Abstract:
A system, apparatus, method and computer program product to obtain comprehensive vehicle radio listener statistics based on parameters such as radio status (e.g., on/off status and CD/Tape/AM/FM setting), radio volume, station preset information, current frequency setting (i.e., station identification), and Global Positioning Satellite (GPS) system coordinates is disclosed. A vehicle-mounted field unit for collecting and transmitting such parameters to a base station is also disclosed. The system monitors and stores all events related to the occupants&#39; interaction with the vehicle&#39;s radio, including automatic detection of the selected radio station through a speaker port. The stored data is then transmitted to a base station&#39;s central collection computer for immediate compilation and analysis. The system is capable of producing detailed reports containing error-free, unbiased, audience measurement statistics which can be made available to subscribers such as broadcasters, corporate advertisers, advertising agencies and the like.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is a division of U.S. application Ser. No. 09/996,770 filed Nov. 30, 2001 which claims priority from U.S. Provisional Application Ser. No. 60/276,489, filed Mar. 19, 2001, U.S. Provisional Application Ser. No. 60/299,402, filed Jun. 19, 2001, and U.S. Provisional Application Ser. No. 60/299,787, filed Jun. 22, 2001. The entirety of each of these provisional applications is incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates generally to computer information gathering and processing systems, and more particularly to a computer-based system and apparatus for monitoring, recording, and reporting vehicle radio listener statistics.  
         [0004]     2. Related Art  
         [0005]     In today&#39;s competitive business environment, it is common for advertisers, marketers, business concerns and the like to desire to gauge the likes and dislikes of the general public. It is important to successful business endeavors to have some measure of the public&#39;s reaction to a business concern&#39;s products and services. This fundamental principle of business is no less true in the radio broadcasting industry. That is, in the radio world, monitoring broadcasts and determining the demographics of listeners is essential to running a successful broadcasting business. Radio advertising executives exert a significant amount of energy searching for more detailed information to guide their marketing investment, which in 1999 exceeded $17.6 billion dollars. Also, station owners are in the same search for information to guide their programming and on-air talent scheduling.  
         [0006]     Arbitron, Inc. of New York, N.Y. currently offers a radio listener statistical gathering and reporting service (i.e., a rating service). Arbitron rates broadcasts based on the listening audience tuned into a particular station on a quarterly basis. This rating, unlike rating services for television broadcast done by Nielsen Media Research, Inc. of New York, N.Y., is not done in real time. Over the past fifty years, the conventional (Arbitron) method of providing these statistics is from a network of paper diaries maintained by thousands of listeners in markets across the United States.  
         [0007]     More specifically, the Arbitron process collects paper questionnaires via random sampling of a market. Thus, for a given market, a certain percentage of the population is randomly selected and called. The calls are generated by random number dialing. Those persons who are contacted via the telephone are then asked if they are willing to participate in the Arbitron diary process. If the person agrees, Arbitron then sends that person a paper diary. The diary consists of three types of questions: (1) What did you listen to? (2) When did you listen to it? (3) Where were you when you listened to it? The participants are asked to collect this information and write it down in the provided diary over a seven-day period. At the end of that seven-day period, the diary is sent back to Arbitron. This process is repeated until a statistically relevant number of diaries are collected in the given market.  
         [0008]     Many in the radio industry view this system as outdated and inadequate. This is because the statistical output lacks depth and the months-long lag time for receiving reports. The process is also vulnerable to bias and fraud. That is, if a participant prefers a specific station, they (intentionally or unintentionally) may fill the diary in a way that favors that particularly radio station. Further, if a person with fraudulent intentions obtains one or more diaries and skews them towards a particular station, this compromises the statistical integrity of the process. Despite these current limitations, in 1999, over $169 million dollars was spent by various broadcasters and other subscribers for listener statistics because alternative rating sources are not available.  
         [0009]     In an attempt to overcome the above-described shortcomings, Arbitron has recently developed and is currently testing a “Portable People Meter” (PPM) system. The PPM is a pager-sized device that is worn or carried by survey participants throughout the day to collect radio listening statistics. The PPM, however, still faces several shortcomings such as lack of in-depth information recorded, contaminated data due to stray broadcast signals, expense of installing PPM signal embedding devices in multiple broadcast points, and skewed data due to visual presence of the PPM device on survey participants. Another shortcoming is that the PPM system&#39;s statistical integrity depends on survey participants actually wearing, activating, and periodically returning the PPM device to a base cradle to upload its stored information and re-charge its batteries.  
         [0010]     Further, apparatus to monitor the selected radio station within a vehicle are known. These apparatus typically employ one of two know methods for detecting the tuned radio station. One method, known as a “sniffer” method, involves tuning the receiver to the local radio phase lock loop (PLL) and then calculating the tuned frequency by knowing the intermediate frequency (IF). The second method, known as a “comparator” method, involves comparing output audio signals from the speaker port to a (known) reference audio signal (i.e., a pre-selected radio station). Then, if the two signals are in phase, the tuned radio station can be identified. Both methods, however, suffer from shortcomings.  
         [0011]     The sniffer method&#39;s shortcomings include the fact that different radio manufacturers have different IF frequencies (i.e., there are no standards for IF frequencies), and that some radio manufacturers do not have local PLL for AM radio stations, which makes them impossible to measure. The comparator method&#39;s shortcomings include the fact that it takes too much time (i.e., typically ten seconds or more) to find the selected station—which is disadvantageous if the vehicle&#39;s occupants have subsequently changed stations again.  
