Patent Publication Number: US-2021195407-A1

Title: Systems and methods for wirelessly pairing medical devices using non-numeric key patterns

Description:
FIELD 
     The present disclosure generally relates to systems and methods for wirelessly pairing medical devices using non-numeric key patterns, and more particularly to systems and methods for wirelessly pairing medical devices using non-numeric key patterns, particularly where one of the medical devices has four or more LEDS and no numeric display. 
     BACKGROUND 
     Wireless, activity between devices is becoming more and more prevalent, including within the medical devices context in which wires become tangled and problematic, as well as limiting the mobility of a patient and/or medical devices. One mechanism or protocol for providing wireless connectivity between devices that has been widely accepted is Bluetooth®, which provide pairing between devices by successfully entering a six digit authentication key (each comprised of a number 0-9) corresponding to one device into a second device, whereby a matching entry is required for the two devices to successfully pair. 
     SUMMARY 
     This Summary is provided to introduce a selection of concepts that are further described below in the Detailed Description. This Summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter. 
     One embodiment of the present disclosure generally relates to a method for wirelessly pairing a medical acquisition device and a host device. The method includes requesting an authentication key associated with the medical acquisition device to be entered into the host device, and producing a key pattern on the medical acquisition device representative of the authentication key. In this embodiment, the key pattern is non-numeric. The method further includes providing a plurality of targets on the host device, and receiving selections of the plurality of targets to form an entry pattern on the host device. The method further includes wirelessly pairing the medical acquisition device and the host device only when the entry pattern is determined to match the key pattern on the medical acquisition device. 
     Another embodiment generally relates to a method for wirelessly pairing a medical acquisition device and a host device within a time limit. The method includes providing a plurality of targets on the host device and requesting the medical acquisition device to sequentially produce six key patterns, each of the six key patterns being non-numeric and made of selections among a plurality of individual indicators. The method further includes sequentially receiving on the host device, one after each of the six key patterns is produced on the medical acquisition device, six entry patterns each comprised of selections among the plurality of targets. The method further includes indicating how many of the six entry patterns have been received by the host device, and indicating a remaining time until the time limit is reached. The method further includes wirelessly pairing the medical acquisition device and the host device only when the sequence of six entry patterns is determined to match the sequence of six key patterns on the medical acquisition device before the time limit is reached. 
     Another embodiment generally relates to a system for wirelessly pairing a medical acquisition device and a host device. A plurality of LEDs is operatively coupled to the medical acquisition device, where each of the plurality of LEDs is selectively illuminated to collectively form at least six key patterns, and where the at least six key patterns are non-numeric. A display device is operatively coupled to the host device, where the display device displays a plurality of targets thereon, and where each of the plurality of targets is selectable. An input device is operatively coupled to the host device, where the input device is operable to select among the plurality of targets to collectively form entry patterns. A computer system compares the at least six key patterns to the entry patterns corresponding thereto. The medical acquisition device and the host device wireless pair only when the at least six key patterns are determined to match the entry patterns corresponding thereto. 
     Various other features, objects and advantages of the disclosure will be made apparent from the following description taken together with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present disclosure is described with reference to the following Figures. 
         FIG. 1  depicts a front view of an exemplary medical acquisition device and host device wirelessly paired according to the present disclosure; 
         FIG. 2A  is front view of an exemplary interface for the embodiment of medical acquisition device shown in  FIG. 1 ; 
         FIG. 2B  provides a listing of key patterns enterable from an interface of an alternative embodiment of medical acquisition device configured for pairing according to the present disclosure; 
         FIG. 3  is a front view of the medical acquisition device and host device of  FIG. 1 , now shown in the process of pairing according to the present disclosure; 
         FIG. 4  depicts an exemplary process flow for pairing a medical device and host device according to the present disclosure, such as may be followed for the pairing shown in process in  FIG. 3 ; and 
         FIG. 5  depicts an exemplary control system as may be incorporated within the medical acquisition device and/or host device according to the present disclosure. 
