MULTICASTING SYSTEM AND METHOD FOR VEHICULAR COMMUNICATION NETWORK

• US 20120314643A1
• Filed: 06/12/2012
• Published: 12/13/2012
• Est. Priority Date: 06/13/2011
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: KIM, Jung-Sook, KWAK, Dong-Yong, KIM, Dong-Kyoo
• Granted Patent: US 8,797,938 B2
• Time in Patent Office: Days
• US Class Current: 370/312
• CPC Class Codes: H04L 12/1886 with traffic restrictions for efficiency improvement, e.g. involving subnets or subdomains
• CPC Class Codes: H04L 12/189 in combination with wireless systems selective distribution or broadcast in wireless communication networks H04W4/06
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/30 Resource management for broadcast services
• CPC Class Codes: H04W 76/40 for selective distribution or broadcast

Abstract

Disclosed herein are a multicasting system and method for a vehicular communication network. The multicasting system includes a plurality of roadside communication devices for communicating with a plurality of vehicular communication devices. Each of the roadside communication devices includes a communication unit for communicating with the plurality of vehicular communication devices and at least one neighboring roadside communication device, a beacon analysis unit for analyzing beacon frames when a slot allocation request is received from one of the vehicular communication devices, a determination unit for searching for a period in which a slot has not been allocated and determining whether a period for allocation of a slot to the vehicular communication device is present, and a slot allocation unit for allocating a slot period for multicasting of the vehicular communication device based on results of the determination of the determination unit.

Claims

1. A multicasting system for a vehicular communication network, comprising a plurality of roadside communication devices for communicating with a plurality of vehicular communication devices, wherein each of the roadside communication devices comprises:

a communication unit for communicating with the plurality of vehicular communication devices and at least one neighboring roadside communication device;

a beacon analysis unit for analyzing beacon frames from the corresponding roadside communication device and the at least one neighboring roadside communication device when a slot allocation request is received from one of the vehicular communication devices;

a determination unit for searching for a period in which a slot has not been allocated by the corresponding roadside communication device and the at least one neighboring roadside communication device and determining whether a period for allocation of a slot to the vehicular communication device is present; and

a slot allocation unit for allocating a slot period for multicasting of the vehicular communication device based on results of the determination of the determination unit.

2. The multicasting system of claim 1, wherein the determination unit searches for a period in which a slot has not been allocated in common by the corresponding roadside communication device and the at least one neighboring roadside communication device.

3. The multicasting system of claim 1, wherein the communication unit communicates using superframes that are used in a Time Division Multiple Access (TDMA) Media Access Control (MAC) communication system.

4. The multicasting system of claim 3, wherein each of the superframes comprises a beacon period in which the beacon frame of the roadside communication device is sent, a competitive advantage period in which media is accessed, a non-competitive multicast period in which the slot period is allocated to the vehicular communication device, and a non-competitive unicast period in which the vehicular communication device sends data packets via the allocated slot period.

5. The multicasting system of claim 1, wherein:

the slot allocation unit sends information about the allocation of the slot period to the vehicular communication device with the information included in a beacon frame; and

the information about the allocation of the slot period is stored in an MCP TimeSlotAllocationInfo field of the beacon frame.

6. The multicasting system of claim 5, wherein the MCP TimeSlotAllocationInfo field of the beacon frame comprises MCP TimeSlotInfo fields containing n pieces of information about slots allocated by the slot allocation unit, and a length field containing information about a number of the MCP TimeSlotInfo fields.

7. The multicasting system of claim 6, wherein each of the MCP TimeSlotInfo fields comprises at least one of a field containing information about allocation or non-allocation of a slot, an owner ID field containing information about an ID of a communication device to which the slot was allocated, a TimeSlot location field containing information about a location of the corresponding slot, and a Time Slot duration field containing information about a length of the corresponding slot.

8. The multicasting system of claim 1, wherein the slot allocation unit, when the vehicular communication device enters a data communication area of the corresponding roadside communication device after a slot period has been allocated by the at least one neighboring roadside communication device, allocates information about the entry of the corresponding vehicular communication device to a period which belongs to a slot period of the beacon frame of the corresponding roadside communication device and which corresponds to the slot period allocated by the at least one neighboring roadside communication device.

9. The multicasting system of claim 1, wherein the communication unit is connected, via communication, to neighboring roadside communication devices which are spaced apart by one hop.

10. A multicasting method for a vehicular communication network, comprising a plurality of roadside communication devices for communicating with a plurality of vehicular communication devices, the method comprising, by each of the roadside communication devices:

receiving a beacon frame from at least one neighboring roadside communication device when a slot allocation request is received from each of the vehicular communication devices;

analyzing beacon frames received from the corresponding roadside communication device and the at least one neighboring roadside communication device;

searching for a period in which a slot has not been allocated by the corresponding roadside communication device and the at least one neighboring roadside communication device; and

allocating a slot period for multicasting of the vehicular communication device based on results of the searching of the determination unit.

11. The multicasting method of claim 10, wherein the searching comprises searching for a period in which a slot has not been allocated in common by the corresponding roadside communication device and the at least one neighboring roadside communication device.

12. The multicasting method of claim 10, wherein:

the allocating comprises sending information about the allocation of the slot period to the vehicular communication device with the information included in a beacon frame; and

the information about the allocation of the slot period is stored in an MCP TimeSlotAllocationInfo field of the beacon frame.

13. The multicasting method of claim 12, wherein the MCP TimeSlotAllocationInfo field of the beacon frame comprises MCP TimeSlotInfo fields containing n pieces of information about allocated slots, and a length field containing information about a number of the MCP TimeSlotInfo fields.

14. The multicasting method of claim 13, wherein each of the MCP TimeSlotInfo fields comprises at least one of a field containing information about allocation or non-allocation of a slot, an owner ID field containing information about an ID of a communication device to which the slot was allocated, a TimeSlot location field containing information about a location of the corresponding slot, and a Time Slot duration field containing information about a length of the corresponding slot.

15. The multicasting method of claim 10, wherein the allocating comprises, when the vehicular communication device enters a data communication area of the corresponding roadside communication device after a slot period has been allocated by the at least one neighboring roadside communication device, allocating information about the entry of the corresponding vehicular communication device to a period which belongs to a slot period of the beacon frame of the corresponding roadside communication device and which corresponds to the slot period allocated by the at least one neighboring roadside communication device.

16. The multicasting method of claim 10, wherein the receiving comprises receiving a beacon frame from at least one neighboring roadside communication device which is spaced apart by one hop.