DE10228890B4 - Method for controlling the transmission access to a bidirectional information channel - Google Patents

Abstract

Method for controlling the transmission access to a bidirectional information channel by a subscriber to a communication chain to be formed from a plurality of subscribers located at different locations, wherein the communication is via the bidirectional information channel by means of information blocks sent and received by the subscribers, the information blocks indicating the locations of the individual subscribers and a subscriber selects the time t _{s of} his access to the information channel in dependence on the spatial distance d of the subscriber, who has timely made a transmit access to the information channel, characterized in that the transmission time t _s by an internal processing time T _{i of} the Participant is temporally forwarded.

Description

The The invention relates to a method for controlling the transmission access to a bidirectional (transmit and receive) information channel by a participant in one of several, in different places participants to be formed communication chain, wherein the communication over the bidirectional information channel by means of the participants sent and received information blocks happens.

at modern motor vehicles can Driver assistance systems assist the driver by holding the handlebars a vehicle with information about the traffic around supply the vehicle around.

For this is a vehicle-vehicle communication necessary to the information and data (traffic and road condition information) from one vehicle to another.

To the Establishing such a communication will use a radio link Find. The information is in the form of data blocks between exchanged the stations.

Such communication between vehicles is out of the DE 44 34 789 in which vehicles are connected to a vehicle-vehicle communication by means of a radio link which serves to avoid rear-end collisions. In this case, data obtained by means of a global positioning system (GPS) is exchanged between vehicles located within a reception radius of the transmitters and receivers of the radio link.

adversely this is that no exchange of data with vehicles is possible, not in the reception or transmission range of a subscriber of the multi-page Communication, and that no directed dissemination of information possible is.

Out WO 00/42737 is a cordless fixed local area network (Local area network, LAN), in which a message considering of internal processing time by individual participants of the network is passed through them in a chain. The individual participants Send the received information immediately again. A Synchronization of the individual participants, when they are allowed to send, takes place strictly by the known internal processing time and by Registration at the network itself. A network control not yet known Participant can join the network in an extra, network-wide short radio break log.

adversely here is that the network of a central control unit administrative is controlled. A dynamic communication with ever-changing Location and network reception conditions are not possible.

^Nd 52 Vehicular Technology Conference, IEEE, 24th-28.9: from WO 00/23966 and from Te Min Sun, Wu Chi Feng, Ten Hwang Lai such as "GPS-Based Message Broadcast for Adaptive Inter-vehicle Communications" In . 2000, Vol. 6, pages 2685-2692 a method for spreading a message in a radio communication network with changing number of participants for forwarding the message is known, in which each participant has a transmitting and receiving device for messages and a positioning system for determining its position having. The forwarding of a message takes place after a predetermined waiting time t, which decreases monotonically with increasing distance between the receiver and transmitter.

task The invention is a method for controlling the transmission access to a bidirectional information channel by a subscriber one of several, located in different places participants To provide to be formed communication chain, in which a Dynamic decentralized adaptation of the shipments takes place to collisions in the transmission chain to avoid.

These The object is achieved by a method for controlling the transmission access to a bidirectional information channel according to claim 1.

The method according to the invention provides that the information blocks include location information of the individual participants and a subscriber selects the time t _{s of} its access to the information channel in dependence on the spatial distance d of the subscriber, in particular along the route, the time before him a transmit access to the information channel Has. In this case, the participant preferably reacts only to participants who are either in front of or behind him along the route.

This makes it possible to form a chain of several subscribers without administrative and restrictive transmission permission or assigned transmission times, wherein the individual subscribers do not have to know each other before sending. By the location data that are part of the information blocks, each participant to the previously sent to the information channel other participants its spatial distance to this be vote. As a temporal successor, he now sends his information block depending on the distance itself. A collision of transmission accesses of several participants receiving an information block is effectively avoided and at the same time automatically generates the transmission order locally.

By The invention is the creation of effective and uncomplicated Driver assistance systems, for example, the driver of a vehicle as a participant in the Support the communication chain by telling him about the Traffic in front of the vehicle at a distance of some Kilometers. there can be any vehicle ahead as a sensor and data source for his Serve successors. By collecting and compressing information the vehicles in front can be a meaningful picture of the Derive the traffic situation in front of a vehicle. Each involved Vehicle receives Data from preceding vehicles and sends information to his Successor. This is an information flow based on direct vehicle-vehicle communication without central or restrictive Network control possible.