         [0012]     A system that comprehensively monitors broadcasts and determines the demographics of listeners on a real time, or near real time, basis has not previously existed. Nor has an apparatus that automatically detects the selected radio station through a speaker port as part of that comprehensive system. Therefore, given the above, what is needed is a real-time system for obtaining, monitoring, recording and reporting comprehensive radio listener statistics which includes an apparatus that automatically detects the selected radio station.  
       SUMMARY OF THE INVENTION  
       [0013]     The present invention meets the above-identified needs by providing a system, apparatus, method and computer program product for obtaining, monitoring, recording and reporting comprehensive radio listener statistics.  
         [0014]     The present invention collects radio listener statistics from vehicle radios via a non-obtrusive, vehicle-mounted device. This device monitors and stores all events and parameters related to the vehicle&#39;s occupants interactions with the radio. Parameters monitored include, for example, radio status (e.g., on/off status and CD/Tape/AM/FM setting), radio volume (0%-100%), station preset information, current frequency setting (i.e., station identification), and Global Positioning Satellite (GPS) system coordinates. Each time a monitored parameter changes (e.g., station is changed, volume is lowered, etc.), the event is dated, time stamped and stored in the vehicle-mounted device for later transmission. The stored data is then transmitted periodically, via existing wireless networks, to a central collection computer (i.e., base station server) for immediate compilation and analysis. Results are then made available to users, including, for example, broadcasters, corporate advertisers, and advertising agencies.  
         [0015]     The system also includes an apparatus within the vehicle-mounted device that automatically detects the selected radio station. In an embodiment, the apparatus uses a modulator to inject AM/FM code modulated carrier signals through a directional coupler connected to the vehicle radio. The directional coupler is inserted between the radio and the vehicle&#39;s antenna. A controller then recovers AM/FM code from the speaker through a band pass filter.  
         [0016]     An advantage of the present invention is that it allows continuous parameter sampling of all vehicle-mounted field units within a specified market in order to provide more statistically accurate results.  
         [0017]     Another advantage of the present invention is that it implements an unbiased and error-free data collection method that is not dependent on participant (i.e., the vehicle&#39;s occupants) memory recall, and it is not subject to fraud.  
         [0018]     Another advantage of the present invention is that it provides precise data collection which allows specific broadcast events to be monitored. For example, listener reaction to specific broadcast segments can be measured by monitoring volume changes and fallout station information.  
         [0019]     Yet another advantage of the present invention is that it provides listener reaction to specific on-air events that can be made available to advertisers and business concerns shortly after the broadcast or marketing campaign is aired. Further, custom surveys can be generated upon the request of users of the system.  
         [0020]     Yet another advantage of the present invention is that it utilizes GPS information, which allows users of the system to get a more comprehensive understanding of the listening public.  
         [0021]     Further features and advantages of the invention as well as the structure and operation of various embodiments of the present invention are described in detail below with reference to the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]     The features and advantages of the present invention will become more apparent from the detailed description set forth below when taken in conjunction with the drawings in which like reference numbers indicate identical or functionally similar elements. Additionally, the left-most digit of a reference number identifies the drawing in which the reference number first appears.  
         [0023]      FIG. 1  is a block diagram illustrating the system architecture of an embodiment of the present invention, showing connectivity among the various components;  
         [0024]      FIG. 2  is a block diagram of the physical architecture of a vehicle-mounted field unit according to an embodiment of the present invention;  
         [0025]      FIG. 3  is a detailed block diagram illustrating the system architecture of an embodiment of the present invention, showing communications among the various components;  
         [0026]     FIGS.  4 A-B are windows or screen shots of exemplary reports generated by the graphical user interface of the present invention;  
         [0027]      FIG. 5  is an Entity-Relationship diagram of example relational database tables according to an embodiment of present invention;  
         [0028]      FIG. 6  is a block diagram of an exemplary computer system useful for implementing the present invention;  
         [0029]      FIG. 7  is a block diagram of an apparatus that automatically detects the tuned radio station in one embodiment of the present invention; and  
         [0030]      FIG. 8  is a flowchart illustrating the automatic radio station detection process according to an embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION  
       [0031]     I. Overview  
         [0032]     The present invention relates to a system, apparatus, method and computer program product for obtaining, monitoring, recording and reporting comprehensive radio listener statistics.  
         [0033]     In an embodiment of the present invention, a service provider organization provides and allows access, perhaps on a subscriber fee or pay-per-use basis, to a tool that obtains, monitors, records and reports comprehensive vehicle radio listener statistics via the global Internet. That is, the service provider would provide the hardware (e.g., servers) and software (e.g., database) infrastructure, application software, customer support, and billing mechanism to allow its customers (e.g., broadcasters, corporate advertisers, advertising agencies and the like) to receive reports of, for example, listener reaction to specific on-air events or segments. The tool would be used by subscribers to obtain both real-time and historical information, characteristics, and trend analysis to make marketing and advertising decisions.  
         [0034]     The level of detail collected by the present invention, which has not been seen in any conventional systems, allows broadcasters and advertisers the ability to accurately measure the effectiveness of new marketing campaigns, radio personalities, or other on-air broadcasts. Advertisers can know, within days, for example, how many listeners heard their advertisements, how many turned the station seconds into the airing, and how many turned the volume up to hear a particular broadcast segment. Stations will be able to see listener reactions to new on-air talents and broadcast segments identifying events that cause listeners to migrate to competitors. In each case, the reported statistics provide the ability to adjust and refine on-air content contributing to its overall effectiveness and value by reducing listener chum.  
