Methods for Data Communication to a Platoon of Connected Vehicles

• US 20170289864A1
• Filed: 03/16/2017
• Published: 10/05/2017
• Est. Priority Date: 04/01/2016
• Status: Active Grant

• Current Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Inventors: Narasimha, Murali, Sartori, Philippe, Desai, Vipul, Xiao, Weimin, Al-Shalash, Mazin Ali, Soong, Anthony C.K.
• Granted Patent: US 10,542,464 B2
• Time in Patent Office: Days
• CPC Class Codes: H04W 36/0009 for a plurality of users or terminals, e.g. group communication or moving wireless networks user group management H04W4/08; processing of subscriber group data H04W8/186
• CPC Class Codes: H04W 36/0027 for a plurality of data sessions of end-to-end connections, e.g. multi-call or multi-bearer end-to-end data connections
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 36/32 by location or mobility data, e.g. speed data
• CPC Class Codes: H04W 36/36 by user or terminal equipment

Abstract

It is possible to reduce latency and/or overhead when performing a platoon handover by using the leading vehicle in the platoon to communicate handover requests and/or initial resource requests (e.g., random access transmissions) on behalf of trailing vehicles in the platoon. In one example, a leading vehicle in a platoon communicates a handover request to a source AP to request handover of the entire platoon from the source AP to a target AP. In such an example, the source AP then communicates handover commands to each vehicle in the platoon without receiving separate handover requests from the trailing vehicles, thereby reducing overhead in the access network. The handover commands notify the trailing vehicles of the handover, and may be sequentially communicated to the trailing vehicles based on their order in the platoon.

Claims

1. A method for sequential handovers, the method comprising:

receiving, by a source access point, a handover request from a leading vehicle in a platoon of vehicles, the leading vehicle being followed by one or more trailing vehicles, wherein the handover request requests a handover from a source access point to a target access point; and

transmitting by the source access point, handover commands to the one or more trailing vehicles in response to the handover request received from the leading vehicle.

2. The method of claim 1, wherein the handover commands transmitted by the source access point schedules the one or more trailing vehicles to transmit uplink random access transmissions to the target access point according to a sequence of time periods, wherein trailing vehicles positioned nearer to the leading vehicle are assigned earlier time periods than trailing vehicles positioned further from the leading vehicle.

3. The method of claim 1, wherein the handover commands are communicated directly from the source access point to the one or more trailing vehicles.

4. The method of claim 1, wherein the handover commands are relayed through the leading vehicle such that the handover commands are first communicated from the source access point to the leading vehicle, and then from the leading vehicle to the one or more trailing vehicles via direct vehicle-to-vehicle communication.

5. A method for low-overhead handover, the method comprising:

receiving, by a trailing vehicle in a platoon of vehicles, a handover command from a source access point in response to a handover request from a leading vehicle in the platoon of vehicles, the trailing vehicle following the leading vehicle in the platoon of vehicles wherein the handover command indicates a handover from the source access point to a target access point ;

receiving, by the trailing vehicle, a handover complete command from the target access point, the handover complete command scheduling resources of the target access point to the trailing vehicle; and

transmitting or receiving, by the trailing vehicle, data to or from the target access point over the scheduled resources.

6. The method of claim 5, wherein the handover complete command is received from the target access point prior to the trailing vehicle transmitting any uplink signaling to the target access point.

7. The method of claim 5, wherein the handover command received from the source access point instructs the trailing vehicle to transmit an uplink random access transmission in a corresponding time period in a sequence of time periods, wherein a delay between the time period assigned to the trailing vehicle and an earlier time period assigned to the leading vehicle corresponds to a distance between the trailing vehicle and the leading vehicle.

8. A method for sequential handovers, the method comprising:

receiving, by a target access point, a random access transmission from a leading vehicle in a platoon of vehicles, the leading vehicle being followed by one or more trailing vehicles, wherein the random access transmission requests scheduled resources of the target access point; and

transmitting, by the target access point, handover complete commands to the one or more trailing vehicles based on the random access transmission received from the leading vehicle without receiving separate resource requests from the trailing vehicles, the handover complete commands scheduling resources of the target access point to the one or more trailing vehicles.

