Abstract:
Systems and methods are provided for enforcing a vehicle code. The systems and methods employ wireless communication signals transmitted and received by mobile units, including mobile telephones, palm devices and base stations.

Description:
CROSS REFERENCE TO RELATED APPLICATION  
     This application claims priority from U.S. application Ser. No. 10/705,674 filed Nov. 10, 2003, issued as U.S. Pat. No. 7,123,926 on Oct. 17, 2006, which was a continuation of U.S. application Ser. No. 09/659,074 filed Sep. 11, 2000, issued as U.S. Pat. No. 6,647,270 on Nov. 11, 2003, which in turn claims priority from U.S. Provisional Application No. 60/153,424 filed Sep. 10, 1999, all of which are incorporated by reference as if fully set forth herein. 
     BACKGROUND 
     The present invention generally relates to communication systems. More particularly, the invention relates to a mobile communication system which allows mobile vehicles to communicate with neighboring vehicles and roadside communication networks. 
     Various communication systems have been used by automobile drivers to communicate with other vehicles while the vehicle is in motion. While many advances have been made in vehicle to vehicle communication, numerous disadvantages still remain in using conventional communication systems. 
     Conventional mobile communication systems include cellular telephones and CB or two-way radio. When using a cell phone as a means of mobile communication, there is no practical way of discovering whether a neighboring vehicle operator possesses a cell phone. Additionally, there is no process for determining the phone number of the targeted cell phone. Accordingly, the cell phone as a communication medium is severely limited. 
     CB radio is a widely broadcast public medium where mobile users may talk to other mobile or stationary users in their vicinity. However, since there is no ability to prevent others from listening, there is no privacy between mobile communicators. 
     Automobile accidents are one of the greatest causes of serious injury and fatalities in society. Accordingly, the development of improved control and warning systems to minimize personal and financial losses resulting from automobile accidents is of utmost importance. The limitations of present forms of communication are even more severe when considering the extent to which a communication link can improve both the driving experience and the safety statistics of modern vehicles. 
     SUMMARY 
     According to one aspect of the present application, a method is provided for enforcing a vehicle code. The method comprises receiving a wireless communication signal by a first mobile unit having a unique identifier. The wireless communication signal is transmitted by a second mobile unit associated with a vehicle. The method further comprises downconverting data in the received wireless communication signal from radio frequency to baseband; and determining, based on the downconverted data, a vehicle identifier associated with the vehicle, and a GPS position associated with the vehicle. The method still further comprising determining by a system administrator a status of the vehicle using the vehicle identifier to monitor the vehicle for code enforcement. Determining the status includes parsing the received wireless communication signal to determine the status of the vehicle. The method also comprises generating baseband message data indicating the status by constructing at least one data packet from a plurality of data fields. The data fields include the unique identifier of the first mobile unit and the vehicle identifier. In addition, the method includes up converting the baseband message data to radio frequency for transmission to the second mobile unit, thereby transmitting the upconverted baseband message data indicating the status of the vehicle. 
     According to another aspect of the present application, a system is disclosed for enforcing a vehicle code. The system comprises means for receiving a wireless communication signal by a first mobile unit having a unique identifier. The wireless communication signal is transmitted by a second mobile unit associated with a vehicle. The system further comprises means for downconverting data in the received wireless communication signal from radio frequency to baseband; and means for determining based on the downconverted data a vehicle identifier associated with the vehicle and a GPS position associated with the vehicle. The system still further comprises means for determining by a system administrator a status of the vehicle using the vehicle identifier to monitor the vehicle code enforcement. Determining the status includes parsing the received wireless communication signal to determine the status of the vehicle. The system also comprises means for generating baseband message data indicating the status by constructing at least one data packet from a plurality of data field, including the unique identifier of the first mobile unit and the vehicle identifier associated with the vehicle. In addition, the system comprises means for upconverting the baseband message data to radio frequency for transmission to the second mobile unit, thereby transmitting the upconverted baseband message data indicating the status of the vehicle. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING(S) 
         FIG. 1  shows an example vehicle communication system. 
         FIG. 2  is a block diagram showing a mobile unit in accordance with the example embodiment. 
         FIG. 3A  is a diagram illustrating the contents of a communication packet transmitted by the mobile unit shown in  FIG. 2 . 
         FIG. 3B  illustrates the header of the communication packet. 
         FIG. 3C  illustrates the information fields of the header&#39;s transmission administration. 
         FIG. 3D  illustrates the information fields of the header&#39;s sender portion. 
         FIG. 3E  illustrates the information fields of the header&#39;s receiver portion. 
         FIG. 3F  illustrates the sub fields contained in the identification number field. 
         FIG. 4A  illustrates the memory of the example mobile unit shown in  FIG. 2 . 
         FIG. 4B  is a diagram of a vehicle communication log. 
         FIG. 4C  is a diagram of a vehicle user log. 
