US 11,855,681 B2
Systems and methods for synchronization by transceivers with OQPSK demodulation
Jiaqiang Huang, Guangzhou (CN); and Jiapeng Zhang, Guangzhou (CN)
Assigned to Guangzhou On-Bright Electronics Co., Ltd., Guangzhou (CN)
Filed by GUANGZHOU ON-BRIGHT ELECTRONICS CO., LTD., Guangzhou (CN)
Filed on Nov. 9, 2020, as Appl. No. 17/093,372.
Application 17/093,372 is a continuation of application No. 16/124,983, filed on Sep. 7, 2018, granted, now 10,879,951.
Claims priority of application No. 201810936992.7 (CN), filed on Aug. 16, 2018.
Prior Publication US 2021/0159939 A1, May 27, 2021
Int. Cl. H04B 1/7073 (2011.01); H04B 1/709 (2011.01); H04L 27/38 (2006.01)
CPC H04B 1/7073 (2013.01) [H04B 1/709 (2013.01); H04L 27/3818 (2013.01); H04B 2201/694 (2013.01); H04B 2201/7073 (2013.01)] 28 Claims
OG exemplary drawing
 
1. A demodulator for processing an analog signal, the demodulator comprising:
one or more analog-to-digital converters configured to receive an analog signal and generate a digital signal based at least in part on the analog signal;
a correlator coupled to the one or more analog-to-digital converters and configured to generate a stream of correlation results including a first plurality of correlation results, a second plurality of correlation results, and a third plurality of correlation results, the first plurality of correlation results being different from the second plurality of correlation results by at least one correlation result, the second plurality of correlation results being different from the third plurality of correlation results by at least another correlation result;
a second storage configured to receive the stream of correlation results and including N storage units, N being a variable based on a frequency of the analog signal, such that N changes with the frequency of the analog signal being changed;
an adder coupled to the correlator and configured to receive first selected correlation results of the first plurality of correlation results and determine a first sum of the first selected correlation results, receive second selected correlation results of the second plurality of correlation results and determine a second sum of the second selected correlation results, and receive third selected correlation results of the third plurality of correlation results and determine a third sum of the third selected correlation results;
a first storage configured to receive and store the first sum at a first time, receive and store the second sum at a second time, and receive and store the third sum at a third time, the first time preceding the second time, the second time preceding the third time;
a symbol synchronization selector coupled to the first storage and configured to determine a point of symbol synchronization based at least in part on the first sum, the second sum and the third sum; and
a symbol decoder configured to:
receive the point of symbol synchronization; and
decode the analog signal based at least in part on the point of symbol synchronization.