Abstract:
A fueling environment communication system for providing high bandwidth information via existing field wiring to a plurality of forecourt devices. The communication system according to this aspect comprises a back room communication module having a first plurality of Ethernet ports for connection to external devices using Ethernet communication and a second plurality of Ethernet ports. The back room communication module further comprises a plurality of modulation interface devices each connected on a first side to a respective one of the second plurality of Ethernet ports. A summing and isolation module having a high pass filter is connected to each of the modulation interface devices on a second side thereof to pass a modulated high frequency signal. The summing and isolation module further has a low pass filter through which low frequency legacy data can be passed and combined with said modulated high frequency signal. In addition, summing and isolation module is connectable via existing field wiring to communicate with forecourt devices in point-to-point fashion.

Description:
PRIORITY CLAIM 
     The present application is based upon and claims the benefit of U.S. provisional application Ser. No. 61/560,624, filed Nov. 16, 2011, which is incorporated herein by reference in its entirety for all purposes. 
    
    
     BACKGROUND OF THE INVENTION 
     The invention relates generally to fueling environments in which a plurality of reel dispensers are located in a forecourt area. More particularly, the present invention relates to a fueling environment utilising a retrofit communication system to provide broadband communication over legacy field wiring. 
     Existing fuel service forecourts are typically equipped with field wiring to provide communication between a point-of-sale system (POS) and the individual fuel dispensers for forecourt kiosks). The POS typically includes a forecourt controller function in order to control the operation of the individual fuel dispensers. Also, in the case of “pay at the pump,” the POS receives payment information from the fuel dispensers in order to authorize the transaction and effect final payment. Recently, Gilbarco Inc., the assignee of the present invention, has proposed a system wherein certain forecourt functions are performed by a separate device (referred, to as an “enhanced dispenser hub”) that communicates with a POS. The operation of an enhanced dispenser hub in a fueling environment is described in U.S. Pub. No. 2010/0268612, incorporated fully herein by reference for all purposes. 
     The prior art typically uses two-wire current loop or RS422 signaling for communications between the POS (or other back room controller) and the forecourt devices (e.g., fuel dispensers). These communication systems date to an era when dispensers were first connected via electrical signals and can typically provide no more than about 5 to 20 kbps of data throughput. However, the functionality desired at fuel dispensers has outgrown the limited capability that can be achieved with such low data rates. 
     For example, in recent years, fuel dispensers have become more than a means for fueling a vehicle. Service station owners are advertising at the dispenser with everything from simple signs to video displays running commercials. Some service stations have integrated fast-food or quick-serve restaurants, and the dispensers may allow the customer to order food from these restaurants. Additionally, the POS systems facilitate ordering other services, such as car washes, at the fuel dispenser. Most modern fuel dispensers include card readers or other payment means allowing payment for not only fuel, but also any products or services ordered at the dispenser. 
     These data-intensive features can be readily provided in a new service station because high bandwidth cable can be installed in the forecourt during construction. In the case of existing service stations, the cost to provide high bandwidth cable (e.g., Cat5) in the forecourt can be prohibitive. Alternative technologies, such as wireless solutions, may be prone to interference and outages, in view of these shortcomings, there have been attempts to provide legacy field wiring with high bandwidth capability. Some such devices use a mesh network topology (for example, utilizing power line communications technologies) that limits the total forecourt bandwidth. As a result each device suffers a loss of data throughput as more forecourt devices are added. Existing devices may also further compromise or limit data rates between a central controller and forecourt devices if significant data must be transmitted between forecourt devices and the central controller. 
     One example of a prior art system that attempts to provide a composite signal to a fuel dispenser using legacy wiring is shown in U.S. Pub. App. No. 2009/0129403 A1, incorporated herein by reference for all purposes. 
     SUMMARY OF THE INVENTION 
     The present invention recognizes and addresses the foregoing considerations, and others, of prior art constructions and methods. 
     In accordance with one aspect, the present invention provides a fueling environment communication system for providing high bandwidth communication via existing field wiring to a plurality of forecourt devices. The communication system according to this aspect comprises a back room communication module having a first plurality of Ethernet ports for connection to external devices using Ethernet communication and a second plurality of Ethernet ports. The hack room communication module farther comprises a plurality of modulation interface devices each connected on a first side to a respective one of the second plurality of Ethernet ports. A combiner module having a high pass filter is connected to each of the modulation interface devices on a second side thereof to pass a modulated high frequency signal. The combiner module further has a low pass filter through which low frequency legacy data can be passed and combined with said modulated high frequency signal. In addition, the combiner module is connectable via existing field wiring. 
