JP2006186475A - Communication method, and terminal and base station apparatus utilizing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a communication method which instructs a user of the position of a terminal, at which the communication quality is improved so as to facilitate understanding by the user. <P>SOLUTION: An acquisition section 58 acquires position coordinates and information, with respect to a communication state, such as the SNR and a delay spread from each of a plurality of terminals. A selection section 62 selects a terminal with the SNR and the delay spread to a prescribed condition closer than the SNR and the delay spread of a terminal of a processing object, on the basis of the SNR and the delay spread. A deriving section 64 derives a direction toward the selected terminal for the terminal of the processing object, on the basis of the coordinates of the position of the terminal selected by the selection section 62. A notice section 66 generates a packet signal that includes the direction derived by the deriving section 64. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to communication technology, and more particularly, to a communication method for communicating in a service area, and a terminal device and a base station device using the same.

In a communication system including a base station device and a terminal device, communication quality is determined according to a radio propagation environment between the base station device and the terminal device. In addition, signal strength, SNR (Signal to Noise Ratio), delay profile, delay spread, and the like are used as indexes for representing the radio propagation environment. In order to improve the convenience of the user who uses the terminal device, the terminal device displays the signal strength (see, for example, Patent Document 1). In such a case, the user moves to a position where the radio propagation environment is preferable for communication while looking at the displayed signal strength.
JP 2004-128735 A

  In general, if the signal strength increases, the communication quality is improved, but the communication quality may not be improved. For example, the terminal apparatus includes an adaptive equalizer, and the delayed wave component included in the received signal exceeds the equalizable range of the adaptive equalizer. That is, this is a case where there is a delayed wave exceeding a period corresponding to a plurality of taps in the adaptive equalizer. Such a situation is generally realized in an environment where a delayed wave is received after being reflected a plurality of times. In such a case, in order to improve the communication quality, the user should move to a position where the power of the delayed wave is smaller than the power of the direct wave.

  Under such circumstances, the present inventor has come to recognize the following problems. When only the signal strength is displayed on the terminal device, it is generally difficult for the user to detect a position where the power of the delayed wave is smaller than the power of the direct wave. Further, even when a delay spread or a delay profile is displayed on the terminal device, in order to find a position where the power of the delayed wave is smaller than the power of the direct wave, Expert knowledge about the propagation environment is required. This is because the degree of improvement in communication quality may be small even when approaching the base station apparatus.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a communication method for instructing a user where to improve communication quality so that the user can easily understand, and a terminal apparatus and a base station apparatus using the communication method. Is to provide.

  In order to solve the above problems, a base station apparatus according to an aspect of the present invention includes a communication unit that communicates with each of a plurality of terminal apparatuses, information on a communication state for each of the plurality of terminal apparatuses, A communication state closer to a predetermined condition than a communication state in any of a plurality of terminal devices, based on an acquisition unit that acquires position information for each, and information on a communication state acquired in the acquisition unit A selection unit that selects the terminal device, and a notification unit that notifies the position information corresponding to the terminal device selected by the selection unit to any of the plurality of terminal devices via the communication unit.

  The “communication state” is an index indicating the quality of communication, and corresponds to the radio propagation environment, the quality of communication, and the like. The former includes signal strength, SNR, delay profile, delay spread, and the like, and the latter includes bit error rate, transmission rate, and the like. The “predetermined condition” is a condition that improves the quality of communication, but may not be necessarily improved but may be a condition that there is a high possibility of improvement. “Close to a predetermined condition” means that if a predetermined condition is defined by a threshold value, the threshold value is satisfied, and if the predetermined condition is not defined by a threshold value, it is more predetermined. It is to approach the condition of.

  According to this aspect, the position information of the terminal device that is closer to the predetermined condition than the terminal device is notified to any one of the plurality of terminal devices. Position information that is close to the above condition can be notified, and a position that is close to the predetermined condition can be instructed to the user of the terminal device.

  Another aspect of the present invention is also a base station apparatus. The apparatus includes: a communication unit that communicates with each of a plurality of terminal devices; an acquisition unit that acquires information about a communication state for each of the plurality of terminal devices; and a position information for each of the plurality of terminal devices. Based on the information on the acquired communication state, the selection unit that selects a terminal device in a communication state closer to a predetermined condition than the communication state in any of the plurality of terminal devices, and the acquisition unit acquires Based on the position information, for any one of the plurality of terminal devices, a derivation unit for deriving a direction to the terminal device selected by the selection unit, and a communication unit, among the plurality of terminal devices One of them includes a notification unit that notifies the direction derived by the deriving unit.

