Abstract:
A communication system for a vehicle traveling over a road surface is provided with at least one detector for sensing speed detection signals impinging on the vehicle, to monitor the speed of the vehicle or a nearby vehicle. A radiofrequency transmitter communicates the detector output to a receiver adjacent the passenger compartment of the vehicle. The receiver controls one or more annunciators to output one or more annunciator indications to the system user. The radiofrequency transmitter in one embodiment directs transmissions along a ground skip path, reflecting information over the road surface so as to enter the receiver located in or near a passenger compartment of the vehicle. A wireless control unit provides indication of system operating status and allows a user to input commands to the system.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application claims the benefit of U.S. Provisional Application Ser. No. 60/589,192 filed Jul. 19, 2004 which is incorporated by reference herein in its entirety. 

   FIELD OF THE INVENTION 
   The present invention pertains to communication systems for use with moving vehicles and in particular to moving vehicles undergoing speed detection utilizing an external probing signal. 
   DESCRIPTION OF THE RELATED ART 
   With increasing miniaturization of electronics, vehicles are being provided with an ever widening array of information systems. Mapping and position detecting systems, for example, provide the motorist with important data which must be continuously updated. Detection systems have long been popular with motorists to provide an electronic early-warning of nearby speed detection units. Such systems provide either proximity sensing for surrounding speed detection activity or detection of probing signals directed to the motorist&#39;s vehicle. Today, speed detection systems monitor traffic from both radar emitting and laser emitting probing systems of the type used by various law-enforcement agencies to sense and gauge the speed of passing motor vehicles. Traditionally, the range of the typical radar-sensing device exceeds that of most probing devices, thus providing an early warning to motorists of the presence of probing activities. Typically, the warning is early enough to provide a motorist ample time to monitor and adjust vehicle speed, if necessary, before entering the effective operating range of a probing site. 
   In typical speed detection systems, an antenna and receiver is mounted at the front most portion of the vehicle, the location most likely targeted by probing signals. Electronic processing of the signals is required before being presented to the motorist at a location within the passenger compartment adjacent the driver&#39;s position. Electronic circuitry for processing the received signals and providing the motorist with an indication of various aspects of speed detecting activity can be located at the front end of the vehicle, in the engine compartment or in the passenger compartment. It has been necessary to run wiring from the antenna/receiver to the various components and ultimately to a destination adjacent the driver&#39;s position. Routing of wiring is costly, especially so if great care is taken to avoid cluttering the appearance of the motor vehicle. Appearance problems are aggravated in ever increasing ways by the growing number of aftermarket onboard vehicular electronic systems being offered today. As wiring is secreted deeper and deeper within the vehicle so as to remain out of sight, there is a possibility that pinch points and other types of wiring-degrading situations will be encountered, compromising the functional integrity of the installed system. Accordingly, labor and other installation costs for speed detection and other onboard systems which must communicate throughout the length of the vehicle is becoming increasingly costly, even to the point of approaching or perhaps exceeding the cost of the system electronics and hardware. 
   SUMMARY OF THE INVENTION 
   It is an object of the present invention to provide communication systems which extend throughout substantial portions of a vehicle&#39;s length. More specifically, it is an object of the present invention to provide communication systems which extend from the front end of the vehicle, through the engine compartment and firewall to the passenger compartment, to a location in or under the dash adjacent the driver&#39;s seat. 
   Further, it has been found important in providing improved detection of speed sensing activity, that antennas and signal receivers be located at both the front end and rear end of the vehicle. Accordingly, communication signals for the systems must travel throughout the length of the vehicle, being presented to the motorist adjacent the driver&#39;s seat. While the placement of special wiring to the rear end of a front engine vehicle may be somewhat less complicated than wiring extended through the engine compartment, great care must still be taken if unsightly alteration of the vehicle is to be avoided. Accordingly, another object of the present invention is to provide communications systems extending from either the front or the rear end of the vehicle without requiring dedicated additional wiring. More particularly, it is an object of the present invention to provide wireless communications systems or to adapt existing wiring runs extending from the front end and/or rear end of the vehicle to a position adjacent the driver&#39;s seat. 
   In one embodiment of a communication system is provided for a vehicle traveling over a road surface and having a front end, a forward compartment, a passenger compartment, a wall dividing the forward compartment and the passenger compartment, and a rear end. A detector is provided at the front end for sensing speed detection signals impinging on said vehicle, to monitor the speed of said vehicle or a nearby vehicle and to generate an output signal in response thereto. A radio frequency transmitter is provided adjacent the front end for receiving said detector output signal and for transmitting a transmit signal indicative of said speed detection signals in response thereto directed toward said road surface so as to be deflected toward the passenger compartment. A receiver is provided adjacent said wall, either in said front compartment or in said passenger compartment, for receiving said transmit signal from the road surface and for outputting an annunciator signal in response thereto. An annunciator is provided in the passenger compartment, coupled to said receiver to receive said annunciator signal and for outputting an annunciator indication in response thereto. 