An advantageous embodiment of the method provides that the transmission time t _s to the ratio of actual spatial distance d to previously transmitting participants to a preselected or actual maximum spatial propagation range D _{max of} a transmitted information block on the information channel multiplied by a preselected delay time T _v the actual reception time t _{e of} an information block of the previously transmitting subscriber. This clearly determines when an individual subscriber is allowed to initiate a send access in relation to his spatial distance from the previously transmitting subscriber.

The transmission time t _e is temporally advanced according to a preferred embodiment of the method by the internal processing time T _{i of} the subscriber. As a result, structurally-related differences and thus temporal transmission time differences of not necessarily the same structure and working participants are excluded from the outset.

A particularly advantageous and therefore preferred embodiment of the method provides that the transmission time after the relationship t s = t e - T i + (d / Dmax) · T v . where t _s = transmission time, t _e = reception time of the information block, T _i = internal processing time by the subscriber, T _v = delay time, D _max = maximum spatial propagation range of a transmitted information block on the information channel, d = spatial distance to the subscriber, who last sent on the information channel is. As a result, it is particularly clear when a time successor may start transmitting access to the information channel after receiving an information block.

A further advantageous method step provides that after a preselected period T _W without receiving an information block, a subscriber sends a current information block on the information channel. As a result, the start of a communication chain is made possible in a particularly effective manner, since a subscriber automatically offers himself as a potential first link in a communication chain.

Following is provided in a further advantageous method step that after a preselected waiting time period T _W, in particular> 2T _C without receiving an information block, a subscriber cyclically sends a current information block with a period T _C on the information channel. In this way, it is clearly regulated when a subscriber without receiving information blocks offers himself as a new potential first link in an information chain. The preferred choice of T _W > 2T _C ensures that no member of the communication chain is declared the first member in the event of a telegram failure and determines access to the information channel itself.

A preferred method step provides that the delay time T _v is chosen such that, in the case of a communication chain comprising several subscribers, the currently transmitting subscriber from the first transmitting subscriber whose period T _{C is} currently running has at least twice the maximum spatial spread range (2 · D _maX ) of a sent information _block on the information _channel is removed. This ensures that the first transmitting subscriber does not disturb the subscribers transmitting in time, or interferes with their broadcasts.

An advantageous embodiment of the method provides that the first member of a communication chain stops the cyclical transmission of an information block and behaves like a follower as soon as it receives a relevant information block of a new subscriber. A transmission access to the information channel is only permitted if the time T _{C has} elapsed since the last access. This ensures that when an existing communication chain with a first transmitting subscriber who has previously received no information blocks or attention to receive a relevant information block of a new subscriber, attaching the entire communication chain to the new subscriber is possible without any problems.

One advantageous process step provides that only from one to Dialing spatial Minimum distance between a first and a second participant the second participant in time after the first sending first Subscriber sends an information block. This is a time critical Procedure ensured and unnecessary information accumulation avoided.

To an advantageous method step is provided that the participants on a train - too Driving distance called - located and / or move and only information blocks from spatially in the direction of movement before each participant lying be attended to by other participants. This is a backward information chain allows, without that for example for a driver on a street unimportant information from behind him driving participants to him arrives.

To In another advantageous method step, information blocks of spatial in the direction of movement behind each participant looked at other participants, so that a forward-looking Info chain allows becomes.

One Another preferred method step provides that the participants Send your own location and movement information in the information block. hereby can compare with your own position and direction data be determined by the receiving party, whether the sending party in front or behind the vehicle and in the same direction is in motion. This allows a decision to be made Whether to respond to the receipt of an information block or not, whereby a movement direction-dependent communication is enabled.

According to one Next process step send the participants in the information block Location and movement information of spatially in the direction of movement in front of them other participants. This will be the information relayed to participants further down the chain, so they receive information from participants whose information blocks they use can not receive yourself.