         [0035]     In an embodiment of the present invention, the service provider would provide a World Wide Web site where a subscriber, using a computer and Web browser software, can remotely view and receive comprehensive vehicle radio listener statistics.  
         [0036]     In an alternate embodiment, the tool that obtains, monitors, records and reports comprehensive vehicle radio listener statistics may reside, instead of on the global Internet, locally on proprietary equipment owned by a subscriber (i.e., broadcasters, corporate advertisers, advertising agencies and the like) as a stand alone system software application.  
         [0037]     The present invention is described in terms of the above examples. This is for convenience only and is not intended to limit the application of the present invention. In fact, after reading the following description, it will be apparent to one skilled in the relevant art(s) how to implement the following invention in alternative embodiments. For example, a service provider may utilize the existing wireless network&#39;s two-way communications capabilities in order to communicate with the vehicle and its occupants. This would allow the offering of ancillary services with the ability to launch mobile commerce, instant polling and (emergency) vehicle services utilizing the capabilities of the installed vehicle-mounted field units as described herein.  
         [0038]     The terms “user,” “subscriber,” “customer,” “company,” “business concern,” “broadcaster,” “corporate advertiser,” “advertising agency,” and the plural form of these terms are used interchangeably throughout herein to refer to those who would access, use, and/or benefit from the tool that the present invention provides for obtaining, monitoring, recording and reporting comprehensive radio listener statistics.  
         [0039]     II. System Architecture  
         [0040]     Referring to  FIG. 1 , a block diagram illustrating the physical architecture of a vehicle radio listener statistics (“VRLS”) system  100 , according to an embodiment of the present invention, showing network connectivity among the various components, is shown. Such VRLS system  100  would cover a specific market area (e.g., metropolitan statistical area (MSA)) in which the service provider offers its services.  
         [0041]     VRLS system  100  includes a plurality of users  102  (e.g., broadcasters, corporate advertisers, advertising agencies, and the like) which would access to system  100  using a personal computer (PC) (e.g., an IBM™ or compatible PC workstation running the Microsoft.RTM. Windows 95/98™ or Windows NT™ operating system, Macintosh.RTM. computer running the Mac.RTM. OS operating system, or the like), running a commercially available Web browser. (For simplicity,  FIG. 1  shows only one user  102 .) The users  102  would connect to the parts (i.e., infrastructure) of VRLS system  100  which are provided by the VRLS service provider via the global Internet  104 .  
         [0042]     In alternative embodiments, users  102  may access VRLS system  100  using any processing device including, but not limited to, a desktop computer, laptop, palmtop, workstation, set-top box, personal digital assistant (PDA), and the like.  
         [0043]     VRLS system  100  also includes a base station  110  which contains a base station server  106 . Server  106  is the “back-bone” (i.e., VRLS processing) of the present invention. It provides the “front-end” for VRLS system  100 . That is, server  106  contains a Web server process running at a Web site which sends out Web pages in response to Hypertext Transfer Protocol (HTTP) requests from remote browsers (i.e., subscribers  102  of the VRLS service provider). More specifically, it provides a graphical user interface (GUI) “front-end” screens to users  102  of VRLS system  100  in the form of Web pages. These Web pages, when sent to the subscriber&#39;s PC (or the like), would result in GUI screens being displayed.  
         [0044]     In an embodiment of the present invention, server  106  is a Sun or NT workstation having access to a repository database implemented with the Oracle 8i RDBMS (relational database management server) software. The database is the central store for all information within VRLS system  100  (e.g., executable code, subscriber information such as login names, passwords, etc., and vehicle and demographics related data).  
         [0045]     VRLS system  100  also includes a plurality of vehicles each with a vehicle-mounted field unit  108  which is explained in more detail below. (For simplicity,  FIG. 1  shows only one vehicle having a field unit  108 .) In an embodiment of the present invention, the vehicle-mounted field units  108  have access to the vehicle&#39;s radio in order to monitor, record, store and transmit the listener parameters as explained herein.  
         [0046]     VRLS system  100  also includes a plurality of radio towers  116  from which each broadcaster in the market area transmits their signals on a unique frequency (i.e., their unique station identification). As will be apparent to one skilled in the relevant art(s), these signals are received by vehicle radios and thus, may be monitored by the vehicle-mounted field units  108  as described herein. Also received by the vehicle-mounted field units  108  are signals from the Global Positioning Satellite (GPS) constellation  112 . As is well-known in the relevant art(s), the GPS constellation system  112  operationally consists of 24 satellites that provide global coverage. For any given reading, four satellites are required to compute the three dimensions of position (X, Y, and Z) and time. (For simplicity, however,  FIG. 1  shows only one GPS satellite.) VRLS system  100  also includes a wireless communications infrastructure which, in one embodiment, consist of one or more wireless towers  114 . (For simplicity,  FIG. 1  shows only one tower  114 .) As will be apparent to one skilled in the relevant art(s) after reading the description herein, the vehicle-mounted field units  108  are configured for the specific means of wireless mobile communications employed within the market area in which VRLS system  100  operates (e.g., satellite or terrestrial wireless). This allows the service provider to take advantage of existing wireless communication networks to transfer information collected by the field units  108  to base station  110 .  
         [0047]     As will be appreciated by one skilled in the relevant art(s) after reading the description herein, a service provider can replicate VRLS system  100  in each market area or MSA in which they offer services. Thus, several base stations  110  may be connected via a network proprietary to the service provider in order to produce vehicle radio statistics over several market areas.  