     In accordance with another aspect, the present invention provides a system for providing high bandwidth communication via two wire field wiring coexisting in a power feed conduit with AC power wiring. The communication system according to this aspect comprises back room circuitry including a communication module having a first plurality of Ethernet ports for connection to external devices using Ethernet communication and a second plurality of Ethernet ports. A plurality of modulation interface devices are each connected on a first side to a respective one of the second plurality of Ethernet ports. Electrical isolation circuitry is connected on one side to respective modulation interface devices and connectable on another side to respective two wire field wiring. The modulation interface devices are operative to modulate and demodulate a modulated high frequency signal to communicate with remote devices in point-to-point fashion. The electrical isolation circuitry provides breakdown isolation of at least 3500 volts. 
     A further aspect of the present invention provides a system for providing high bandwidth communication via two wire field wiring coexisting in a power feed conduit with AC power wiring. The communication system according to this aspect comprises hack room circuitry including a communication module having at least one first Ethernet port for connection to an external device using Ethernet communication and at least one second Ethernet port. A respective modulation interface device is connected on a first side to the at least one second Ethernet port. Electrical isolation circuitry is connected on one side to the modulation interface device and connectable on another side to the two wire field wiring. The modulation interface device is operative to modulate and demodulate a modulated high frequency DSL signal to communicate with a remote device. The electrical isolation circuitry provides breakdown isolation of at least 3500 volts. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A full and enabling disclosure of the present invention, including the best mode thereof directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended drawings, in which; 
         FIG. 1  is a diagram of a fueling environment incorporating a retrofit communication system in accordance with an embodiment of the present invention. 
         FIG. 2  is a detailed diagram of a back room communication module (BRCM) illustrated in  FIG. 1 . 
         FIG. 3  is a detailed diagram of a two-wire buffer module (TBM) illustrated in  FIG. 1 . 
         FIG. 4  is a detailed diagram of a dispenser communication module (DCM) illustrated in  FIG. 1 . 
         FIG. 5  is a diagram showing an alternative embodiment of a DCM in accordance with the present invention. 
     
    
    
     Repeat use of references numbers or characters in the present specification and drawings is intended to represent same or analogous features or elements of the invention. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Reference will now be made in detail to presently preferred embodiments of the invention, one or more examples of which are illustrated in the accompanying drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that modifications and variations can be made in the present invention without departing from the scope or spirit thereof. For instance, features illustrated or described as part of one embodiment may be used on another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations. 
     The present invention provides high quality data connectivity using existing (“legacy”) field wiring without encountering problems of the current art. Various applications are facilitated by the invention, such as streaming of real time high definition video, real time surveillance camera data, decreased transaction time for secure payment transactions (which have considerably higher data requirements than non-secure transactions), and more comprehensive dispensing control (including real time sensing necessary for improved environmental sensing, wet stock management and fuel inventory control). Aspects of the present invention may also be useful with displays on top of fuel dispensers and service station price signs. As explained, aspects of the present invention may also be useful in various non-fuel (e.g., industrial) applications requiring broadband transmission within AC conduit applications. 
     Preferred embodiments of this invention provide greater than 50 Mbps downstream (toward forecourt devices) and greater than 25 Mbps upstream (toward the central controller). As a result, there is sufficient bandwidth such that many applications can be run independently with regard to each device on the forecourt, and work in the presence of existing low bandwidth data (i.e., legacy pump control or payment data) using legacy wiring. In addition, the content to each dispenser can be customised based, for example, on the customer&#39;s loyalty information. 
       FIG. 1  shows an exemplary fueling environment utilising a retrofit communication system  10  in accordance with the present invention. The communication system  10  is employed between an existing POS, or, as shown here at  12 , the combination of a POS and an enhanced dispenser hub (“EDH”). The POS (or POS plus EDH) typically communicates with a distribution box (“D-box”)  14  via two wire current loop protocol or RS422 signaling, depending on the manufacturer. In this case, as shown, such communication occurs by two-wire. As will be explained more fully below, distribution box  14  contains components that combine low frequency data from the POS with high bandwidth data provided by other sources. The combined data is provided via field wiring (collectively  16 ) to the respective fuel dispensers (such as fuel dispenser  18 ) or kiosks that are located in the forecourt area. 