Especially Advantageously, the information channel is selected as a radio channel. Of the Advantage lies in the safe and cheap transmission. Here are also optical or acoustic (for example ultrasound) transmission paths conceivable.

The Location and movement information will be according to another embodiment of the method by means of a global positioning system (e.g. GPS) won. This is a particularly simple and accurate evaluation and sending your own location information possible.

One particularly advantageous and therefore preferred method step provides that the received information blocks of the other participants through each participant will be evaluated and / or that the information of the received information blocks summarized and / or evaluated the information block to be sent enclosed become. This is an effective information compression and Thus utilization by clear summary of the previous ones information blocks possible, without the information blocks with each passing on the information of the previous participant - straight with long chains - always longer become.

A advantageous embodiment of the invention provides that the information blocks of a participant consecutively sending other participants be used to the maximum spatial propagation range set a sent information block on the information channel. Through this evaluation of the data and subsequent determination of the distances their subscribers in terms of time can subscribe to a communication chain adjust their own transmission range to optimize the flow of information to enable.

To a modification of the procedure, certain participants to Broadcast of information blocks selected or it is allowed in certain distance ranges of individual participants following Participants randomly send information blocks. You can do this certain markers are sent in the information blocks that Allow recipients to recognize if they send out information blocks may or Not. This will be unnecessary Broadcasts with a high number of participants in the propagation area a sending participant avoided.

According to one preferred embodiment of the method, the participants are land, Air or land vehicles on a directional road. the Following the participants are advantageously motor vehicles. Here But also water or air vehicles are possible and useful.

From Advantage in the information block more road condition information, especially weather conditions Posted.

Further advantages, special features and expedient developments of the invention will become apparent from the other dependent claims or their sub-combinations.

following the invention will be further explained with reference to the drawing.

there shows:

1 a schematic timing over the time t of the communication chain to three consecutive times.

The 1 shows the continuation of a communication chain between participants in the form of motor vehicles on a road at three successive times from top to bottom. The vehicles involved in the system are equipped with a single-channel radio communication device with an omnidirectional radiating and receiving antenna and a locating module (for example GPS). The locator module provides information about the current position and the direction of travel. All information blocks are sent in broadcast mode and are received by all subscribers within radio range.

The order of transmission access is determined by the numbering of the vehicles ( 1 to 15 ) is applied against the direction of travel to the left.

In the example, the transmission range D _max to the vehicle number 4 reaches after the first subscriber in the information chain (vehicle number 1).

After the shipment of vehicle 1 receive all vehicles 2 to 4 the information block composed of location and movement data (see top row in the figure). First of all, all receiving vehicles from the location and movement data of vehicle number 1 determine whether the information block is relevant to them - that is, whether vehicle number 1 is traveling in front of them on the same road. This is the case. Therefore, the vehicles determine 2 to 4 now their distance d to the vehicle 1 , With the distance d obtained, the waiting time until the transmission access is determined in the manner described above. Vehicle number 2 begins with the transmission access (see middle row in the figure), as it is the shortest distance to the vehicle 1 has before the other vehicles do a send access. This then from vehicle 2 sent out information package solves the calculations of subsequent vehicles that can receive the information packet (vehicle 3 to 6 ), new. This process is repeated for each relevant transmission of a vehicle in the communication chain.

The state after the expiration of the period T _C for the vehicle number 1 - without receiving blocks of information relevant to each other - is shown in the bottom row in the figure. The information chain has in the meantime propagated up to vehicle number 10, which is more than twice the transmission range (D _max ), so that the renewed transmission access of the vehicle number 1 further propagates against the direction of travel until the vehicle has transmitted access 15 does not bother.

The Invention allows This is a predictive driver assistance system. Because no directed Radio communication is not equipped vehicles, especially trucks, no obstacle in the communication system. With appropriate Radio range already reaches a relatively small degree of equipment to build highly effective communication chains.

There the vehicles with low transmission priority during the waiting period continue the received information blocks evaluate the vehicles in front, is a complex evaluation the received data possible.

