Control device, control method, and program

Abstract

To provide a mechanism that can improve the accuracy of estimating positional relationship in a multipath environment.SOLUTION: A control device includes a control unit that estimates the position of another communication device, based on an integrated value of received power of an impulse radio signal received within a predetermined time width by a communication device that is placed inside a target space partitioned by an object and receives the impulse radio signal including one or more pulses transmitted by the other communication device.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a control device, a control method, and a program. [Background technology]

[0002] In recent years, a technique has been developed for estimating the positional relationship between a transmitter and a receiver by transmitting and receiving wireless signals. For example, Patent Document 1 discloses a technique for estimating the distance between a transmitter and a receiver based on the power attenuation rate of the received power relative to the transmitted power. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-085719 Summary of the Invention [Problem to be solved by the invention]

[0004] However, since the received power can vary significantly in a multipath environment, there is a risk that the accuracy of distance estimation will decrease with the technique disclosed in Patent Document 1.

[0005] Therefore, the present invention has been made in consideration of the above problems, and an object of the present invention is to provide a mechanism that can improve the estimation accuracy of the positional relationship in a multipath environment. [Means for solving the problem]

[0006] In order to solve the above problem, according to one aspect of the present invention, there is provided a control device that is placed inside a target space partitioned by an object, receives an impulse radio signal including one or more pulses transmitted by another communication device, and estimates a position of the other communication device based on an integrated value of received power of the impulse radio signal received by the communication device within a predetermined time width.

[0007] In order to solve the above problem, according to another aspect of the present invention, there is provided a control device that is placed inside a target space partitioned by an object, receives an impulse radio signal including one or more pulses transmitted by another communication device, and estimates a position of the other communication device based on an integrated value of a channel impulse response (CIR) value calculated based on the impulse radio signal received by the communication device over a predetermined time width.

[0008] In order to solve the above problem, according to another aspect of the present invention, there is provided a control method executed by a computer, the control method including: a communication device that is placed inside a target space partitioned by an object, receiving an impulse radio signal including one or more pulses transmitted by another communication device, and estimating a position of the other communication device based on an integrated value of received power of the impulse radio signal received by the communication device over a predetermined time width.

[0009] In order to solve the above problem, according to another aspect of the present invention, there is provided a control method executed by a computer, the control method including: a communication device that is placed inside a target space partitioned by an object and receives an impulse radio signal including one or more pulses transmitted by another communication device, and estimating a position of the other communication device based on an integrated value over a predetermined time width of a CIR value calculated based on the impulse radio signal received by the communication device.

[0010] In order to solve the above problem, according to another aspect of the present invention, there is provided a program for causing a computer to function as a control unit that is placed inside a target space partitioned by an object, receives an impulse radio signal including one or more pulses transmitted by another communication device, and estimates a position of the other communication device based on an integrated value of received power of the impulse radio signal received by the communication device over a predetermined time width.

[0011] In order to solve the above problem, according to another aspect of the present invention, there is provided a program for causing a computer to function as a control unit that is placed inside a target space partitioned by an object, receives an impulse radio signal including one or more pulses transmitted by another communication device, and estimates a position of the other communication device based on an integrated value over a predetermined time width of a CIR value calculated based on the impulse radio signal received by the communication device. Effect of the Invention

[0012] As described above, according to the present invention, a mechanism is provided that can improve the accuracy of estimating a positional relationship in a multipath environment. [Brief description of the drawings]

[0013] [Figure 1] 1 is a block diagram showing an example of a functional configuration of a control system according to an embodiment of the present invention; [Diagram 2] FIG. 2 is a diagram for explaining detailed functions of the control system according to the present embodiment. [Diagram 3] FIG. 2 is a diagram for explaining detailed functions of the control system according to the present embodiment. [Figure 4] FIG. 2 is a diagram for explaining detailed functions of the control system according to the present embodiment. [Diagram 5] 5 is a flowchart showing an example of a flow of processing executed by the control system according to the present embodiment. [Figure 6] 11A and 11B are diagrams for explaining modified examples of the arrangement of communication devices. [Figure 7] 11A and 11B are diagrams for explaining modified examples of the arrangement of communication devices. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this specification and the drawings, components having substantially the same functional configurations are designated by the same reference numerals, and duplicated explanations will be omitted.