     
    
    
     DETAILED DISCLOSURE 
     The present disclosure generally relates to systems and methods for authenticating Bluetooth® or like wireless pairing protocols between two devices, such as a medical acquisition device and a host device. In particular, the present disclosure relates to authentication methods in which the input capabilities of one of the devices, such as the medical acquisition device, are limited. Bluetooth® is one such example of a wireless pairing protocol and has been widely accepted across many industries. 
     Security for Bluetooth® devices is tied to the pairing method employed. Bluetooth® provides for a wide range of security profiles, starting with no security, to authenticated pairing with Man In The Middle (MITM) protection. For medical devices, it is desired (if not required) to have the highest level of security that is possible, while also minimizing the cost and design constraints in the product or products being paired. The passkey entry pairing method of Bluetooth® is a pairing method that provides authenticated pairing with MITM protection. This method requires one device with display capability, and another device with key entry capability, to accomplish pairing. The device with the display capability must be capable of displaying a six digit pairing key, and likewise the other device with the key entry capability must be capable of entering these same six digit pairing keys. 
     However, the inventor has identified that many devices in which secure pairing is highly desirable are not suited for the pairing methods presently known. In the example of an ECG acquisition device, such as GE Healthcare&#39;s CAM CONNECT  14 , the only indicators on the device are LEDs (in certain examples, tri-colored LEDS) provided to indicate the status of each ECG electrode connected thereto. For example, the LEDs may indicate that the ECG electrode is successfully connected, is disconnected, or has some error condition associated therewith. 
     Another challenge that is faced by users is the pairing timeout that is mandated by the Bluetooth® specification (referred to as the SMP Timeout). This timeout is implemented for security reasons to prevent the pairing protocol from stalling due to the lack of user input. The timeout clock starts from the instant when the initiating device sends the pairing request or the responding device receives the pairing request. If the pairing process is not completed within 30 seconds of the start of the timer, the pairing fails and the user has to re-initiate pairing. 
     The inventor has recognized that most users are not even aware of this timeout, or its value as mandated by the Bluetooth® specification. If a user is slow to enter the six digit key and the pairing timeout expires, resulting in failed pairing, users are often left wondering what caused the failure. 
     As will become apparent, the present systems and methods provide for Bluetooth® passkey entry pairing between devices that do not have the sufficient capability to display a six digit number, and are therefore unable to pair with a host device according to systems and methods presently known in the art. In particular, the inventor has recognized that other indicators provided on such a device, which are used for some other operation of the device rather than in a pairing process, may be repurposed to serve as representations of numeric numbers, and therefore may be used to provide pairing between these existing devices and a host device using the Bluetooth® protocol, non-numerically. 
       FIG. 1  depicts one such system  1  for pairing a medical acquisition device  10  with a host device  60  according to the present disclosure. In the present example, the medical acquisition device  10  is an ECG device having a main unit  12  and leads  50 , which receive data from a patient by connecting the electrode couplers  52  of the leads  50  to electrodes positioned on a patient in the manner known in the art. The main unit  12  comprises a control system  14  for providing the functions of the ECG device, as well as for providing a pairing process to be discussed below. This includes an authentication key generator  16 , which is provided within or operatively in conjunction with the control system  14 . A main unit  12  further includes a pairing button  18  that initiates that pairing process between the medical acquisition device  10  and the host device  60 , as well as an operating button  20  for controlling the standard operation of the ECG device in acquiring data from the patient. It should be recognized that the other buttons or forms of selection are also anticipated by the present disclosure. 
     The main unit  12  further includes a communication device  22 , which in the present example is used for wirelessly communicating between the medical acquisition device  10  and the host device  60 , particularly with a communication device  64  associated therewith. 
