Abstract:
본 발명은 USN(Ubiquitous Sensor Network) 기반의 MAC에서 다중채널 액세스를 제어하는 장치 및 방법에 관한 것이다. 이를 위해 본 발명의 다중채널액세스제어장치는 송신센서노드에서 데이터채널 중 가용할 수 있는 적어도 하나 이상의 가용채널을 검색하는 채널검색부; 송신센서노드는 컨트롤채널센싱 및 백오프를 통해 상기 컨트롤채널을 선점한 후 프리앰블을 컨트롤 채널에 주기적으로 방송하는 컨트롤채널선점부;및 수신센서노드는 수신한 프리앰블을 기초로 송신센서노드가 가용할 수 있는 가용채널을 파악하고 그 중 수신센서노드에서 가용할 수 있는 채널을 선택하여 그 정보를 송신센서노드에 전송하는 가용채널교환부;를 포함한다. 채널검색, 채널 협상
Abstract:
A media access control device of a medium access control method in a sensor network reducing delay generated between a hop and a sensor node are provided to process data quickly by using a check interval of short length. A first node performs an LPL(Low Power Listening) which is the check interval which is most short among the usable check interval(S510). A first node receiving the downward traffic information determines the check interval by summing the traffic volume which periodically reports to the sink node by summing upward traffic and downward traffic which receives from its own lower nodes(S525). The first node transmits the upward traffic binding update message by using the long preamble of the type '2 fitted to the check interval of the node having the most small traffic(S540).
Abstract:
A method for extending an operation time of a wireless sensor network is provided to lengthen an operation time of an overall sensor network system for the same power. A preliminary value of a BI(Beacon Interval) is calculated(S501) and compared with a maximum BI(S502). If the preliminary value of the BI is smaller than the maximum BI, a new BI is calculated by adding a value obtained by multiplying a weight value to the maximum BI(S503). In order to inform other nodes about the calculated new BI through a packet, a reserved field of a super-frame specification field is set as 1. If the preliminary value of the BI is larger than the maximum BI, the preliminary value of the BI is used as a new BI(S504).
Abstract:
A device and a method for managing a buffer and processing a received interrupt between a MAC hardware and software processor are provided to lower complexity for buffer management for the received interrupt continuously generated between the MAC hardware and software processor, and reduce loss such as disuse of a received frame. An address decoder(110) decodes/connects an internal hardware address of the MAC software processor(20) to a block when a hardware interrupt is generated by receiving the frame. An interrupt state register(140) forms and provides a bit map by a frame storing state of each buffer(160). An interrupt access register(130) provides the MAC hardware processor(10) with the information for controlling access to the MAC hardware processor when the interrupt state register is updated. A frame length register(120) forms the bitmap by using length information of the frame stored in each buffer and provides the bitmap when the MAC software processor reads the frame. A hardware interrupt controller(150) stores the frame to the empty buffer based on the information received from the interrupt state register.
Abstract:
PURPOSE: A method for collecting area charge on the Internet and a method for authenticating a user therefor are provided to realize regionally dispersed charge collecting. CONSTITUTION: An Internet connected user requests an Internet contents provider to a charge collecting device, MF router(S1). The charge collecting device searches for user data through a temporary user data table(S2). If the user data does not exist, the charge collecting device searches for user data at an authentication/billing server(S4-S5). If the user data do not exist, the charge collecting device sends guide information and a register form to a user(S7). The user registers user's data at the authentication/billing server and the temporary user data table(S8). The user receives a response to the registration and uses wanted information(S9-S11).
Abstract:
Provided is a system for constructing an irrigation model using a plurality of flow measurement sensor nodes. The system for constructing an irrigation model includes a plurality of sensor nodes measuring the flow of each river and a material collection device constructing an irrigation model of a river based on the flow measured by each sensor node. Each of the sensor nodes includes a first sensor node measuring the flow of the water flowing into the river; a second sensor node measuring the flow of the water flowing out from the river; and a third sensor node measuring the flow of the water flowing into a main stream of the river from a branch.