         [0048]     Referring to  FIG. 2 , a block diagram  200  of the physical architecture of a vehicle-mounted field unit  108  and its connection to a vehicle according to an embodiment of the present invention is shown. The vehicle-mounted field unit  108  consists of a circuit board equipped with a radio station detection unit (SDU)  210 , GPS receiver  212 , and a power supply  214 . In an embodiment, unit  108  is non-obtrusive, has dimensions approximately that of a deck of playing cards and is operable in the temperature range of −40.degree. C. to +85.degree. C. In an embodiment, unit  108  can reside either under the vehicle&#39;s dashboard or in the trunk and draw power from the vehicle&#39;s battery  208  through its power supply  214 .  
         [0049]     In an embodiment, SDU  210  is connected to the vehicle&#39;s radio  204  through connections between the antenna  202  and speaker  206  of vehicle radio  204  as shown in diagram  200 . As will be apparent to one skilled in the relevant art(s), vehicle-mounted field unit  108  would also include an internal clock for date and time stamps and software code logic to drive the functionality described herein (i.e., interpretation of input data from the radio, speaker, and information sent from base station  110 , and data preparation and compression of output data for transmission to base station  110 ). In one embodiment, such internal clock would be part of a processor residing on SDU  210  which is explained in more detail below.  
         [0050]     As will be appreciated by one skilled in the relevant art(s) after reading the description herein, once a potential candidate is identified by the service provider, a vehicle-mounted field unit  108  will need to installed in their vehicle (whether it be a passenger, personal or commercial vehicle, van, truck, light truck, RV, etc.). Information such as each unit&#39;s electronic serial number and corresponding participant demographic information, as well as the total number of units installed would then be kept by the service provider to be utilized in the statistical reporting process as described herein.  
         [0051]     As mentioned above, in an embodiment of the present invention, server  106  has access to a repository database that is the central store for all information within VRLS system  100 . Referring to  FIG. 5 , an Entity-Relationship diagram  500  of example relational database tables, according to an embodiment of present invention, is shown. The tables of diagram  500  contain symbols denoting the minimum and maximum cardinality of the relationship of the entities (i.e., tables) to one another, such as one-to-many (1.fwdarw . . . infin.), or a many-to-one (.infin . . . fwdarw.1). As will be apparent to one skilled in the relevant art(s), the specific fields (and thus, tables) used within VRLS system  100  may vary depending on such characteristics as the type of statistics users  102  desire to be reported, etc.  
         [0052]     More detailed descriptions of VRLS system  100  components, as well their functionality, are provided below.  
         [0053]     III. System Communications and Operation  
         [0054]      FIG. 3  illustrates a detailed block diagram of the architecture of VRLS system  100 , and shows the communications among the various components.  
         [0055]     In an embodiment of VRLS system  100 , vehicle-mounted field unit  108  has four points of connection to the vehicle. The first connection is to the vehicle&#39;s radio  204  via SDU  210  to monitor the activity parameters (i.e., frequency setting, on/off status, AM/FM/Cassette/CD setting, volume, etc.). In one embodiment of the present invention, SDU  210  can monitor the frequency setting of the radio  204  via the known sniffer or comparator methods or the novel method described below with reference to  FIGS. 7 and 8 .  
         [0056]     The second connection from the vehicle-mounted field unit  108  is to the vehicle&#39;s speaker  206  via SDU  210 . This allows volume adjustments to be monitored. In an alternate embodiment, this second connection will give the service provider the ability to present packet information in the form of verbal announcements to the vehicle&#39;s occupants (e.g., traffic and weather information).  
         [0057]     The third connection from the vehicle-mounted field unit  108  is to the vehicle&#39;s antenna  202  in order to connect to the existing communications network (e.g., wireless towers  114 ). In an alternate embodiment, if the vehicle&#39;s antenna is unable to provide two-way functionality, an external wireless antenna will have to be mounted to the vehicle in order to connect to the existing communications network (e.g., wireless towers  114   a - c ).  
         [0058]     The fourth and final connection from the vehicle-mounted field unit  108  is to the vehicle&#39;s power source (i.e., battery  208 ). As discussed above with reference to  FIG. 2 , the vehicle-mounted field unit  108  also contains receiver  212  to communicate with the GPS system  112  (not shown in  FIG. 3 ).  
         [0059]     The base station  110  serves as market specific data gatekeepers. That is, subscribers  102  are able to pull information from specific, multiple or all markets at any give time for immediate analysis. The distributed computing model has no single point of complete system failure, thus minimizing system  100  downtime. Base station  110  contains a transmitter/receiver  316  in order to connect to the existing communications network (e.g., wireless towers  114   a - c ).  
         [0060]     In an embodiment of the present invention, SDU  210  includes a transceiver that takes advantage of existing wireless communication networks to transfer information collected by the field unit  108  and stored in its memory to base station server  106 . Thus, such a transceiver would be compatible with wireless mobile communications standards such as satellite communications, code division multiple access (CDMA), time division multiple access (TDMA), the Bluetooth.RTM. wireless standard and the like as shown in  FIG. 3 .  
         [0061]     As will be apparent to one skilled in the relevant art(s), all of components inside of base station  110  are connected and communicate via a wide or local area network (WAN or LAN) with a hub  318  running a secure communications protocol (e.g., secure sockets layer (SSL)) and having a connection to the Internet (and thus, WWW)  104 .  