   In another embodiment, a communication system is provided for a vehicle traveling over a road surface and having a front end, a forward compartment, a passenger compartment, a wall dividing the forward compartment and the passenger compartment, and a rear end. A detector is provided at the front end for sensing speed detection signals impinging on said vehicle, to monitor the speed of said vehicle or a nearby vehicle and to generate an output signal in response thereto. A radio frequency transmitter is provided adjacent the front end for receiving said detector output signal and for transmitting a transmit signal indicative of said speed detection signals in response thereto. A receiver is provided adjacent said wall, either in said front compartment or in said passenger compartment, for receiving said transmit signal and for outputting an annunciator signal in response thereto. An annunciator is provided in said passenger compartment, coupled to said receiver to receive said annunciator signal and for outputting an annunciator indication in response thereto. 
   In a further embodiment, a communication system is provided for a vehicle traveling over a road surface and having a front end, a forward compartment, a passenger compartment, a wall dividing the forward compartment and the passenger compartment, a rear end and wiring from the front and rear ends to the passenger compartment carrying signals unrelated to monitoring of the speed of the vehicle. A detector is provided at the front end for sensing speed detection signals impinging on said vehicle, to monitor the speed of said vehicle or a nearby vehicle and to generate an output signal in response thereto. A radio frequency injector is provided adjacent the front end for receiving said detector output signal and for injecting a transmit signal indicative of said speed detection signals in response thereto on said wiring for delivery to said passenger compartment. A receiver is operatively associated with said wiring for receiving said transmit signal and for outputting an annunciator signal in response thereto. An annunciator is provided in said passenger compartment, coupled to said receiver to receive said annunciator signal and for outputting an annunciator indication in response thereto. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawings: 
       FIG. 1  is a perspective view of a vehicle incorporating a communications system according to principles of the present invention; 
       FIG. 2  is a perspective view similar to  FIG. 1 , but where communication paths are contained within a vehicle body; 
       FIG. 3  is a cross-sectional view taking along the line  3 - 3  of  FIG. 1 ; 
       FIG. 4  shows the front portion of  FIG. 3 , taken on an enlarged scale; 
       FIG. 5  is a perspective view of a vehicle having an alternative communications system according to principles of the present invention; 
       FIG. 6  is a fragmentary cross-sectional view of a vehicle having an alternative communications system according to principles of the present invention; 
       FIG. 7  is a schematic block diagram of the remote unit portion of the communications system; 
       FIGS. 8   a  and  8   b  together comprise a schematic block diagram of the control unit portion of the communications system; 
       FIGS. 9   a - 9   c  together comprise an electrical schematic diagram of the control unit of  FIG. 7 ; 
       FIGS. 10   a - 10   c  together comprise an electrical schematic diagram of the control unit of  FIGS. 8   a  and  8   b;    
       FIGS. 11   a - 11   c  together comprise an electrical schematic diagram of the voice input portion of the control unit of  FIG. 10 ; 
       FIGS. 12   a - 12   d  together comprise an electrical schematic diagram of the voice output portion of the control unit of  FIG. 10 ; 
       FIG. 13  is an electrical schematic diagram of a programming interface between the remote and controlled units; 
       FIG. 14  is a perspective view of the remote unit from one end thereof; 
       FIG. 15  is a perspective view of the remote unit from an opposite end thereof shown with the communication module omitted; 
       FIG. 16  is a schematic flow diagram of a host Bluetooth start-up and initialization routine; 
       FIGS. 17A-17B  together comprise a schematic flow diagram of a host Bluetooth wireless communications link routine; 
       FIGS. 19A-19B  together comprise a schematic flow diagram of a remote Bluetooth wireless communication line routine; 
       FIG. 19  is a schematic flow diagram of a remote Bluetooth wireless communication line routine; 
       FIG. 20   a - 20   c  together comprise a schematic flow diagram of a start-up main processing loop routine; 
       FIG. 21  is a schematic flow diagram of a host PIC initialization routine; 
       FIGS. 22   aa, ab, ba, bb  together comprise a schematic flow diagram of an incoming voice command processing routine; 
       FIG. 23  is a schematic flow diagram a front remote alert routine; 
       FIG. 24  is a schematic flow diagram of rear remote alert routine; 
       FIGS. 25   a - 25   e  together comprise a schematic flow diagram of a general system timing routine; 
