Method and system for locating sensor node in sensor network using transmit power control
First Claim
1. A position locating system for a sensor network, comprising:
- a plurality of reference nodes, each reference node including location information of its own location; and
a sensor node for computing a location thereof on a basis of respective location information of each reference node of said plurality of reference nodes,wherein each reference node of said plurality of reference nodes comprises;
a control section for generating a location information signal including a transmit power level and said location information of its own location upon reception of a location information request signal; and
a radio frequency (RF) section for forwarding the received location information request signal to the control section, and for controlling transmission power according to the transmit power level of the control section to send the generated location information signal,wherein said sensor node comprises;
a control unit for computing a location of the sensor node and an associated error of the computed location on the basis of one or more location information signals received from neighbor reference nodes;
an RF unit for sending said location information request signal to one or more of said plurality of reference nodes, and for receiving location information signals and forwarding the same to the control unit; and
a storage unit storing the location information signals received from multiple neighbor reference nodes;
wherein each reference node transmits location signals at a plurality of power levels, with each power level corresponding to a known transmission range; and
the control unit of the sensor node computes a position and associated error range using only a location information signal from each reference node having a lowest transmit power level among the plurality of power levels that permits position and error range computation for that reference node.
2 Assignments
0 Petitions
Accused Products
Abstract
A method and apparatus for a sensor network having a plurality of reference nodes and a sensor node that enables the sensor node to compute a relative position through transmission range control and position mapping. In transmission range control, each reference node sends location information signals to the sensor node while varying transmission power. In position mapping, the sensor node forms a grid of vertical and horizontal lines corresponding to a square area defined by the neighboring reference nodes, extracts coordinates of intersections in the grid belonging to a shared region between areas covered by location information signals of various transmit power levels from the neighboring reference nodes, and sets the position of the sensor node to the middle points of the extracted coordinates. Each reference node sends a location information signal when a random backoff time expires after reception of a location information request signal.
-
Citations
22 Claims
-
1. A position locating system for a sensor network, comprising:
-
a plurality of reference nodes, each reference node including location information of its own location; and a sensor node for computing a location thereof on a basis of respective location information of each reference node of said plurality of reference nodes, wherein each reference node of said plurality of reference nodes comprises; a control section for generating a location information signal including a transmit power level and said location information of its own location upon reception of a location information request signal; and a radio frequency (RF) section for forwarding the received location information request signal to the control section, and for controlling transmission power according to the transmit power level of the control section to send the generated location information signal, wherein said sensor node comprises; a control unit for computing a location of the sensor node and an associated error of the computed location on the basis of one or more location information signals received from neighbor reference nodes; an RF unit for sending said location information request signal to one or more of said plurality of reference nodes, and for receiving location information signals and forwarding the same to the control unit; and a storage unit storing the location information signals received from multiple neighbor reference nodes; wherein each reference node transmits location signals at a plurality of power levels, with each power level corresponding to a known transmission range; and the control unit of the sensor node computes a position and associated error range using only a location information signal from each reference node having a lowest transmit power level among the plurality of power levels that permits position and error range computation for that reference node. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. A position locating method for a sensor network having a plurality of reference nodes and a sensor node, comprising:
-
transmitting, by the sensor node, a location information request signal; transmitting, by neighbor reference nodes in response to reception of the location information request signal from the sensor node, location information signals to the sensor node while varying transmission power such that the location information signals are transmitted by each of the neighbor reference nodes at a plurality of power levels, with each power level corresponding to a known transmission range; and computing, by the sensor node, a location of the sensor node and associated error range of the computed location after reception and analysis of the location information signals, the location and associated error range being computed using only a location information signal from each neighbor reference node having a lowest transmit power level among the plurality of power levels for that reference node that permits position and error range computation. - View Dependent Claims (14, 15, 16, 17, 18, 19, 20, 21, 22)
-
Specification