         [0062]     In an embodiment, base station server  106  is distributed according to specific tasks. While two separate servers  106  (i.e., server  106   a  for data collection and server  106   b  for report generation) are shown in  FIG. 3  for ease of explanation, it will be apparent to one skilled in the relevant art(s) that VRLS system  100  may utilize servers (and databases) physically located on one or more computers. Each server  106  contains software code logic that is responsible for handling tasks such as data interpretation, statistics processing, data preparation and compression for output to field units  108 , and report generation for output to users  102  or printer  314 , respectively.  
         [0063]     In one embodiment of the present invention, the overall flow and operation of VRLS system  100  is as follows: After a predetermined time interval (e.g., a time interval measured in days, hours, minutes, etc.) of monitoring broadcasts and GPS coordinates, the vehicle-mounted field unit  108  prepares all stored data for transmission. The packet of information is sent via a wireless link  114  to base station  110  through base station transceiver  316 . There, the data is processed (i.e., compiled and analyzed) by server  106   a . Once this process is complete, a confirmation is sent back through the communications network to the field unit  108 . The information is then made ready for distribution (i.e., reports are generated by server  106   b ) to subscribers  102 . As will be appreciated by one skilled in the relevant art(s) after reading the description herein, the field unit  108  may be configured to transmit data collected from the vehicle with varying frequency (e.g., once every 5 minutes, twice a day, etc.). Such frequency would depend on factors such as the size of the memory on unit  108 , bandwidth of the existing communications network, needs of the subscribers  102  and the like.  
         [0064]     FIGS.  4 A-B are windows or screen shots of exemplary reports generated by the graphical user interface of the present invention for a particular radio station (e.g., 94.5 FM) in a particular market (Atlanta, Ga.). It should be understood that the screens shown herein, which highlight the functionality of VRLS system  100 , are presented for example purposes only. The software architecture (and thus, GUI screens) of the present invention are sufficiently flexible and configurable such that users  102  may receive reports (and navigate through in a manner) other than those shown in FIGS.  4 A-B.  
         [0065]     As mentioned above, a service provider may utilize the existing wireless network&#39;s two-way communications capabilities in order to communicate with the vehicle and its occupants, thus offering instant polling capabilities. More specifically, in an embodiment, the field unit  108  contains voice recognition components and a microphone that allows the vehicle occupants to keep both hands on the steering wheel while communicating with field unit  108 . A verbal command key such as “Service Provider Poll” can be used to alert vehicle occupants (survey participants) that the unit  108  is now functioning as an instant polling mechanism. During a poll, participants can then answer questions using simple canned responses such as: 
        A, B, C, D, or E;     1 through 5 (i.e., Worst to Best); and     Yes or No.        
 
         [0069]     As will be appreciated by one skilled in the relevant art(s) after reading the description herein, vehicle owners who are chosen to have field units  108  installed for purposes of rating radio stations will represent a sensible scientific sample. Thus, such vehicle occupants are reflective of local communities, metro areas, regions or even an entire nation. The instant polling embodiment of the present invention is thus a natural extension of the functionality described above with respect to compiling and analyzing radio listener statistics. In the same manner, polls can be targeted to specific geographic areas, demographic profiles or any combination of these.  
         [0070]     IV. Radio Station Detection Apparatus  
         [0071]     As will be appreciated by those skilled in the relevant art(s), automatically detecting the selected radio station within the vehicle is an integral part of VRLS system  100 . Such an apparatus and method, in one embodiment of the present invention, are now described.  
         [0072]     Referring to  FIG. 7 , a detailed block diagram  700  of a station detection unit (SDU)  210  within vehicle-mounted field unit  108 , according to an embodiment of the present invention, is shown. In such an embodiment, SDU  210  is an apparatus that automatically detects the selected radio station through a speaker port.  
         [0073]     As shown in diagram  700 , a directional coupler  702  is connected between the vehicle radio  204  and the radio antenna  202 . In one embodiment, directional coupler  702  is a model ADC-10-1R coupler available from Mini-Circuit, Inc. of Brooklyn, N.Y. The radio  204  is connected to the radio speaker  206 .  
         [0074]     A modulator  720  is connected to the directional coupler  702 . The modular includes an AM synthesizer  708 , AM code modulator  710 , FM synthesizer  712 , and FM code modulator  714 . Modulator  720  also includes a first switch  716  (labeled as “SW1” in diagram  700 ) and a second switch  718  (labeled as “SW2” in diagram  700 ). Switch  716  is used to define the timing for the injecting of radio signals into radio  204  by the modulator  720  through the coupled port of directional coupler  702 . Switch  718  is used to select between the two modulator types (i.e., AM or FM).  
         [0075]     A microprocessor  730  is connected to the modulator  720 . Microprocessor  730  contains hardware and software code logic that controls the automatic selected radio station detection process by loading synthesizers  708  and  712 , creating the modulation patterns and controlling switches  716  and  718 . Microprocessor  730  also checks the correlation between the test signal injected into the radio  204  by SDU  210  and the signal recovered from speaker  206 .  
         [0076]     Microprocessor  730  also contains memory (not shown in diagram  700 ) where a pre-determined list of radio stations is stored. That is, in an embodiment, microprocessor  730  would be pre-programmed to store a list of all (e.g., 50-100) FM and AM stations within the metropolitan area or MSA in which the vehicle having on-board unit  108  were operated and the services of VRLS system  100  were offered.  