       FIG. 26  is a schematic flow diagram of a remote data receiving routine; 
       FIGS. 27   aa - ad, ba, bb  and  ca - cd  together comprise a schematic flow diagram of a remote data processing routing; 
       FIGS. 28   a - 28   b  together comprise a schematic flow diagram of remote PIC radar polling and processing routine; 
       FIG. 29  is a schematic flow diagram of a remote PIC laser polling and processing routine; 
       FIG. 30  is a schematic flow diagram of a remote PIC initialization routine; 
       FIGS. 31   a - 31   c  together comprise a schematic flow diagram of PIC interrupt service routines for low power and normal operation modes; 
       FIG. 32  is an exploded perspective view of the wireless control unit; 
       FIGS. 33   a - 33   i  together comprise an electrical schematic diagram of the wireless control unit; 
       FIG. 34  is a first sequence diagram illustrating operation of the wireless control unit; and 
       FIG. 35  is a second sequence diagram illustrating operation of the wireless control unit. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   As will be seen herein, the present invention is concerned with providing an early warning to a motorist of various surveillance and probing signals directed to the user&#39;s vehicle. While such detection systems can be quite simple, the more desirable systems sense a variety of different types of probing signals coming from different directions. The present invention is particularly directed to warning systems which are built into the vehicle in a manner so as to be inconspicious as possible. The present invention is concerned with eliminating additional wiring as may be required for a detecting system. As will be seen herein, the present invention contemplates wireless communication to throughout the vehicle and alternatively, adapting existing wiring not intended for use with detecting systems, which is nonetheless provided by the vehicle manufacturer. Accordingly, the communications systems according to principles of the present invention can be embodied in a variety of forms. 
   Referring now to the drawings and initially to  FIGS. 1-4 , a motor vehicle  10  has a front end  12  and a rear end  14 . As is customary, the vehicle  10  is provided with bumpers at the front end and rear end and a license plate frame assembly  16  mounted to the front bumper is visible in the figures. Law enforcement officers and other people engaged in surveillance activities are typically taught to target the license plate when probing the vehicle. In the preferred embodiment, the license plate assembly  16  includes a laser detector and defuser module commercially available from the assignee of the present invention. In the preferred embodiment, a detector  18  for radar radiation is also provided and is located in a forward part of the vehicle, usually separate from the laser detector  16 . An additional detector is optionally installed at the rear of the vehicle. 
   Referring to  FIGS. 14 and 15 , the radar detector  18  comprises a portion of a remote unit generally indicated at  20 . In  FIG. 14 , the front face  21  of the radar detector  18  contains a radar receiving antenna, not visible in the figure. At the opposed end of remote unit  20  an interface or communication block  22  transmits radar detection signals to a control unit in or near the passenger compartment or cockpit. Referring to  FIG. 15 , (which does not show block  22 ) a connector  24  provides local power to the radar detector  18 . One feature of the present invention is that the communication block  22  is retrofitted to existing radar detector units  18 , without requiring modification to the radar detector unit. 
   As mentioned, the license plate assembly  16  is typically chosen as a target for laser probing of the vehicle. The license plate is also typically chosen as a target point for radar probing signals although the radiation beam of the radar probing signals is typically much wider than that for laser probing signals. Also, the radar signals directed to adjacent vehicles and reflections from nearby objects may be sensed by the radar detector in vehicle  10 , thus providing useful information to the driver, in addition to radar probing signals directed specifically at vehicle  10 . 
   Referring to  FIG. 4 , laser probing signals typically have a much smaller beam limited generally to the area of the license plate  32 . Frame work  34  surrounding the license plate contains active circuitry that responds to laser radiation and which emits a laser detecting signal carried on cable  26 , which is received on remote unit  20 . In  FIGS. 1-5 , laser and radar detection signals are wirelessly transmitted to a receiver or control unit  36  located either outside the firewall  38  ( FIG. 2 ) or behind firewall  38  within the passenger compartment  40  (see  FIGS. 1 ,  3  and  5 ). In  FIG. 6 , laser and radar detection signals are impressed on existing power wiring  42  such as that installed by the vehicle manufacturer, and which is not intended for use with a detection system. 