         FIG. 4D  is a diagram of a vehicle contact log. 
         FIG. 5  is a flow diagram of the procedure utilized by the microprocessor upon receipt of a communication packet. 
         FIG. 6  is a flow diagram of the procedure for processing communication packets. 
     
    
    
     DETAILED DESCRIPTION  
     The present invention provides a communication link among vehicles which eliminates these pitfalls. The system comprises a broadband RF transceiver with antenna, a position determining means, such as a GPS receiver, and audio-visual interface, and electromechanical interface and a microprocessor with associated memory. These components are incorporated into a mobile unit located within each vehicle. 
     The GPS receiver receives signals from GPS satellites and calculates the position of the vehicle. The mocroprocessor carries out overall control of the system. The memory includes identification information that is unique to each vehicle. In response to input from the GPS receiver, information received by the transceiver and instructions input by the vehicle operator via the audio-visual interface, the microprocessor determines the necessary subsequent actions. 
     The transmission from a vehicle may include information describing the status of the vehicle for use of the receiving vehicle. For example, the transmission may provide information regarding the speed, direction and position of the transmitting vehicle. This information is received and processed by the receiving vehicle to provide a visual or audible display of the position, direction and speed of the transmitting vehicle. 
     According to one aspect of the present invention, there is provided a communication system for transmitting information between a mobile unit within a vehicle traveling on a road and a fixed communication network installed on a roadside. The fixed communication network includes a base station having a transceiver for communicating with the vehicle by transmitting and receiving a plurality of communication packets. This communication can include payment instructions, security instructions and/or access codes which can be transmitted with or without intervention by the vehicle operator. 
     An example embodiment will be described with reference to the drawing figures where identical numerals represent similar elements throughout. 
     A vehicle communication system embodying the present invention is shown in  FIG. 1 . The vehicle communication system  10  generally comprises one or more base stations  14 , each of which is in wireless communication with a plurality of remote units  16 . Although the remote units  16  may be fixed or mobile, they will be referred to hereinafter for simplicity as mobile units  16 . Each mobile unit  16  can communicate with another mobile unit  16 , the closest base station  14 , or the base station  14  which provides the strongest communication signal. The base stations  14  communicate with a base station controller  20 , which coordinates communications among base stations  14  and mobile units  16 . The communication system  10  may be connected to a public switched telephone network (PSTN)  22 , wherein the base station controller  20  also coordinates communications between the base stations  14  and the PSTN  22 . In the example embodiment, each base station  14  communicates with the base station controller  20  over a wireless link, although a land line may also be provided. A land line is particularly applicable when a base station  14  is in close proximity to the base station controller  20 . The fixed remote units  16  may also communicate with a base station  14  over a land line. 
     The base station controller  20  performs several functions. Primarily, the base station controller  20  provides all of the operations, administrative, and maintenance (OA&amp;M) signaling associated with establishing and maintaining all of the wireless communications between the mobile units  16 , the base stations  14  and the base station controller  20 . The base station controller  20  can provide the routing of all communications between mobile units  16 , and between the mobile units  16  and the PSTN  22 . The base station controller  20  also provides an interface between the mobile units  16  and the PSTN  22 . This interface includes multiplexing and demultiplexing of the communication signals that enter and leave the system  10  via the base station controller  20 . Although the vehicle communication system  10  is shown employing antennas to transmit radio frequency (“RF”) signals, one skilled in the art should recognize that communications may be accomplished via microwave or satellite uplinks. Additionally, the functions of the base station controller  20  may be combined with a base station  14  to form a “master base station.” 
     An example embodiment of the mobile unit  16  is shown in  FIG. 2 . Each mobile unit includes an RF transceiver  32  with an antenna  33  capable of transmitting and receiving a plurality of RF signals, a global positioning system (“GPS”) receiver  35 , a microprocessor  40  with associated memory  41 , an interface to the vehicle&#39;s electromechanical systems  44  and an audio-visual interface  46 . 
     The RF transceiver  32  transmits and receives RF signals at a plurality of RF frequencies to one or more vehicles which include a mobile unit  16 . Received signals are downloaded to baseband and forwarded to the microprocessor  40  for further processing. Transmitted signals are forwarded from the microprocessor  40  to the RF transceiver  32  for upconversion and transmission over one of the plurality of RF frequencies. The vehicle communication system  10  also provides for the option of transmitting a communication over currently licensed radio station channels, for example 105.9 FM. This can permit a mobile unit operator to broadcast to non-mobile unit operators. It also can provide a “scanning channel”, such that non-mobile unit operators can listen to broadcast communications. 
     The GPS receiver  35  is configured to receive signals from GPS satellites and compute the position of the mobile unit  16 . There are many commercially available GPS receivers  35  that can perform such a function. GPS readings which are provided to the microprocessor  40  permit the microprocessor  40  to accurately calculate the speed, direction, and acceleration or deceleration rate of the vehicle. 