Claims (19)

Method for controlling the transmission access to a bidirectional information channel by a subscriber to a communication chain to be formed from a plurality of subscribers located at different locations, wherein the communication is via the bidirectional information channel by means of information blocks sent and received by the subscribers, the information blocks indicating the locations of the individual subscribers and a subscriber selects the time t _{s of} his access to the information channel in dependence on the spatial distance d of the subscriber, who has timely made a transmit access to the information channel, characterized in that the transmission time t _s by an internal processing time T _{i of} the Participant is temporally forwarded. Method for controlling the transmission access to a bidirectional information channel according to claim 1, characterized in that the transmission time according to the relationship t s = t e - T i + (d / D Max ) * T v . where t _s = transmission time, t _e = reception time of the information block, T _i = internal processing time by the subscriber, T _v = delay time, D _max = maximum spatial spread range of a transmitted information block on the information channel, d = spatial distance to the subscriber who has last sent on the information channel is. Method for controlling the transmission access to a bidirectional information channel according to claim 2, characterized in that the delay time T _v is selected so that in a multi-subscriber communication chain of the currently transmitting participants from the first transmitting subscriber whose period T _C for the repeated transmission of an information block is in progress, at least by twice the maximum spatial propagation range (2 · D _max ) of a sent information block on the information channel is removed. Method for controlling the transmission access to a bidirectional information channel according to one of the preceding claims, characterized in that after a preselected period T _W without receiving an information block, a subscriber sends a current information block on the information channel. Method for controlling the transmission access to a bidirectional information channel according to one of the preceding claims, characterized in that after a preselected waiting time T _W without receiving an information block, a subscriber cyclically sends a current information block with a period T _C on the information channel. Method for controlling the transmission access to a bidirectional information channel according to claim 5, characterized in that the waiting time period T _{W is} greater than the period T _{C is selected} in particular as the double period T _C. Method for controlling the transmission access to a bidirectional information channel according to one of claims 5 or 6, characterized in that the period T _C is selected such that in a multi-subscriber communication chain of the currently transmitting participants from the first transmitting subscriber whose period T _c is currently running, at least by twice the maximum spatial propagation range (2 · D _max ) of a transmitted information block on the information channel is removed. Method for controlling the transmission access to a bidirectional information channel according to one of the preceding Claims, characterized in that only from a minimum spatial distance to be selected between a first and a second participant, the second participant in time after the previously sending first participant an information block sends. Method for controlling the transmission access to a bidirectional information channel according to one of the preceding Claims, characterized in that the participants on a train are located or move and only blocks of information spatially in the direction of movement in front of the respective participant lying other participants to be considered. Method for controlling the transmission access to a bidirectional information channel according to one of the preceding Claims, characterized in that in the information block next own Local additional Movement information to be sent. Method for controlling the transmission access to a bidirectional information channel according to one of the preceding Claims, characterized in that the participants in the information block Location and movement information of spatially in the direction of movement send to other participants in front of them. Method for controlling the transmission access to a bidirectional information channel according to one of the preceding Claims, characterized in that the information channel is a radio channel is. Method for controlling the transmission access to a bidirectional information channel according to one of the preceding Claims, characterized in that the location and / or movement information obtained using a global positioning system (GPS). Method for controlling the transmission access to a bidirectional information channel according to one of the preceding Claims, characterized in that the received information blocks of other participants are evaluated by each participant and / or that summarized the information of the received information blocks and / or evaluated to be sent to the information block to be sent. Method for controlling the transmission access to a bidirectional information channel according to one of the preceding Claims, characterized in that the information blocks of a participant in time subsequently sending other participants to be used the maximum spatial Propagation range of a sent information block on the Set information channel. Method for controlling the transmission access to a bidirectional information channel according to any one of the preceding claims, characterized in that certain subscribers are selected for the transmission of information blocks or in certain distance ranges of individual subscribers following participants may send information blocks by a random process. Method for controlling the transmission access to a bidirectional information channel according to one of the preceding Claims, characterized in that the participants air or land vehicles are on a directional road. Method for controlling the transmission access to a bidirectional information channel according to one of the preceding Claims, characterized in that the participants motor vehicles with this necessary electronic equipment. Method for controlling the transmission access to a bidirectional information channel according to one of the preceding Claims, characterized in that the information block further road status information, especially weather conditions.