[0015] In addition, in this specification and drawings, when multiple identical components are to be described separately, alphabets or the like may be added to the end of the reference numerals. On the other hand, when there is no need to distinguish between multiple identical components, the alphabets or the like may be omitted and a description common to all of the multiple identical components may be given.

[0016] <1. Embodiment> <1.1. System configuration example> First, an example of the functional configuration of a control system 1 according to an embodiment of the present invention will be described.

[0017] FIG. 1 is a block diagram showing an example of the functional configuration of a control system 1 according to an embodiment of the present invention.

[0018] A control system 1 according to this embodiment includes a moving object 10 and a portable device 20, as shown in FIG.

[0019] As shown in FIG. 1, a mobile object 10 according to this embodiment is equipped with a communication device 110, a control device 120, and a controlled device 130.

[0020] Moreover, the portable device 20 according to this embodiment is equipped with a communication device 210 and has a control application 220 installed therein.

[0021] (Mobile 10) The moving body 10 according to this embodiment may be, for example, a vehicle such as a car, an aircraft, or a ship.

[0022] (Communication device 110) The communication device 110 according to this embodiment performs wireless communication with a communication device 210 mounted on the portable device 20 in accordance with a prescribed communication standard.

[0023] The prescribed communication standard may be, for example, one that uses an impulse radio signal. An impulse radio signal is a signal that includes a short, wideband pulse. Specifically, the prescribed communication standard may be one that uses an ultra-wide band (UWB) radio signal.

[0024] However, the prescribed communication standard is not limited to the above example, and may be set arbitrarily.

[0025] The mobile object 10 may be equipped with one or more communication devices 110 .

[0026] (Control device 120) The control device 120 according to this embodiment includes a control unit that controls the execution of a prescribed operation by the controlled device 130 based on the result of communication by the communication device 110 .

[0027] The functions of the control device 120 according to the present embodiment are realized by various processors. The functions of the control device 120 according to the present embodiment will be described in detail later.

[0028] (Controlled device 130) The controlled device 130 according to this embodiment may be any of various devices that execute a specified operation under the control of the control device 120.

[0029] As shown in FIG. 1, when the controlled device 130 is mounted on the moving body 10, the controlled device 130 may be, for example, a locking / unlocking device that locks / unlocks a door provided on the moving body 10 as the above-mentioned specified operation.

[0030] However, controlled device 130 and the prescribed operation are not limited to the above example.

[0031] For example, controlled device 130 may be an engine, in which case the prescribed action may be to allow or restrict engine starting.

[0032] Also, for example, controlled device 130 may be a lighting device. In this case, the specified action may be to turn on or off the light.

[0033] (Portable Devices 20) The portable device 20 according to this embodiment is carried by a user of the moving object 10 (for example, the owner of the moving object 10, or a person authorized by the owner to use the moving object 10, etc.).

[0034] The portable device 20 according to this embodiment may be, for example, a smartphone, a tablet, a wearable device, or the like.

[0035] (Communication device 210) The communication device 210 according to this embodiment performs wireless communication with the communication device 110 mounted on the mobile object 10 in accordance with a prescribed communication standard.

[0036] (Control Application 220) The control application 220 according to this embodiment includes at least a program for controlling the above-mentioned wireless communication by the communication device 210.

[0037] An example of the functional configuration of the control system 1 according to the present embodiment has been described above. Note that the functional configuration described above with reference to Fig. 1 is merely an example, and the functional configuration of the control system 1 according to the present embodiment is not limited to this example.

[0038] The functional configuration of the control system 1 according to this embodiment can be flexibly modified according to the specifications, operation, and the like.

[0039] <1.2.Function details> Next, functions of the control system 1 according to this embodiment will be described in detail with reference to FIGS.

[0040] 2 to 4 are diagrams for explaining detailed functions of the control system 1 according to this embodiment.

[0041] 2, a communication device 110 is disposed on a ceiling portion inside a vehicle cabin 11 of a moving object 10. The vehicle cabin 11 is an example of a target section partitioned by an object. The vehicle is an example of an object partitioning the vehicle cabin 11.