  According to this aspect, the direction to the terminal device closer to the predetermined condition than the terminal device is notified to any one of the plurality of terminal devices. A direction that is close to the above condition can be notified, and a direction that is close to a predetermined condition can be instructed to the user of the terminal device.

  The deriving unit derives a distance between any one of the plurality of terminal devices and the terminal device selected by the selecting unit based on the position information acquired by the acquiring unit, and the notifying unit includes the plurality of terminal devices. The distance derived by the deriving unit may be notified to any of the above. In this case, since the distance to the terminal device that is closer to the predetermined condition than the terminal device is also notified to any of the plurality of terminal devices, any one of the plurality of terminal devices The distance close to the condition can be notified, and the user of the terminal device can be instructed the distance close to the predetermined condition.

  Any of the plurality of terminal devices in the selection unit may be a terminal device that requests the communication unit to start communication. In this case, a position close to a predetermined condition can be instructed to the user of the terminal device from the timing of starting communication.

  Yet another embodiment of the present invention is a terminal device. This device is a terminal device that communicates with a base station device, a derivation unit that derives a state of communication with the base station device, an acquisition unit that acquires a current position of the terminal device, a communication state, and A notification unit that notifies the base station apparatus of the current position, and a position derived in the base station apparatus, and the communication state is a predetermined condition among a plurality of terminal apparatuses communicating with the base station apparatus A receiving unit that receives the position of a nearby terminal device from the base station device, a calculation unit that calculates a direction to the position received by the receiving unit with respect to the position acquired by the acquiring unit, and a direction calculated by the calculating unit An instruction unit that instructs the display device to display the above.

  According to this aspect, based on the position of the terminal apparatus received from the base station apparatus and close to a predetermined condition, a direction close to the predetermined condition is derived and displayed. A direction close to a predetermined condition can be instructed to the user of the terminal device.

  Yet another embodiment of the present invention is also a terminal device. This device is a terminal device that communicates with a base station device, a derivation unit that derives a state of communication with the base station device, an acquisition unit that acquires a current position of the terminal device, a communication state, and A notification unit that notifies the base station device of the current position, and a communication state of a plurality of terminal devices that are in a direction derived from the base station device and are communicating with the base station device A reception unit that receives a direction from the base station device to a direction of a nearby terminal device; and an instruction unit that instructs the display device to display the direction received by the reception unit.

  According to this aspect, since the direction to the terminal device that is received from the base station device and is close to the predetermined condition is displayed, the user of the terminal device is close to the predetermined condition. You can indicate the direction.

  Yet another embodiment of the present invention is a communication method. This method is based on a communication state for each of a plurality of terminal devices communicating with a base station device, and a terminal in a communication state closer to a predetermined condition than a communication state in any of the plurality of terminal devices. A device is selected, and the position information corresponding to one of the plurality of terminal devices and the position information of the selected terminal device are used to transfer the selected terminal device from one of the plurality of terminal devices. A direction is derived, and the derived direction is output from any of the plurality of terminal devices.

  Yet another embodiment of the present invention is also a communication method. This method is based on the step of communicating with each of a plurality of terminal devices, the step of acquiring information and position information regarding the communication status for each of the plurality of terminal devices, and the information regarding the communication status acquired in the acquiring step. And selecting a terminal device in a communication state closer to a predetermined condition than a communication state in any of the plurality of terminal devices, and selecting in any of the plurality of terminal devices And notifying location information corresponding to the terminal device.

  Yet another embodiment of the present invention is also a communication method. The method includes a step of communicating with each of a plurality of terminal devices, a step of acquiring information and position information regarding a communication state for each of the plurality of terminal devices, and a information regarding the communication state acquired in the acquiring step. And a step of selecting a terminal device in a communication state closer to a predetermined condition than a communication state in any of the plurality of terminal devices, and a plurality of position devices based on the position information acquired in the acquiring step. A step of deriving a direction to the terminal device selected in the step of selecting to any one of the terminal devices, and a step of notifying the direction derived in the step of deriving to any of the plurality of terminal devices And comprising.

  The deriving step also derives and notifies the distance between any of the plurality of terminal devices and the terminal device selected in the selecting step based on the position information obtained in the obtaining step. The distance derived in the deriving step may be notified to any of the plurality of terminal devices. Any of the plurality of terminal devices in the selecting step may be a terminal device that requests the start of communication.

  Yet another embodiment of the present invention is also a communication method. The method includes a step of deriving a state of communication with the base station device, a step of obtaining a current position of the terminal device, a step of notifying the base station device of the state of communication and the current position, A step of receiving, from the base station apparatus, a position of a terminal apparatus that is a position derived in the station apparatus and in which a communication state is close to a predetermined condition among a plurality of terminal apparatuses communicating with the base station apparatus And a step of calculating a direction to the received position in the receiving step with respect to the position acquired in the acquiring step, and a step of instructing the display device to display the direction calculated in the calculating step.