     The microprocessor  40  provides central control of the mobile unit  16 . As will be explained in greater detail hereinafter, the microprocessor  40  also performs packet handling, including packet assembling for outgoing communication packets  50  and packet disassembling for incoming communication packets  50  received from the RF transceiver  32 . Communication packets  50  received by the microprocessor  40  are stored in memory  41 . The memory  41  is also used to store identification information that is unique to each vehicle and/or vehicle operator. For example, license and registration for each vehicle can be read if positioned with a bar code or magnetic strip in a specific location of the vehicle. Optionally, the system may have a card reader where the operator must place their card prior to the vehicle starting. This card can be a license with a magnetic strip or a smartcard that may identify the driver and the vehicle. This unique information regarding the vehicle may also include the position of the vehicle, speed of the vehicle and rate of acceleration or deceleration as calculated by data obtained from the GPS receiver  35 . 
     The audio-visual interface (AVI)  46  may comprise a microphone, speakers, and graphic display along with alphanumeric and directional keypads. However, those of skill in the art should realize that the AVI  46  may encompass other input devices which are known, such as a voice activated input unit, an infrared (“IR”) remote control, a full keyboard or any other type of electronic or manual data input means. Additionally, the output portion of the AVI  46  may comprise any type of output means such as a stereo system or a heads-up display. 
     The electro mechanical interface  44  provides an electrical coupling to the electro-mechanical systems of the vehicle over which the mobile unit  16  has control. These systems may include the radio, lights, horn, windows, locks, steering, breaking, and any other electromechanical systems of the vehicle. 
     Communications between mobile units  16  using the vehicle communication system  10  are accomplished through a stream of transmitted communication packets  50 . As shown in  FIG. 3A , each communication packet  50  comprises a header  51  and a payload  53 . The header  51  comprises a plurality of predefined information fields which provide information regarding the particular communication, the sender which originated the communication, and the receiver to which the communication is destined. It should be recognized that a voice or data communication may be segmented or “packetized” and transmitted using a plurality of packets  50 . The present invention is not restricted to transmitting a communication having a predefined length. Accordingly, the payload  53  may comprise only a portion of the communication that is sent between mobile units  16 , and a single communication may be sent using a plurality of packets  50 . Communications may comprise data transmissions, such as uploads from the mobile unit  16 , downloads to the mobile unit  16 , or voice communications. 
     Referring to  FIG. 3B , the header  51  comprises a plurality of information fields which can be generally categorized by three different functional groups: 1) transmission administrative information  55 ; 2) sender information  56 ; and 3) receiver information  57 . These fields will be explained in greater detail hereinafter. 
     Referring to  FIG. 3C , the information fields associated with the transmission administration  55  are shown. These fields provide information that defines the particular communication being transmitted. Although the number of fields may vary, and the type of fields described may change depending on the particular communication and the requirements of the system  10 , in one embodiment of the present application the fields associated with transmission administration  55  comprise the following fields: security  61 ; priority  62 ; in system/out of system  63 ; broadcast/point-to-point  64 ; communication identifier (data/voice)  65 ; communication type (information/control)  66 ; and communication length (standalone or continuous)  67 . 
     Since the vehicle communication system  10  in accordance with the present invention permits control of a vehicle and overall control of the communication system  10  by law enforcement authorities via a “security instruction”, the system  10  has a plurality of security levels to ensure that unauthorized individuals will not use the system  10  for subversive purposes. Optionally, driver may override law enforcement. The system  10  may ask for permission for law enforcement to control vehicle. The security field  61  is defined as follows: 
     0—Access to all functions of the vehicle communication system  10 , including the physical control of the vehicle and all of the information stored within the memory  41 . 
     1—Access only to the physical control of the vehicle. 
     2—Access only to the information stored within the memory  41 . 
     3—Access for transmitting and receiving communications. 
     4—Access only to receiving communications. 
     The security field  61  may also include a security code, which permits authentication of the entity sending the security instruction. As aforementioned, it should be understood by those skilled in the art that additional fields may be added or defined as desired to increase the functionality of the system  10  or the security layers. Additionally, it should be recognized that although the system  10  is capable of a broad range of functionality, there are legal implications to implementing all of the functionality. For example, a court order would most likely be necessary before permitting law enforcement officials access to information in, or control of, the mobile unit  16 . 
     The priority field  62  is an indicator of the urgency of the transmitted communication. The priority field  62  can be a numeric priority from one to ten; with urgent communications having the highest priority of one (e.g., communications from law enforcement officials) and non-urgent communications having the lowest priority of ten (e.g., advertisements). 
     The in system/out of system field  63  indicates whether the communication is destined for, or originated from, another mobile unit  16  or an entity located outside of the vehicle communication system  10 . Communications with entities outside the vehicle communication system  10  can be routed between the mobile unit  16  and the outside entity over the PSTN  22 . 
