Abstract:
A radar gun certification system providing for the certification of doppler radar guns and associated tuning forks is described. The certification system incorporates a handheld testing device for use with a mobile computer to certify the devices. The mobile computer interfaces with a server computer which performs the test and stores the test result data. The certification system provides for the certification of radar gun devices in the patrol car by law enforcement agency personnel.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This non-provisional application claims priority of U.S. Provisional Patent Application No. 61/088,218 filed on Aug. 12, 2008, which application is incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    A Doppler radar gun certification system is described which provides for the testing and certification of radar guns and the associated tuning forks. The radar guns and tuning forks used by law enforcement agencies to enforce traffic laws must be periodically tested to certify that they detect speeds and generate frequencies within a tolerance defined by the National Institute of Standards and Technology. Existing technologies for certifying radar guns require highly trained personnel to perform the test, and may require that the radar gun be removed from the patrol car and shipped to a testing facility. 
         [0003]    The improved system may be used by law enforcement personnel with a minimum of training, and provides for testing and certification of the radar gun without removing it from the patrol car. The improved system for certifying such radar guns and tuning forks described herein includes a handheld testing device that interfaces with a mobile computer and a server computer via a network to perform the radar gun and tuning fork certification functions, and to store certification and testing data on the server computer. The handheld testing device and mobile computer may be used to test the radar gun in a vehicle or other location without removing the radar gun from service or sending it to a testing facility. 
       SUMMARY OF THE INVENTION 
       [0004]    The radar gun certification system provides a portable handheld testing device that interfaces with software executing on a mobile computer and a server computer via a network to perform radar gun testing and certification. The handheld testing device includes a speaker for stimulating the radar gun, and a microphone for recording the audio frequency generated by the tuning fork. The handheld testing device is connected to a mobile computer which in turn is connected to a server computer over a network such as the internet. The system may be used to certify a radar gun and also to certify tuning forks used in some radar gun tests. 
         [0005]    When certifying a radar gun, a user of the system interacts with the server computer via software on the mobile computer, triggering the server computer to send a list of appropriate frequencies to the mobile computer which generates and plays the audio signals for those frequencies through a speaker in the handheld testing device, thus testing the radar gun response to specific frequencies. The responses registered by the radar gun are input by the user through the mobile computer, and stored on the server computer. At the completion of testing, the server computer determines if the radar gun has passed the test and if a certification is appropriate. 
         [0006]    When the system is used to certify a tuning fork a user of the system uses the microphone in the handheld testing device to record the sound produced by the tuning fork to an audio file on the mobile computer. The mobile computer then transmits the audio file to the server computer for analysis. The server computer determines the frequencies of the sound in the audio file and compares those frequencies to those appropriate to the specific tuning fork. The results of the test are stored on the server computer and transmitted to the mobile computer. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  is a schematic view of the radar gun certification system. 
           [0008]      FIG. 2  is a diagram of a method of using the radar gun certification system. 
           [0009]      FIG. 3  is a front view of an embodiment of the handheld testing device. 
           [0010]      FIG. 4  is a rear view of an embodiment of the handheld testing device with the rear cover removed. 
       
    
    
     DETAILED DESCRIPTION 
       [0011]    Referring to  FIG. 1 , the certification system  100  is shown in a schematic view. The certification system  100  includes a testing device  102  for stimulating the radar gun using sound waves and for certifying tuning forks by recording the sound waves of the tuning fork. The methods of using the testing device  102  as part of the certification system  100  are described in detail in reference to a later figure. The testing device  102  includes a microphone  104 , a USB sound adapter  105 , a speaker  106 , and a data connector  108 . Although in a preferred embodiment the microphone  104 , the USB sound adapter  105 , and the speaker  106  are contained in a single physical housing, in other embodiments of the certification system  100 , they may be complete separate or attached only via data connector  108 . 
         [0012]    Data connector  108  contains at least one electrical conductor, and in a preferred embodiment of the certification system  100  the data connector  108  is a standard USB cable. The data connector  108 , in a preferred embodiment is of sufficient length to allow the mobile computer to be located in the front of a patrol car while the handheld testing device is used to test a radar gun antenna located in the back of the patrol car. The microphone  104  and the speaker  106  are each connected to the USB sound adapter  105 , which is then connected to the data connector  108 . The data connector  108  connects the testing device  102  to a computer  110  using standard connectors and protocols. In a preferred embodiment of the system  100 , the data connector  108  connects to a USB port on the computer  110 . The data connector  108  may also connect to other types of input/output ports such as wireless data connections including Bluetooth or other wireless technologies. 