         [0077]     In an alternate embodiment, microprocessor  730  would be programmed to store a list of all FM and AM stations within the relevant metropolitan area or MSA “on the fly.” In such an embodiment, on-board unit  108  would contain an additional (auxiliary) tuner (e.g., a AD608 tuner available from Analog Devices, Inc. of Norwood, Mass.) coupled to antenna  202  via an additional directional coupler that would scan the entire FM and AM broadcast ranges once every pre-determined time interval (e.g., once every hour) at a pre-determined frequency interval (e.g., every 100-200 kHz) and measure the radio signal strength indicator (RSSI) to obtain a list of all FM and AM stations within the relevant metropolitan area or MSA. In such an embodiment, a service provider would be able to accommodate a vehicle having on-board unit  108  and traveling between two or more metropolitan areas or MSAs where services of a VRLS system  100  are offered.  
         [0078]     The memory within microprocessor  730  also stores all the logged, untransmitted information (e.g., time, tuned station, GPS coordinates and any other monitored parameters) collected SDU  210  and needed for the statistical reporting purposes of VRLS system  100  as described herein.  
         [0079]     In general operation, signals from the speaker output are detected and sent through a band pass filter (BPF)  722  which cuts off low and high frequency components (e.g., components greater than 10 kHz and lower than 1 kHz), including DC fluctuations caused by frequency hopping transitions, and then directs the signal to both a null detector  724  and a code correlator  726 . First, DSP processor  728  looks for an audio mute from null detector  724 —implemented with a comparator in one embodiment, which typically corresponds to the changing of the station on the radio  204 . Once it has been determined that the tuned station on radio  204  has been changed, DSP processor  728  injects a coded signal into the radio  204  via the directional coupler  702  and then makes a decision about code concurrence of the received signal at the code correlator  726 . In the case of positive code concurrence, DSP processor  728  successfully stops the automatic detection process as explained in more detail below with reference to  FIG. 8 .  
         [0080]     V. Automatic Selected Radio Station Detection Method  
         [0081]     Referring to  FIG. 8 , a flowchart illustrating an automatic radio station detection process  800 , utilizing SDU  210  of diagram  700  according to an embodiment of the present invention, is shown. Process  800  begins at step  802  with control passing immediately to step  804 .  
         [0082]     In step  804 , a main loop is entered in which SDU  210  begins the automatic radio detection process as part of the larger, comprehensive VRLS system  100 . In step  804 , SDU  210  samples the output of radio  204  going to speaker  206  once every pre-determined time interval. In an embodiment of the present invention, such pre-determined time interval is one millisecond (i.e., one sample every 1 millisecond).  
         [0083]     In step  806 , SDU  210  determines if the last x samples detected from the output of radio  204  are “zero” values (i.e., whether the audio voltage measurements taken by null detector  724  are so low that they approach zero). If not, this indicates that the vehicle&#39;s radio is continuously listening to a particular station and no status change has occurred. Thus, process  800  returns to the start of the main loop (i.e., step  804 ). If so, this indicates that there has been a pause (i.e., silence) in output directed to speaker  206 . Process  800  then proceeds to step  808 .  
         [0084]     In step  808 , it is determined if an additional y samples detected from the output of radio  204  are zero values. That is, SDU  210  determines whether the additional pause of output from radio  204  (x+y) is greater than a pre-determined threshold (N). If so, this indicates that radio  204  was most likely turned off and process  800  returns to the start of the main loop (i.e., step  804 ). If not, this indicates that the vehicle&#39;s occupants most likely changed the radio station and process  800  proceeds to step  810 .  
         [0085]     As shown in  FIG. 7 , steps  804 - 808  are accomplished by microprocessor  730  receiving signals from the output of radio  204  going to speaker  206 . The signals pass through the BPF  722  and are read by the null detector  724  within microprocessor  730 . As will be appreciated by one skilled in the relevant art(s) after reading the description herein, values x, y and N are pre-determined and, in one embodiment, are set to 250, 800, and 1050, respectively (assuming a 1 millisecond sampling rate in step  804 ). That is, values x, y and N may vary and be adjusted during installation of unit  108  according to such factors as the make (manufacturer) and model of radio  204 .  
         [0086]     Returning to process  800 , in steps  810 - 812 , SDU  210  performs a tuning pause validation routine. That is, a test signal representing the last known station which the vehicle&#39;s radio was known to be tuned to is injected into the radio  204  via the directional coupler  702 . Then, code correlator  726  determines whether the signal received from the output of radio  204  going to speaker  206  matches this test signal. If so, this indicates that the original pause detected in steps  806 - 808  was a result of station programming error, sound silence or the like, and the vehicle&#39;s occupants have not in fact changed the tuned radio station. Thus, process  800  returns to the start of the main loop (i.e., step  804 ). If not, this indicates that the original pause detected in steps  806 - 808  is a valid tuning pause (i.e., it was in fact a result of the vehicle&#39;s occupants actually changing the tuned radio station causing the consecutive x “zero” values). (Steps  810  and  812  are similar to, and explained in more detail below with reference to steps  816  and  818 , respectively.) When step  812  determines that the vehicle&#39;s occupants have actually changed the tuned radio station, process  800  enters a detection sub-loop (i.e., steps  814 - 820 ) which identifies the new tuned station.  
         [0087]     In step  814 , the next station to be tested is selected. That is, one of the previously-identified stations stored in the memory of microprocessor  730  is selected to determine if it is the new radio station that the vehicle&#39;s occupants have tuned to. In an embodiment, the previously identified stations stored in the memory of microprocessor  730  are selected in order of frequency (e.g., lowest-to-highest or highest-to-lowest). Further, in an embodiment, if the previously tuned radio station was an FM station, step  814  selects the from all of the previously identified FM stations stored in the memory of microprocessor  730  before selecting any previously identified and stored AM stations. Conversely, if the previously tuned radio station was an AM station, step  814  selects from all of the previously identified AM stations stored in the memory of microprocessor  730  before selecting any previously identified and stored FM stations.  