     The broadcast/point-to-point field  64  identifies whether the message is intended for broadcast to all mobile units  16  or whether it is intended to be routed to a particular mobile unit  16 . As will be explained in detail hereinafter, the receiver field  57  will specify the particular address, or multiple addresses, of the mobile units  16  to which the communication will be transmitted. 
     The communication identifier field  65  identifies whether the communication is a voice or data transmission since each transmission may be encoded and processed differently by the receiving microprocessor  40 . 
     The communication type field  66  identifies whether the communication comprises information for output to the user via the AVI  46 , or whether the information is a control instruction that will permit electromechanical control of the vehicle. 
     The communication length field  67  indicates whether the entire communication is included within the current packet  50 , or whether the packet  50  is part of a multi-packet communication. 
     Referring to  FIG. 3D , the fields associated with the sender portion  56  of the header  51  include identification number  71 , position  72 , speed  73 , acceleration or deceleration  74 , direction  75 , origination  76 , and destination  77 , and may include additional optional fields  78  as specified by the vehicle operator. 
     The identification number  71  provides a unique identification for the sending mobile unit  16 . The identification number may be the vehicle license number with two additional letters representing the state where the license plate was issued, such as PA for Pennsylvania. Depending upon system administration, the identification number  71  may further relate to one or more individual operators of the vehicle. As shown in  FIG. 3F , the identification number field  71  may comprise a plurality of subfields including vehicle code  81 , number of authorized vehicle operators  82 , and a vehicle operator identification number  83   a, b . . . n  for each operator. This feature is particularly useful if the vehicle is part of a commercial fleet of vehicles with multiple drivers. Upon turning on the vehicle, the vehicle operator inputs their identification number  71 . This number  71  is compared to the list of authorized operators previously stored in memory  41 . If the input operator identification number  71  matches favorably with one of the authorized operators previously stored in memory  41 , operation of the vehicle is permitted; if not, operation is denied. Optionally, license plate, registration, insurance information and driver&#39;s license information can be additional fields for  FIG. 3F . 
     Use of a vehicle operator identification number  71 , such as a driver&#39;s license, also permits different operators to use the vehicle while retaining their distinct identity and storing information particular to that vehicle operator, similar to a screen name for Internet use such as the America Online (AOL) system. 
     Referring back to  FIG. 3D , the next four fields associated with the sender portion  56  of the header  51  include position  72 , speed  73 , acceleration or deceleration  74 , and direction  75 , which are automatically created from the information obtained from the sender&#39;s GPS receiver  35 . 
     The origination field  76  includes the location of the vehicle when the vehicle was turned on. The destination field  77  includes the destination of the vehicle. This, of course, requires that the destination be input into the mobile unit  16 , such as when a destination is input into a navigation system. It should be understood that the mobile unit operator may override certain fields to ensure that this information is not obtained by other mobile unit operators. For example, the origination  76  and destination fields  77 , which may include personal information that the mobile unit operator does not desire other mobile unit operators to have access to, may include null data such that the sender&#39;s destination and origination will be listed as “not available” to the receiver. The vehicle operator configures their mobile unit  16  as desired to specify which fields should be transmitted with null data. 
     Referring to  FIG. 3E , the fields associated with the receiver portion  56  of the header  51  are shown in greater detail. As discussed with reference to  FIG. 3C , the broadcast or point-to-point field  64  indicates whether the communication is destined for one, multiple, or all operators. If the communication is to be broadcast to all mobile unit operators, the number of addressees field  79  is designated as zero, indicating that all operators will receive the communication. For point-to-point or point-to-multipoint communications, (whereby a plurality of operators may be included within a conversation or communication), the number of addressees field  79  includes the number of operators which will be receiving the communication. For example, if a point-to-point communication is desired, the number of addressees field  79  will include the number one (1) and address field number one  80   a  will be the only field which includes an address. If a point-to-multipoint communication is desired between, for example four additional mobile unit operators, the number of addresses field  79  will include the number four (4) and address fields one through four  80   a - d  will include the addresses of the four receivers to be sent the communication. 
     Once all of the aforementioned fields have been populated with the information, the microprocessor  40  builds each communication packet  50  and forwards the packet  50  to the transceiver  32  for transmission. The packets  50  are preferably transmitted to the base station  14 , and then forwarded to the base station controller  20 . The base station controller  20  routes all of the communication packets  50  to the specified addresses, either to one or more mobile unit operators, one or more outside entities, or both. This routing function is the same as an Internet router, whereby the destination address or addresses are read by the router and the communication packet  50  is forwarded to those addresses. If the communication packet  50  is to be forwarded to multiple addresses or broadcast to all addresses, the base station controller  20  provides such a routing function. 
