A Survey Of Inter-Vehicle

ugliestmysticAI and Robotics

Nov 14, 2013 (4 years and 1 month ago)

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A Survey Of Inter
-
Vehicle
Communication Protocols And
Their Applications

A summary

Table of Content


Classification of applications


Communication requirements


Design decisions


Design tradeoffs


Discussion


Conclusion


Classification of Applications

1.
General Information Services

2.
Vehicle Safety Information Services

3.
Individual Motion Control

4.
Group Motion Control

Classification of Applications

General information services

Scope:


Does not involve the automatic control of vehicles


Does not involve vehicle safety


General information services generally require:


Low communication overhead


High information delivery ratio



Examples:


Mobile internet


P2P data queries

Scope:


Does involve vehicle safety


Delayed information may result in compromised safety or
renders application useless


Tolerance to delay generally increases with source
-
receiver distance


Examples:


Accident warning


Obstacle warning


Dissemination of road conditions

Classification of Applications

Vehicle safety information services

Classification of Applications

Individual motion control

Scope:


Keep vehicles out of each other’s way using individual
motion planning and regulation methods


No group motion is involved


Interaction with neighbors typically lasts for seconds or
minutes


Examples:


Adaptive cruise control


Vehicle collision avoidance

Classification of Applications

Group motion Control

Scope:


Generally involves organizing vehicles in groups

3 Types:

1.
Group planning with individual regulation


E.g. coordinated adaptive cruise control (CACC)

2.
Leader
-
based motion regulation


The leader coordinates the joining and leaving of vehicles

3.
Virtual leader motion regulation


Directives arrive using a distributed consensus process



Many
-
to
-
many communication may be used

Communication requirements

Latency:


Types 2 & 3 require hard real
-
time latencies


Type 4 requires soft real
-
time latencies

Reliability:


Types 2 & 3 require a high
-
probable delivery of data


Type 4 requires the ability to determine whether the data
was received

Scaling:


Types 1 & 2 require a high scaling


Types 3 & 4 require a medium scaling

1.
General information services

2.
Vehicle Safety Information Services

3.
Individual Motion Control

4.
Group Motion Control


Communication requirements

Scope:


The scope of types 1 & 2 may be larger than 3 & 4 as they
do not physically interact.

GroupStructure:


Types 1, 2 & 3 require non
-
persistent relationships


Type 4 requires persistent relationships

1.
General information services

2.
Vehicle Safety Information Services

3.
Individual Motion Control

4.
Group Motion Control


Design decisions

Considerations:


Medium Access Schemes


TDMA, IEEE802.11


Access Mapping


Can be done based on location, tokens, etc.


Communication Organization


Common approaches: flooding, opportunistic flooding, clustering


Definition of Receiver Group


Cluster membership, geographic location, reception group


Network resource allocation


Lower consumption of resources (e.g. using TTL or priorities)


Group Membership Services


Implicit or explicit membership

Design tradeoffs

Design Decision

Impact on Communication Service

Primary

Secondary or indirect

Access Scheme and Mapping

Scaling w/ Vehicle Density,
Reliability, Latency

-

Communication Organization

Scaling w/ Vehicle Number, Scope

Reliability, Latency

Definition of Receiver Group

Group Structure, Scope

Scaling, Reliability, Latency

Network Resource Allocation

Scaling w/ Vehicle Density & Number,
Latency, Reliability

Scope

Group Membership Services

Group Structure, Reliability

-

Selected protocols

Type 1:
MDDV Protocol


Opportunistic flooding


Geocast


Reliability of 90%
-
100% in simulations

Type 2:
VCWC Protocol



Application
-
specific congestion control


Scale well

Type 3:
ADS
-
B Protocol


Periodic broadcast of motion reports


No acknowledgements

Type 4:
RNP Protocol



Operates on top of Mobile Reliable Broadcast Protocol (M
-
RBP)


Verification of message reception

1.
General information services

2.
Vehicle Safety Information Services

3.
Individual Motion Control

4.
Group Motion Control


Discussion


Many protocols are very specific in solving problems for
certain applications


Layered protocol architecture may prevail in the future


It is unclear if the advantages of integrated protocols
outweigh their disadvantages



Transportation applications are likely to evolve into a
complete system that addresses many applications using
multiple protocols (e.g. AHS)

Conclusion


4 types of applications


For each application the requirements were identified


Focus on major design decisions


Tradeoffs in the design greatly impact the performance


Set of protocols was analyzed using these tradeoffs for
each application