         [0088]     In step  816 , a modulation frequency signal with a predetermined test (binary) code is injected into the carrier frequency signal corresponding to the station selected in step  814 . This resulting test signal is then sent by modulator  720  to radio  204  through directional coupler  702 . In the FM case, step  816  is accomplished by code logic in DSP processor  728  directing frequency code modulator  714  and FM synthesizer  712  to tune to the frequency of the test station selected in step  814 . In the AM case, step  816  is accomplished by code logic in DSP processor  728  directing amplitude code modulator  710  and AM synthesizer  708  to tune to frequency of the test station selected in step  814 . Then, in either the FM or AM cases, DSP processor  728  selects the position of switch  718  (AM or FM depending in the test radio station selection made in step  814 ), and closes switch  716  to allow the injection of the test signal into radio  204 .  
         [0089]     In step  818 , an analysis of the radio&#39;s response to the test signal is performed. The signal received from the output of radio  204  to speaker  206  passes through BPF  722  and is read by the code correlator  722  within microprocessor  730 . If DSP processor  728  determines there is not positive code concurrence (i.e., the selected test station is not the new station the vehicle&#39;s occupants have tuned to), then process  800  proceeds to step  820 .  
         [0090]     In step  820 , it is determined whether all the previously identified stations stored in the memory of microprocessor  730  have already been tested. If not, process  800  returns to step  814  (i.e., the start of the detection sub-loop) and the next previously identified station stored in the memory of microprocessor  730  is chosen. If so, this indicates that all the known stations previously identified and stored in the memory of microprocessor  730  have been tested and the currently tuned station has not been identified. In an embodiment, this event may simply be logged by SDU  210  for eventual reporting to base station  110 , or the list of stations may be tried again before logging the event for reporting. In an alternate embodiment, this may indicate that radio  204  is in CD or Tape mode. Process  800  then returns to the start of the main loop (i.e., step  804 ). As will be appreciated by one skilled in the relevant art(s) after reading the description herein, if radio  204  is in the CD or Tape mode, process  800  (i.e., null detector  724  performing steps  804 - 810 ) would detect a pause during every track change thereby monitoring for a change back to the AM/FM mode.  
         [0091]     Returning to step  818 , if DSP processor  728  determines there is positive code concurrence (i.e., the selected test station is actually the new station the vehicle&#39;s occupants have tuned to), then process  800  proceeds to step  822 . In an embodiment, positive code concurrence occurs when the signal received by microprocessor  730  (phase-independently) matches, within a pre-determined threshold to account for noise, the test signal injected into radio  204  by modulator  720  (in step  816 ). More specifically, code concurrence occurs when the coded modulation frequency signal of the test signal is recoverable—within the threshold—from the signal received from the speaker output of radio  204 . In an embodiment, such threshold would equal a value of at least 90%.  
         [0092]     In step  822 , the identity of the new tuned radio station, the time, GPS coordinates, and any other logged, untransmitted information needed for the statistical reporting purposes of VRLS system  100  as described herein, are recorded and stored in the memory of microprocessor  730 . Then, as indicated by step  822 , process  800  returns to the start of the main loop (i.e., step  804 ).  
         [0093]     In an embodiment of the present invention, GPS receiver  212  located in vehicle-mounted field unit  108  would receive utilize an internal clock to receive coordinate data from GPS constellation system  112  once every pre-determined time period (e.g., once every 5 minutes). In one embodiment, however, GPS receiver  212  resets its internal clock to receive coordinate data from system  112  every time step  822  is performed.  
         [0094]     Having explained process  800 , steps  816  and  818  (and consequently steps  810  and  812 , respectively) are now explained in more detail.  
         [0095]     In step  816 , DSP processor  728  first closes switch  716 . Next, DSP processor  728  moves switch  718  to either the FM or AM positions according to the station selected in step  814  from the list of previously identified stations stored in the memory of microprocessor  730 . Taking the example of where the 95.5 FM station is selected in step  814 , DSP processor  728  would set and lock the PLL of FM synthesizer  712  to the frequency of 95.5 MHz, and this generates the “carrier frequency” signal. Then, DSP processor  728  would send a pre-selected, (binary) code signal having a particular frequency to the code modulator  714 . This is the “modulation frequency” signal. The code modulator  714  then injects the coded modulation frequency signal into the carrier frequency signal and sends the resulting test signal to radio  204  via directional coupler  702 .  
         [0096]     In step  818 , the signal received from the speaker output of radio  204  is received through BPF  722 . After filtering the signal for noise, the signal is forwarded to code correlator  726 . Code correlator  726  then determines if the received signal contains the same, within a certain (e.g., &gt;90%) threshold to account for noise, coded modulation frequency signal injected into the carrier frequency signal. If not, this indicates that radio  204  is not tuned to the carrier frequency (i.e., 95.5 FM) of the station under test. If so, this indicates that radio  204  is in fact tuned to the carrier frequency (i.e., 95.5 FM) under test and thus, the coded modulation frequency signal passed through radio  204  and is recoverable by correlator  726 .  
         [0097]     As will be appreciated by one skilled in the relevant art(s) after reading the description herein, the process explained above is similar for an AM station being tested with switch  718  in the AM position and AM synthesizer  708  and AM code modulator  710  performing the respective functions described above.  