   As shown in  FIGS. 1-3  and  6 , the laser and radar detection signals are passed through a forward compartment  44  of vehicle  10 , located in front of passenger compartment  40 . With reference to  FIG. 1 , vehicle  10  also includes a rear compartment  46  and a second remote unit  20  passes detector signals through rear compartment  46  to control module  36  located in the passenger compartment. The rear remote unit  20  is usually limited to reception of radar signals only. Thus, in the embodiment illustrated in  FIG. 1 , vehicle  10  is said to be provided with forward and rearward looking radar detection capability. The communication system according to principles of the present invention conducts detecting signals from various sources over various paths to the receiver or control unit  36  which advises the driver of surveillance and probing activity, preferably via one or more annunciators. It should be noted that communication systems according to principles of the present invention work equally well for front engine, mid engine and rear engine vehicles. For purposes of explanation herein, it will be assumed that vehicle  10  is a front engine vehicle and that front compartment  44  contains the usual engine components, while compartment  46  at the rear of the vehicle comprises a conventional trunk space. 
   Referring again to  FIGS. 14 and 15 , remote unit  20  includes communication block  22 . Other relative orientations of the radar receiving antenna and radio frequency transmitting antenna are possible. For example, in  FIG. 5  the radio frequency transmitting antenna is transmitted in a sideways direction to bounce off of nearby objects so as to enter the passenger compartment  40  from the side. If desired, a radio receiver  54  can be located at the side of the vehicle for connection to control unit  36  with a relatively short wiring run  56 . Preferably though, the wireless communication path provided by the communication system accordingly to principles of the present invention traverses generally longitudinal paths from the front and rear of the vehicle to the passenger compartment or a firewall located adjacent a front or rear compartment. 
   Referring briefly to  FIGS. 1 and 2 , the wireless communication paths are shown in the engine compartment  44 . As indicated, the communications paths of the radio frequency signals emitted from the remote unit  20  are reflected within the engine compartment, eventually passing to the control unit  36 . In  FIG. 1 , one signal path  58  is reflected from the ground so as to be received at control unit  36 . This ground skip path comprises one of the paths of radiation emitted from remote unit  20  (and subsequently detected in a receiver). In  FIG. 2 , it is assumed that no ground skip signal is present and that radiation of the wireless signal from remote unit  20  to control unit  36  is contained within vehicle  10 . In the arrangement of  FIG. 2 , additional signals otherwise provided by ground skip paths are unavailable for improved detection capability by wireless receivers located in control unit  36 . In  FIG. 2 , control unit  36  is located within the forward compartment  44  and is attached to firewall  38  or another convenient mounting site. In  FIG. 1 , control unit  36  which receives the wireless signals is located behind firewall  38 , and passenger compartment  40 . 
   As will be appreciated by those skilled in the art, the firewalls of conventional vehicles are perforated with passageways for equipment and wiring and radio frequency signals can conveniently travel through these firewall openings (in addition to the ground skip paths, previously mentioned). If signal attenuation at the control unit  36  is excessive, the control unit can be mounted in the forward compartment, as shown in  FIG. 2 , and relatively short wiring can pass through the firewall to visual and audible annunciators located within the passenger compartment. In the preferred embodiment, the radio frequency link between remote unit  20  and control unit  36  operates on a frequency approved for use by the Federal Communications Commission. Preferably, the radio link uses a 2.4 GHz carrier frequency although other carrier frequencies such as possible future frequencies in the unlicensed spectrum in the 450 MHz and 900 MHz bands could be used as well. In the present invention, a cost effective conventional interface is employed to ensure orderly and reliable transmission of data bits between remote units  20  and control unit  36 . It is generally preferred that the Bluetooth radio interface standard is employed, to accommodate optional features such as the wireless control unit to be described herein, and to take advantage of future integration opportunities with other motor vehicle devices. The invention contemplates other popular interfaces such as Wi-Fi, CDMA, TDMA, TDD, FDD and analog, for example. 
   One problem to be dealt with in a practical wireless link is a situation where two radio frequency signals or vectors arrive at the control unit at the same time. For example, one vector could bounce over the ground surface while another vector could bounce from surfaces of the vehicle. The Bluetooth interface standard preferred in the present embodiment has provision for distinguishing one simultaneous vector from another using a predetermined timing assignment. Once a vector is received with sufficient strength to be reliably demodulated, other vectors with the same time stamp are ignored. The ability to have additional vectors traveling along ground skip paths provides a substantial advantage in system operation and reliability. Also, wireless reception in the control unit  36  can be processed such that an incoming signal is considered to be reliable only when multiple vectors carrying that signal are considered to be reliable. In this latter instance, the ability to receive the additional vectors traveling over ground skip paths can provide a substantial operating advantage. 
