Location system for street light monitoring

A computer-readable medium having stored thereon computer-readable instructions that, when run on a computer, are configured for performing the steps of any of the methods of:

• providing each street lamp of a network of numerous street lamps with a node controller and a ballast controller, the node controllers of the street lamps communicating to each other using wireless devices to build up a mesh network;
• providing a number of cluster controllers, the cluster controllers controlling a subset of the street lamps in the network and being equipped with a transceiver, the transceiver communicating to the mesh network;
• providing a cluster head, the cluster head controlling the network of street light and being coupled to the number of cluster controllers based on an external network;
• providing a small fraction of the street lamps in the network and less than 30% of the street lamps in the network as anchor street lamps with their absolute and relative coordinates;
• determining the average hop length in any minimum length path between two anchor street lamps;
• determining for each street lamp in the network not being provided with their absolute and relative coordinates as blind street lamps the distance of the blind street lamp to the nearest anchor street lamps based on path loss evaluating received signal strength indication, RSSI, between the street lamps in the path to the nearest anchor street lamps, assigning the measured path loss values to pre-determined distance categories, assigning the distance categories to hop link values and multiplying the hop link values with the average hop length in the respective path;
• inferring for each blind street lamp in the network a coarse position using multi-lateration based on the determined distances to the nearest anchor street lamps for that blind street lamp;
• and
• adjusting the coarse position by selecting for each blind street lamp coarse position the closest possible real position and if no closest possible real position is present classify the blind street lamp as not positioned.

A computer-implemented street light monitoring system providing automated position estimation capabilities for all street lights being present in the street light system and thereby enabling efficient management of street lamps, the system comprising:

• network of numerous street lamps, each street lamp equipped with a node controller and a ballast controller, the node controllers of the street lamps communicating to each other using wireless devices to build up a mesh network;
• cluster controllers, each of the number of cluster controllers controlling a subset of the street lamps in the network and being equipped with a transceiver, the transceiver communicating to the mesh network;
• cluster head, the cluster head controlling the network of street light and being coupled to the number of cluster controllers based on an external network;
• anchor street lamps as a small fraction of the street lamps in the network and less than 30% of the street lamps in the network provided with their absolute and relative coordinates;
• means for determining the average hop length in any minimum length path between two anchor street lamps;
• blind street lamps as each street lamp in the network not being provided with their absolute and relative coordinates;
• means for determining the distance of a blind street lamp to the nearest anchor street lamps based on path loss evaluating received signal strength indication, RSSI, between the street lamps in the path to the nearest anchor street lamps, assigning the measured path loss values to pre-determined distance categories, assigning the distance categories to hop link values and multiplying the hop link values with the average hop length in the respective path;
• means for inferring for each blind street lamp in the network a coarse position using multi-lateration based on the determined distances to the nearest anchor street lamps for that blind street lamp;
• and
• means for adjusting the coarse position by selecting for each blind street lamp coarse position the closest possible real position and if no closest possible real position is present classify the blind street lamp as not positioned.

A method for providing position estimation for street lights in a street light system, the method comprising:

• for a small fraction of the street lights in the street light system providing absolute and relative coordinates, with each such street being referred to as an anchor street light;
• determining an average hop length in any minimum length path between two anchor street lights;
• determining for each street light not being provided with absolute and relative coordinates, with each such street light being referred to as a blind street light, the distance of the blind street light to the nearest anchor street light based on a received signal strength indication between the street lights in the path to the nearest anchor street light;
• assigning a measured path loss values to pre-determined distance categories;
• assigning distance categories to hop link values and multiplying the hop link values with the average hop length in the respective path;
• inferring for each blind street light a coarse position using multi-lateration based on the determined distances to the nearest anchor street lamps for that blind street lamp;
• and
• adjusting the coarse position of each blind street light by selecting a nearest possible real position.

A street light monitoring system, comprising:

• a network of street lamps, each street lamp including a node controller and the node controllers of the street lamps communicating with each to form a mesh network;
• a plurality of cluster controllers, each cluster controller communicating through the mesh network to control a subset of the street lamps in the network;
• a cluster head operable to control the network of street lamps and being coupled to the cluster controllers through an external network;
• a plurality of anchor street lamps wherein the plurality is a small fraction of the total number of street lamps in the network;
• a plurality of blind street lamps corresponding to the remaining street lamps in the network;
• control circuitry operable to determine the position of the blind street lamps through link quantization, multi-hop distance estimation, and street lamp position adjustment.