[0042] However, the vehicle interior 11 is also partitioned by members that transmit radio waves, such as the window glass 12. Therefore, even if the portable device 20 is located outside the vehicle interior 11, the portable device 20 and the communication device 110 can communicate with each other.

[0043] The portable device 20 transmits an impulse radio signal S including one or more pulses. The communication device 110 receives the impulse radio signal S transmitted by the portable device 20.

[0044] The control device 120 then estimates the position of the portable device 20 based on the received power (e.g., Received Signal Strength Indicator (RSSI)) of the impulse radio signal S received by the communication device 110. At this time, the control device 120 estimates the position of the portable device 20 based on an integrated value of the received power of the impulse radio signal S received by the communication device 110 in a predetermined time width T. With this configuration, it is possible to improve the accuracy of estimating the position of the portable device 20, as described below.

[0045] Graph G shows a time series transition of the received power of the impulse radio signal S received by the communication device 110, with the horizontal axis representing time and the vertical axis representing the received power. Referring to graph G shown in Fig. 2, it can be seen that a plurality of waveforms W1 to W3 are received at intervals in the time direction.

[0046] W1 is a waveform that corresponds to a direct wave. A direct wave is a signal that is received by the receiving side directly (i.e., without being reflected) via the shortest path between the transmitting side and the receiving side.

[0047] W2 and W3 are waveforms corresponding to reflected waves. A reflected wave is a signal received by the receiving side via a path that includes reflection.

[0048] As described above with reference to Patent Document 1, the received power may vary significantly in a multipath environment. For this reason, if the position of the portable device 20 is estimated based only on the received power of the waveform W1 corresponding to the direct wave, the estimation accuracy may decrease.

[0049] By using the impulse radio signal S, it becomes possible to separate multipath waves in terms of time, improving the estimation accuracy. However, when the portable device 20 is located near the moving body 10 even if it is outside the vehicle interior 11, there is a risk that the portable device 20 will be erroneously estimated to be located inside the vehicle interior 11. This is because in such a positional relationship, the distance between the transmitter and the receiver is close, so the received power is large, and the difference with the received power when the portable device 20 is located inside the vehicle interior 11 is small.

[0050] Therefore, the control device 120 according to this embodiment estimates the position of the portable device 20 based on the integrated value of the received power of the impulse radio signal S received in a predetermined time width T, i.e., the integrated value of the received power of the waveforms W1 to W3. With this configuration, the relationship in magnitude between the received powers corresponding to the relationship in magnitude between the transmission and reception distances becomes clear enough to be easily distinguished by the integration, so that it is possible to improve the accuracy of estimating the position of the portable device 20.

[0051] 2, the predetermined time width T is longer than the time width of a pulse contained in the impulse radio signal S. With this configuration, it becomes possible to integrate the received power of multiple pulses and use the integrated power for position estimation.

[0052] On the other hand, the predetermined time width T is shorter than the transmission interval of the impulse radio signal S. With this configuration, even if the portable device 20 transmits the impulse radio signal S multiple times, the target of the integration can be limited to the received power when the impulse radio signal S is transmitted once. As a result, it is possible to suppress the variation in the accuracy of the location estimation of the portable device 20.

[0053] Incidentally, estimation based on the accumulated value is effective precisely because the transmitted and received signal is an impulse radio signal S. This is because multiple impulse radio signals S received at the receiving end after passing through multiple paths can be separated in the time domain, as shown in graph G of Fig. 2. If the transmitted and received signal were a sine wave, signals with opposite phases would cancel each other out, making it difficult to separate multiple sine waves received at the receiving end after passing through multiple paths in the time domain, and making estimation based on the accumulated value difficult.

[0054] 3, when the portable device 20 is located inside the vehicle interior 11, the impulse radio signal S that has passed through many paths is received by the communication device 110 as a direct wave indicated by a solid line or a reflected wave indicated by a dashed line. As a result, as shown in graph G in FIG 3, a waveform W1 corresponding to a direct wave and waveforms W2 and W3 corresponding to reflected waves are received by the communication device 110, and the integrated value in a predetermined time width T becomes large.

