Ajou University Industry-academic Cooperation Foundation

Other

Agency for Defense Development

Jae Sung Lim

Kyu Man Lee

Hong Jun Noh

Jung Bin Kim

Kyung Woo Kim

Jin Seok Lee

Hyung Won Park

Soon Jin Choi

Eui Hyeok Kwon

Ho Ki Baek

Jae Hyun Ham

Ki Hyoung Kim

Jun Woo Jung

Provided is a method and apparatus for selecting an airborne position reference node. A weight center coordinate of the repeaters is calculated by using position coordinates of repeaters, a plane having a vector connecting the weight center coordinate and a position coordinate of a user as a normal vector is determined, and the position coordinates of the repeaters are orthographically projected onto the plane. A certain number of repeaters located farthest from the weight center coordinate of the repeaters are selected to be airborne position reference nodes, on the basis of the orthographically projected coordinates of the repeaters and the weight center coordinate.

Apparatus and method of selecting airborne position reference node

A time division multiple access frame structure includes a signal transmission section allocated for transmitting reference signals from a plurality of ground reference stations; a relay section for relaying the transmitted reference signals by a plurality of aeronautical satellite relay stations selected by a central station; and a data transmission section for data transmission of the central station, the plurality of ground reference stations, or the plurality of aeronautical satellite relay stations, wherein the signal transmission section, the relay section, and the data transmission section are time division multiplexed with each other.

Positioning method based on time division multiple access, positioning system, and frame structure used therein

The present invention generally relates to a random access method and apparatus based on analog network coding for a satellite network and, more particularly, to technology that combines analog network coding with random access, thus guaranteeing high channel usage efficiency upon utilizing the technology for a satellite positioning/communications convergence system. For this, a random access apparatus based on analog network coding for a satellite network according to an embodiment of the present invention includes a received signal determination unit, a data packet transmission unit, a reserved slot decision unit, a response message reception unit, and a data packet decoding unit.

Random access method and apparatus based on analog network coding for two-way relay channel

Disclosed are an apparatus and method for communicating with satellite based on analog network coding. A method for satellite communication, according to one embodiment of the present invention, is a method for satellite communication of a satellite terminal and comprises the steps of: receiving transmission data from a feeder that directly transmits the transmission data to a satellite; receiving a superposed signal, in which the transmission data and reception data corresponding to the transmission data have been analog network coded, from the satellite; and extracting the reception data from the superposed signal using the superposed signal and the received transmission data.

Apparatus and method for communicating with satellite based on analog network coding

An apparatus and method for predicting mobility based on relative mobile characteristics are disclosed herein. The method of predicting mobility based on relative mobile characteristics includes detecting, by each of a plurality of sensor nodes of a sensor network including the plurality of sensor nodes, a change in relative location with respect to an observed node; recording, by the each of the plurality of sensor nodes, information about the detected change in relative location; generating, by the each of the plurality of sensor nodes, a mathematical model for a possibility of approach of the observed node with respect to the each of the plurality of sensor nodes using the recorded relative location change information; and predicting probabilistically, by the each of the plurality of sensor nodes, whether the observed node will approach the each of the plurality of sensor nodes using the mathematical model.

Method and apparatus for predicting mobility based on relative mobile characteristics

The present invention relates to methods and apparatuses for establishing a routing path in a multi-hop network. The methods comprises (a) transmitting a notification message associated with communication problem to neighboring nodes, (b) deriving approaching characteristics of a communication problem-causing element from the notification message, and (c) establishing a routing path based on the approaching characteristics of the communication problem-causing element. With the methods and apparatuses, it is possible to determine a path that is expected to experience a communication problem based on the approaching characteristics of a communication problem-causing element and to adaptively establish a reliable routing path.

Method and apparatus for establishing routing path in multi-hop network

An OFDM-based multiple access method and a communication device controlling the same are provided. The OFDM-based multiple access method includes transmitting a predetermined synchronization control signal to many and unspecified terminals, and receiving a test message from the terminals in response to the synchronization control signal; classifying the terminals that receive the test message in a first unit time from a predetermined reference time after the transmission of the synchronization control signal into a first group, and classifying the terminals that receive the test message in a certain n-th unit time from the reference time into an n-th group; allocating use permission time of sub-channels to the groups; and the terminals transmitting/receiving data through partial occupation of the sub-channels and symbols at a time allocated to the corresponding groups.

OFDM-based multiple access method and communication device controlling the same

An orthogonal code including an orthogonal code set capable of a plurality of parallel processes through a cyclic shift method is provided. Moreover, a multiple access method of effectively using a new cyclic orthogonal complementary code (cyclic-OC) is provided.

Method and apparatus for orthogonal frequency division multiplex

Disclosed are a method and an apparatus for communicating with seven or more terminals in a Bluetooth system of a Wireless Personal Area Network (W-PAN). In the method and apparatus, a sniff mode allowing slaves to be in a sleep state for a Sniff Interval Time (SIT) is converted into an active mode for a service such that a master can efficiently communicate with seven or more slaves using conventional seven Active Member Addresses (AM_ADDR).

Growing community of inventors

Suwon-si, South Korea

Jae Sung Lim