Abstract:
PURPOSE: A sensing and transmission parameter determination method in a recognition wireless network is provided to find out the length of a sensing period and a data transmission period which increase the throughput of a secondary user. CONSTITUTION: A collision probability between a first user and a secondary user is calculated(S103). When the collision probability is satisfied, the sensing period and the data transmission period for increasing the throughput of the first user are determined(S104). A steady state probability using a second-state Markov chain model is calculated. The collision probability between the first and the secondary user is calculated from a normal state probability. [Reference numerals] (AA) Start; (BB) End; (S101) Generate the state transition probability of each state using a second-state Markov chain model; (S102) Generate a normal state matrix; (S103) Generate a collision probability; (S104) Calculate the minimum M(sensing parameter) and the maximum T(transmission parameter) using that the sum of a success probability and a collision probability becomes 1
Abstract:
PURPOSE: A polling list recognizing method and recording medium thereof which uses the orthogonal signal of a wireless LAN are provided to enable a terminal to perform a polling request to a base station by using an orthogonal signal. CONSTITUTION: A base station(10) transmits first and second orthogonal codes(S10). Each terminal receives the first and second orthogonal codes. Each terminal transmits the first and second orthogonal codes to the base station(S30). The base station determines whether the terminal performs polling according to received orthogonal code(S20).
Abstract:
PURPOSE: A 3-hop ahead path reservation method in a wireless sensor network is provided to ensure, in advance, transmission for the traffic having higher priority through a path reservation technique. CONSTITUTION: A wireless sensor network enlarges the space between nodes as 3-hole in order to enable reservation and transmission at the same time. The wireless sensor network performs the reservation and data transmission at the same time for two nodes that are distanced over 3-hops. The wireless sensor network is configured with the data transmission after completing the reservation up to a sync node(31).
Abstract:
Disclosed is a polling list management method using orthogonal signaling in a wireless LAN including a plurality of terminals and a base station, the method comprising: a first step where the base station transmits a first and a second orthogonal code to the respective terminals, the orthogonal codes being unique for each terminal and "bit-wise inverse" of each other; a second step where the respective terminals having received the first and second orthogonal codes transmit one of the first and second orthogonal codes to the base station to request polling; and a third step where the base station determines whether the corresponding terminal should be polled, based on the received orthogonal code.
Abstract:
본원발명은 센서 네트워크의 트리구조를 저비용으로 구축할 수 있도록 하는 센서 네트워크 트리구조 구축방법에 관한 것으로서, 각 노드들이 싱크로부터의 홉 수와 생성될 트리 구조 안에서의 자신의 하위 계층에 위치되는 자신의 자식 노드(children nodes) 수에 기반하여 자신의 부모노드점수를 계산하고, 상기 센서 네트워크의 싱크 노드가 라우팅 구조의 형성을 명령하는 라우팅 초기화 메시지를 전체 센서 네트워크로 플러딩(flooding)하는 초기화과정; 상기 각각의 노드들이 초기화 메시지를 수신한 후 자신의 싱크로부터의 홉 수에 비례하는 대기시간만큼 기다리는 대기과정; 인접 노드들 중 최고 부모노드점수를 가지는 노드를 자신의 부모노드로 선정하는 부모노드선정과정;으로 이루어지며, 상기 센서 네트워크 트리 구조 구축 방법의 처리과정들이 각 센서 노드에서 개별적으로 이루어져 모든 센서 노드가 자신의 부모노드를 설정함으로써 전체 센서 네트워크의 트리 구조가 형성되도록 하는 것을 특징으로 한다. 센서 네트워크, 트리구조, 간섭제거, 싸이클제거, 부모노드점수, 부모노드 선정 우선순위
Abstract:
본 발명은 인지 무선 네트워크에서의 감지 및 전송 매개변수 결정 방법에 관한 것이다. 본 발명은, 1차 사용자(이하, PU)와 2차 사용자(이하, SU)로 구성된 인지 무선 네트워크 환경에서의 감지 및 전송 매개변수 결정 방법에 있어서, 상기 PU와 상기 SU 간의 충돌 확률을 연산하는 단계와, 상기 충돌 확률을 만족시키면서, 상기 SU의 쓰루풋을 최고로 향상시키기 위한 감지 기간 및 데이터 전송 기간을 결정하는 단계를 포함한다. 이에 의해, 인지 무선 네트워크에서 PU가 요구하는 충돌 수준(probability of collision)을 만족하면서 최고로 높은 쓰루풋(throughput)을 가지는 감지 기간과 데이터 전송 기간의 길이를 제공할 수 있다.
Abstract:
본발명에따라센서네트워크에서네트워크내부데이터집적(in-network data aggregation) 기법을사용할때 각센서노드가설정하는전송전 대기시간 (waiting time before transmitting aggregated data)을효율적으로설정하는방법이개시된다. 본발명은수집할데이터가압축률은낮으나, 하나의패킷에여러개를담아전송할수 있고, 한패킷에담을수 있는데이터개수는패킷크기한계등의이유로제한되어있는환경을가정하여, 노드에현재축적되어있는데이터개수에따라다른대기시간제한을설정한다. 본발명에서제시하는대기시간조절방법으로데이터수집응용에서에너지효율성을높이고통신지연시간을낮출수 있다.
Abstract:
PURPOSE: A waiting time controlling method in consideration with packet size in a sensor network is provided to increase the performance of a data aggregation method in case data is compressed. CONSTITUTION: An initialization message is transmitted from a sink node to a sensor node. Data which is collected by the sensor node is transmitted to the sink node. The initialization message is received in order to control waiting time according to the number of data. The waiting time is controlled by Ti=MAX( hXg/q/cX(i-1)+g/q, 0 ).
Abstract:
PURPOSE: A method for constructing a sensor network tree structure is provided to require minimum hardware and information, thereby constructing the tree structure of the sensor network at a lower cost. CONSTITUTION: When changing a sensor network, each node of the sensor network calculates a parent node score and parent node selection priority. According to the parent node selection priority, each node collects a parent node score from neighboring nodes(S210). The node transmits a parent node selection message to a node with a top parent node score(S220). A node which receives the message transmit a parent node confirmation message to the node(S240). The nodes register the opponent as a child node and a parent node(S253,S255).