FR2783380A1 - Object identification and discrimination method, e.g. for public transport vehicles, assigning objects a time interval for signal transmission with coding by physical or time attributes - Google Patents

Abstract

Each object to be identified, e.g. a bus (1a, 1b), is allocated at least a first specific time interval during which it transmits a first signal (3a, 3b) to a central receiving station (2). The objects are coded by allocation of a physical and/or time variable which is also specific to them, and each carries a GPS receiver to enable determination of their position and speed. An Independent claim is included for the application of the method of the invention to the location of mobile objects, especially vehicles.

Description

Method and system for identifying and discriminating objects.

  The present invention relates to a method, system and devices

  allowing the identification and the discrimination of objects.

  Methods, systems and devices are known which make it possible to identify and discriminate objects from a distance, in particular public transport vehicles in a fleet of vehicles. To solve this problem, each object is assigned an identification code. The different codings used are based on the assignment, for each object, of continuous physical properties over time. It is generally a shape, a color, a code or a frequency: these characteristics are specific to an object, and there are as many as there are objects (for example n frequencies for n objects). This results in a bulk

disadvantageous wireless.

  The present invention relates to a new method and a new system making it possible to solve the problem posed without presenting the

  disadvantages of those that exist.

  According to the invention, the method of serial transmission of information from distinct objects belonging to a set of objects, and of identification of said objects, comprises the step of allocating to each object of said set of objects at least a first time interval during which said object emits, in particular generates and transmits by radio, wire or in any other way, a first signal towards at least one receiver. Said first time interval is specific to one or more objects. The method according to the invention also comprises the step of coding said objects by attributing to one or more determined objects a physical and / or temporal characteristic specific to said determined objects. By physical characteristics is meant in particular an identifier in the form of a series of digits. By temporal characteristics is meant in particular an identifier in the form of an allocation of time intervals. Thus each receiver receiving said transmitted signal can recognize the object from which said signal comes. The object which emits in the time interval tn, tn + 1

is object n.

  Preferably, the method according to the invention is such that each object receives a second signal from a time frame. Thus it is possible to synchronize the objects with respect to said time frame and with each other. This avoids time drifts which could distort the identification of the object to which a time interval has been allocated

specific.

  Preferably also, the method according to the invention is such that it comprises the step of allocating to each object several first time intervals during which said object transmits said first signal in the direction of said receiver or receivers. Said first time intervals are specific to one or more objects. Thanks to this characteristic feature of the method according to the invention, each receiver can, on different dates, identify and distinguish an object from another object. Advantageously, said first time intervals allocated to each object are distributed cyclically over time. This characteristic feature facilitates the management of

  system implementing the method according to the invention.

  According to an essential preferential characteristic of the process according to

  the invention, the transmission frequency of each first signal is the same.

  Thanks to this characteristic, the spectral bulk is reduced.

  Preferably, the method according to the invention further comprises the step of allocating to each object of said set of objects at least a second

  time interval, distinct from said first specific time interval.

  During said second time interval said object receives a third signal from at least one transmitter. Said second time interval is specific to one or more objects. Thus, it is possible to transfer data from the transmitter to said object, in particular it is possible to reconfigure the physical and / or temporal characteristics

specific of said objects.

  Preferably, the method according to the invention further comprises the step of allocating to each object of said set of objects several second time intervals, distinct from said first specific time intervals, during which said object receives said third signal from of said transmitter (s). Said second time intervals are specific to one or more objects. Thanks to this characteristic feature, each issuer can, on different dates, contact each object. Preferably, the transmission frequency of each third signal is the same

  and is in particular equal to the transmission frequency of each first signal.

  Thanks to this characteristic feature, the spectral bulk is reduced.

  Advantageously, the method and the system implementing the invention are such that each receiver and / or each transmitter is also an object. Thanks to this characteristic feature, the exchange of information takes place within a network of which all the elements are interconnected with the

  same functional possibilities.