         [0098]     As will also be appreciated by one skilled in the relevant art(s) after reading the description herein, step  818  in an embodiment would make use of a variable gain amplifier within SDU  210  in order to perform analog gain control to account for volume differentials within radio  204 .  
         [0099]     In an embodiment of the present invention, the modulation frequency is chosen to be as high as possible so that the vehicle&#39;s occupants cannot hear it (i.e., a frequency inaudible to humans) and that process  800  takes the shortest amount of time to perform. In one embodiment, for example, the modulation frequency is chosen to be 8 kHz when switch  718  is in the FM position and 2 kHz when switch  718  is in the AM position. Further, in an embodiment, when the PLL of FM synthesizer  712  is set to the carrier frequency being tested, the AM synthesizer  708  is set to a carrier frequency that allows it to not interfere in the injection and detection process of steps  816 - 818 , and vice-versa.  
         [0100]     VI. Example Implementations  
         [0101]     The present invention (i.e., VRLS system  100 , vehicle-mounted field unit  108 , server  106 , apparatus  700 , process  800 , and/or any part(s) or function(s) thereof) may be implemented using hardware, software or a combination thereof and may be implemented in one or more computer systems or other processing systems. In fact, in one embodiment, the invention is directed toward one or more computer systems capable of carrying out the functionality described herein. An example of a computer system  600  is shown in  FIG. 6 . The computer system  600  includes one or more processors, such as processor  604 . The processor  604  is connected to a communication infrastructure  606  (e.g., a communications bus, cross-over bar, or network). Various software embodiments are described in terms of this exemplary computer system. After reading this description, it will become apparent to a person skilled in the relevant art(s) how to implement the invention using other computer systems and/or computer architectures.  
         [0102]     Computer system  600  can include a display interface  605  that forwards graphics, text, and other data from the communication infrastructure  602  (or from a frame buffer not shown) for display on the display unit  630 .  
         [0103]     Computer system  600  also includes a main memory  608 , preferably random access memory (RAM), and may also include a secondary memory  610 . The secondary memory  610  may include, for example, a hard disk drive  612  and/or a removable storage drive  614 , representing a floppy disk drive, a magnetic tape drive, an optical disk drive, etc. The removable storage drive  614  reads from and/or writes to a removable storage unit  618  in a well known manner. Removable storage unit  618 , represents a floppy disk, magnetic tape, optical disk, etc. which is read by and written to by removable storage drive  614 . As will be appreciated, the removable storage unit  618  includes a computer usable storage medium having stored therein computer software and/or data.  
         [0104]     In alternative embodiments, secondary memory  610  may include other similar means for allowing computer programs or other instructions to be loaded into computer system  600 . Such means may include, for example, a removable storage unit  622  and an interface  620 . Examples of such may include a program cartridge and cartridge interface (such as that found in video game devices), a removable memory chip (such as an EPROM, or PROM) and associated socket, and other removable storage units  622  and interfaces  620  which allow software and data to be transferred from the removable storage unit  622  to computer system  600 .  
         [0105]     Computer system  600  may also include a communications interface  624 . Communications interface  624  allows software and data to be transferred between computer system  600  and external devices. Examples of communications interface  624  may include a modem, a network interface (such as an Ethernet card), a communications port, a PCMCIA slot and card, etc. Software and data transferred via communications interface  624  are in the form of signals  628  which may be electronic, electromagnetic, optical or other signals capable of being received by communications interface  624 . These signals  628  are provided to communications interface  624  via a communications path (i.e., channel)  626 . This channel  626  carries signals  628  and may be implemented using wire or cable, fiber optics, a phone line, a cellular phone link, an RF link and other communications channels.  
         [0106]     In this document, the terms “computer program medium” and “computer usable medium” are used to generally refer to media such as removable storage drive  614 , a hard disk installed in hard disk drive  612 , and signals  628 . These computer program products are means for providing software to computer system  600 . The invention is directed to such computer program products.  
         [0107]     Computer programs (also called computer control logic) are stored in main memory  608  and/or secondary memory  610 . Computer programs may also be received via communications interface  624 . Such computer programs, when executed, enable the computer system  600  to perform the features of the present invention as discussed herein. In particular, the computer programs, when executed, enable the processor  604  to perform the features of the present invention. Accordingly, such computer programs represent controllers of the computer system  600 .  
         [0108]     In an embodiment where the invention is implemented using software, the software may be stored in a computer program product and loaded into computer system  600  using removable storage drive  614 , hard drive  612  or communications interface  624 . The control logic (software), when executed by the processor  604 , causes the processor  604  to perform the functions of the invention as described herein.  
         [0109]     In another embodiment, the invention is implemented primarily in hardware using, for example, hardware components such as application specific integrated circuits (ASICs). Implementation of the hardware state machine so as to perform the functions described herein will be apparent to persons skilled in the relevant art(s).  
         [0110]     In yet another embodiment, the invention is implemented using a combination of both hardware and software.  
       VII. CONCLUSION  
       [0111]     While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example, and not limitation. It will be apparent to persons skilled in the relevant art(s) that various changes in form and detail can be made therein without departing from the spirit and scope of the invention. For example, the station detection apparatus (i.e., SDU  210 ) and method (i.e., process  800 ) described herein may be used for radios other than those located within vehicles. In fact, after reading this description herein, it will become apparent to a person skilled in the relevant art(s) how to implement the apparatus and method of the present invention for detecting the tuned station of any device having a tuner and a speaker (e.g., television, etc.). Thus, the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.