  This paper presents a novel LoRa (Long Range) receiver operating in frequency
selective Multi-Path Channel (MPC). The dechirped received LoRa wave-forms
under MPC allows us to derive a simple and efficient LoRa receiver scheme by
using a MF (Matched Filter) approach that aims to maximize the SNR
(Signal-to-Noise Ratio) at the symbol index frequency of the DFT output. We
show that the MF receiver can be seen as RAKE structure where interference
peaks related to multipath, exhibited at DFT output, are recombined in a
constructive way. Detection performance is driven by channel energy and the
benefit of this novel MF/RAKE receiver over original coherent and non-coherent
receiver appears only for MPC that exhibits significant paths energy. These two
MF and RAKE receivers have however different implementation complexities that
are studied in details. We provide in that sense recommendations on which
receiver variant to use for real operations, depending on complexity
constraints. Finally, the proposed MF/RAKE receiver outperforms previous
results on TDEL (Time Delay Estimation LoRa) receiver over MPC, especially at
low SNR and higher LoRa Spreading Factor (SF) parameter, at the cost of higher
but reasonable complexity.