         [0013]    The mobile computer  110  may be a general or special purpose computer, but in a preferred embodiment the computer  110  is a general purpose computer running a general purpose operating system, including, but not limited to, Macintosh, Linux, and Windows operating systems, and may be a portable handheld device, a mobile or laptop computer, or a typical desktop computer. In the preferred embodiment of the invention the general purpose operating system is Windows XP/Vista. The computer  110  may also be a cellphone, personal digital assistant or other handheld electronic device. Computer software  112  executes on computer  110 , and may include, but is not limited to, a web browser. In a preferred embodiment of the system  100 , the software  112  is provided by a download via a web browser. Software  112  is installed on computer  110  prior to use for testing a radar gun or tuning fork. 
         [0014]    The computer  110  and software  112  communicate with a server computer  114 . The server computer  114  may be a general or specific purpose computer, and in a preferred embodiment of the system  100  the server computer  114  is a general purpose computer running a general purpose operating system such as Linux, Macintosh or Windows. The server computer  114  may be located remotely from the computer  110 . Server software  116  executes on the server computer  114 , and includes web server software and file transfer protocol (ftp) server software, among others. The web server and ftp server software may be replaced with other technologies that provide similar functionality for remote procedure calls and file transfer. Server software  116  also includes software to analyze sound files received from the mobile computer  110  using the Fourier Transform algorithm. 
         [0015]    The server computer  114  may also transmit executable code or scripts to computer  110 , which, in a preferred embodiment, are executed locally on the computer  110  by the web browser or a plug-in or extension thereof. Such downloaded componets are included as part of software  112 . 
         [0016]    Communication between the computer  110  and the server computer  114  occurs over a computer network  118 . The network  118  may be any data communications network for interconnecting computer systems. In a preferred embodiment of the system  100 , the network  118  is a wide area network such as the internet. 
         [0017]    The server software  116  sends and receives data to and from computer  110 , and also retrieves and stores data in database  120 . The types of data collected are discussed in more detail during the detailed descriptions of the methods of use of the system  100 . Certain portions of the data sent by server computer  116  to computer  110  are in the form of HTML documents, and may include images, text, scripts, and other embedded documents and executable programs of various kinds used and known in the software industry. The server software  116  also sends data that contains information about frequencies and miles per hour (MPH) for specific radar gunds and band to the mobile computer  110 . The audio signals are then generated on the mobile computer  110 , as described below, to stimulate the radar device for purposes of testing it, and received for processing to certify a tuning fork for use. 
         [0018]    The database  120  also stores a mapping of known frequencies to values of miles per hour. The frequency mappings indicate the correct reading of miles per hour that should be registered by a radar gun system when a certain frequency is received by the gun. For example, a radar gun operating on the Ka band should register a reading of 25 miles per hour when it detects a nominal frequency of 2,587.17 Hertz. The mapping data stored in the database  120  is available from the National Institute of Standards and Technology. 
         [0019]    The computer  110  accepts data from a user of the system  100  by means of a user interface. In a preferred embodiment the user interface is a web page displayed in a web browser on computer  110 . The user interface may also be a computer program coded specifically for the purpose of interfacing with the user for purposes of the system  100 . The computer  110  also accepts data from the testing device  102 . The various types of data accepted from the user and the testing device are sent by the software  112  to the server computer  114  for processing by the server software  116 . The server software  116  accepts the data from software  112  and may store it in the database  120 , retrieve other related data from database  120  to return to computer  110 , and compare the received data to previously stored data to determine security authorization and to perform certification testing of radar guns and tuning forks. 
         [0020]    Referring now to  FIG. 2 , a method of using the system  100  to test and certify radar gun systems and tuning forks is described. A law enforcement agency that wishes to use the certification system  100  accesses it through a wide area network, such as the internet, from computer  110  or some other similar computer. In registration  202 , the agency accesses the server computer  114  and portions of server software  116  to register its information in the system  100 . The information provided as part of registration  202  includes, but is not limited to, the name of the agency, contact and billing information for the agency, and the names and security credentials for users authorized to access the system on behalf of the agency. During registration  202 , the agency may proceed to register all radar guns and tuning forks as described below in device registration  208 . The information provided by the agency during the registration process is stored in database  120 . 
         [0021]    After an agency is registered with the system  100  in registration  202 , users authorized by the agency may log into the system  100  via login  204 . Login  204  provides both authorization to a user and also verifies the identity of the user. The login  204  verifies the identity of the user by means of a password, but may also use biometric or other identification means known to the industry to verify the users identity. The user may also provide or update profile information about herself, such as name and preference information. 
         [0022]    Once a user is logged into the system  100 , a radar gun or tuning fork may be selected for testing, or a new device registered with the system to be tested. Device registration  208  allows the user to input data regarding the device. In a preferred embodiment of the system  100 , the device data is input into a web browser form provided by server software  116  to a web browser running on computer  110 . The data input by the user for a radar gun device includes, but is not limited to, the serial number of the radar gun and the frequency band to be tested. The data input for a tuning fork includes, but is not limited to, the serial number of the tuning fork and the frequency identifier information engraved on the tuning fork. 