   Depending upon the path preferences within vehicle  10 , the antenna for transmitting radio frequency information from remote unit  20  can be tailored to prefer one communication path over another to avoid unusually strong attenuation circumstances which may arise due to vehicle construction. With the present invention, different communication blocks can be provided with the radar detector module at the time of installation, to customize the communication system for a particular vehicle. 
   Before proceeding to a more detailed explanation of the wireless embodiments of communications according to principles of the present invention, attention will be directed to  FIG. 6  where existing vehicle wiring is adapted to provide a communication system for detection devices. In  FIG. 6 , a remote unit  20  is connected to internal wiring  42  of the vehicle provided by the vehicle manufacturer, for delivering direct current power, for example. Radio frequency detection signals from the remote unit(s)  20  are impressed on the wiring which typically carries a direct current power signal. The radio frequency data is virtually identical to the radio frequency data in a wireless embodiment. Conventional equipment such as that provided by Cambridge Silicon Radio, Zeero or TI can be employed for this purpose. 
   Referring now to  FIG. 7 , the remote unit  20  will be described in greater detail. Component  60  contains the radio interface protocols. The choice of protocols is independent and Bluetooth is selected for illustration because of its cable replacement use. The electronics component  60  obtains the electrical power necessary to operate by using power circuit  62  of conventional construction. The power circuit  62  is connected to a DC voltage source of 12 volt potential, capable of delivering a minimum current of 100 milliamperes. The connection is made through an external wire cable  65  shown in  FIG. 14  which enters the internal components through communication block  22 . A controller is used to collect the output of the radar module  18  as indicated at  66  in  FIG. 7 . The controller  66  preferably comprises a micro controller, catalog number PIC16F627-04I/SS, available from Microchip Technology located at Chandler, Ariz. Other types of controllers or microprocessors could be employed, as desired. The controller is chosen so as to accommodate the inputs  66  of the radar module and inputs  68  of the laser module. The radar and optionally laser detector signals are analyzed and sent along using one of the radio interfaces and vector paths between remote unit  20  and control unit  36  as indicated in the Figures. The software necessary to run the communication system of remote unit  20  is loaded through an interface using SPI techniques. 
   The control unit  36  uses the circuit depicted in block form in  FIG. 8  (shown divided between  FIGS. 8   a  and  8   b  for clarity). The radar detector data transmitted from remote unit  20  is received at host module  76 , via antenna  77 . The antenna  77  is internal to the body of the control unit and preferably comprises a surface mount component on the printed circuit board of the wireless control unit  36  so as to maintain a clean profile and to allow installation in the largest population of different vehicle configurations. Information received at host module  76  is passed along to a main control unit  78 , a micro controller, catalog number PIC16LF873A-I/SS from Microchip. The main control unit  78  processes received information and alerts the driver of the vehicle  10  by activating an appropriate light emitting diode  80  or  82 . In addition, a voice alert code is sent to an optional voice recognition unit  86 . The voice recognition unit  86 , when employed, preferably comprises a conventional voice recognition integrated circuit commercially available as part number RSC-4128 commercially available from the Sensory Company located at Santa Clara, Calif. The voice recognition unit  86  uses the code given by main control unit  78  to access a preprogrammed sound file and external EEProm  90  so as to play the appropriate message at speaker  92 . In the preferred embodiment, commands are given to the control system  36  by the driver, using vocal directives. Other input techniques known in the art, can also be used. In an optional control unit voice recognition capabilities are provided by voice recognition unit  86 , using microphone  94 . The voice commands delivered to the voice recognition unit  86  by the microphone are processed and matched according to values stored in the external memory unit  90 . If desired, the voice recognition unit can be omitted, for example, in favor of a wireless remote control unit  130  to be described later, herein. 
   More detailed electronic schematic diagrams for the remote and control units are given in  FIGS. 9   a - 9   c ,  10   a - 10   c ,  11   a - 11   d ,  12   a - 12   d  and  13 . For example, module  60  of  FIG. 7  which delivers data to transmitting antenna  61  is indicated in the electrical schematic diagram of  FIGS. 9   a - 9   c  as module U 7  which preferably comprises a Bluetooth radio module, catalog number BC219159DN-E4 available from CSR located in Cambridge, UK. The PIC controller  66  in  FIG. 7  is shown in  FIGS. 9   a - 9   c  is commercially available as part no. PIC 16F627-041/SS from Microchip Technology of Chandler, Ariz. Data outputted from unit U 7  is transmitted via RF link  102  from controller  66 . Output signals are sent by control unit  66  in response to radar data signals on line  104  and laser data signals on line  106  coupled to the radar detector module  18  and laser detector module  16  respectively of  FIG. 1 , for example. Referring now to  FIGS. 9   a - 9   c , a connector  110  (see  FIG. 9   b ) is provided for Bluetooth programming, using the interface circuit  112  shown in  FIG. 13  which couples connector  110  to a connector  114  of  FIGS. 10   a - 10   c.    
