US 11,870,550 B2
Ultra-low power data transmission method and apparatus
Pansoo Kim, Daejeon (KR); Soo Yeob Jung, Sejong-si (KR); and Joon Gyu Ryu, Daejeon (KR)
Assigned to Electronics and Telecommunications Research Institute, Daejeon (KR)
Filed by ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE, Daejeon (KR)
Filed on Jun. 29, 2021, as Appl. No. 17/361,575.
Claims priority of application No. 10-2020-0079954 (KR), filed on Jun. 30, 2020.
Prior Publication US 2021/0409142 A1, Dec. 30, 2021
Int. Cl. H04J 13/00 (2011.01); H04L 5/00 (2006.01); H04B 17/327 (2015.01); H04L 1/00 (2006.01); H04L 27/00 (2006.01); H04W 72/23 (2023.01); H04B 17/318 (2015.01)
CPC H04J 13/0051 (2013.01) [H04B 17/318 (2015.01); H04B 17/327 (2015.01); H04J 13/0044 (2013.01); H04L 1/0063 (2013.01); H04L 1/0071 (2013.01); H04L 5/0048 (2013.01); H04L 27/0014 (2013.01); H04W 72/23 (2023.01); H04L 2027/0065 (2013.01)] 2 Claims
OG exemplary drawing
 
1. An ultra-low power data transmission method to be performed by a user terminal of an ultra-low power data transmission system, the ultra-low power data transmission method comprising:
receiving downlink signals through a satellite network and a terrestrial network, respectively;
identifying received power of each of the received downlink signals; and
transmitting, to a gateway, collected data through one of the satellite network and the terrestrial network based on the identified received power of the downlink signals,
wherein the transmitting is performed using a different channel code and a preamble sequence based on a type of the network to be used for the transmitting;
wherein the transmitting comprises:
when the collected data is transmitted through the satellite network, estimating channel error information corresponding to a Doppler frequency error and a carrier frequency error through a downlink signal comprising control information and a pilot signal that is received from a satellite;
determining a transmission method for correcting the Doppler frequency error and the carrier frequency error based on the estimated and computed channel error information; and
transmitting, to the gateway, the collected data through the satellite network by first correcting the estimated and computed channel error information using the determined transmission method;
wherein the transmission method comprises at least one of a modulation method, a channel code rate-based method, or a transmission power-based method; and
wherein the ultra-low power data transmission method further comprises:
selecting, as the modulation method and the channel code, respectively, a differential binary phase-shift keying (BPSK) modulation method and a convolution code, based on a first amount of variation in the Doppler frequency error and a first amount of received signal-to-noise ratio (SNR); and
selecting, as the modulation method and the channel code, respectively, a coherent modulation method and a turbo code, based on a second amount of variation in the Doppler frequency error and a second amount of received SNR;
wherein the first amount is greater than the second amount.