Patents by Inventor Cheol-Su Kim

Cheol-Su Kim has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11121693
    Abstract: Technologies directed to a wireless device with RF port impedance detection using concurrent radios are described. One wireless device includes an impedance detection circuit with a bi-directional RF coupler and switching circuitry. A processing device controls the switching circuitry to i) couple the bi-directional RF coupler between a first radio and a first RF port and a second radio and a second RF port. The processing device causes a first radio to send a first signal and a second radio to measure a first receive signal strength indicator (RSSI) value of a first reflected signal. The processing device determines that the first RSSI value exceeds a threshold, the threshold representing an impedance mismatch condition at or beyond the first RF port. The processing device sends a message indicative of the impedance mismatch condition to a second device.
    Type: Grant
    Filed: January 16, 2020
    Date of Patent: September 14, 2021
    Assignee: Amazon Technologies, Inc.
    Inventors: Nathan Labadie, Kun Ting Tsai, Cheol Su Kim, Kalyan Teja Posani, Omar Fawazhashim Zakaria
  • Publication number: 20210280613
    Abstract: The present disclosure relates to a display substrate. The display substrate may include a substrate, a first lower gate electrode, an insulation pattern, a first insulation layer, and a first active pattern. The first lower gate electrode may be disposed on the substrate. The insulation pattern may be disposed on and patterned to correspond to the first lower gate electrode and may include a silicon nitride. The first insulation layer may be disposed on the insulation pattern and may include a silicon oxide. The first active pattern may be on the first insulation layer and formed of oxide semiconductor and may include a first channel region overlapping the first lower gate electrode and a first wiring region disposed on a side of the first channel region.
    Type: Application
    Filed: September 21, 2020
    Publication date: September 9, 2021
    Inventors: Se Myung KWON, Duk Young KIM, Young Kuk KIM, Cheol Su KIM, Yu Ri OH
  • Patent number: 11075465
    Abstract: Technologies for wireless network devices with surface-link antenna systems mounted on exterior surfaces of buildings are described. One wireless network device includes a housing with a circuit board and a first antenna port. A processor, a first antenna, a first wireless local area network (WLAN) radio, and a second WLAN radio are disposed on the circuit board. The first WLAN radio communicates with a radio of a client device using the first antenna over a first line-of-sight (LOS) or non-LOS wireless link (e.g., 2.4 GHz) inside the building. The second WLAN radio communicates with a radio of a second wireless network device using the second antenna over a second LOS wireless link (e.g., 5 GHz) that is external to the building. The first antenna is located inside the building and the second antenna is located along an exterior surface of the building.
    Type: Grant
    Filed: July 13, 2018
    Date of Patent: July 27, 2021
    Assignee: Amazon Technologies, Inc.
    Inventors: Tzung-I Lee, Omar Fawazhashim Zakaria, Kwok Shing Lee, Kalyan Teja Posani, Ali Mirkamali, Cheol Su Kim, In Chul Hyun
  • Patent number: 11043985
    Abstract: Technologies directed to cable-loss compensation are described. An apparatus includes a triplexer, a front-end module (FEM) circuit, and a control circuit. The triplexer is coupled to a radio frequency (RF) cable. The triplexer receives a first RF signal and a DC power signal from a device via the RF cable and sends a detection signal being indicative of a transmit power level of the first RF signal to the device via the RF cable. The transmit power level includes an insertion loss of the RF cable. The FEM circuit is coupled to the triplexer and includes a power amplifier (PA). The control circuit is coupled to the triplexer and measures the transmit power level of the first RF signal and converts the first RF signal into the detection signal. The control circuit sends the detection signal back to the device via the RF cable and enables the PA.
    Type: Grant
    Filed: June 3, 2020
    Date of Patent: June 22, 2021
    Assignee: Amazon Technologies, Inc.
    Inventors: Nathan Labadie, Cheol Su Kim, Ravi Ichapurapu, Kalyan Teja Posani, Omar Fawazhashim Zakaria, In Chul Hyun
  • Publication number: 20210176648
    Abstract: Technologies directed to a wireless network with a cascaded star topology with multiple devices at multiples nodes are described. In one wireless network, multiple devices are manufactured as a common device type and deployed at different nodes of the wireless network. The devices are configured to operate as a base station (BS) role, a gateway (GW) role, a relay (RL) role, or a customer station (STA) role. The nodes can be a base station node (BSN), a relay node (RLN), or a customer premises equipment (CPE) node. One node can be a first-tier hub of the cascaded star topology and another node can be a second-tier hub of the cascaded star topology.
