Communication apparatus and method for performing inter-vehicular communication

Patent metadata

Field	Value
Publication number	US-9907086-B2
Application number	US-201615202419-A
Country	US
Kind code	B2
Filing date	Jul 5, 2016
Priority date	Nov 29, 2013
Publication date	Feb 27, 2018
Grant date	Feb 27, 2018

Abstract

A communication apparatus for inter-vehicular communication according to the present invention includes: a network state estimating unit configured to estimate network state information indicating a current network state based on driving information and channel state information of neighboring vehicles; a network access controller configured to control whether to transmit a message based on the network state information; a transmission scheduler configured to control a transmission time point of the message based on the network state information; and a transmission buffer unit configured to delay transmission of the message according to the control of the transmission time point of the transmission scheduler.

First claim

What is claimed is:

1. A communication apparatus installed in a host vehicle, the apparatus comprising:
a driving information generator configured to generate a first vehicle safety message of the host vehicle comprising an identification of the host vehicle, location information of the host vehicle at a first time, a speed of the host vehicle at the first time, a movement direction of the host vehicle at the first time, a first time stamp indicative of the first time, a first message counter of the first vehicle safety message;
a transceiver configured to receive vehicle safety messages from nearby vehicles, each vehicle safety message comprising identification of a nearby vehicle transmitting the particular vehicle safety message, location information of the nearby vehicle, a speed of the nearby vehicle, a movement direction of the nearby vehicle, a time stamp, and a message counter of the particular vehicle safety message, the transceiver further configured to broadcast the first vehicle safety message generated from the driving information generator; and
at least one controller configured:
to compute transmission probability (P TX ) using a tracking error (TE) such that the higher the TE is, the higher the P TX becomes,
to determine, based on the P TX , whether to transmit a vehicle safety message of the host vehicle,
to compute a first delay time for transmitting the first vehicle safety message of the host vehicle,
to cause the first vehicle safety message of the host vehicle to be stored in a buffer, and
subsequent to temporarily storing and computing the first delay time, to cause the transceiver to transmit the first vehicle safety message of the host vehicle according to the first delay time.

2. The apparatus of claim 1 , wherein the at least one controller is further configured:
to define timeframes in view of the received vehicle safety messages such that each timeframe comprises a plurality of timeslots, each timeslot for transmitting the host vehicle's vehicle safety message or for receiving a nearby vehicle's vehicle safety message; and
subsequent to determining for transmitting, to select a first one of the timeslots within a first timeframe available for transmitting the first vehicle safety message,
wherein computing the first delay time is performed subsequent to selecting the first slot, wherein the first delay time is to the first timeslot of the first timeframe.

3. The communication apparatus of claim 1 , wherein the at least one controller is further configured:
to generate a random number, and
to compare the random number against the P TX for determining whether to transmit a vehicle safety message of the host vehicle.

4. The communication apparatus of claim 1 , wherein the at least one controller is further configured to process the received vehicle safety messages for generating a packet error rate (PER) and a density, wherein the PER is generated for each nearby vehicle and represents an error rate of receiving vehicle safety messages from each nearby vehicle, wherein the density represents a count of vehicles within a range.

5. The communication apparatus of claim 4 , wherein the at least one controller is further configured to process the received vehicle safety messages for generating a channel busy ratio (CBR) in addition to the PER and the density, wherein the CBR represents a ratio of busy time within a timeframe.

6. The communication apparatus of claim 5 , wherein the first vehicle safety message further comprises the CBR generated using the received vehicle safety messages from nearby vehicles.

7. The communication apparatus of claim 5 , wherein the PER, the CBR and the density are generated using the received vehicle safety messages from nearby vehicles that are located within a range defined by a distance from the host vehicle.

8. The communication apparatus of claim 5 , wherein the at least one controller is further configured to adjust a wireless transmission power for transmitting the first vehicle safety message of the host vehicle in view of at least one of the PER, the CBR and the density.

9. The communication apparatus of claim 8 , wherein the wireless transmission power is adjusted such that the higher the CBR, the lower the wireless transmission power becomes.

10. The communication apparatus of claim 1 , wherein the at least one controller is further configured to delete a previously stored message from the buffer prior to storing the first vehicle safety message in the buffer.

11. A method of operating a vehicle, the method comprising:
providing the communication apparatus of claim 1 ;
wirelessly receiving, via the transceiver, vehicle safety messages from nearby vehicles, each vehicle safety message comprising identification of a nearby vehicle transmitting the particular vehicle safety message, location information of the nearby vehicle, a speed of the nearby vehicle, a movement direction of the nearby vehicle, and a message counter of the particular vehicle safety message;
computing transmission probability (P TX ) using a tracking error (TE) such that the higher the TE is, the higher the P TX becomes;
determining, based on the P TX , whether to transmit a vehicle safety message of the host vehicle;
generating a second vehicle safety message of the host vehicle comprising an identification of the host vehicle, location information of the host vehicle at a second time, a speed of the host vehicle at the second time, a movement direction of the host vehicle at the second time, a second time stamp indicative of the second time, and a second message counter of the second vehicle safety message;
computing a second delay time for transmitting the second vehicle safety message of the host vehicle;
temporarily storing the second vehicle safety message of the host vehicle in the buffer; and
subsequent to temporarily storing and computing the second delay time, transmitting, via the transceiver, the second vehicle safety message of the host vehicle according to the second delay time.

12. The method of claim 11 , wherein determining whether to transmit a vehicle safety message of the host vehicle comprises:
generating a random number; and
comparing the random number against the P TX for the determination.

13. The method of claim 12 , wherein transmission of the first vehicle safety message is determined when the random number is greater than P TX , wherein no transmission is determined when the random number is smaller than P TX .

14. The method of claim 11 , wherein the second vehicle safety message of the host vehicle is generated prior to determining whether to transmit.

15. The method of claim 11 , further comprising:
processing the received vehicle safety messages for generating a packet error rate (PER) and a density, wherein the PER is generated for each nearby vehicle and represents an error rate of receiving vehicle safety messages from each nearby vehicle, wherein the density represents a count of vehicles within a range.

16. The method of claim 15 , wherein the PER and the density are generated using the received vehicle safety messages from nearby vehicles that are located within a range defined by a distance from the host vehicle.

17. The method of claim 15 , wherein the P TX is computed using PER in addition to TE.

18. The method of claim 15 , further comprising adjusting a wireless transmission data rate for transmitting the second vehicle safety message of the host vehicle in view of at least one of the PER and the density.

19. The method of claim 15

Assignees

• Hyundai Mobis Co Ltd

Inventors

• Bai Song Nan
• Jung Jae Il
• Kim Tae Won
• Yi Won Jae

Classifications

• H04W72/542 Primary

  using measured or perceived quality · CPC title

• H04L43/16

  Threshold monitoring · CPC title

• H04W28/14

  using intermediate storage · CPC title

• H04W4/46

  for vehicle-to-vehicle communication [V2V] · CPC title

• H04W4/40

  for vehicles, e.g. vehicle-to-pedestrians [V2P] · CPC title