9. The method of claim 8, wherein the handover complete commands are sequentially transmitted from the target access point to the one or more trailing vehicles based on an order of the one or more trailing vehicles in the platoon of vehicles.

10. The method of claim 8, wherein the handover complete commands are communicated from the target access point to each the one or more trailing vehicles prior to the target access point receiving a separate uplink transmission from the respective trailing vehicle.

11. A method for sequential handovers, the method comprising:

receiving, by a trailing vehicle in a platoon of vehicles, a handover command from a source access point, the trailing vehicle following a leading vehicle in the platoon of vehicles, wherein the handover command indicates a handover from the source access point to a target access point;

receiving, by the trailing vehicle, a handover complete command from the target access point prior to transmitting any uplink signaling to the target access point, the handover complete command scheduling resources of the target access point to the trailing vehicle; and

transmitting or receiving, by the trailing vehicle, data to or from the target access point over the scheduled resources.

12. A method for low overhead control signaling, the method comprising:

receiving, by an access point, channel information from a leading vehicle in a platoon of vehicles;

assigning a transmission parameter to the leading vehicle at a first time instance based on the channel information received from the leading vehicle; and

assigning the transmission parameter to a trailing vehicle at a second time instance based at least one of a speed in which the platoon of vehicles is traveling and a spacing between the leading vehicle and the trailing vehicle.

13. The method of claim 12, wherein the transmission parameter is an uplink or downlink modulation and coding scheme (MCS) level.

14. The method of claim 12, wherein the transmission parameter is a set of beamforming weights used for uplink or downlink transmission.

15. The method of claim 12, wherein the transmission parameter is an uplink timing advance corresponding to a propagation delay of a signal communicated to the access point.

16. A method for low overhead control signaling, the method comprising:

receiving, by a trailing vehicle in a platoon of vehicles, a transmission parameter from an access point prior to communicating any channel information, the transmission parameter having been assigned based on channel information received from a leading vehicle in the platoon of vehicles and at least one of a speed in which the platoon of vehicles is traveling and a spacing between the leading vehicle and the trailing vehicle; and

transmitting or receiving a signal to or from the access point according to the transmission parameter.

17. The method of claim 16, wherein the transmission parameter is an uplink or downlink modulation and coding scheme (MCS) level assigned by the access point.

18. The method of claim 17, further comprising:

estimating a channel information value based on a downlink reference signal received from the access point;

comparing a channel information value associated with the assigned MCS level with the estimated channel information value; and

transmitting an uplink feedback message to the access point when a difference between the channel information value associated with the assigned MCS level and the estimated channel information value exceeds a threshold, the uplink feedback message including the estimated channel information value.

19. The method of claim 16, wherein the transmission parameter is a set of beamforming weights used for uplink or downlink transmission.

20. The method of claim 16, wherein the transmission parameter includes at least one uplink timing advance corresponding to a length of time an uplink signal takes to reach the access point after being transmitted by the trailing vehicle.

21. The method of claim 16, wherein the transmission parameter includes a sequence of timing advances, and wherein transmitting or receiving the signal according to the transmission parameter comprises:

transmitting a first uplink signal to the access point according to a first timing advance in the sequence of timing advance; and

after expiration of a delay period, transmitting a second uplink signal to the access point according to a second timing advance in the sequence of timing advance.

22. A method for low overhead control signaling, the method comprising:

assigning, by an access point, a first transmission parameter value to a leading vehicle in a platoon of vehicles at a first time instance; and

assigning, by the access point, a second transmission parameter value to a trailing vehicle at a second time instance based on at least one of the distance between the leading vehicle and the trailing vehicle and the speed of the platoon, the second time instance occurring after first time instance.

23. The method of claim 22, wherein the second transmission parameter value is a beam direction.

24. The method of claim 22, wherein the second transmission parameter value is a transmit power level.

25. The method of claim 22, wherein the second transmission parameter value is a timing advance setting.

26. An apparatus comprising:

a processor; and

a non-transitory computer readable storage medium storing programming for execution by the processor, the programming including instructions to;

receive a handover request from a leading vehicle in a platoon of vehicles, the leading vehicle being followed by one or more trailing vehicles, wherein the handover request requests a handover from a source access point to a target access point; and

transmit by the source access point, handover commands to the one or more trailing vehicles in response to the handover request received from the leading vehicle.