[0055] On the other hand, as shown in Fig. 4, when the portable device 20 is located outside the vehicle interior 11, the impulse radio signal S that has passed through fewer paths compared to the example shown in Fig. 3 is received by the communication device 110 as a direct wave shown by a solid line or a reflected wave shown by a dashed line. This is because the signal does not reach the communication device 110 unless it has passed through the window glass 12. As a result, as shown in graph G in Fig. 4, a waveform W1 corresponding to a direct wave and a waveform W2 corresponding to a reflected wave are received by the communication device 110, and the integrated value in a predetermined time width T becomes smaller compared to the example shown in Fig. 3.

[0056] In this way, the difference in the integrated value of the received power in the predetermined time width T between when the portable device 20 is located inside the vehicle compartment 11 and when it is located outside the vehicle compartment 11 becomes larger than the difference in the received power of only the direct wave.

[0057] Therefore, the control device 120 estimates that the portable device 20 is located inside the vehicle interior 11 when the integrated value of the received power of the impulse radio signal S received by the communication device 110 in the specified time width T is greater than a specified threshold. On the other hand, the control device 120 estimates that the portable device 20 is located outside the vehicle interior 11 when the integrated value of the received power of the impulse radio signal S received by the communication device 110 in the specified time width T is smaller than or equal to the specified threshold.

[0058] This configuration makes it possible to improve the accuracy of estimating whether the portable device 20 is located inside or outside the vehicle interior 11. In particular, even if the communication device 110 is placed in a position that can be seen from outside the vehicle interior 11, such as on the ceiling inside the vehicle interior 11, it is possible to accurately distinguish whether the portable device 20 is located inside or outside the vehicle interior 11.

[0059] <1.3. Processing flow> Next, an example of the flow of processing executed by the control system 1 according to the present embodiment will be described with reference to FIG.

[0060] FIG. 5 is a flowchart showing an example of the flow of processing executed by the control system 1 according to this embodiment.

[0061] As shown in FIG. 5, first, the portable device 20 transmits an impulse radio signal S, and the communication device 110 receives the impulse radio signal S transmitted from the portable device 20 (step S102).

[0062] Next, the control device 120 calculates an integrated value of the received power of the impulse radio signal S received by the communication device 110 during the predetermined time duration T (step S104).

[0063] Next, the control device 120 estimates the presence area of ​​the portable device 20 based on the calculated integrated value (step S106). For example, the control device 120 estimates that the portable device 20 is located inside the vehicle interior 11 when the integrated value is greater than a predetermined threshold value, and estimates that the portable device 20 is located outside the vehicle interior 11 when the integrated value is not greater than a predetermined threshold value.

[0064] Then, the control device 120 controls the operation of the controlled device 130 based on the estimation result of the presence area of ​​the portable device 20 (step S108). For example, when the control device 120 estimates that the portable device 20 is located inside the vehicle interior 11, the control device 120 permits the engine to start.

[0065] <2. Supplementary Information> Although the preferred embodiment of the present invention has been described in detail above with reference to the accompanying drawings, the present invention is not limited to such an example. It is clear that a person having ordinary knowledge in the technical field to which the present invention pertains can conceive of various modified or altered examples within the scope of the technical ideas described in the claims, and it is understood that these also naturally belong to the technical scope of the present invention.

[0066] (First Modification) The portable device 20 may transmit a plurality of impulse radio signals S. In this case, the communication device 110 receives a plurality of impulse radio signals S. Then, the control device 120 may calculate an integrated value in a predetermined time width T for each of the plurality of impulse radio signals S received by the communication device 110, and estimate the position of the portable device 20 based on the calculated integrated values.

[0067] At this time, the control device 120 may estimate the position of the portable device 20 based on a statistical value of a plurality of integrated values ​​calculated for a plurality of impulse radio signals S. An example of the statistical value here is an average value, a weighted average value, or a median value.

[0068] According to this configuration, it is possible to further improve the accuracy of estimating the position of the portable device 20.

[0069] (Second Modification) A plurality of communication devices 110 may be disposed inside the vehicle interior 11. In this case, the control device 120 may calculate an integrated value in a predetermined time width T for each of a plurality of impulse radio signals S received by the plurality of communication devices 110, and estimate the position of the portable device 20 based on the calculated integrated values.