         [0023]    The data input by the user as part of device registration  208  is transmitted by software  112  to server software  116 . This may be by means of an HTML POST or GET transaction, invocation by the software  112  of a web service on the server computer  114  or by other methods of interprocess communication known in the field of computer science. 
         [0024]    After the device to be tested has been registered with the system  100 , it may be tested according to the appropriate method depending on the type of device, radar gun or tuning fork. The user indicates through selection  210  to the system which type of device will be tested, and based on that selection the software  116  provides the appropriate inputs and functions to the user. 
       Radar Gun Certification 
       [0025]    Referring still to  FIG. 2 , when the user selects the radar gun test in step  210  the software  112  prompts for and accepts the radar gun serial number and the frequency band of the gun from the user in step  212 . In a preferred embodiment of the system  100 , the serial number and other radar gun information is manually entered into the software  112 . In other embodiments it is possible to use radio frequency id tags or similar technology to automatically transfer the radar gun information from the gun to the software  112 . 
         [0026]    The server software stores in database  120  all test results for each radar gun along with additional information such as the user performing the test, the date of the test, and result of each frequency test. In step  214 , the user then positions testing device  102  in relation to the radar gun so that the speaker  106  will cause the gun to register a reading in miles per hour, and then initiates the test through the user interface on computer  110 . 
         [0027]    Once the test is initiated by the user, the server software  116 , in step  218 , generates a list of audio frequencies based on the frequency band of the radar gun and transmits them via the network  118  to computer  110 . In step  220 , computer  110  then generates audio signals at the indicated frequencies and transmits them to the handheld testing device  102  which then plays the audio frequency signals through the speaker  106 . The resulting sound stimulates the radar gun to register a reading in miles per hour, which, in step  222 , is read by the user and input through software  112  and communicated to server software  116 , by similar means to that described above. Server software  116  then stores the radar gun reading in database  120  and computer  110  repeats the process for an incremented audio frequency  224  until readings have been received for all audio frequency signals for the frequency band of the radar gun listed by server software  116  in step  218 . 
         [0028]    After the radar gun readings have been recorded for each desired audio frequency signal, the results input by the user are compared to the correct readings that the radar gun should have registered. If the radar gun readings are within an acceptable margin of error then the radar gun has passed the test and is certified for continued use. The success or failure of the test is presented to the user via data sent from server software  116  to computer  110  in step  226 . 
         [0029]    The system stores the data in database  120 , and the user may access the data later from computer  110  or another similar computer and print a certification report  226  setting forth the results of the test. A user of the system may also access historical test results from database  120  through server software  116  for a specific radar gun, and may compare the test results for a given radar gun over time. 
       Tuning Fork Certification 
       [0030]    If the user selects the tuning fork certification in selection  210 , the computer software  112  prompts the user for the serial number and engraved frequency of the tuning fork through the user interface in step  228 . The user then positions in step  230  the testing device  102  in relation to the tuning fork so that the sound generated by the tuning fork will be recorded by the microphone  104  in the testing device  102 . The user then initiates the recording process  232  through the user interface on computer  110  and taps the tuning fork  234 . In a preferred embodiment, the microphone  104  provides an analog electrical audio signal to the USB sound adapter  105  which then converts it to a digital signal and transmits it to computer  110 , which is then transmitted in step  236  to the server computer  114  through the ftp software included in server software  116 , or some similarly functioning file transmission technology. Alternatively, the testing device  102  may produce a digital representation of the audio signal and provide the digital representation to the server computer  114 . 
         [0031]    In step  238 , server computer  114  receives the digital representation of the audio signal generated from the tuning fork. Server software  116  includes components that are capable of analyzing the digital representation of the audio signal to determine the frequency of the signal contained therein. In a preferred embodiment of the system the frequency analysis component is implements a Fourier Transform algorithm to analyze the frequence of a the digital representation of the audio signal. 
         [0032]    The frequency analysis component of the server software determines the recorded frequency of the tuning fork signal and stores it in database  120 . The server software  116  also compares the recorded frequency of the tuning fork to the nominal frequency of the tuning fork as engraved on it. If the recorded frequency is within allowed tolerances of the nominal frequency the tuning fork is certified for use, and in either case, the result is returned by the server computer  114  to the software  112  in step  226 . 
         [0033]    After completing either type of test, a user may print a report listing the results of the test in step  226  through the software  112  provided on computer  110 . 
         [0034]    Referring now to  FIG. 3 , a front view of an embodiment of the handheld testing device  102  is shown. The device  102  case encloses microphone  104 , speaker  106  and USB sound adapter  105 . 
         [0035]    Referring now to  FIG. 4 , a back view of an embodiment of the handheld testing device  102  is shown with the back cover removed. Microphone  104  and speaker  106  are attached to USB sound adapter  105  via electrical conductors  402  and  404 . The USB connector portion of adapter  105  extends through the case  400  of device  102  for connection to data connector  108 .