Abstract:
An exemplary vehicular apparatus includes a radio frequency receiver adapted for receipt of signals transmitted from intelligent street sins. A computer receives recovered digital data from the receiver, where the digital data represents information contained in the signals received by the receiver. The computer parses the digital data into separate fields and identifies a first field containing a first value that represents a predetermined type of vehicle for which the information contained in the other fields is relevant. The computer compares the first value with a stored value in memory to determine if the information contained in the other fields is relevant to the vehicle and recovers the information contained in the other fields if it is determined that the other fields are relevant to the vehicle.

Description:
BACKGROUND 
   This invention relates to the wireless transmission of data associated with vehicular transportation and more specifically relates to interpreting such data by a vehicle. 
   Advances in technology along with lower costs are giving rise to new opportunities for new or improved communications. For example, wireless cellular communications are supported in most metropolitan cities around the world. In addition to voice communications, many of such cellular systems also support text messaging. Internet access utilizing a laptop computer or a personal digital assistant makes data communications possible from a variety of wireless (WI-FI) hot spots such as at hotels, airports, coffee shops, etc. The proliferation of such technologies results in efficiencies in manufacturing and lower costs of production. 
   Global positioning satellite (GPS) receivers are available as stand-alone portable units as well as vehicular mounted units. As long as the GPS receiver can receive acceptable signals, location information can be accurately conveyed to the user such as a driver of a vehicle. Available GPS systems can show the current location of a vehicle on a displayed map of the area and can provide route instructions for getting to a specified destination. 
   Despite such advances in communications, only limited data communication systems have been developed to provide information concerning conditions or events relevant to a driver and/or vehicle over the course of a journey of the vehicle. In one known system transmitters having a limited range of only a few hundred feet were deployed along a bus route. The transmitters transmitted data information by which each route marker was uniquely identified. The buses were provided with a data receiver to receive these transmissions. A separate conventional two-way radio was coupled to the data receiver in the buses which allowed the received data to be transmitted to a bus control center so that the position of the buses could be accurately monitored over the course of the bus route. This facilitated the management of a fleet of buses in a city. In another system a wireless transponder mounted in a car communicates with a communication device located at highway toll plazas facilitates the payment of tolls without requiring the car to come to a stop at the plaza. Although such data communication systems have proved useful, there exists a need to provide and utilize additional information related to the journey of a vehicle relating to conditions or events along the journey. 
   SUMMARY 
   It is an object of the present invention to satisfy this need. 
   An exemplary vehicular apparatus includes a radio frequency receiver adapted for receipt of signals transmitted from intelligent street signs. A computer receives recovered digital data from the receiver, where the digital data represents information contained in the signals received by the receiver. The computer parses the digital data into separate fields and identifies a first field containing a first value that represents a predetermined type of vehicle for which the information contained in the other fields is relevant. The computer compares the first value with a stored value in memory to determine if the information contained in the other fields is relevant to the vehicle and recovers the information contained in the other fields if it is determined that the other fields are relevant to the vehicle. 
   The present invention also encompasses an exemplary system that includes intelligent street signs and vehicles that can benefit therefrom, as well as an exemplary method for implementing such vehicular assistance. 

   
     DESCRIPTION OF THE DRAWINGS 
     Features of exemplary implementations of the invention will become apparent from the description, the claims, and the accompanying drawings in which: 
       FIG. 1  is a block diagram of an intelligent street sign environment and a vehicle suited for implementing an embodiment of the present invention. 
       FIG. 2  is a block diagram of an exemplary apparatus disposed in a vehicle 
       FIG. 3  is diagram showing an illustrative communication format for the reception of data by a vehicle from an intelligent street sign in accordance with the present invention. 
   

   DETAILED DESCRIPTION 
   One aspect of the present invention resides in the recognition of the difficulties associated with determining whether received data from an intelligent street sign is relevant to a particular vehicle, and if so, how it is relevant. This aspect is complicated by the desire to have vehicles only need a receiver to receive street sign data as contrasted with the vehicle also being capable of transmitting information to intelligent street signs. 
     FIG. 1  shows exemplary intelligent stop street sign  10  and speed limit street sign  12  each capable of transmitting a wireless signal that can be received within areas  14  and  16 , respectively. The street signs are disposed along a road  18  which an exemplary vehicle  20  is traveling in the direction as indicated by arrow  22 . 