[0070] In this case, the control device 120 may estimate that the portable device 20 is located inside the vehicle interior 11 when all of the multiple integrated values ​​calculated for the multiple communication devices 110 are greater than a predetermined threshold. On the other hand, the control device 120 may estimate that the portable device 20 is located outside the vehicle interior 11 when at least a part of the multiple integrated values ​​calculated for the multiple communication devices 110 are smaller than or equal to the predetermined threshold.

[0071] According to this configuration, it is possible to further improve the accuracy of estimating the position of the portable device 20.

[0072] It should be noted that this modification and the first modification may be combined.

[0073] (Third Modification) The control device 120 may calculate a channel impulse response (CIR) based on the impulse radio signal S received by the communication device 110. The control device 120 may calculate the CIR by performing a sliding correlation between the received signal and a known transmission signal. The control device 120 may then estimate the position of the portable device 20 based on an integrated value of the CIR value over a predetermined time span T.

[0074] The process by the control device 120 according to this modification is similar to that of the above embodiment, except that the CIR value is used instead of the received power.

[0075] According to this configuration, the magnitude relationship of the CIR values ​​corresponding to the magnitude relationship of the distance between the transmitter and the receiver becomes clear enough to be easily distinguished by integration, so that the accuracy of estimating the position of the portable device 20 can be improved.

[0076] It should be noted that this modification may be combined with the first modification and / or the second modification.

[0077] (Variations in Arrangement of Communication Device 110) 2 to 4, the communication device 110 may be disposed on the ceiling of the vehicle interior 11. In this case, it is possible to ensure a wide communication area with the portable device 20 outside the vehicle interior 11.

[0078] However, the arrangement of the communication device 110 is not limited to this example. Modified examples of the arrangement of the communication device 110 will be described with reference to FIGS.

[0079] Fig. 6 is a diagram for explaining a modified arrangement of the communication device 110. As shown in Fig. 6, a plurality of communication devices 110 (110L and 110R) may be arranged on the ceiling of the vehicle interior 11 at positions spaced apart in the left-right direction of the vehicle as the moving body 10. With such an arrangement, it is possible to secure a wide communication area with the portable device 20 outside the vehicle interior 11 and improve the accuracy of estimating the position of the portable device 20.

[0080] Specifically, since communication device 110L is disposed to the left of the center and close to the left window glass 12L, it is possible to ensure a wide communication area with portable device 20 in the left direction. Similarly, since communication device 110R is disposed to the right of the center and close to the right window glass 12R, it is possible to ensure a wide communication area with portable device 20 in the right direction.

[0081] In addition, with such an arrangement, it is possible to refer to multiple received powers obtained by multiple communication devices 110, which makes it possible to further improve the accuracy of estimating whether the portable device 20 is located inside or outside the vehicle compartment 11.

[0082] Fig. 7 is a diagram for explaining another example of the arrangement position of the communication device 110. As shown in Fig. 7, a plurality of communication devices 110 (110F and 110B) may be arranged on the ceiling of the vehicle interior 11 at positions spaced apart in the front-rear direction of the vehicle as the moving body 10. With such an arrangement, it is possible to secure a wide communication area with the portable device 20 outside the vehicle interior 11 and improve the estimation accuracy of the position of the portable device 20.

[0083] In particular, since communication device 110F is disposed forward from the center, it is possible to ensure a wide communication area with portable device 20 in the forward direction. Similarly, since communication device 110B is disposed rearward from the center, it is possible to ensure a wide communication area with portable device 20 in the rearward direction. When moving body 10 is long in the front-to-rear direction like a vehicle, this arrangement is advantageous in that a long communication area can be ensured in the front-to-rear direction.

[0084] In addition, with such an arrangement, it is possible to refer to multiple received powers obtained by multiple communication devices 110, which makes it possible to further improve the accuracy of estimating whether the portable device 20 is located inside or outside the vehicle compartment 11.

[0085] (others) The application of the present invention is not limited to the moving body 10. In other words, the communication device 110 may be placed inside a target space partitioned by an object, and the placement of the communication device 110 is not limited to inside the vehicle cabin 11. For example, the communication device 110 may be placed inside a room, and the control device 120 may estimate whether the portable device 20 is located inside or outside the room.

