Method and system for locating sensor node in sensor network using distance determining algorithm
First Claim
1. A position locating system for a sensor network, comprising:
- a plurality of reference nodes, each reference node of said plurality of reference nodes having self-positional information regarding a respective position thereof; and
a sensor node having a position location table,wherein each reference node comprises;
a control unit for generating, in response to a location information request signal, a location information; and
a radio frequency (RF) communication unit for receiving a location information request signal and for forwarding the received location information request signal to the control unit, controlling transmission power, and sending the generated location information in return,wherein the sensor node comprises;
a control unit for generating a coordinate request signal, analyzing transmit power levels extracted from location information from reference nodes, and for calculating coordinates of a position of the sensor node using the position location table; and
an RF communication unit for transmitting the coordinate request signal, and for receiving location information and forwarding the location information to the control unit,wherein the position location table is formed by providing a grid of a preset number of vertical and horizontal lines corresponding to a square area defined by an arrangement of the plurality of reference nodes;
wherein measured distances from each intersection point in the grid to each of the reference nodes, respectively correspond to transmit power levels;
wherein intersection points sorted according to transmit power level patterns are arranged into sorted groups in which each particular group has a middle point of those intersection points belonging to the particular group; and
error calculating means for calculating errors for all groups to determine whether a largest group error is within a desired error boundary.
1 Assignment
0 Petitions
Accused Products
Abstract
For a sensor network having reference nodes and sensor nodes, A method and apparatus using a distance determining algorithm for a sensor network having reference nodes and sensor nodes. A distance determining algorithm is executed to determine an adequate distance between reference nodes within a preset error range, and a position location table is created. A sensor node sends a location information request to reference nodes, receives the position location table and location information from the reference nodes, and computes the coordinates of its position. Alternatively, without requesting transmission of the position location table, the sensor node may receive calculated coordinates of its position directly from a reference node.
-
Citations
23 Claims
-
1. A position locating system for a sensor network, comprising:
-
a plurality of reference nodes, each reference node of said plurality of reference nodes having self-positional information regarding a respective position thereof; and a sensor node having a position location table, wherein each reference node comprises; a control unit for generating, in response to a location information request signal, a location information; and a radio frequency (RF) communication unit for receiving a location information request signal and for forwarding the received location information request signal to the control unit, controlling transmission power, and sending the generated location information in return, wherein the sensor node comprises; a control unit for generating a coordinate request signal, analyzing transmit power levels extracted from location information from reference nodes, and for calculating coordinates of a position of the sensor node using the position location table; and an RF communication unit for transmitting the coordinate request signal, and for receiving location information and forwarding the location information to the control unit, wherein the position location table is formed by providing a grid of a preset number of vertical and horizontal lines corresponding to a square area defined by an arrangement of the plurality of reference nodes; wherein measured distances from each intersection point in the grid to each of the reference nodes, respectively correspond to transmit power levels; wherein intersection points sorted according to transmit power level patterns are arranged into sorted groups in which each particular group has a middle point of those intersection points belonging to the particular group; and error calculating means for calculating errors for all groups to determine whether a largest group error is within a desired error boundary. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A position locating method for a sensor network having reference nodes and at least one sensor node, comprising:
-
transmitting, by the sensor node, a location information request signal; transmitting, by each of neighbor reference nodes in response to reception of the location information request signal, a position location table, information on a node distance from each reference node to the sensor node and maximum transmission distances by transmit power levels, and transmitting transmit power data and absolute coordinate data while valving transmission power; and calculating, by the sensor node, a location of the sensor node using the position location table and transmit power levels of the reference nodes, wherein the position location table is created using a procedure comprising; forming a grid of a preset number of vertical and horizontal lines corresponding to a square area defined by plural reference nodes; measuring distances from each intersection point in the grid to the reference nodes, and finding transmit power levels corresponding to the measured distances; sorting intersection points according to transmit power level patterns into groups, and finding, for each group, a middle point of those intersection points belonging to the group; and calculating errors for all groups, and checking whether the largest group error is within a desired error bound. - View Dependent Claims (11, 12, 13)
-
-
14. A position locating system for a sensor network, comprising:
-
a plurality of reference nodes, each reference node including self-positional information of a position thereof and having a position location table; and a sensor node, wherein each reference node comprises; a control unit for generating, in response to a location information request signal from the sensor node, location information, and for calculating, in response to a coordinate request signal from the sensor node, coordinates of a position of the sensor node; and a radio frequency (RF) communication unit for receiving a location information request signal or a coordinate request signal from the sensor node and forwarding the received signal to the control unit, controlling transmission power, for sending the generated location information in return for the location information request signal, and for sending the coordinates of the position of the sensor node in return for the coordinate request signal, wherein the sensor node comprises; a control unit for generating a location information signal or a coordinate request signal; and an RF communication unit for transmitting the location information signal or coordinate request signal, and for receiving location information and forwarding the location information to the control unit, wherein the position location table is formed by providing a grid of a preset number of vertical and horizontal lines corresponding to a square area defined by an arrangement of plural reference nodes; wherein measured distances from each intersection point in the grid to each of the reference nodes, respectively correspond to transmit power levels; wherein intersection points are sorted according to transmit power level patterns and are arranged into groups, in which each particular group has a middle point of those intersection points belonging to the particular group; and error calculating means for calculating errors for all groups to determine whether a largest group error is within a desired error boundary. - View Dependent Claims (15, 16, 17, 18, 19, 20)
-
-
21. A position locating method for a sensor network having reference nodes and at least one sensor node, comprising:
-
transmitting, by the sensor nod;
a location information request signal;transmitting, by each of neighbor reference nodes in response to reception of the location information request signal, information on a node distance from each reference node to the sensor node and maximum transmission distances by transmit power levels, and transmitting transmit power data and absolute coordinate data while varying transmission power transmitting, by the sensor node, a coordinate request signal carrying information on transmit power levels of the reference nodes; and calculating, by a reference node receiving the coordinate request signal, a location of the sensor node using the transmit power levels of the reference nodes and a position location table, and sending coordinates of the calculated location, wherein the position location table is created using a procedure comprising; forming a grid of a preset number of vertical and horizontal lines corresponding to a square area defined by plural reference nodes; measuring distances from each intersection point in the grid to the reference nodes, and finding transmit power levels corresponding to the measured distances; sorting intersection points by according to transmit power level patterns into groups, and finding, for each group, a middle point of those intersection points belonging to the group; and calculating errors for all groups, and checking whether the largest error is within a desired error bound. - View Dependent Claims (22, 23)
-
Specification