  Yet another embodiment of the present invention is also a communication method. The method includes a step of deriving a state of communication with the base station device, a step of obtaining a current position of the terminal device, a step of notifying the base station device of the state of communication and the current position, The direction to the position of a terminal device whose communication state is close to a predetermined condition among a plurality of terminal devices that are derived in the station device and are communicating with the base station device. And a step of instructing the display device to display the direction received in the receiving step.

  It should be noted that any combination of the above-described constituent elements and a conversion of the expression of the present invention between a method, an apparatus, a system, a recording medium, a computer program, etc. are also effective as an aspect of the present invention.

  ADVANTAGE OF THE INVENTION According to this invention, the position where communication quality improves can be instruct | indicated to a user so that a user can understand easily.

  Before describing the present invention in detail, an outline will be described. An embodiment of the present invention relates to a communication system including a base station device and a terminal device. The base station device connects a plurality of terminal devices. Such a terminal device is operated by a user. In the base station apparatus and the terminal apparatus according to the present embodiment, a position where communication quality is improved is instructed to the user as follows. The terminal apparatus receives the packet signal from the base station apparatus, measures the SNR of the received packet signal, and calculates a delay spread from the received packet signal. Furthermore, the terminal device has a GPS (Global Positioning System) reception function, and measures the position of the terminal device. The terminal apparatus notifies the base station apparatus of information related to SNR, delay spread, and position. Here, the terminal apparatus includes an adaptive equalizer, and thus measures the SNR and delay spread that affect the communication quality of the adaptive equalizer.

  The base station apparatus selects a terminal apparatus having an SNR and delay spread closer to a predetermined condition than the SNR and delay spread of the terminal apparatus to be processed. Here, the predetermined condition corresponds to, for example, an SNR larger than the SNR of the terminal device to be processed and a delay spread smaller than the delay spread of the terminal device to be processed. The base station device derives the direction to the position of the selected terminal device with respect to the position of the terminal device to be processed, and further determines the distance between the terminal device to be processed and the selected terminal device. To derive. The base station device notifies the terminal device of the derived direction and distance. The terminal device displays the received direction and distance on the display device. The user moves while viewing the displayed direction and distance.

  FIG. 1 shows a configuration of a communication system 100 according to an embodiment of the present invention. The communication system 100 includes a base station device 10, a first terminal device 12a, a second terminal device 12b, a third terminal device 12c, and a fourth terminal device 12d, which are collectively referred to as a terminal device 12. Further, a service area 14 is formed by the base station apparatus 10.

  The terminal device 12 communicates with the base station device 10. Further, the terminal device 12 includes an adaptive equalizer therein. Here, the terminal device 12 may be configured as a single device or may be configured in a form connected to a personal computer. Below, it demonstrates as what is comprised as a single apparatus. Note that, as illustrated, the plurality of terminal devices 12 exist in the service area 14 formed by the base station device 10, but the positions of the plurality of terminal devices 12 are different. Therefore, the radio propagation environments between each of the plurality of terminal devices 12 and the base station device 10 are also different from each other. As a result, some of the plurality of terminal devices 12 have good communication quality and some have poor communication quality. The terminal device 12 measures the SNR and delay spread of the signal received from the base station device 10 as a radio propagation environment with the base station device 10. Furthermore, the terminal device 12 has a GPS reception function, and also measures the coordinates of the position where the terminal device 12 exists. The coordinates are measured in the form of latitude and longitude, for example. The terminal device 12 transmits the measured SNR, delay spread, and position coordinates to the base station device 10.

  The base station device 10 communicates with a plurality of terminal devices 12. The base station apparatus 10 stores the SNR, delay spread, and position coordinates received from the terminal apparatus 12. Furthermore, the base station apparatus 10 prescribes | regulates predetermined conditions with respect to SNR and delay spread. Here, the predetermined condition is defined such that the SNR is large and the delay spread is small. Such a condition corresponds to the case where the communication quality is improved by the adaptive equalizer provided in the terminal device 12. That is, it can be said that the radio propagation environment is more suitable for the adaptive equalizer. For example, when the first terminal device 12a is the terminal device 12 to be processed, the base station device 10 has an SNR larger than that of the first base station device 10a, and the delay spread of the first terminal device 12a. The terminal device 12 having a smaller delay spread is selected.