    Type: Application
    Filed: December 9, 2019
    Publication date: June 10, 2021
    Inventors: Nathan Labadie, Tzung-I Lee, Omar Fawazhashim Zakaria, Subram Narasimhan, Cheol Su Kim
  • Publication number: 20210176805
    Abstract: Technologies directed to a wireless network device with a single hardware architecture that supports multiple devices roles through software configuration are described. One wireless network device includes a housing with an RF connector and a circuit board with a first radio coupled to an internal antenna and a second radio coupled to an external antenna via the RF connector. The second antenna is mounted on an exterior surface of the building and coupled to the RF connector via an RF cable. The wireless network device establishes a first wireless link between the first radio and a radio of a second device via the first antenna and a second wireless link between the second radio and a radio of a third device via the second antenna. The second device can be a second wireless network device that is programmed to operate as a gateway, the gateway being mounted outside of the building.
    Type: Application
    Filed: December 9, 2019
    Publication date: June 10, 2021
    Inventors: Nathan Labadie, Reshma Suresh, Ali Mirkamali, Cheol Su Kim, Omar Fawazhashim Zakaria, Kwok Shing Lee, Kalyan Teja Posani
  • Patent number: 10887026
    Abstract: Technologies directed to antenna disconnection detection of distributed radio frequency (RF) ports in a wireless network are described. One method receives data from the wireless devices and generates an RSSI matrix including multiple elements, each storing a receive signal strength indicator (RSSI) value indicative of a signal strength of a wireless link between a transmitter-receiver pair. The method identifies a characteristic pattern in the RSSI matrix. The characteristic pattern includes i) two or more RSSI values in a same row being less than the threshold value and ii) two or more RSSI values in a same column being less than the threshold value. The method stores an indication that an antenna is disconnected from an RF port and sends a command to the second wireless device that causes the second wireless device to disable a radio that is coupled to the RF port.
    Type: Grant
    Filed: February 18, 2020
    Date of Patent: January 5, 2021
    Assignee: Amazon Technologies, Inc.
    Inventors: Kun Ting Tsai, Nathan Labadie, Cheol Su Kim, Haritha Tamvada, Omar Fawazhashim Zakaria
  • Patent number: 10880903
    Abstract: A method includes determining, by a cloud computing system, a number of radar events detected by wireless access point (WAP) devices of a wireless mesh network and by channels associated with respective ones of the WAP devices. The method includes determining a first WAP device has detected a fewest number of radar events and that a first DFS channel, of the first WAP device, has detected a fewest number of radar events as compared with a number of radar events detected via each of the other DFS channels of the first WAP device. The method includes assigning the first WAP device to be a master on the first DFS channel and transmitting, to the first WAP device, a message containing first assignment information regarding the first WAP device being assigned as the master on the first DFS channel.
    Type: Grant
    Filed: January 17, 2019
    Date of Patent: December 29, 2020
    Assignee: Amazon Technologies, Inc.
    Inventors: Kun Ting Tsai, Kiran Kumar Edara, Sarang Wagholikar, Omar Fawazhashim Zakaria, Ashish Kumar Shukla, Cheol Su Kim
  • Patent number: 10862518
    Abstract: Technologies directed to a wireless device with a Radio Frequency (RF) Decibel-Scaled Wireless Interference Detector that provides accurate energy readings of a channel through decibel-scaled output voltage are described. One method of the wireless device includes receiving a first RF signal via an antenna and converting the first RF signal to a multiple samples using a sampling rate, each sample including a digital value of a decibel-scaled output voltage. The method converts each of the samples to an energy value using a voltage-to-energy lookup table and determines a congestion level of a channel using the energy values.
    Type: Grant
    Filed: December 6, 2019
    Date of Patent: December 8, 2020
    Assignee: Amazon Technologies, Inc.
    Inventors: Nathan Labadie, Kun Ting Tsai, Cheol Su Kim, Kwok Shing Lee, Haritha Tamvada
  • Patent number: 10748190
    Abstract: Provided are an apparatus for managing customer information, a method for managing customer information, a system for managing customer information, and a non-transitory computer readable storage medium having a computer program recorded thereon. That is, customer identification information may be transmitted to a customer managing apparatus through a customer identification information receiving apparatus positioned in the store. The customer managing apparatus may transmit customer management information corresponding to the customer identification information to a store managing apparatus in the store and user equipment of a clerk. The customer may be managed in the store based on the customer management information. Therefore, it is possible to indirectly acquire customer information from the customer and properly provide required information to the customer.
    Type: Grant
    Filed: November 24, 2015
    Date of Patent: August 18, 2020
    Assignee: SK Planet Co., Ltd.