     As shown in  FIG. 1 , the medical acquisition device  10  in the present example does not include a digital display or alphanumeric indicator. However, the medical acquisition device  10  does have an indicator interface  30  that provides individual indicators  40  positioned on an anatomical graphic  32 , which correspond to positions for electrode placement for obtaining ECG signals. In certain examples of medical acquisition devices  10  presently known in the art, these individual indicators  40  are tri-color status LEDs that each indicate an ECG signal quality for one of the leads  50 , with ten individual indicators  40  being provided as specific indicators  11410 . As will be discussed below, the inventor has identified that although these individual indicators  40  are presently used only for the standard operation of an ECG device, the fact that there are ten individual indicators  40  may be exploited such that each of the individual indicators  40  is assigned to one numeric digit 0-9. In this manner, the individual indicators  40  may be repurposed during the pairing process to represent an authentication key for medical acquisition device  10  that is otherwise not equipped to do so. 
       FIG. 1  further depicts an exemplary host device  60  shown receiving information from a medical acquisition device  10  wirelessly paired therewith, particularly received via the communication device  64  discussed above. The host device  60  includes a control system  62 , which like control system  14  of the medical acquisition device  10  may be configured in the manner shown for the control system  100  of  FIG. 5  (discussed further below). The host device  60  includes a display device  66 , which in the present example is two computer monitors each displaying an interface  68  and displaying medical data  69 . User input devices  72  are also operatively connected to the host device  60 , which in the present example include a keyboard  74  and a mouse  76 , which as will be discussed below provides for movement and selection via a curser  78  (see  FIG. 3 ). 
       FIG. 2A  further depicts the indicator interface  30  from the medical acquisition device  10  shown in  FIG. 1 , but now with each of the ten individual indicators  40  being assigned to a specific indicator I 1 -I 10 , respectively. In the example shown, each of the specific indicators I 1 -I 10  is shown darkened, which might represent a LED being on or illuminated. Having all ten individual indicators  40  darkened in certain embodiments serves as an indication that the pairing process is starting, or that an entry has been received by the host device  60  and that a new pattern will then be displayed, for example. The particular configuration of which specific indicators I 1 -I 10  are selected (e.g. illuminated) is also referred to herein as a key pattern  42 , whereby at least one of the specific indicators I 1   410  is illuminated in each key pattern  42 . For example, a first specific key pattern KP 1  may correspond to only the first of the specific indicators I 1  being selected, a second specific key pattern KP 2  distinct from the first when only the second of the specific indicators  12  is selected, and the like. 
     As shown in  FIG. 2B , it is further possible that key patterns  42  may be provided whereby more than one specific individual indicator I 1 -I 10  is illuminated, allowing all ten digits 0-9 to be represented with fewer than ten individual indicators  40 . In the example shown, four individual indicators  40  are used, whereby ten key patterns  42  (listed as specific key patterns KP 1 -KP 10 ) are each assigned to or represent a unique numeric equivalent  44  corresponding to the authentication key, referred to as specific numeric equivalents N 1 -N 10 . On this basis, it will be recognized that medical acquisition devices  10  (or other devices, medical or not) may be used to generate key patterns representative of digits in an authentication key with as few as four individual indicators  40  being present therewith. 
     In further examples, all ten key patterns  42  may be provided via a single individual indicator  40 , provided it can indicate a sufficient number of distinct indications. For example, a device capable of displaying at least ten unique colors could be used and mapped to digits as follows: Light blue—0, Dark blue—1, Light Green—2, Dark Green—3, Red—4, Orange—5, Yellow—6, Purple—7, White—8, and Pink—9. 
       FIG. 3  depicts a medical acquisition device  10  and host device  60  now in the process of wirelessly pairing, rather than transmitting ECG data as shown in  FIG. 1 . In the present example, only the first specific indicator I 1  is shown to be selected on the indication interface  30  of the medical acquisition device  10 , whereby all other individual indicators  40  remain unselected. As will be discussed further below with respect to the process flow in  FIG. 4 , this indicator interface  30  may therefore be configured to correspond to a key pattern  42  having a numeric  44  of one. However, it is not necessary that the user is aware of the particular assignment of key patterns  42  to numeric equivalence  44 . Instead, as shown on the interface  68  of the host device  60 , the user merely identifies which of the individual indicators  40  is selected on the medical acquisition device  10 , and subsequently selects the corresponding target  80  on a pairing display  70  shown on the display device  66  during the pairing process. 