   Referring now to the electrical schematic diagram of  FIGS. 10   a - 10   c , connector  114  is coupled to Bluetooth host module U 2 , which is identical to module  76  of  FIGS. 8   a ,  8   b . Bluetooth module U 2  is coupled through UART Universal Asynchronous Receiver/Transmitter coupling  118 . This coupling is in turn terminated at terminals  120  of the PIC main controller  78  also shown in  FIG. 10   c . Output lines  122  from controller  78  energize light emitting diodes  80 ,  82 . Voice commands from optional voice recognition unit  86  in  FIG. 11   c  are received at input lines  126  of controller  78  as shown in  FIG. 10   a . Tones generated by controller  78  are outputted on lines  128  as shown in  FIG. 10   a  so as to be received at input lines  131  in  FIG. 12   a . This tone generator data is processed and sent to speaker  92  in  FIG. 12   d . In the electrical schematic diagrams of  FIGS. 11   a - 11   d  and  12   a - 12   d , the same voice recognition unit  86  preferably comprises a voice processor chip, catalog number RSC-4128 Romless available from Sensory Inc. of Santa Clara. 
   The various control modules and voice recognition units must be programmed to function as described herein. Flowchart diagrams are given for the devices of various portions of the communication system in  FIGS. 16 ;  17   a, b ;  18 ;  19   a, b ;  20   a - c ;  21 ;  22   aa, ab, ba, bb ;  23 - 24 ;  25   a - c ;  26 ;  27   aa - ad, ba, bb,  and  ca - cd ;  28   a, b ;  29 ;  30 ; and  31   a - c.    
     FIG. 16  is a schematic flow diagram of a host Bluetooth start-up and initialization routine. The code for this routine is stored in U 2 , reference number  92 , see  FIG. 12   d.    
     FIGS. 17   a, b  together comprise a schematic flow diagram of a host Bluetooth wireless communications link routine. The code for this routine is stored in U 2 , reference number  92 , see  FIG. 12   d.    
     FIG. 18  is a schematic flow diagram of a remote Bluetooth start-up and initialization routine. The code for this routine is stored in U 7 , reference number  47 , see  FIG. 9   b.    
     FIGS. 19   a, b  together comprise a schematic flow diagram of a remote Bluetooth wireless communication link routine. The code for this routine is stored in U 7 , reference number  47 , see  FIG. 9   b.    
     FIG. 20   a - 20   c  together comprise a schematic flow diagram of start-up main processing loop routine. The code for this routine is stored in U 3 , reference number  78 , see  FIG. 10   a.    
     FIG. 21  is a schematic flow diagram of a host PIC initialization routine. The code for this routine is stored in U 3 , reference number  78 , see  FIG. 10   a.    
     FIG. 22   aa, ab, ba  and  bb  together comprise a schematic flow diagram of an incoming voice command processing routine. The code for this routine is stored in U 10 , reference number  86 , see  FIG. 11   c.    
     FIG. 23  is a schematic flow diagram of a front remote alert routine. The code for this routine is stored in U 3 , reference number  78 , see  FIG. 10   a.    
     FIG. 24  is a schematic flow diagram of rear remote alert routine. The code for this routine is stored in U 3 , reference number  78 , see  FIG. 10   a.    
     FIGS. 25   a - c  together comprise a schematic flow diagram of a general system timing routine. The code for this routine is stored in U 3 , reference number  78 , see  FIG. 10   a.    
     FIG. 26  is a schematic flow diagram of a remote data receiving routine. The code for this routine is stored in U 3 , reference number  78 , see  FIG. 10   a.    
     FIGS. 27   aa, ab, ba, bb,  and  ca - cd  together comprise a schematic flow diagram of a remote data processing routing. The code for this routine is stored in U 3 , reference number  78 , see  FIG. 10   a.    
     FIGS. 28   a, b  together comprise a schematic flow diagram of remote PIC radar polling and processing routine. The code for this routine is stored in U 8 , reference number  64 , see  FIG. 9   c.    
     FIG. 29  is a schematic flow diagram of a remote PIC laser polling and processing routine. The code for this routine is stored in U 8 , reference number  64 , see  FIG. 9   c.    
     FIG. 30  is a schematic flow diagram of a remote PIC initialization routine. The code for this routine is stored in U 8 , reference number  64 , see  FIG. 9   c.    