[0086] The series of processes by each device described in this specification may be realized using any of software, hardware, and a combination of software and hardware. The programs constituting the software are stored in advance, for example, in a recording medium (more specifically, a non-transient storage medium readable by a computer) provided inside or outside each device. Then, each program is read into a random access memory (RAM) when executed by a computer that controls each device described in this specification, and executed by a processing circuit such as a central processing unit (CPU). The recording medium is, for example, a magnetic disk, an optical disk, a magneto-optical disk, a flash memory, etc. The computer program may be distributed, for example, via a network without using a recording medium. The computer may be an application specific integrated circuit such as an application specific integrated circuit (ASIC), a general-purpose processor that executes a function by reading a software program, or a computer on a server used in cloud computing. The series of processes by each device described in this specification may be processed in a centralized manner by a single computer, or may be processed in a distributed manner by multiple computers. Furthermore, in each of the above embodiments, two or more communication means present in one device may be physically realized by one medium.

[0087] In addition, the processes described in this specification using flowcharts or sequence diagrams do not necessarily have to be performed in the order shown in the drawings. Some processing steps may be performed in parallel. In addition, additional processing steps may be employed, and some processing steps may be omitted. [Explanation of symbols]

[0088] 1: control system, 10: moving body, 11: vehicle interior, 12: window glass, 110: communication device, 120: control device, 130: controlled device, 20: portable device, 210: communication device, 220: control application

Claims

1. a control unit that is arranged within a target space partitioned by an object, receives an impulse radio signal including one or more pulses transmitted by another communication device, and estimates a position of the other communication device based on an integrated value of received power of the impulse radio signal received by the communication device within a predetermined time width; A control device comprising:

2. the predetermined time width is longer than a time width of the pulse included in the impulse radio signal and shorter than a transmission interval of the impulse radio signal. The control device according to claim 1 .

3. When the integrated value is greater than a predetermined threshold, the control unit estimates that the other communication device is located inside the target space. The control device according to claim 1 .

4. The communication device receives a plurality of the impulse radio signals; the control unit calculates the integrated value for each of the plurality of impulse radio signals received by the communication device, and estimates a position of the other communication device based on the plurality of integrated values. The control device according to claim 1 .

5. A plurality of the communication devices are disposed within the target space, the control unit calculates the integrated value for each of the plurality of impulse radio signals received by the plurality of communication devices, and estimates a position of the other communication device based on the plurality of integrated values. The control device according to claim 1 .

6. the object is a vehicle; The target space is a vehicle cabin. The control device according to any one of claims 1 to 5.

7. The communication device is disposed on the ceiling of the vehicle compartment. The control device according to claim 6.

8. A plurality of the communication devices are arranged on a ceiling of the vehicle compartment at positions spaced apart in the left-right direction of the vehicle. The control device according to claim 6.

9. A plurality of the communication devices are arranged on a ceiling of the vehicle compartment at positions spaced apart in a front-rear direction of the vehicle. The control device according to claim 6.

10. a control unit that is arranged within a target space partitioned by an object, receives an impulse radio signal including one or more pulses transmitted by another communication device, and estimates a position of the other communication device based on an integrated value of a channel impulse response (CIR) value calculated based on the impulse radio signal received by the communication device over a predetermined time width; A control device comprising:

11. 1. A computer-implemented control method, comprising: a communication device that is disposed within a target space partitioned by an object and receives an impulse radio signal including one or more pulses transmitted by another communication device, and estimates a position of the other communication device based on an integrated value of received power of the impulse radio signal received by the communication device within a predetermined time width; A control method comprising:

12. 1. A computer-implemented control method, comprising: a communication device that is disposed within a target space partitioned by an object and receives an impulse radio signal including one or more pulses transmitted by another communication device, and estimates a position of the other communication device based on an integrated value of a CIR value calculated based on the impulse radio signal received by the communication device over a predetermined time period; A control method comprising:

13. Computer, a control unit that is arranged within a target space partitioned by an object, receives an impulse radio signal including one or more pulses transmitted by another communication device, and estimates a position of the other communication device based on an integrated value of received power of the impulse radio signal received by the communication device within a predetermined time width; A program to function as a

14. Computer, a control unit that is arranged within a target space partitioned by an object, receives an impulse radio signal including one or more pulses transmitted by another communication device, and estimates a position of the other communication device based on an integrated value of a CIR value calculated based on the impulse radio signal received by the communication device over a predetermined time width; A program to function as a

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