     It will be recognized that the targets  80  correspond to the individual indicators  40  on the medical acquisition device  10  such that there are ten specific targets T 1 -T 10  corresponding to the ten specific indicators I 1 -I 10 . The user then selects the one or more targets  80  in the pairing display  70  that corresponds to those selected on the medical acquisition device  10 , constituting an entry pattern  82  that should match the key pattern  42  of the medical acquisition device  10 . As discussed above, this may entail selecting more than one target  80 , depending upon which of the individual indicators  40  on the medical acquisition device  10  are selected. The control system  62  (see  FIG. 1 ) then compares whether the entry pattern  82  provided by the user on the pairing display  70  matches the key pattern  42  provided on the medical acquisition device  10 , which allows the pairing process to proceed when properly matched. As will be discussed further below, this would be repeated until all digits have been properly entered into the host device  60 , which for a standard Bluetooth® protocol would be 6 digits total. 
     The embodiment of  FIG. 3  further depicts a progress display  90  that shows the progress of the pairing process in real-time, which is not presently provided with Bluetooth® pairing processes known in the art. In particular, Bluetooth® pairing processes are limited to thirty seconds maximum for entering all digits corresponding to the authentication key to complete the wireless pairing. However, users today are not aware of how much time is remaining, and therefore are subject to time outs and having to start the wireless pairing process over. 
     In the exemplary progress display  90  shown, a pairing time indicator  91  is provided, as well as a pairing progress indicator  95 . The pairing time indicator  91  in the present example is a running bar depicting the amount of pairing time elapsed  92  relative to the pairing time remaining  93  and the overall pairing time limit  94 , which is as previously discussed is generally thirty seconds. It will be recognized that once the initiation of the pairing process has started, for example via the pair button  18  on the medical acquisition device  10 , the pairing time elapsed  92  runs from left to right until thirty seconds have elapsed and the process times out, unless pairing has completed before this time. This provides a much needed indication for the operator as to the pace for entering entry patterns  82  into the host device  60 . 
     The progress display  90  further includes a pairing progress indicator  95 , which shows the pairing matches already complete  96 , which pairing match (for example of the six total required) is in progress  97 , and how many pairing matches are remaining  98  before the pairing process is completed. By providing this pairing process indicator  95 , the user may compare this status to the pairing time indicator  91  to identify the portion of the overall pairing process remaining to be completed. 
       FIG. 4  depicts an exemplary process flow  200  for pairing a medical acquisition device  10  (or other wireless device) with a host device  60 , such as may be followed in the pairing shown in  FIG. 3 . The process begins in step  202  with the host device  60  requesting a six digit authentication key, whereby each digit is assigned a number 0-9, and whereby the authentication key is associated with a medical acquisition device  10 . As discussed above, this request happens in the response to a wireless pairing process initiation, such as by pressing the pair button  18  on the medical acquisition device  10 . Also in step  202 , a match count is started at zero. In step  204 , the medical acquisition device  10  produces a key pattern  42  comprised of one or more selected individual indicators  40 , whereby the key pattern  42  represents a digit from the authentication key to be entered into the host device  60 . In step  206 , the host device  60  provides selectable targets  80  corresponding to the individual indicators  40  and further receives selections to form an overall entry pattern  82  intended to correspond to the key pattern  42 . The individual pairing digit corresponding to each entry pattern  82  entered on the host device  60  is the transmitted to the medical acquisition device  10 . 