    Inventors: Cheol Su Kim, Min Kyo Shin, Hwa Yeon Lee, Hee Jeong Kim
  • Patent number: 10616904
    Abstract: A device includes first and second directional antennas, an omnidirectional antenna, and a switch selectively coupled between the first directional and omnidirectional antennas. A first radio includes first RF circuitry. A switch selectively couples the first omnidirectional antenna or the first directional antenna to the first radio. A second radio is coupled to the second directional antenna and includes second RF circuitry. An application processor receives, from first RF circuitry, a first radio frequency performance indicator (RFPI) value for signals received over the omnidirectional antenna, a second RFPI value for signals received over the first directional antenna, and, from the second RF circuitry, a third RPI value for signals received over the second directional antenna. The application processor determines a best RFPI value, selects an antenna corresponding to the best RFPI value, and selects a radio corresponding to the selected antenna.
    Type: Grant
    Filed: January 22, 2018
    Date of Patent: April 7, 2020
    Assignee: Amazon Technologies, Inc.
    Inventors: Ali Mirkamali, Tzung-I Lee, Omar Fawazhashim Zakaria, Kalyan Teja Posani, In Chul Hyun, Cheol Su Kim
  • Patent number: 10581155
    Abstract: Antenna structures and methods of operating the same are described. One apparatus includes a processing device that executes an active interference cancellation (AIC) algorithm and radio frequency front-end (RFFE) circuitry coupled to the processing device. The RFFE circuitry includes two RF couplers, a fixed-delay filter, and an interference compensation circuit part of an electrical path between the two RF couplers. The AIC algorithm is operable to control the interference compensation circuit to adjust a phase, an amplitude or both of a copy of a first RF signal transmitted on a first antenna to remove corresponding interference in a second RF signal received at a second antenna that is caused by the first RF signal. The processing device triggers a re-calibration in the AIC algorithm when the digital values, received from a power detector circuit, indicate a change in impedance that exceeds a threshold.
    Type: Grant
    Filed: September 27, 2018
    Date of Patent: March 3, 2020
    Assignee: Amazon Technologies, Inc.
    Inventors: Adrian Gradinaru, Morris Yuanhsiang Hsu, Cheol Su Kim, Jaiyoung Park
  • Publication number: 20200021038
    Abstract: Technologies for wireless network devices with surface-link antenna systems mounted on exterior surfaces of buildings are described. One wireless network device includes a housing with a circuit board and a first antenna port. A processor, a first antenna, a first wireless local area network (WLAN) radio, and a second WLAN radio are disposed on the circuit board. The first WLAN radio communicates with a radio of a client device using the first antenna over a first line-of-sight (LOS) or non-LOS wireless link (e.g., 2.4 GHz) inside the building. The second WLAN radio communicates with a radio of a second wireless network device using the second antenna over a second LOS wireless link (e.g., 5 GHz) that is external to the building. The first antenna is located inside the building and the second antenna is located along an exterior surface of the building.
    Type: Application
    Filed: July 13, 2018
    Publication date: January 16, 2020
    Inventors: Tzung-I Lee, Omar Fawazhashim Zakaria, Kwok Shing Lee, Kalyan Teja Posani, Ali Mirkamali, Cheol Su Kim, In Chul Hyun
  • Patent number: 10447378
    Abstract: Network hardware devices organized in a wireless mesh network (WMN) in which a home access node (HAN) device that includes a first set of radios, each of the first set of radios being coupled to a beam-steering antenna and each of the first set of radios establishing a first point-to-point (PtP) wireless connection over which the HAN relay device communicates with a second HAN relay device in a first sub-mesh network of HAN relay devices. The HAN device also includes a second set of radios, each of the second set of radios being coupled to a beam-steering antenna and each of the second set of radios establishing a second PtP wireless connection over which the HAN relay device communicates with at least one of a plurality of HAN devices in a second sub-mesh network in the WMN.
    Type: Grant
    Filed: September 8, 2016
    Date of Patent: October 15, 2019
    Assignee: Amazon Technologies, Inc.
    Inventors: Jin Dong Kim, Sang Eun Lee, In Chul Hyun, Cheol Su Kim, Subram Narasimhan, Varadarajan Gopalakrishnan, Omar Fawazhashim Zakaria
  • Patent number: 10440584
    Abstract: Technology for radios that support single channel, multi-channel, SISO, MIMO, and beamforming communications at millimeter wave frequencies using WLAN transceivers or other IF transceivers. One radio includes a first transceiver configured to generate a first RF signal in a first frequency range; a second transceiver configured to generate a third RF signal in a mm-wave frequency range, the second transceiver is configured to couple to a multi-element antenna for beamforming operations; and conversion circuitry coupled to an output of the first transceiver and an input of the second transceiver. The conversion circuitry is configured to receive the first RF signal from the first transceiver and convert the first RF signal in the first frequency range to a second RF signal in the mm-wave frequency range; and receive the third RF signal from the second transceiver and convert the third RF signal to a fourth RF signal in the first frequency range.
    Type: Grant
    Filed: September 25, 2017
    Date of Patent: October 8, 2019
    Assignee: Amazon Technologies, Inc.