  The invention also relates to the devices and the system which make it possible to implement the method according to the invention, in particular the system and

  the devices which will be described below with reference to the figures.

  The invention also relates to the application of the method and the system to

  the identification of mobile objects, in particular transport vehicles.

  Advantageously in this case, each object comprises a GPS receiver.

  Thus, it is possible to determine the position and / or the speed of each

  object (of each vehicle) then transmit it to each receiver.

  Other characteristics and advantages of the invention will become apparent on

  reading of the description of variant embodiments of the invention, given

  by way of an indicative and nonlimiting example, and of: FIG. 1 showing a perspective view of an alternative embodiment of the system and of the method according to the invention, in the case where the objects are transport vehicles, - Figure 2 showing the graph of allocations of time intervals, - Figure 3 showing in the form of block diagrams the electronic architecture of an object according to the invention, - Figure 4 showing in the form of block diagrams l 'architecture

  electronics of a receiver according to the invention.

  We will now describe Figure 1 which shows a perspective view of an alternative embodiment of the system and method according to the invention, in the case where the objects are transport vehicles la, lb. Each transport vehicle la, lb is allocated first time intervals iael, iae2 and ibel, ibe2, ibe3 (see graph in FIG. 2) during which vehicles la and lb respectively generate and transmit a first signal 3a over the air. , 3b in the direction of the processing center 2. The transmission frequency of each first signal 3a, 3b is the same. The spectral bulk is thus reduced. In the alternative embodiment shown in Figures 1 and 2, said first time intervals are specific to a single vehicle. In other alternative embodiments, said first time intervals could be specific to several vehicles. The vehicle la is coded by allocation of the first time intervals iae 1, iae2. When the processing center 2 receives a signal during the time intervals iael and iae2, it identifies that this signal has been emitted by the vehicle la. Similarly, when the processing center receives a signal during the time intervals ibel, ibe2, ibe3, it identifies that this signal has been emitted by the vehicle lb. Each vehicle 1a, 1b receives a second signal from a time reference system. In the variant embodiment shown in FIG. 1, this time frame is provided by a constellation of GPS (Global Positioning System) satellites 4a, 4b, 4c transmitting signals 5aa, 5ba, 5ca in the direction of the vehicle la and signals 5ab , 5bb, 5cb towards the vehicle lb. They also send signals towards the processing center 2. Thus, it is possible to synchronize the vehicles 1a and 1b and the processing center 2 with respect to said time frame. This avoids time drift that could distort the identification of vehicles

  which have been allocated a specific time interval.

  Allocating to each vehicle la, lb several first time intervals iael, iae2 and ibel, ibe2, ibe3, during which said vehicles emit said first signal in the direction of processing center 2, makes it possible to identify and distinguish a vehicle from another vehicle, on different dates. Advantageously, said first time intervals allocated to each object are distributed cyclically over time. This trait

  characteristic facilitates their management.

  Each transport vehicle 1a and 1b is allocated a second time interval iar and ibr (see graph 2). The second time intervals are distinct from said first specific time intervals iael, iae2 and ibel, ibe2, ibe3. During said second time interval, the vehicle receives a third signal from at least one transmitter. In the variant embodiment shown in FIG. 1, the transmitter is the processing center 2. Thus, it is possible to transfer data from the processing center 2 to the vehicles 1a and 1b, in particular it is possible to reallocate the intervals of specific times. The transmission frequency of each third signal is the same and is in particular equal to the transmission frequency of each first signal. Congestion

spectral is thus reduced.

  In other variant embodiments than those shown with reference to FIGS. 1 and 2, each vehicle in said fleet of vehicles is allocated several second time intervals, distinct from said first specific time intervals. Thus, the processing center 2 can, at different

dates, contact each vehicle.

  We will now describe FIG. 3 which represents, in the form of block diagrams, the electronic architecture of the transmission and reception circuits of vehicles 1a and 1b, to or from the center of

  processing 2 and satellites 4a, 4b, 4c.