   The intelligent stop street sign  10  includes a transmitter  24  connected to an antenna  26  for radiating a signal having an effective area  14 . A power source, such as a solar panel,  28  coupled with a storage battery provides a source of power for transmitter  24  enabling it to transmit continuously. The transmitter  24  preferably includes nonvolatile memory that stores data that is repetitively transmitted. The type of information transmitted and the communications protocol utilized are discussed below. The intelligent speed limit street sign  12  has substantially similar elements to street sign  10  but of course transmits different data. 
   Vehicle  20  which may for example comprise a car or truck utilizes an antenna  30  coupled to a communication apparatus  32  configured for reception and processing of the signals transmitted by intelligent street signs. As shown in  FIG. 1 , vehicle  20  is just entering the area  14  in which the signal transmitted by the intelligent stop sign  10  can be received. As vehicle  20  travels in the direction as indicated by arrow  22 , it will pass through area  14 , enter a region  34  in which no intelligent street sign signal is present, and enter area  16  in which the signal from intelligent speed limit street sign  12  is present. Thus, the vehicle  20  will receive the signal from sign  10  while in area  14  and will receive the signal from sign  12  while in area  16 . In the illustrative example, areas  14  and  16  do not overlap so that a region  34  exists in which no street sign signal will be received by vehicle  20 . However, street signs can be disposed such that overlapping coverage areas exist. 
     FIG. 2  illustrates an exemplary communication apparatus  32  in which antenna  30  couples received signals to radio frequency (RF) receiver  40 . A computer  42  includes a central processing unit (microprocessor)  44  that is supported by read-only memory (ROM)  46 , random access memory (RAM)  48  and nonvolatile data storage element  50  that may comprise a hard drive. As will be understood by those skilled in the art, ROM  46  and/or data storage  50  will contain program control instructions that will be typically transferred at least in part to RAM  48  for operation and control of the computing functions implemented by computer  42 . An input/output (I/O) module  52  is coupled to CPU  44  and supports communications with external elements, i.e. the receipt of incoming data to computer  42  and the transmission of outgoing data from computer  42 . 
   The receiver  40  receives the RF signals transmitted from the intelligent street signs and demodulates the received RF signals into binary data that is transmitted to the I/O module  52 . This binary data is processed by CPU  44  in accordance with stored program instructions to parse the binary data into predetermined fields or binary bytes. The information (values) contained in the binary bytes is compared against values stored in computer  42  in order to determine what information has been conveyed. A further discussion of the communication protocol and the significance of data in predetermined fields are provided below in association with  FIG. 3 . 
   A user input device  54  such as a keyboard, mouse or touch screen provides a means for inputting user information and commands to computer  42 . A user display  56  such as an LCD screen provides a means for displaying information to the user. A vehicle display  58  such as a vehicle dashboard display module provides a further means for displaying information to the user. An exemplary navigation system  60  such as a GPS system is capable of providing location related information to and receiving location related information from computer  42 . A vehicle input/output module  62  provides an interface by which the computer  42  can receive information generated by the vehicle&#39;s electronic system, e.g. the speed of the vehicle, and can transmit control signals to the vehicle&#39;s electronic system, e.g. turn-on headlights, blow the horn, etc. It will be apparent that these are merely examples of the various inputs and controls that can be utilized depending upon the desired application. Examples of the operation of computer  42  in conjunction with the peripheral devices are provided below. 
     FIG. 3  shows an illustrative communication protocol in which a series of binary bytes form a packet  70  that is decoded by receiver  40  and transmitted to computer  42  for interpretation. The packet  70  is divided into a plurality of fields where each field may contain a value that can be correlated into corresponding information by the computer  42  by comparing the values in the fields to predetermined value stored in the computer associated with corresponding information. For example, field  72  may contain a value that defines the number of fields or bytes contained in packet  70 . Field  74  may contain a value that identifies the type or types of vehicles for which the information is relevant. For example values of 1, 2, 3 or 4 in field  74  may correspond to all vehicles, cars, trucks under a specified weight and trucks over a specified weight, respectively. It will be understood that various additional or alternate values could be utilized for field  74  in order to distinguish information intended for only certain vehicles or types of vehicles. The use of such a field  74  enables computer  42  to easily and quickly determine if a received packet contains information in additional fields that is relevant to the vehicle containing the computer. For example, if field  74  identifies the packet as being only relevant to trucks over a specified weight, then the computer need not decode the remainder of the fields where the computer is in a car. The remaining fields including fields  76  and  78  will contain values that correspond to related information associated with the intelligent street sign. For example, one the fields can contain a value representing for which direction of travel of a vehicle the sign information is relevant. That is, a “sharp left curve ahead” sign posted before the curve would only be relevant for vehicles approaching the curve, not vehicles traveling in the other direction that will have already gone through the subject curve. This direction value could be compass based, e.g. a value of “180” would indicate it is relevant for vehicles traveling substantially South (180), but not for vehicles traveling North (0 or 360). This of course requires the computer of the vehicle to know its direction of travel which can be determined by navigation information. 