     The control system  14  within the acquisition device  10  then determines whether the entry pattern  82  entered into the host device  60  matches the key pattern  42  provided with the medical acquisition device  10 . If no match is confirmed in step  210 , it is then determined whether there is any time remaining in step  212 , as discussed above with respect to the standard time out of thirty seconds. If there is no time remaining, the process times out in step  214 . If instead there is time remaining, the process continues with retrying a selection of targets  80  for the entry pattern  82 , for example after clearing out the erroneous previous selection. 
     If instead it is confirmed that the entry pattern  82  entered into the host device  60  matches the key pattern  42  of the medical acquisition device  10  in step  210 , the prior match count is increased by one in step  216 , and is then determined in step  218  whether all 6 matches corresponding to the authentication key have been completed. If so, the authentication key has been successfully entered in its entirety and the wireless pairing process is completed in step  220 . If instead not all six matches have been completed, the process continues to step  222  to determine whether time remains before the time out. If not, the process is timed out once again at step  214 . However, if time is remaining in step  222  and not all six matches have been completed as determined at step  218 , the process continues whereby the next sequential key pattern  42  is provided with a medical acquisition device  10 , for subsequent entry into the host device  60  as an entry pattern  82 . 
     Additional information is now provided for an exemplary control system  100 , which is shown in  FIG. 5 . Certain aspects of the present disclosure are described or depicted as functional and/or logical block components or processing steps, which may be performed by any number of hardware, software, and/or firmware components configured to perform the specified functions. For example, certain embodiments employ integrated circuit components, such as memory elements, digital signal processing elements, logic elements, look-up tables, or the like, configured to carry out a variety of functions under the control of one or more processors or other control devices. The connections between functional and logical block components are merely exemplary, which may be direct or indirect, and may follow alternate pathways. 
     The control system  100  may be a computing system that includes a processing system  110 , memory system  120 , and input/output (I/O) system  130  for communicating with other devices, such as input devices  99  and output devices  101 , either of which may also or alternatively be stored in a cloud  102 . The processing system  110  loads and executes an executable program  122  from the memory system  120 , accesses data  124  stored within the memory system  120 , and directs the system  1  to operate as described in further detail below. 
     The processing system  110  may be implemented as a single microprocessor or other circuitry, or be distributed across multiple processing devices or sub-systems that cooperate to execute the executable program  122  from the memory system  120 . Non-limiting examples of the processing system include general purpose central processing units, application specific processors, and logic devices. 
     The memory system  120  may comprise any storage media readable by the processing system  110  and capable of storing the executable program  122  and/or data  124 . The memory system  120  may be implemented as a single storage device, or be distributed across multiple storage devices or sub-systems that cooperate to store computer readable instructions, data structures, program modules, or other data. The memory system  120  may include volatile and/or non-volatile systems, and may include removable and/or non-removable media implemented in any method or technology for storage of information. The storage media may include non-transitory and/or transitory storage media, including random access memory, read only memory, magnetic discs, optical discs, flash memory, virtual memory, and non-virtual memory, magnetic storage devices, or any other medium which can be used to store information and be accessed by an instruction execution system, for example. 
     The inventor has identified that others have attempted to institute wireless pairing without the use of an alphanumeric display, but have not solved the problems defined above. In particular, these prior art solutions (for example, U.S. Pat. No. 7,831,207) do not fully integrate within conventional Bluetooth® procedures. In addition, no presently known solutions are capable of reliably performing in the context of a Bluetooth® procedure that includes a thirty second time limit for providing all six authentication key entries. In the disclosed methods of U.S. Pat. No. 7,831,207, a light on the device is caused to blink for the number of times corresponding to the digit to be displayed. For example, to display digit “1”, the light blinks a single time, twice for “2,” and the like. There is an inter-group pause between the blinks to enable the user to distinguish between these groupings of blinks, which must be a longer pause than an intra-group pause between each blink sequence to distinguish between different digits of the pairing key. The patent specifies an interval of 0.5 seconds as the intra-group pause between blinks, and an inter-group pause of three seconds before the start of the next blink sequence. Several variations of this scheme are outlined in the patent, such as audible beeps or vibrations. 