  A power supply 30, in particular a battery, supplies the electrical energy necessary for the operation of the GPS receiver 31, of the processing and calculation unit 32, of the electronic reception circuit 33, of the electronic transmission circuit 34. The unit 32 processing manages the operation of the electronic reception circuit 33 and the electronic transmission circuit 34 and applies the policy of allocation of predetermined time intervals. The processing unit 32 processes two types of information from the GPS receiver: location information (position, speed, etc.) and time information (the

  time repository) which allow the allocation of time intervals.

  The electronic reception circuit 33 and the electronic transmission circuit 34 are connected to the data transmission antenna 35 to or from the processing center 2. The antenna 36, connected to the GPS receiver 31, receives the GPS data . Thus, it is possible to determine the position and / or the speed of each vehicle la, lb then of the

  forward to processing center 2.

  We will now describe FIG. 4 which represents, in the form of block diagrams, the electronic architecture of the transmission and reception circuits of the processing center 2, to or from the vehicles 1a, 1b. A power supply 40, in particular a battery, supplies the electrical energy necessary for the operation of the GPS receiver 41, the GPS data processing unit 42, the other data processing unit 43, the

  electronic transmission circuit 44, electronic reception circuit 45.

  The antenna 47, connected to the GPS receiver 41, receives the GPS data.

  The GPS processing unit 42 processes the GPS time frame and ensures the time decoding of the vehicles 1a and 1b. The processing unit 43 manages the operation of the electronic reception circuit 45 and the electronic transmission circuit 44. The electronic reception circuit 45 and the electronic transmission circuit 44 are connected to the data transmission antenna 46 to or from vehicles la and lb. A display system 48 makes it possible to view the messages exchanged

  with said vehicles, including their identity and location.

Claims (11)

Claims   1. Method - of serial transmission of information from separate objects belonging to a set of objects, and of identification of said objects, said method being characterized in that it comprises the step - of allocating to each object of said set of objects at least a first time interval during which said object emits a first signal towards at least one receiver, said first time interval being specific to one or more objects, - to code said objects by attribution to one or more determined objects of a specific physical and / or temporal characteristic to said determined objects, (so that each receiver can receive said transmitted signal and   recognize the object from which said signal originates).   2. Method according to claim 1 such that: - each object receives a second signal coming from a time frame, (so that it is possible to synchronize the objects with respect to said   time frame and relative to each other).   3. Method according to claim 2 as it comprises the step - of allocating to each object several first time intervals during which said object transmits said first signal towards the said receiver (s), said first time intervals being specific to one or more objects, (so that each receiver can, on different dates, identify and   distinguish an object from another object).   4. Method according to claim 3 such that - the first time intervals allocated to each object are   distributed cyclically over time.   5. Method according to any one of claims 1 to 4 such as:   - the emission frequency of each first signal is the same,   (so that the spectral bulk is reduced).   6. Method according to any one of claims 1 to 5 as it   further comprises the step: - of allocating to each object of said set of objects at least a second time interval, distinct from said first specific time interval during which said object receives a third signal from at least one transmitter , said second time interval being specific to one or more objects, (so that it is possible to reconfigure the physical characteristics   and / or specific temporal of said objects).   7. Method according to any one of claims 1 to 6 as it   further comprises the step: of allocating to each object of said set of objects several second time intervals, distinct from said first specific time intervals, during which said object receives said third signal from the said transmitter (s), said second time intervals being specific to one or more objects, (so that each transmitter can, on different dates, contact each object).   8. Method according to any one of claims 6 to 7 such as:   the transmission frequency of each third signal is the same and is in particular equal to the transmission frequency of each first signal,   (so that the spectral bulk is reduced).   9. Method according to any one of claims 1 to 8 such as   each receiver and / or each transmitter is also an object.   10. Application of the method according to any one of   Claims 1 to 9 to the identification of moving objects, in particular   vehicles. 11. Application according to claim 10 such that each object comprises a GPS receiver, (so that it is possible to determine the position and / or the speed of   each object and then transmit it to each receiver).