Mobile communication and localization device

• US 9,268,007 B2
• Filed: 06/12/2009
• Issued: 02/23/2016
• Est. Priority Date: 06/12/2008
• Status: Active Grant

• Current Assignee: Sisvel Technology S.r.l. (Fineur International S.A.)
• Original Assignee: Sisvel Technology S.r.l. (Fineur International S.A.)
• Inventors: Malnati, Giovanni, Ruo Rui, Paola, Caputo, Gianfranco, Barberis, Claudia
• Primary Examiner(s): Mills, Donald
• Assistant Examiner(s): Baron, Henry
• Application Number:
  US12/997,572
• Publication Number:
  US 20110134781A1
• Time in Patent Office: 2,447 Days
• Field of Search: 370/252
• US Class Current: 1/1
• CPC Class Codes: G01S 11/06 using intensity measurements
• CPC Class Codes: G01S 5/0072 Transmission between mobile stations, e.g. anti-collision systems
• CPC Class Codes: G01S 5/0289 of multiple transceivers, e.g. in ad hoc networks
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

A mobile communication and localization device cooperating with a plurality of mobile network devices includes a processing unit; a data structure containing a plurality of entries, each entry containing information about a corresponding mobile network device and a corresponding time stamp; a unit for sending data packets at respective transmission instants, each data packet containing position data indicating the position of corresponding mobile network devices; a unit for receiving data packets sent by sender mobile devices belonging to the plurality of mobile network devices; and a unit for determining the relative position of corresponding mobile network devices based on position data contained in the data packets.

Claims

1. A mobile communication and localization device configured for cooperating with a plurality of mobile network devices, the device comprising:

a processing unit;

a data structure adapted to contain a plurality of entries, each entry containing information about a mobile network device belonging to said plurality of mobile network devices and a corresponding time stamp;

means for sending data packets at successive instants of transmission to the plurality of mobile network devices, each data packet containing position data indicating positions of said mobile network devices;

means for receiving data packets sent by said mobile network devices belonging to said plurality of mobile network devices, wherein information in the received data packet is incorporated into the entries in the data structure;

means for managing the information contained in said data structure with a local clock, and managing the information contained in each said data packet with a time interval elapsed between the time instant represented by the time stamp associated with a pertaining piece of information, as stored in said data structure of said sending mobile network device, and the instant of transmission of said data packet, according to the local clock of said sending mobile network device;

means for determining, based on said position data contained in said data packets, the relative positions of said mobile network devices and further wherein said data packets comprise indications of an alarm status of at least one other mobile network device belonging to the plurality of mobile network devices; and

means for signaling an alarm status,

wherein said processing unit comprises means for calculating estimated distances from said mobile network devices, said estimated distances being calculated at successive calculation instants,

wherein said data structure is configured in a manner such that said information about a corresponding mobile network device contained in each entry comprises;

the estimated distance from said mobile network device, the time stamp associated thereto indicating the instant of reception of the data packet containing the power data used for calculating said estimated distance;

a shortest path length, in the case of a first mobile network device belonging to a succession of mobile network devices and indirectly reachable through said succession, wherein the time stamp associated to said information indicating an instant of generation of a data packet by said first mobile network device

wherein said means for determining said relative position of said mobile network devices comprise;

means for determining the instant of reception of each data packet;

means for calculating, for each mobile network device identified by a position data contained in said data packet, a time stamp equal to the difference between the instant of reception and the time stamp associated to said position data;

means for verifying if said data structure comprises an entry pertaining to said identified mobile network device;

means for generating a new entry, which are activated in the event that there is no entry for said identified mobile network device, and which associate the shortest path length increased by one unit and said time stamp with said identified mobile network device; and

means for comparing the calculated time stamp with a stored time stamp, which are activated in the event that said entry for said identified mobile network device already exists and contains said stored time stamp, and for updating said entry if said calculated time stamp is subsequent to said stored time stamp, and

wherein said comparing means will also update said entry if said calculated time stamp matches said stored time stamp and said data packet indicates a shortest path which is shorter than the shortest path length contained in said entry.

2. The mobile communication and localization device according to claim 1, wherein each data packet contains a power datum indicating its emission power (P_e), and said estimated distances are calculated based on the power data contained in said data packets.

3. The mobile communication and localization device according to claim 2, wherein said estimated distances are calculated by determining the reception power (P_r) associated with a received data packet and by calculating a power attenuation (Δ

P) equal to the difference between said emission power (P_e) and said reception power (P_r).

4. The mobile communication and localization device according to claim 1, wherein each data packet further comprises a time stamp for each position data, and wherein each position data comprises:

the estimated distance from a mobile network device, if directly reachable, wherein the time stamp associated to said position data indicates the time elapsed between the instant of reception of the data packet containing the power data used for calculating said estimated distance and the instant of transmission of said data packet;

a shortest path length, in the case of a first mobile network device belonging to a succession of mobile network devices and indirectly reachable through said succession, wherein the time stamp associated to said position data indicates the time elapsed between said instant of generation and said instant of transmission.

5. The mobile communication and localization device according to claim 1, further comprising localization means adapted to estimate the absolute position of the mobile communication and localization device itself, and said data packets comprise estimated absolute positions of corresponding mobile network devices.

6. The mobile communication and localization device according to claim 1, further comprising means for displaying the position of said mobile network devices.

7. A mobile communication system comprising a plurality of mobile communication and localization devices according to claim 1.

8. A mobile communication system comprising a plurality of mobile communication and localization devices according to claim 1, wherein said mobile communication and localization devices gain access to said communication channel in accordance with an arbitration algorithm.

9. The mobile communication system according to claim 8, wherein said arbitration algorithm assigns different priority levels to said mobile communication and localization devices depending on whether said mobile communication and localization devices are in alarm status or not.

10. The mobile communication and localization device according to claim 2, wherein said data structure is configured in a manner such that said information about a corresponding mobile network device contained in each entry comprises:

the estimated distance from said mobile network device, the time stamp associated thereto indicating the instant of reception of the data packet containing the power data used for calculating said estimated distance;

a shortest path length, in the case of a first mobile network device belonging to a succession of mobile network devices and indirectly reachable through said succession, wherein the time stamp associated to said information indicating an instant of generation of a data packet by said first mobile network device.

11. The mobile communication and localization device according to claim 4, wherein said means for determining said relative position of said mobile network devices comprise:

means for determining the instant of reception of each data packet;

means for calculating, for each mobile network device identified by a position data contained in said data packet, a time stamp equal to the difference between the instant of reception and the time stamp associated to said position data;

means for verifying if said data structure comprises an entry pertaining to said identified mobile network device;

means for generating a new entry, which are activated in the event that there is no entry for said identified mobile network device, and which associate the shortest path length increased by one unit and said time stamp with said identified mobile network device;

means for comparing the calculated time stamp with a stored time stamp, which are activated in the event that said entry for said identified mobile network device already exists and contains said stored time stamp, and for updating said entry if said calculated time stamp is subsequent to said stored time stamp.