     FIGS. 31   a - c  together comprise a schematic flow diagram of PIC interrupt service routines for low power and normal operation modes. The code for this routine is stored in U 8 , reference number  64 , see  FIG. 9   c.    
   Referring now to  FIG. 8   a , a wireless control unit  130  is provided to allow a user to wirelessly communicate with the warning system, without requiring extensive modification to the interior of the user&#39;s vehicle. As will be seen herein, the wireless control unit  130  allows a user to input commands to the warning system and to receive status indications of various portions of the system. Preferably, the wireless control unit  130  is Bluetooth enabled, operating as a remote module communicating with the aforementioned Bluetooth system which includes, for example, the Bluetooth host module  76 . 
   Referring now to  FIG. 32 , wireless control unit  130  includes a housing  140 , enclosed at one end by a battery door  142 . Disposed within housing  140  are a plurality of battery contacts  146  and a pair of batteries  148 . Electrical leads  150  connect the batteries to a main printed circuit board  154  which is coupled to a lower, radio frequency (RF) printed circuit board  158  by connectors  160 ,  162  (see  FIG. 33   g ). A graphic overlay member  166  includes a plurality of dome switches  168 . The dome switches make electrical contact with contacts  170  carried on main printed circuit board  154 , in a conventional manner. 
   Referring now to  FIGS. 33   a - 33   i , an electrical schematic diagram for circuitry carried on printed circuit boards  154 ,  158 , is shown. A microprocessor  176  is carried on the lower, RF printed circuit board  154  and has connections coupled to connector  160 . Microprocessor  176  is commercially available as part no. BC219159BN-E4, from CSR located in Cambridge, UK. Microprocessor  176  is connected to an antenna  180  for radio frequency communication with the Bluetooth host module  76  described above. Asynchronous communication with a microprocessor  184  carried on main printed circuit board  154  is made by leads  182  which connect terminals J 10 , J 11  of microprocessor  176  to terminals  8  and  9  of microprocessor  184  via connectors  160 ,  162 . Microprocessor  184  is commercially available as part no. PIC16LF627A-041/SS, from Microchip Technology of Chandler, Ariz. Also associated with microprocessor  176  is a crystal-controlled clock circuit  188  and a connector  190  to provide external control programming for the Bluetooth functions of microprocessor  176 . 
   A Bluetooth enabler circuit  194  is coupled to terminal  7  of microprocessor  184  to enable its Bluetooth operations. Included in circuit  194  is a microprocessor, part no. MAX4795EUK. In effect, circuit  194  functions as an external electronic switch that provides power to the Bluetooth circuit carried on the lower, RF printed circuit board  158 . 
   Referring to  FIG. 33   d , the main printed circuit board  154  is provided with three membrane switches, including a filter switch  200 , a volume switch  202  and a mode switch  204 . These switches are connected to terminals  12 ,  13  and  14  of microprocessor  184  and provide input control signals. Referring now to  FIG. 33   i , the main printed circuit board is also provided with a plurality of indicator lights arranged in a bank or array  206 . The indicator lights preferably comprise light emitting diodes, although virtually any type of indicator can be used whether visual, audible or vibratory. LED  210 , when illuminated, indicates high volume operation of the detection system, while LED&#39;s  212 ,  214  indicate a low volume and a volume off operation of the detector system. Indicator light  216  indicates that power to the detector system has been turned off, confirming to the user that the detector system is not emitting signals which might possibly be detected by outside observers. Indicator lights  218 ,  220  indicate familiar “city” and “highway” operation (i.e. low gain and high gain operation, respectively) of the detector system. Indicator lights  222 ,  224 , are provided for optional functions such as voice control and audible “tones” outputs of the detector system. 
   The detector system of the preferred embodiment uses a wireless control link between wireless control unit  130  and Bluetooth host module  76 . In the preferred embodiment, the wireless protocol is chosen to be a Bluetooth protocol although virtually any wireless protocol can be employed, as desired. The wireless control unit  130  is expected to be operated from within the vehicle passenger compartment to provide control over the detector system and to provide an indication of system status to the user. If desired, the wireless link can be replaced with a wired connection. Programming of microprocessor  60  (see  FIG. 9   a ) and microprocessor  176  (see  FIG. 33   f ) preferably includes an algorithm which provides current state recall, defined herein as the current operational mode of the overall detector system. According to one aspect of the present invention, the detector system employs current state recall which not only allows the wireless control unit  130  to consume very small amounts of power and to have an ultra small size, but which also requires a minimum amount of electronics to implement the overall system. For example, the current state recall operation of the detector system, in the preferred embodiment, requires only two micro controllers (microprocessor  184  of  FIG. 33   h  and microprocessor  64  of  FIG. 9   c ) and two Bluetooth transceivers (microprocessor  60  of  FIG. 9   a  and microprocessor  176  of  FIG. 33   f ). 