     The base station controller  20  may also confirm to sender whether or not a signal has been received by the recipient. In an alternative embodiment, each communication may require a confirmation packet be sent from the recipient to the sender to provide the confirmation. Using such an embodiment, the sending mobile unit operator will know whether or not the communication packet  50  has reached its destination. 
     Although the present invention has been explained with reference to a plurality of base stations  14  and a base station controller  20 , the system  10  can also use technology similar to Bluetooth wireless technology. Using technology such as Bluetooth allows mobile units and base stations to communicate through other mobile units and base units (i.e., repeaters). This permits a wireless interconnect between mobile devices, and between mobile devices and their peripherals. The mobile devices can form a secure piconet and communicate among the connected devices. Accordingly, using this technology, mobile units  16  can talk directly to other mobile units  16  without the intervention of the base stations  14  and the base station controller  20 . It is intended that the present invention be used with any type of wireless communication standard including Bluetooth or other wireless or data transmission standard. The particular standard used in transmitting the data is not critical since there are many types of wireless technologies and standards that can be used to transfer information between mobile units  16 . It should be recognized that any of the communications could be encrypted by currently known technologies so that only certain authorized mobile units vehicles can communicate with each other. For example, if two users were communicating with one another and either requested a private conversation, the system can immediately encrypt their communication. 
     As should be understood by those of skill in the art, if the address of the receiver is outside of the system  10  and must be routed via the PSTN  22 , the base station controller  20  formats the communication packet  50  in a format that may be handled by the PSTN  22 . Although the present invention has been explained using a general packet  50  “structure” as illustrated by  FIGS. 3A-3F , this structure is intended to serve as an example of the information to be transmitted by the system  10  in each communication. It is not the intention herein to specify a new communication standard, since the present invention may be utilized with any current or future wireless communication standard. For example, the packets  50  transmitted over the vehicle communication system  10  may use the Internet Protocol (IP) format, such that they may be transmitted seamlessly to any communication system which uses the IP format. The discussion of the particular format and/or conversion to another format for forwarding over the PSTN  22  is outside the scope of the present invention. 
     As shown in  FIGS. 4A and 4B , the memory  41  is used to store information which populates the aforementioned fields. As will be described in greater detail hereinafter with reference to  FIG. 4C , the memory  41  is also used to store other detailed information which may be helpful to the mobile unit operator, other mobile unit operators, the base station controller  20 , or law enforcement agencies. The information stored in memory  41  may originate from a received communication, or may be input into the mobile unit via the AVI  46 . For example, information that is specific to a particular operator, such as those fields illustrated in  FIG. 4C , may be input by the mobile unit operator via the AVI  46 . 
     Referring to  FIG. 4A , one of the uses of the memory  41  is to automatically store a current vehicle activity log  90  and previously entered logs. The vehicle activity log  90  comprises a plurality of fields including the time  90   a , date  90   b , position  90   c , speed  90   d , acceleration/deceleration  90   e,  and direction  90   f  of the vehicle. This log  90  is updated on a periodic basis as determined by the mobile unit operator. For example, private individuals may desire the log  90  to be updated every 15 minutes whereas commercial businesses may require the log  90  to be updated every 15 seconds or even less. It should be realized that the vehicle activity log  90 , if updated on the order of fractions of a second, would be extremely useful during accident reconstruction. 
     Referring to  FIG. 4B , a vehicle communication log  92  is shown. The communication log  92  includes the following fields: the time of the communication  92   a ; the date of the communication  92   b ; an indication of whether the communication was incoming or outgoing  92   c , the address(es) of the communicating entity  92   d ; the priority of the communication  92   e ; an indication of whether the communication is broadcast or point-to-point  92   f ; an indication of whether the communicating entity is within the system or outside the system  92   g ; the security level of the communicating entity  92   h ; an indication of whether the communication is data or voice  92   i ; an indication of whether the communication is information or control  92   j ; and the actual contents of the communication  92   k . The vehicle communication log  92  continually tracks each ongoing communication and stores the contents of the communication in the contents field  92   k  and all of the related information in the remaining fields  92   a - j.    
     Referring to  FIG. 4C , a operator may input via the AVI  46  a plurality of fields related to the specific user and/or vehicle in a user log  105 . One example of a user log  105  is shown in  FIG. 4C  which includes the following fields: registration number  105   a ; insurance company  105   b ; insurance policy number  105   c ; vehicle make  105   d ; vehicle model  105   e ; vehicle color  105   f ; other identifying information  105   g ; vehicle model year  105   h ; EZpass number  105   i ; garage parking account number  105   j ; garage door access code  105   k ; driving record  105   l ; and credit card information  105   m . There is no limit to the number of fields which may be stored in the user log  105 , and all fields can be defined by the mobile unit operator. Since many of these fields include sensitive information, the mobile unit operator may decide not to send any information from the user log  105  and the microprocessor  40 , when constructing the data packets, will place null data in those fields. 