     The field wiring  16  will typically be two-wire current loop wiring that is already installed on the forecourt, although new wiring could also be installed. As will be explained more fully below, distribution box  14  (as well as the BRCM  24 , discussed below) is typically adapted to allow broadband circuit elements to coexist within high voltage AC wiring conduits. As a result, in conjunction with appropriate trace spacing, distribution box  14  (or the BRCM  24 ) can directly interface with permanently installed physical electrical conduits (such as conduit  20 ) that carry AC power to the forecourt devices. In fact, although described in connection with a fueling environment, one skilled in the art will appreciate that a communication system described herein has application in many industrial environments where broadband communications need to coexist with high voltage AC power conduits. 
     As shown, embodiments of the present invention preferably utilise a point-to-point arrangement between the back room components and the forecourt devices. As a result, any number of forecourt devices may be provided without sacrificing bandwidth to each one. Moreover, independent applications may be utilized with the respective forecourt devices. Also, while the field wiring will often be twisted pair, embodiments of the present invention contemplate use of non-twisted pair wiring as well. This can be achieved because of the exceptional bandwidth and signal conditioning provided by aspects of the preferred embodiments. 
     In this embodiment, distribution box  14  includes multiple two-wire buffer modules (“TBM”)  22   a  and  22   b  that provide communication to eight forecourt devices each (for a total of sixteen). In this embodiment, TBM  22   a  communicates with TBM  22   b  via external loop drive (because only one of them is connected to the POS). The TBMs each receive eight high bandwidth inputs from respective back room communication modules (BRCMs)  24   a  and  24   b . In this case, BRCMs  24   a  and  24   b  are mounted within a common chassis  26 . 
     As will be explained more fully below, each BRCM  24   a  and  24   b  includes one or more multiport switches, such as a gigabit Ethernet switch, to interconnect various Ethernet devices to the communication system. In this embodiment, for example, an operator and maintenance module (“OAM”)  28  is connected to BRCM  24   a . The OAM may be configured to allow an operator to perform various maintenance and monitoring functions relative to the communication system. In addition, a media server  30  is provided to present advertisements and other information messages to the fuel dispenser customer. These may include, for example, video messages, coupons, or internet content. A suitable modem provides connection to the communication system via another port of the Ethernet switch. On the other side, the Ethernet switches of each BRCM provide multiple signal ports for the respective forecourt devices. 
     Within the dispensers, communication system  10  includes a dispenser communication module (“DCM”)  32  that interlaces with the dispenser&#39;s legacy systems. Such systems include a pump control node (“PCN”)  34  which includes the hardware and software necessary to control the dispenser hydraulic functions. The GRIND (card reader in dispenser) module  36  includes the hardware and software necessary to support payment processing and peripheral interfaces, such as card reader  38 , PIN pad  40  and graphical display  42 . In this embodiment, communication with PCN  34  occurs by legacy protocol whereas communication with GRIND  36  is via Ethernet. Embodiments are contemplated in which both Ethernet and legacy communication lines go to GRIND  36 . A separate line may provide legacy communication from GRIND  36  to PCN  34 . 
     Turning now to  FIG. 2 , certain additional details of a BRCM  24  can be more fully explained. As shown, BRCM  24  has, in this embodiment, a pair of 5×2 Ethernet switches respectively indicated at  44   a  and  44   b . One port of the respective switches is used to connect them together. Other ports may be used for connection to other BRCMs or to the external sources noted above. For example, one port of switch  44   b  connects an OAM microcontroller  46 . Similarly, one port of switch  44   a  can be used to connect another OAM or a protocol processor module (PPM). A PPM could provide an interconnection to a tank monitoring system, for example, used to track inventory and health of the underground fuel storage tanks and piping systems. Other auxiliary systems could be connected as well. 
     The PPM module (which can include an application(s) running on microprocessor also used for other purposes) can be implemented in both the BRCM in the back room, as well as the DCMs located within dispensers. For example, the PPM can host applications relative to back room functions and/or back room-to-dispenser communication functions. These applications can include control of locally special devices and/or implement special multiplexing/de-multiplexing logic. For example, one application is to implement a current loop protocol over TCP/IP multiplexer. Another example is implementation of proxies at dispensers or in the back rooms, for example, interception of certain protocol information relating to dispensing of fuels to enable real-time evaluation of forecourt-wide fuel flow rates. In the BRCM, these PPM applications can run on the OAM microcontroller  46 , or on an external processor connected to the BRCM Ethernet interface. Similarly, relative to  FIG. 2 , the PPM can run on a microprocessor within the DCM  32  or on the CRIND  36 . Integrating the PPM within the communications elements has significant advantages regarding integration of software applications, and overall system cost. 