   Referring to  FIG. 33   d , upon the pressing any of the switches  200 ,  202 ,  204  the respective terminals of microprocessor  184  connected to the switches detects a voltage rise. In response, code associated with microprocessor  184  closes a circuit or switch internal to the microprocessor that outputs a command signal on terminal  7  which in turn is delivered to terminal  3  of the microprocessor of Bluetooth enabler circuit  194 . The Bluetooth enabler circuit  194  responds by applying power to the Bluetooth circuit associated with microprocessor  176 , enabling the microprocessor of the wireless control unit  130  to receive a status signal from host module  76 , via the wireless Bluetooth link. The microprocessor  184  processes the incoming status signal and determines which of the appropriate indicator lights  210 - 224  should be illuminated to indicate visual status of system operation to the user. For example, concerning the current volume mode of the detector system, only one of the indicator lights  210 ,  212  and  214  should be illuminated at any one time to indicate only one of the three possible volume operating modes (i.e. volume high, volume low, or volume off). If the incoming status signal received from host module  76  by wireless control unit  130  indicates that system volume is turned off, microprocessor  184  would issue a signal to indicator light  214  to illuminate that indicator light. Similarly, only one of the indicator lights  218 ,  220  is expected to be illuminated at a particular time so as indicate to the user that the system is operating in city (low gain) mode or highway (high gain) mode. 
   Referring now to  FIG. 34  a sequence diagram indicating operation of the overall detector system is shown. In step  240 , a key press or “any—key—down” is sensed by microprocessor  184 . In response, the microprocessor sends a power up signal to the Bluetooth circuitry associated with microprocessor  176 . As mentioned, a “Bluetooth enable” signal is sent to external solid-state switch circuit  194 , through which power is applied to the Bluetooth portion of microprocessor  176 . In step  246  the last state of the overall system is sent to the array of indicator lights. Upon powering up, the Bluetooth circuitry attempts to connect to the host module  76 . 
   Upon a successful connection, the host Bluetooth module  76  (see  FIG. 8   a ) syncs the RF link with the wireless remote  130  and confirms the connection using the standard Bluetooth connection protocols outlined in the Bluetooth standard, as indicated in step  248 . At this time, the host module  76  sends a status signal to the Bluetooth module  176 , using system status information stored in the host module memory. The Bluetooth module of the wireless control unit  130  then communicates to the microprocessor  184  that an RF link has been established between the wireless control unit  130  and host module  76 , (as indicated in step  250 ) and passes the status signal information to microprocessor  184 , updating or confirming the present system status to the wireless control unit  130 . If desired, the indicator lights of the wireless control unit can be cleared upon an initial key press, with reception of the status signal from the host module determining the state of the indicator lights, rather than serving as a data update. At this point, a timed interval is initiated. In the preferred embodiment, the time interval has a 5-second duration, although virtually any duration can be employed. During the time interval each key press of the wireless control unit  130  is passed to the host module  76  as indicated at  254 . Only key presses made during the timed interval, i.e. while the Bluetooth connection is active, are passed to the host module  76 . If there is no key press activity during the time interval, the timer of the wireless control unit  130  expires, and microprocessor  184  triggers Bluetooth enable circuit  194  to open, thus breaking the Bluetooth connection with the host module  76 . The microprocessor  184  then returns to a sleep mode drawing only a minimal amount of current from the small power system, preferably the batteries  148 . 
   Referring to  FIG. 35  if Bluetooth connection between host  76  and wireless control unit  130  is not established within 5 seconds, the wireless control unit  130  sends a command to Bluetooth enable circuit  194  to open a Bluetooth transmission link and to enter a sleep mode. 
   As mentioned, the preferred embodiment employs Bluetooth protocols between the wireless control unit  130  and the host module  76 , to allow the host module to communicate with the wireless control unit as if it were another remote sensor of the system. Although less preferable, other, mixed protocols can be employed, if desired, with different protocols used for the remote sensors and for the wireless remote unit  130 . 
   The drawings and the foregoing descriptions are not intended to represent the only forms of the invention in regard to the details of its construction and manner of operation. Changes in form and in the proportion of parts, as well as the substitution of equivalents, are contemplated as circumstances may suggest or render expedient; and although specific terms have been employed, they are intended in a generic and descriptive sense only and not for the purposes of limitation, the scope of the invention being delineated by the following claims.