US 12,088,361 B2
Contactless card reading employing gain and attenuation control
Hyunjae Kang, Seoul (KR)
Assigned to SAMSUNG ELECTRONICS CO., LTD., Suwon-si (KR)
Filed by SAMSUNG ELECTRONICS CO., LTD., Suwon-si (KR)
Filed on May 4, 2023, as Appl. No. 18/312,277.
Application 18/312,277 is a continuation of application No. 17/699,459, filed on Mar. 21, 2022, granted, now 11,671,147.
Application 17/699,459 is a continuation of application No. 17/023,923, filed on Sep. 17, 2020, granted, now 11,283,483, issued on Mar. 22, 2022.
Claims priority of application No. 10-2019-0168535 (KR), filed on Dec. 17, 2019.
Prior Publication US 2023/0275618 A1, Aug. 31, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. H04B 5/00 (2024.01); H04B 1/38 (2015.01); H04B 5/02 (2006.01); H04B 5/26 (2024.01); H04B 5/72 (2024.01); H04B 5/77 (2024.01); H04B 5/79 (2024.01)
CPC H04B 5/72 (2024.01) [H04B 5/266 (2024.01); H04B 5/77 (2024.01); H04B 5/79 (2024.01)] 16 Claims
OG exemplary drawing
 
1. A contactless integrated circuit (IC) card reader configured to communicate with a contactless IC card, comprising:
an antenna circuit;
a variable amplifier configured to amplify a carrier signal at an amplification gain and to output the amplified carrier signal to the antenna circuit as a transmission signal;
a variable attenuator configured to attenuate a receive signal received through the antenna circuit at an attenuation ratio; and
a controller configured to decrease both the amplification gain of the variable amplifier and the attenuation ratio of the variable attenuator under a condition in which a level of the receive signal is smaller than a reference level.