     In the embodiment of  FIG. 2 , four ports of each switch are connected via Ethernet to a respective DSL modulation interface device (such as DSL interface  48 ). Each such interface may include a suitable chip set, such as a chip set supplied by Lantiq. Under the control of a FPGA controller  50 , these interfaces convert the Ethernet signal to a signal suitable for transmission over legacy field wiring (as indicated by the eight lines labeled “Four VDSL2 Interfaces (to D-box).” 
     A variety of different modulation or multiplexing technologies may be used within the scope of the present invention. This embodiment, however, advantageously utilizes a form of DSL technology specially adapted for this application. In particular, each DSL interface within a BRCM  24  is preferably controlled on an individual basis to have “modified” band plans. In other words, the respective interface is adapted to provide a preferred band plan for the specific set of field wiring (also referred to as legacy cable) over which the high bandwidth signals will pass. In this regard, the controller  50  tests the connection and selects an appropriate set of spectral frequency ranges to disallow from use. Existing DSL technology utilizes DSP technology to adaptively weight each of numerous frequency ranges within the overall spectrum as to their use, based on noise or other interfering signals analyzed at the time the DSL link “trains.” In addition, controller  50  can specifically disallow any use of certain frequency ranges at the lower end of the spectrum, to enable existing low data rate current loop or RS422 signals to operate on the legacy cable without interference. The set of disallowed frequency ranges can be selected or programmed on a per-link basis, based on the required bandwidth of the low rate signal or other requirements. For example, the lowest 600 kHz segment of the DSL band may be disallowed for better error rate performance of both legacy and broadband signaling and ease filtering requirements. This threshold may vary depending on location or other requirements of a particular installation, such as accommodation of specified legacy current loop, RS485 or other interface data rates, or specific RF or noise profiles of other signals present in the wiring conduit. 
     Referring now to  FIG. 3 , the eight DSL communication lines from BRCM  24  are connected to a TBM  22 . As can be seen, they pass through a high pass filter (and isolation channel)  52  before being combined with the output of a low pass filter  54 . The combined signal is passed to (or from) a respective forecourt device over the legacy field wiring (or “OLC” for “over legacy cable”). In this case, high pass filter  52  is preferably implemented in capacitors only. For example, two capacitors may be used (one in each leg of the DSL signal) with a capacitance C that is small enough not to limit appreciably the signal over the desired range of frequencies. Preferably, however, the capacitors will have a sufficient voltage rating (e.g., 3500 volts) so that the field wiring can occupy an electrical power feed conduit as noted above. 
     Additionally, the DSL signals may pass through the isolation channel by being coupled through a suitable transformer. The transformer is configured to be suitable for passing the desired range of frequencies, and should also have a sufficient voltage rating (e.g., at least 3500 volts) so that the field wiring can occupy an electrical power feed conduit as noted above. These isolation techniques can also be applied to alternate modem technologies, such as HomePlug. 
     For the legacy data, electrical isolation is provided by an opto-isoiator module  56 . In particular, module  56  may be connected on a “low voltage” side to a two-wire POS (or EDH). For POS systems that use RS422, a suitable RS422 isolator  58  is also preferably provided. It will thus be appreciated that that the capacitors of high pass filter  52  (or the isolation transformer of high pass filter  52 ), opto-isolator  56  and RS422 isolator  58  divide TBM22 into a “low voltage isolation island” and a “high voltage isolation island.” Not all the components within the “high voltage isolation island” need to be rated to operate at high voltage, only those components that interface directly to the conduit. However, placing the non-high voltage rated components in the “high voltage isolation island” allows them to be used (in accordance with applicable standards and regulations) with wiring that passes through power feed conduit. In detail, UL standards require all communications wiring in the conduit to have a 3500 volts breakdown rating. 
     On the “high voltage” side, opto-isolator  56  feeds to two-wire current sources  60 . In this case, current sources  60  comprise eight individual current source circuits that buffer the two-wire messages to the field wiring. Preferably, the current source drive level may be selectable by jumper to support a variety of different POS units. Jumpers or other disconnect methods can also be provided to allow isolating the conduit interfaces during servicing. In addition, low pass filter  54  is connected between current sources  60  and the field wiring. Preferably, the low pass filter may be implemented as an inductor only. The inductance L is preferably chosen so that it will not appreciably distort the two-wire signal, but will also not add appreciably to the DSL signal. 
     In an alternative embodiment, the BRCM may interface directly to a high voltage conduit in an installation where broadband communications over legacy cable are not necessary. In such an embodiment, one skilled in the art will appreciate that the isolation circuitry described above in TBM  22  may instead be located in the BRCM. Moreover, several components shown in  FIG. 1  providing and combining the legacies signals (such as POS  12  and distribution box  14 ) need not be provided. 