     The procedure utilized by the microprocessor  40  upon receipt of a communication packet  50  is shown in  FIG. 5 . The microprocessor  40  first determines whether the incoming packet  50  is addressed to the specific mobile unit  16 . Accordingly, at step  502 , the microprocessor determines whether the incoming packet is a broadcast, and at step  504 , the microprocessor determines whether the specific address matches the mobile unit address. If either of these determinations is affirmative, the new packet is stored (step  506 ). The microprocessor then determines if there are other communication packets pending for processing (step  508 ). If no other packets are pending, the new packet is processed (step  510 ). If applicable, any packets in the queue are reprioritized in accordance with the priority of each packet (step  512 ) which, in the case where no other packets are pending, would not be necessary. The microprocessor then goes on to reviewing the next packet step ( 514 ). 
     If it has been determined in step  508  that other packets are pending, the priority of all of the pending packets are reviewed (step  516 ) and a determination is made (step  518 ) whether the pending packets have a lower priority than the new packet. If the new packet has a higher priority then the pending packets, the microprocessor halts processing of the pending packet currently being processed (step  520 ), re-stores the pending packet into memory (step  522 ), and proceeds with processing the new packet (step  510 ). 
     If, however, the pending packets do not have a lower priority than the new packet, the microprocessor stores the new packet in a queue with all other pending packets (step  524 ) and continues to process the pending packet (step  526 ). In this manner, the microprocessor  40  is able to process higher priority packets first, and delay processing of lower priority packets to a more appropriate time when the microprocessor has the proper resources. 
     Optionally, even if the microprocessor determines in steps  502  and  504  that the communication is not addressed to the particular mobile unit  16 , either as point-to-point communication or as part of a broadcast communication, the microprocessor may still undertake minimal processing of such packets. This is performed in step  530  whereby a contact log is created. 
     As shown in  FIG. 4D , the contact log  110  may comprise a minimum number of fields such as the time  110   a , date  110   b , address  110   c , color  110   d , make  110   e , and model  110   f  of the vehicle related to the incoming communication packet  50 . The number and type of fields is determined by the mobile unit operator. The payload of the packet may not be stored. The contact log  110  is used by the microprocessor  40  to search for “matches” with other mobile unit operators. Upon request by the mobile unit operator, the microprocessor  40  searches the contact log  110  for any addresses (i.e., sending addresses) that have multiple entries in the log  110 . Once the microprocessor  40  searches the contact log  110  and outputs the addresses which show up on the contact log  110  greater than a certain frequency threshold as set by the mobile unit operator, the operator can determine whether those addresses should be placed in a “commuter” log; which is a list of mobile unit operators as identified by their addresses. 
     This information is provided to the mobile unit operator via the AVI  46 . This permits the operator to identify, either graphically as located on a real-time map or via a list, other mobile unit operators which may be in the vicinity during a certain portion of the day. For example, during a commute to work if other mobile unit operators are typically within the vicinity of the present mobile unit operator during a certain time of day, a “partner log” may be created by each mobile unit operator to permit mobile unit operators to identify, contact, and establish a rapport with other operators. 
     Since the communication packet headers  51  include very detailed information about other mobile units  16 , the system  10  can provide flexibility in contacting other mobile unit operators in the vicinity. For example, if a mobile unit operator observes a vehicle that they would like to establish a private conversation with, the operator may command the mobile unit  16  to “talk” to the blue car. If more than one mobile unit  16  is in a blue car in the vicinity, the microprocessor  40  can filter the commuter log to vehicles having the color blue. If more than one blue car was in the vicinity, the microprocessor  40  presents the make and model of each blue car and requests further instructions. 
     Since all of the detailed information is available in the packet header  51 , the system  10  can provide the speed, direction, and location of the other vehicle in relation to the present vehicle. This information is also important in order to evaluate whether another mobile unit  16  will be available for a conversation having a duration of a minimum length. For example, if a mobile unit operator notes that one of the vehicle operators on his partner log is currently traveling in the vicinity, and the mobile unit operator would like to establish communications with the other mobile unit operator, the system  10  can calculate the duration of a potential conversation based upon the speed and direction of both vehicles and their ultimate destinations, if available. The system  10  can combine that information and advise both mobile unit operators by an audible alarm or a voice message that there is a certain amount of time left in the conversation. The microprocessor  40  can also filter out any mobile units  16  that will not be in the range long enough to establish a reasonable conversation. 
     At step  540 , the microprocessor  40  reviews all incoming communication packets  50  to determine if a particular communication packet  50  originates from an address that is on the vehicle operator&#39;s partner log. As the communication packets  50  are reviewed at step  540 , the mobile unit operator is notified and can decide whether or not they want to establish a communication with the particular mobile unit operator having the address that has compared favorably with the partner log. It should be noted that mobile unit operators can block out transmissions being received from particular individuals or cancel conversations at anytime. Further, mobile unit operators can require information such as drivers license, license plate, and registration to be provided before they allow any other transmissions to be received. 
