum threshold values required for TOA estimates cannot be acquired particularly when the signal-to-noise ratio (SNR) is low. In this paper, a new ED receiver is discussed based on the results of the ensemble empirical mode decomposition (EEMD) of the received MMW pulses. Meanwhile, the extreme learning machine (ELM) is used to determine optimum threshold values via analyzing the characteristics of the calculated energy samples. The discussed technique can provide efficient threshold values with lower complexity and lower sampling frequency. The proposed receiver is evaluated using measurements obtained in IEEE 802.15.3c models, which show its effectiveness compared to the conventional ED receivers.