Architecture, method, and program for generating realistic vehicular mobility patterns

1. An adaptive vehicular movement simulator comprising:

a computer comprising:

a user interface for receiving at least one input parameter related to simulation topology and at least two input parameters related to simulation vehicles, one of the at least two input parameters being a linear vehicular density;

a simulation initialization module for creating the simulation topology having a simulation area using the at least one input parameter related to the simulation topology;

a vehicle movement simulation module for placing a plurality of simulation vehicles with the simulation area at an initial placement based upon the at least two input parameters related to simulation vehicles and the created simulation topology and simulating movement of the plurality of simulation vehicles starting with the initial placement using a plurality of movement models, each of the plurality of simulation vehicles has mobility characteristics determined by plurality of movement models, when the simulated movement moves a vehicle outside the simulation area, the vehicle re-emerges at a location within the simulation area; and

a converter for converting the simulated movement into an application specific format for a mobile wireless network simulating program selected from a plurality of predetermined application specific formats, the application specific formats are stored in a storage device.

2. The adaptive vehicular movement simulator of claim 1 , wherein the at least one input parameter is selected from a group comprising of a city block dimension, a number of blocks, an active block dimension, a lane width, a number of directions of traffic flow, a number of lanes per direction of traffic flow, a simulation time, traffic light locations and duration of traffic light.

3. The adaptive vehicular movement simulator of claim 1 , wherein another of the at least two input parameters related to simulation vehicles is selected from a group comprising a minimum vehicle speed and a maximum vehicle speed.

4. The adaptive vehicular movement simulator of claim 3 , wherein each of the plurality of vehicles is assigned a random target speed between the minimum vehicle speed and the maximum vehicle speed.

5. The adaptive vehicular movement simulator of claim 1 , wherein the initial placement of the plurality of simulation vehicles is random.

6. The adaptive vehicular movement simulator of claim 1 , wherein the initial placement of the plurality of simulation vehicles includes determining a number of vehicles in the plurality of simulation vehicles using the linear vehicular density and a calculated length for each street.

7. The adaptive vehicular movement simulator of claim 1 , wherein when the simulated movement moves a vehicle outside the simulation area, the vehicle re-emerges at a location within the simulation area with new mobility characteristics.

8. The adaptive vehicular movement simulator of claim 7 , wherein when the simulated movement moves a vehicle outside the simulation area, the vehicle re-emerges at the beginning of the same lane in which the vehicle was located.

9. The adaptive vehicular movement simulator of claim 7 , wherein when the simulated movement moves a vehicle outside the simulation area, the vehicle re-emerges at a random location.

10. The adaptive vehicular movement simulator of claim 1 , wherein the plurality of movement models is selected from a group comprising a car-following model, a lane changing model and a traffic light model.

11. A method for simulating vehicular movement comprising the computer implemented steps of:

receiving at least one input parameter related to simulation topology and at least two input parameters related to simulation vehicles, one of the at least two input parameters being a linear vehicular density;

generating the simulation topology having a simulation area using the at least one input parameter related to the simulation topology;

placing a plurality of simulation vehicles within the simulation area at an initial placement using the at least two input parameters related to simulation vehicle and said generated simulation topology;

determining movement of the plurality of simulation vehicles starting with the initial placement using a plurality of movement models, each of the plurality of simulation vehicles has mobility characteristics generated using the plurality of movement models, when the movement moves a vehicle outside the simulation area, the vehicle re-emerges at a location within the simulation area; and

generating an application specific format for a wireless network simulating program selected from a plurality of mobile wireless network simulating programs for said determined movement, a format for the application specific format for the plurality of simulating programs is stored in a storage device.

12. The method for simulating vehicular movement of claim 11 , wherein the plurality of movement models is selected from a group comprising a car-following model, a lane changing model and a traffic light model.

13. The method for simulating vehicular movement of claim 12 , wherein the lane changing model comprises:

determining if a vehicle in a lane is blocked by another vehicle directly in front of the vehicle in the same lane;

determining if there is a safe gap in an adjacent lane; and

changing lanes to the adjacent lane based upon both determinations.

14. The method for simulating vehicular movement of claim 13 , wherein determining if a vehicle in a lane is blocked by another vehicle directly in front of the vehicle in the same lane further comprises;

determining a current speed the another vehicle directly in front;

determining a desired speed for the vehicle; and

comparing the desired speed to the current speed of the another vehicle directly in front,

wherein if the desired speed is less than the current speed of the another vehicle, the determining if a vehicle in a lane is blocked by another vehicle directly in front of the vehicle in the same lane further comprises:

calculating a distance between the vehicle and the another vehicle directly in front; and

comparing the calculated distance to a preset distance threshold.

15. The method for simulating vehicular movement of claim 13 , wherein the determining if there is a safe gap in a target lane further comprises:

retrieving the data structure for a current lane and the lanes adjacent to the current lane;

determining a position for a second vehicle immediately in front of the vehicle, in one of the adjacent lanes, and a third vehicle immediately behind the vehicle, in the same adjacent lane;

calculating a first distance between the vehicle and the second vehicle and a second distance between the vehicle and the third vehicle;

comparing the first distance and the second distance with a safe gap threshold; and

switching to one of the adjacent lanes based upon said comparisons.