     Referring to  FIG. 6 , the procedure for processing communication packets  50  by the microprocessor  40  is shown. The microprocessor first parses the packets into separate fields (step  602 ) and stores all of the fields that do not require additional processing (step  604 ). The microprocessor then determines whether a packet includes a data communication by viewing the communication identifier field (step  606 ). If the microprocessor determines that the packet is not carrying a data communication, then it is a voice communication and the microprocessor processes the communication as such (step  608 ). 
     If the packet includes a data communication, the microprocessor must make a determination whether the data communication is a control communication (step  610 ). If it is not a control communication, the data communication is an information communication and it is processed as such (step  612 ). Examples of packets which include information communications include audio, visual, and text files that are downloaded over the Internet, facsimile transmissions, and transmissions from peripheral devices such as laptop computers, handheld devices, and the like. 
     If it has been determined that the packet includes a control communication, the communication is processed as such (step  614 ). The microprocessor compares the control instruction to the security level required (step  616 ). This includes reviewing the security field, including the optional security access code. If the security access code is proper (i.e. authorized), the security level is reviewed and the microprocessor makes a determination of whether the security level is sufficient (step  618 ). If so, the microprocessor performs the control instruction (step  620 ). If not, the microprocessor generates a transmission to the sender of the control instruction that they are not authorized to control the particular mobile unit(step  622 ). The microprocessor  40  also notifies the particular mobile unit operator that a control attempt was made and was unsuccessful. This will alert the mobile unit operator that someone may be utilizing the system for subversive purposes. Optionally, the system may require the mobile unit operator to authorize their vehicle to accept a control instruction, prior to undertaking any control instructions. Once the processing of the packet is performed, the microprocessor goes to the next packet (step  624 ). 
     With respect to the step of performing a control instruction (step  620 ), this may include instructions for the microprocessor to exert electromechanical control over certain aspects of the vehicle&#39;s operation, or may simply include a request for the microprocessor to upload data to the recipient. For example, if the control instruction is a request for the microprocessor to upload information, the microprocessor may upload one or a plurality of the fields shown in  FIG. 4C . 
     In a first example relating to a request for information, if the vehicle is entering a toll booth which utilizes the EZpass system, the control instruction from the transmitting toll booth may request that the EZpass number be transmitted. The microprocessor  40  will transmit the number in the EZpass number field shown in  FIG. 4C  in response thereto. 
     In a second example relating to a request for information, a request for information may occur in a parking garage, gas station, or any other establishment which requires payment from the vehicle operator, such as a drive-in fast-food restaurant. In this example, the vehicle operator will drive up to an ordering kiosk and order the desired food. After the food has been ordered, the driver pulls up to the window whereby the proper food order is presented to the driver. Meanwhile, the restaurant&#39;s communication system sends a communication requesting the credit card information for billing purposes. The information shown in the credit card information field  105   m  of  FIG. 4C  can then be presented to the communication system of the restaurant for payment. Optionally, the mobile unit operator may require that they must first approve of any information being released. Moreover, the communication log for both the fast-food restaurant and the vehicle may store the communication noting the charge amount. For the vehicle it can be a “virtual receipt”. 
     With respect to an instruction which exerts electromechanical control over the vehicle, as shown in  FIG. 2 , the electromechanical interface  44  will interface with those systems of the vehicle over which the mobile unit  16  has control. These systems may include the radio, lights, horn, steering, braking, and any other electromechanical systems of the vehicle. For example, if a mobile unit operator is listening to their favorite radio station and a point-to-point or broadcast communication is received by the mobile unit  16 , the microprocessor  40  through the electromechanical interface  44  will stop the radio, or turn down the volume of the radio, so that a conversation can commence. 
     It should be understood that due to the amount of information set forth in the header  51  of each communication packet  50 , the system  10  provides extreme flexibility in processing and filtering communications. For example, the microprocessor  40  can be programmed to accept only communications from certain makes and models of vehicles. As such, the system  10  set up as part of a Mercedes can be programmed by the manufacturer to be able to talk to only other Mercedes operators. 
     The present invention has the ability to greatly increase safety to drivers and can be a valuable resource for emergency services personnel and law enforcement personnel. For example, emergency vehicles can automatically send signals to warn motorists that an emergency vehicle is approaching. This may supplement the emergency light and siren which are standard on emergency vehicles. Since the packets  50  are prioritized, a communication sent from an emergency vehicle in transit may have the highest priority and can override all other signals having a lower priority. At the scene of an accident, the signal output from an emergency vehicle may, at a slightly lower priority, transmit instructions for avoiding the accident scene and may provide detour instructions. 
     With respect to motor vehicle code enforcement, law enforcement agencies can automatically review the status of a driver, vehicle registration, and insurance and may provide warnings for expired or soon to be expired license, registrations, or insurance policies. 
