US 11,728,840 B2
Single chirp data alignment with early message rejection for chirp spread spectrum
David R. Hall, Provo, UT (US); Mark Hall, Smithfield, UT (US); John Robinson, Spanish Fork, UT (US); and Warren Willes, Alpine, UT (US)
Assigned to Sure-Fi, Inc., Provo, UT (US)
Filed by Sure-Fi Inc., Provo, UT (US)
Filed on Dec. 31, 2021, as Appl. No. 17/567,006.
Claims priority of provisional application 63/132,642, filed on Dec. 31, 2020.
Prior Publication US 2022/0209813 A1, Jun. 30, 2022
Int. Cl. H04B 1/69 (2011.01); H04L 27/26 (2006.01)
CPC H04B 1/69 (2013.01) [H04L 27/265 (2013.01); H04B 2001/6912 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method for message validation in chirp spread spectrum (CSS) comprising:
receiving one or more training chirps in a preamble of a message;
processing each of the one or more training chirps using a fast-Fourier transform (FFT) to generate an FFT result;
accumulating the FFT results of the one or more training chirps;
determining that the accumulated FFT results exceed a detection threshold;
determining, based on the detection, a symbol timing;
receiving a single opposite chirp in the preamble of the message using the determined symbol timing, wherein the single opposite chirp is subsequent to the one or more training chirps, and wherein the single opposite chirp comprises an identifier;
decoding the single opposite chirp to determine the identifier; and
terminating processing of the message when the determined identifier fails to match a predetermined identifier.