       FIG. 4  illustrates certain additional details regarding a preferred embodiment of DCM  22 . As one skilled in the art will appreciate, many components of DCM  22  are analogous to those in TBM  22 . In this regard, an OLC signal coming from field wiring is provided to a summer  62  to which a low pass filter  64  and a high pass filter (and isolation channel)  66  are connected. As can be seen, the legacy data from low pass filter  64  is passed to a transient current limiter (TCL) circuit  68  and then to the legacy electronics. As one skilled in the art will appreciate, the legacy data may include pump control data, payment data or both depending on the particular installation. In some cases, for example, pump control data, and payment data, may be sent over separate sets of legacy wiring, in which case the DSL signal will be combined with one but not the other. 
     The legacy electronics will typically already include optical isolation components such that summer  62 , low pass filter  64 , and TCL  68  can be thought of as a “high voltage isolation island.” In the illustrated embodiment, TCL  68  is provided to protect the legacy electronics from failure due to the necessary filtering. In particular, the interaction between the low pass and high pass filters and the optical isolation circuit in the dispenser could create transient high current in the optical coupler circuit. These high current transients could occur, for example, when the dispenser coupler closes the current loop, as in transmitting data. This is prevented by TCL circuit  68 , which is in series with the dispenser&#39;s optical coupler. The TCL actively reduces the maximum current to levels which are suitable for the optical coupler components. 
     The TCL is preferably configured to be bypassed as necessary or desirable for non-current loop or other applications that do not need transient current limiting. This can be done with wiring options at the interface connector, jump jacks or under bill of materials modification, or software control. 
     The transformers in high pass filter  66  function to isolate low frequency signals on the “high voltage isolation island” from passing to the “low voltage isolation island”, and to couple high frequency DSL signals from the “high voltage isolation island” to the “low voltage isolation island.” Like TBM  22 , this provides the isolation necessary if the field wiring is installed in power feed conduit. The resulting DSL signal is provided to a converter  70 , which converts between DSL and Ethernet. As a result, the signals on the other side of converter  70  are Ethernet signals which can be used for various high bandwidth applications, such as those discussed above. 
       FIG. 5  illustrates an alternative embodiment of a DCM that utilizes either HomePlug or DSL technology, as necessary or desired. The function and operation of most components of this DCM will be apparent from the above discussion. In the case of HomePlug, one skilled in the art will appreciate that the BRCM in that case would also utilise HomePlug rather than DSL. 
     In this embodiment, however, the DCM includes a microcontroller  80  that implements a PPM  82 . (A similar PPM may also be implemented in the back room electronics in addition to or instead of PPM  82 .) As can be seen, microcontroller  80  is connected via Ethernet to the main OLC transceiver  84 . In addition, microcontroller  80  exposes GPIO, serial interface(s) and USB interface to the external world. Preferably, microcontroller  80  acts not simply as a serial-to-Ethernet converter, but rather contains specific application(s) able to control locally special devices and/or implement special multiplexing/de-multiplexing logic. For example, one application is to implement a two wire over TCP/IP multiplexer application. 
     As should be apparent to those skilled in the art, many advantages are realized by a communication system in accordance with the present invention. For example, a broadband forecourt communication system in accordance with the present invention enables numerous applications not previously available on the fueling forecourt, such as high definition video. In addition, a network of fueling sites may be configured to utilise one central controller for controlling media systems, surveillance systems, and mission-critical sensing systems. A central controller connected to the Internet can download and modify content to be pushed in real time to any device on the forecourt at any fueling site, where each device can utilise different content simultaneously. Further, remote monitoring and diagnostics can be affected to the communications subsystem of any fueling site. In this regard, system operator and maintenance functions can be accomplished locally and remotely via HTTP connections. Moreover, existing low data rate communications (such as current loop and RS-422) can be replaced with high data rate communications utilising TCP/IP. 
     While one or more preferred embodiments of the invention have been described above, it should be understood that any and all equivalent realizations of the present invention are included within the scope and spirit thereof. The embodiments depicted are presented by way of example only and are not intended as limitations upon the present invention. Thus, it should be understood by those of ordinary skill in this art that the present invention is not limited to these embodiments since modifications can be made. For example, aspects of one embodiment may be combined with aspects of other embodiments to yield still further embodiments. Therefore, it is contemplated that any and all such embodiments are included in the present invention as may fall within the scope and spirit thereof.