   In addition to information related to the control or regulation of vehicles, the intelligent street signs may store and transmit location information of the street sign that can be contained within packet  70 . This provides vehicles with at least periodic geographic location information. Time and/or date information may also be contained within these fields where such information is relevant to traffic control. For example, speed zones adjacent schools are often only in force during times when school is in session. Some traffic control signs are only relevant during specific time periods, e.g. “no left turn from 4–6 p.m.” Thus, such predetermined time and/or date information can be compared with the current time and/or date as determined by computer  42  to determine whether the traffic control information and/or restrictions currently apply. 
   In order for the computer  42  to make determinations and comparisons, the user will need to input certain information into the computer that can be stored for later use. For example, it is preferable that the computer generate a start up set of questions or menus that will guide the user through the inputting of the required information. For example, the user can be requested to input the type of vehicle in which the computer is disposed or to select a type of vehicle from a displayed list. Depending upon the specific vehicle, additional information or selections may be required, e.g. choosing a weight class for a truck, the number of axles of the vehicle, height of the vehicle, etc. If the computer  42  is also to be utilized for navigation over the course of a trip, the user may be requested to enter a current location, intermediate points along a route and a final destination so that location information received along the route from the intelligent street signs can be utilized to determine the current location of the vehicle relative to the intended route. Depending upon whether the computer has access to the other time/date information sources, the user may also be requested to enter the current time and date. The information sought from the user may be conveyed by the user display  56 . User input  54  can be utilized to input the requested information that can be stored in nonvolatile a storage element  50  for subsequent use. Alternatively, such user input can be entered and locked to prevent unauthorized changes from being made. 
   Various uses exist for the information received from the intelligent street signs. One straightforward use is to simply display the information to the user via the user display  56  or the vehicle display  58 . For example, as the vehicle enters area  14  indicating that the vehicle is approaching the intelligent stop street sign, the word “STOP” or the symbol for a stop sign could be displayed. 
   Assuming that the speed of the vehicle is available to computer  42  from module  62 , an alert may be provided to the driver if the speed of the vehicle is not being reduced at a sufficient rate after entering area  14 . For example, the alert may consist of displaying a large flashing stop sign symbol and/or providing an audible alert, e.g. sounding the horn. While the vehicle is within area  16 , the applicable speed limit can be displayed and an alert can be provided to the driver if the current speed of the vehicle exceeds the speed limit or exceeds the speed limit by a predetermined percentage. 
   The data received from intelligent street signs can be utilized to interact with or control other car systems if desired. For example, upon receiving a packet from a street sign containing information indicating the entrance to a tunnel, the computer could automatically generate a command that would be transmitted to module  62  to cause the vehicle&#39;s headlights, if not already on, to be turned on. Upon receiving a packet from a street sign indicating that the vehicle is entering a quiet zone, the computer could automatically generate a command that would cause the sound level of the horn, if activated, to be at a reduced level. The vehicle&#39;s cruise control setting could be automatically changed upon entering a new reduced speed limit zone as determined by the receipt of a packet from a speed limit street sign. Based on the information received from intelligent street signs, a variety of actions or events associated with the operation of the vehicle could be automatically taken. Of course, safety of the driver and passengers remain paramount and hence some actions that could be automatically taken may be inappropriate if safety is adversely impacted. 
   Even if a navigation system module  60  is present, location information derived from intelligent street signs can be utilized to augment the information generated by module  60 . The vehicle may be in a location in which the GPS receiver of module  60  is unable to receive sufficient GPS signals to determine a current location. For example, while the vehicle is in a tunnel, location information received from an intelligent road sign can be utilized to confirm the location of the vehicle. 
   Although exemplary implementations of the invention have been depicted and described in detail herein, it will be apparent to those skilled in the art that various modifications, additions, substitutions, and the like can be made without departing from the spirit of the invention. For example, various types of RF communications could be utilized to carry the intelligent street sign information such as IEEE 802.11, 806.16 or 3G wireless communications. Receivers and transmitters for implementing such wireless communications are available. Actions such as automatically braking upon approaching a stop sign at too great a speed could be implemented assuming that it is determined that this would be in the best interest of safety for the occupants of the vehicle as well as others. 
   The scope of the invention is defined in the following claims.