16. The method for simulating vehicular movement of claim 12 , wherein said traffic light model comprises:

determining if a vehicle is at a position of a light;

determining if the light is red;

calculating a relative position of the vehicle and the red light;

comparing said calculated relative position with a predetermined distance;

determining a current speed for the vehicle;

comparing the current speed with a speed threshold; and

stopping for the red light based upon said comparisons.

17. A method for simulating vehicular movement using a computer comprising the computer implemented steps of:

receiving at least one input parameter related to simulation topology and at least two input parameters related to simulation vehicles, one of the at least two input parameters being a linear vehicular density;

generating the simulation topology having a simulation area using the at least one input parameter related to the simulation topology;

placing a plurality of simulation vehicles within the simulation area at an initial placement using the at least two input parameters related to simulation vehicle and said generated simulation topology; and

determining movement of the plurality of simulation vehicles starting with the initial placement using a plurality of movement models, each of the plurality of simulation vehicles has mobility characteristics generated using the plurality of movement models, when the movement moves a vehicle outside the simulation area, the vehicle re-emerges at a location within the simulation area;

wherein the at least one input parameter is selected from a group comprising of a city block dimension, a number of blocks, an active block dimension, a lane width, a number of directions of traffic flow, a number of lanes per direction of traffic flow, a simulation time, traffic light locations and duration of traffic light; and

wherein said generating said simulation topology comprises:

for each street,

calculating a street length based upon the city block dimension, the number of blocks, the active block dimension and lane width;

generating a street index number for said street;

generating a lane index number for each of the lanes in said street;

determining lane end points for each of the lanes in said street based upon the lane index number, street index number, street length and the input lane width; and

initializing at least one street and at least one lane data structure for maintaining vehicle order for each of the plurality of simulation vehicles within a street and lane.

18. The method for simulating vehicular movement of claim 17 , wherein said generating the simulation topology further comprises:

generating intersection points between horizontal and vertical streets;

placing traffic lights at the generated intersection points based upon the input traffic light locations; and

assigning a traffic light duration for each traffic light based upon the input duration of traffic light.

19. The method for simulating vehicular movement of claim 17 , wherein said placing a plurality of simulation vehicles within the simulation area at an initial placement comprises:

for each street,

calculating a number of vehicles for the street based upon the input linear vehicular density and calculated street length;

determining a number of lanes of travel for the street based upon said input number of directions of travel and the input number of lanes per direction of traffic flow;

assigning randomly a vehicle to a lane based upon said input number of lanes;

placing, within the randomly assigned lane, the vehicle at a random location within the lane between the calculated end points; and

sorting the at least one street and at least one lane data structures based upon a placed order of each vehicle, the leading vehicle in the street and each lane is first.

20. The method for simulating vehicular movement of claim 19 , wherein if the number of directions of traffic flow for the street is two, said placing a plurality of simulation vehicles within the simulation area at an initial placement further comprises:

dividing the calculated number of vehicles for the street in half; and

assigning randomly half the calculated number of vehicles for each direction of traffic flow.

21. The method for simulating vehicular movement of claim 19 , wherein another of the at least two input parameters related to simulation vehicles is selected from a group comprising a minimum vehicle speed and a maximum vehicle speed.

22. The method for simulating vehicular movement of claim 21 , wherein said placing a plurality of simulation vehicles within said simulation area at an initial placement further comprises:

determining, randomly, an initial speed for each vehicle, the initial random speed is set between the input minimum vehicle speed and the maximum vehicle speed.

23. A computer readable storage device tangibly embodying a program containing instructions for causing a computer to execute a method for simulating vehicular movement, said method comprising:

receiving at least one input parameter related to simulation topology and at least two input parameters related to simulation vehicles, one of the at least two input parameters being a linear vehicular density;

generating the simulation topology having a simulation area using the at least one input parameter related to the simulation topology;

placing a plurality of simulation vehicles within the simulation area at an initial placement using the at least two input parameters related to simulation vehicle and said generated simulation topology; and

determining movement of the plurality of simulation vehicles starting with the initial placement using a plurality of movement models, each of the plurality of simulation vehicles has mobility characteristics generated using the plurality of movement models, when the movement moves a vehicle outside the simulation area, the vehicle re-emerges at a location within the simulation area;

wherein the at least one input parameter is selected from a group comprising of a city block dimension, a number of blocks, an active block dimension, a lane width, a number of directions of traffic flow, a number of lanes per direction of traffic flow, a simulation time, traffic light locations and duration of traffic light; and

wherein said generating said simulation topology comprising:

for each street,

calculating a street length based upon the city block dimension, the number of blocks, the active block dimension and lane width;

generating a street index number for said street;

generating a lane index number for each of the lanes in said street;

determining lane end points for each of the lanes in said street based upon the lane index number, street index number, street length and the input lane width; and

initializing at least one street and at least one lane data structure for maintaining vehicle order for each of the plurality of simulation vehicles within a street and lane.