     However, the inventor has identified that the methods of U.S. Pat. No. 7,831,207 are problematic. First, there is no mechanism for indicating via blinks, audible beeps, or vibrations the number zero, which prevents these methods from being directly applied to an authentication key possible under standard Bluetooth® protocols (which can have one or more zeros, even 000000). There is also a high possibility of error, whereby an authentication code of 999999 would necessitate correctly counting 9×6=54 light blinks, audible beeps, or vibrations. If even one blink, beep, or vibration is missed, the entire pairing process will necessarily fail. 
     Moreover, the methods of U.S. Pat. No. 7,831,207 are infeasible, or more likely impossible, under the Bluetooth® standards of today. When U.S. Pat. No. 7,831,207 was filed in 2007, the SMP timeout requirement of thirty seconds had not yet been implemented. Using the example of the authentication key 999999, along with the exemplary pauses provided in the patent as described above, it would be impossible to enter the key within the thirty second limit. Specifically, the intra-group pauses would include nine flashes, beeps, or vibrations×0.5 seconds×six digits for a total of twenty-seven seconds. In addition, the process would require five inter-group pauses×three seconds for a total of fifteen seconds. Therefore, the method would take a minimum of forty-two seconds, which is beyond the maximum of thirty seconds. Moreover, this ignores any time for the user to process these flashes, beeps, or vibrations and successfully input them into the receiving device. In short, the methods of U.S. Pat. No. 7,831,207 are not viable for Bluetooth® pairing under the standards of today, necessitating the systems and methods presently disclosed. 
     The foregoing has principally focused on Bluetooth® pairing methods referred to as “passkey entry pairing” in which one device knows and displays a key, which the user has to enter into the other device. The presently disclosed system and methods are also applicable to other methods of Bluetooth® pairing, including another referred to as “numeric comparison”. In Numeric Comparison pairing methods, both devices know the pairing key and the user has to provide a YES/NO answer to each digit displayed on either device. 
     In the example of the pairing key being 123456, both devices simultaneously derive this key. The medical acquisition device  10  lights up the LED corresponding to digit 1. The host device  60  lights up the LED corresponding to digit 1 on its graphic. The user verifies that both devices agree on the first digit of the pairing key sequence. The user presses a button on the medical acquisition device  10  corresponding to “YES”. The medical acquisition device  10  moves on to display the next digit. The user presses a button/control on the graphic on the host device  60  that corresponds to YES. The host device  60  moves on to display the next digit. If six YES entries are made on each device, the pairing succeeds. If both devices do not agree on a pairing digit, the user selects NO on either one of the devices and the pairing process fails. 
     For this pairing method to be implemented, in addition to a way of representing the pairing digits one-by-one on either device, two buttons corresponding to YES/NO are needed on each device. The two buttons on the medical acquisition device  10  described above (pairing button  18  and operating button  20 ) can be repurposed to temporarily serve these functions during the pairing process, for example. 
     The functional block diagrams, operational sequences, and flow diagrams provided in the Figures are representative of exemplary architectures, environments, and methodologies for performing novel aspects of the disclosure. While, for purposes of simplicity of explanation, the methodologies included herein may be in the form of a functional diagram, operational sequence, or flow diagram, and may be described as a series of acts, it is to be understood and appreciated that the methodologies are not limited by the order of acts, as some acts may, in accordance therewith, occur in a different order and/or concurrently with other acts from that shown and described herein. For example, those skilled in the art will understand and appreciate that a methodology can alternatively be represented as a series of interrelated states or events, such as in a state diagram. Moreover, not all acts illustrated in a methodology may be required for a novel implementation. 
     This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to make and use the invention. Certain terms have been used for brevity, clarity, and understanding. No unnecessary limitations are to be inferred therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes only and are intended to be broadly construed. The patentable scope of the invention is defined by the claims and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have features or structural elements that do not differ from the literal language of the claims, or if they include equivalent features or structural elements with insubstantial differences from the literal languages of the claims.