     If an unauthorized operator has gained access to the vehicle and has not input the proper operator identification number, the microprocessor  40  can transmit an emergency instruction to alert law enforcement agencies that the vehicle has been stolen. The signal sent from the vehicle can automatically include the vehicle&#39;s position, speed, acceleration or deceleration rate, and direction. Law enforcement officials may send an instruction in response to limit the vehicle speed to no greater than 30 miles per hour until the unauthorized operator of the vehicle is apprehended. It should be noted that various fixed units may be strategically placed along highways, major intersections, toll booths, and bridges to monitor traffic and to relay messages back to law enforcement agencies. 
     Another law enforcement use can be to limit speeding of vehicles by notifying law enforcement agencies when a vehicle has exceeded a certain speed limit, e.g., 20% over the speed limit. A law enforcement official, in response, may send an instruction for the vehicle to slow down or risk a traffic citation. This can eliminate the need for “speed traps” and high speed police chases. 
     For public safety applications, specifically located fixed units can warn drivers as the vehicle approaches a traffic light at an intersection that the vehicle must slow down or stop because it will not “make” the green light. The traffic light can make this determination based upon the speed and direction of the mobile unit and the cycle of the traffic light. Other selectively placed fixed units can warn drivers that an intersection or roadway is dangerous for various reasons, such as an accident, a sharp bend, or heavy traffic. The signals output by these locations can be periodically updated as weather and traffic conditions change. In the same manner, vehicles may be warned that a particular vehicle is driving in an erratic manner or that law enforcement officials are currently involved in a pursuit of the vehicle. The warnings to drivers are output through the AVI  46  and may comprise an audible warning, or may comprise a status light such as red, yellow, and green being located on the graphical operator interface of the AVI  46 . In extreme circumstances, selectively placed fixed units may automatically overtake control of a vehicle, for example, during extremely icy conditions to slow the vehicle prior to the danger zone. 
     It should be noted that although the mobile units  16  were described hereinbefore as being located in a vehicle or in a fixed location, they can be incorporated as part of a cellular phone or other portable communication device. 
     The present invention is particularly adaptable for interfacing with the Internet and providing a wealth of information for all mobile unit operators. In one Internet-related embodiment, a website permits storage of information and system administration through the Internet. A system administrator operating at the website or the base station controller  20  monitors and tracks all mobile units  16 . Through the system administrator, the fixed locations are provided with weather and traffic updates or advertisements which are specifically geared to the immediate vicinity of the fixed unit. In this manner, advertisers advertise both on the website and advertise their companies and products as vehicles approach or pass certain properties, stores, or business locations. This also permits stores to provide information to vehicles arriving or leaving the place of business, such as directions for parking or thanking them for their patronage. 
     The system administrator also provides centralized housekeeping functions in order to track all different types of information that are typically a nuisance to vehicle operators, such as the date their registration and insurance policy expire. The system administrator also tracks general vehicle maintenance information and traffic violation records. The tracking of vehicle maintenance can be particularly useful when a recall notification is issued from a manufacturer or even when regularly scheduled maintenance is required. 
     In a second Internet-related embodiment, the system  10  is used to aid law enforcement officals and insurance companies to determine when a traffic accident has occurred and to collect all of the detailed information regarding the traffic accident. This function is centralized in a website such as vehicleaccident.com. When an accident occurs, a signal is automatically sent to all vehicles involved (or in the vicinity) to transmit all pertinent information to vehicleaccident.com. This can include time, speed, direction, acceleration and deceleration, duration of trip, and other pertinent information such as the vehicle maintenance records, traffic citation records, insurance, and registration information. The system  10  permits all of this information to be stored in a centralized location at vehicleaccident.com for later review by law enforcement officials. The system  10  also stores law enforcement officials reports regarding the accident. 
     The insurance industry should benefit by having mobile unit operators agree in advance to accept a fact finding by an officer utilizing all of the information from the mobile units  16 . This avoids costly litigation and subrogation. A mobile unit operator accepting these terms may be permitted special insurance discounts for agreeing to such. 
     In another embodiment, the system can provide mobile units that does not include a GPS unit. It can be similar to portable phone(s) operating on the same frequency(s). If a user tunes their radio to a particular station, they can receive a transmission through their car stereo. The mobile unit, in this instance, can have the microphone inside of it so a user can speak “hands free”. This embodiment allows the mobile unit to beep (or voice activate) if another user comes within range, advising both mobile units that they have someone they can talk to. The mobile unit detects another mobile unit by actually receiving the signal of the other mobile unit. Accordingly, positioning of either mobile unit is not required. 
     Although the invention has been described in part by making detailed reference to example embodiments, such detail is intended to be instructive rather than restrictive. It will be appreciated by those skilled in the art that many variations may be made in the structure and mode of operation without departing from the spirit and scope of the invention as disclosed in the teachings herein.