    Inventors: Nathan Labadie, Cheol Su Kim
  • Patent number: 10263667
    Abstract: Network hardware devices organized in a wireless mesh network (WMN) in which one network hardware devices includes a first wireless radio and a power line communications (PLC) radio coupled to a processing device. The processing device communicates, using the first wireless radio, first data with a second mesh network device over a wireless link between the first wireless radio and a first wireless radio of the second mesh network device. The processing device also communicates, via the power distribution network via the PLC radio, second data with the second mesh network device over a PLC link between the first PLC radio and a first PLC radio of the second mesh network device. The first data and the second data may be redundant data. The first data may be content data and second data may be control data. The first and second data may be subsets of the same digital content.
    Type: Grant
    Filed: August 4, 2016
    Date of Patent: April 16, 2019
    Assignee: Amazon Technologies, Inc.
    Inventors: Omar Fawazhashim Zakaria, Cheol Su Kim
  • Patent number: 10193236
    Abstract: Network hardware devices organized in a Wireless mesh network (WMN) in which the network hardware devices cooperate in distribution of content files to client consumption devices without Internet connectivity are described. One mesh network device includes a housing with a first sector defined by a first recessed region between a first reflective wall, a second reflective wall, and a third reflective wall, and a second sector defined by a second recessed region between a fourth reflective wall, a fifth reflective wall, and a sixth reflective wall. A first antenna, such as a phased array dipole antenna, is disposed inside the first recessed region. A first radio, which is coupled to the first antenna, causes the first antenna to radiate electromagnetic energy in a first frequency range and the first, the second, and the third reflective walls collectively reflect the electromagnetic energy, radiated by the first antenna, in a first direction away from the housing.
    Type: Grant
    Filed: June 22, 2016
    Date of Patent: January 29, 2019
    Assignee: Amazon Technologies, Inc.
    Inventors: Tzung-I Lee, Cheol Su Kim, In Chul Hyun
  • Patent number: 10075198
    Abstract: Radio frequency (RF) front-end circuitry and methods of operating the same are described. One apparatus includes multiple antennas and a RF front-end circuitry. The RF front-end circuitry includes a first diplexer, a second diplexer, a third diplexer, a fourth diplexer, and a switch. A first transceiver is coupled to a first antenna via the first diplexer and the second diplexer. The third receiver is coupled to the first antenna via the first diplexer. The second transceiver is selectively coupled to a second antenna via the third diplexer, the switch, and the fourth diplexer when the switch is set to the first mode in response to the control signal from a processing component. The first transceiver is selectively coupled to the second antenna via the switch and the third diplexer when the switch is set to the first mode in response to the control signal from the processing component.
    Type: Grant
    Filed: March 30, 2016
    Date of Patent: September 11, 2018
    Assignee: Amazon Technologies, Inc.
    Inventors: Tzung-I Lee, Varadarajan Gopalakrishnan, Cheol Su Kim, In Chul Hyun
  • Patent number: 9991914
    Abstract: Technology for a bi-directional radio frequency front-end (RFFE) architecture with high selectivity performance is described. One RFFE has a first mixer that receives a LO signal from the LO circuit and a transmit (TX) signal, having a first frequency, from a transmitter and produces a down-converted TX signal for channel bandwidth filtering, the TX signal having a second frequency that is lower than the first frequency. A programmable filter circuit, in response to a selection signal, filters the down-converted TX signal according to a selected channel bandwidth. The second mixer receives the LO signal from the LO circuit and a channel-filtered TX signal from the programmable filter circuit and produces an up-converted TX signal having the first frequency. The power amplifier amplifies the up-converted TX signal to produce an output TX signal to cause an antenna to radiate electromagnetic energy in the selected channel bandwidth.
    Type: Grant
    Filed: May 15, 2017
    Date of Patent: June 5, 2018
    Assignee: Amazon Technologies, Inc.
    Inventors: Tzung-I Lee, Omar Fawazhashim Zakaria, Cheol Su Kim, Varadarajan Gopalakrishnan, In Chul Hyun
  • Patent number: 9900880
    Abstract: Network hardware devices organized in a wireless mesh network (WMN) in which one network hardware devices includes three radios, two of which operate with a frequency separation less than 100 MHz. A first network hardware device communicates with a second network hardware device when not serving data to a client device. When serving data to a client device, the first network hardware device communicates wireless wide area network (WWAN) data to a WWAN network through a third network hardware device in the WMN that has its own WWAN connection to create spatial separation for simultaneous communication.
    Type: Grant
    Filed: May 13, 2016
    Date of Patent: February 20, 2018
    Assignee: Amazon Technologies, Inc.
    Inventors: Omar Fawazhashim Zakaria, Cheol Su Kim, In Chul Hyun, Varadarajan Gopalakrishnan