  When the selected terminal device 12 is the second terminal device 12b, the base station device 10 detects the coordinates of the position of the second terminal device 12b. Moreover, since the base station apparatus 10 also detects the coordinate of the position of the 1st terminal device 12a, the direction to the position of the 2nd terminal device 12b with respect to the position of the 1st terminal device 12a from these, and 1st The distance between the position of the terminal device 12a and the position of the second terminal device 12b is calculated. The base station apparatus 10 notifies the calculated direction and distance to the first terminal apparatus 12a. When receiving the direction and distance from the base station apparatus 10, the first terminal apparatus 12a displays them on a display unit (not shown). At that time, the first terminal device 12a displays, for example, so as to urge the user who uses the first terminal device 12a to move by “distance” and “direction”. As a result, the user can move to a position where the communication quality is improved. The base station device 10 is connected to a network (not shown) and relays data between the terminal device 12 and the network.

  FIG. 2 shows a configuration of the first terminal apparatus 12a. The first terminal device 12 a includes a terminal antenna 20, a radio unit 22, a display unit 24, a GPS antenna 26, a GPS processing unit 28, and a control unit 30. The radio unit 22 includes an RF unit 32, a modem unit 34, a baseband processing unit 36, a derivation unit 38, an acquisition unit 40, a notification unit 42, a reception unit 44, and an instruction unit 46. Here, although the 1st terminal device 12a is demonstrated, the other terminal devices 12 shall have the same structure.

  The terminal antenna 20 receives a radio frequency signal from the base station apparatus 10 of FIG. 1 as a reception operation. Further, the terminal antenna 20 transmits a radio frequency signal to the base station apparatus 10 as a transmission operation. Here, a signal received by the terminal antenna 20 and a signal to be transmitted have a packet signal format, and a preamble which is a known signal is arranged at the head portion thereof. Note that the timing of the reception operation and the transmission operation is controlled by the control unit 30. Here, the number of terminal antennas 20 is 1, but the number may be larger.

  As a reception operation, the RF unit 32 performs frequency conversion on a radio frequency signal received by the terminal antenna 20 and derives a baseband signal. The RF unit 32 outputs a baseband signal to the modem unit 34. In general, baseband signals are formed by in-phase and quadrature components, so they should be transmitted by two signal lines. Here, for clarity of illustration, only one signal line is used. Shall be shown. An AGC and A / D converter are also included. As a transmission operation, the RF unit 32 converts the frequency of the baseband signal from the modem unit 34 to derive a radio frequency signal. The RF unit 32 outputs a radio frequency signal to the terminal antenna 20. Further, a PA (Power Amplifier) and a D / A converter are also included.

  The modem unit 34 performs demodulation on the baseband signal from the RF unit 32 as reception processing. The modem unit 34 outputs the demodulated signal to the baseband processing unit 36. The modem unit 34 includes an adaptive equalizer, and performs equalization on the baseband signal when demodulating. Here, the adaptive equalizer is configured by a plurality of taps, but may be configured by an arbitrary type. Examples thereof include a linear equalizer, DFE (Decision Feedback Equalizer), MLSE (Maximum Likelihood Sequence Estimation), and DDFSE (Delayed Decision Feedback Equor Equipped). An adaptive algorithm for estimating the tap count of the adaptive equalizer may be arbitrary, and examples thereof include an LMS (Least Mean Square) algorithm and an RLS (Recursive Last Square) algorithm. The adaptive equalizer sets the tap coefficient while using the preamble arranged at the head portion of the packet signal. Further, the modem unit 34 performs modulation as transmission processing. The modem unit 34 outputs the modulated signal to the RF unit 32.

  The baseband processing unit 36 outputs a signal demodulated by the modem unit 34 to the application that operates in the first terminal apparatus 12a as the reception process and that operates in the processing unit (not shown). The application performs predetermined processing on the received signal and outputs it to the display unit 24 and the like. An example of an application is a call function, an e-mail, and a browser. Here, description of the details of the application is omitted. Further, the baseband processing unit 36 outputs a signal received from the application to the modem unit 34.

  The deriving unit 38 receives the received baseband signal from the modem unit 34 and derives the SNR and the delay spread as the state of communication with the base station apparatus 10 from the received baseband signal. The received baseband signal may be a signal after being demodulated, a signal before being demodulated, or a radio frequency signal or intermediate frequency before being converted to baseband. The signal may also be That is, any signal that reflects the radio propagation environment may be used. Here, it is assumed that the baseband signal is not demodulated. The deriving unit 38 derives the SNR from the RSSI of the received baseband signal. The deriving unit 38 derives a delay profile from the received baseband signal, and derives a delay spread from the derived delay profile. Here, as for a method for deriving the delay spread from the delay profile, a known technique may be used, and thus the description thereof is omitted. The deriving unit 38 stores a preamble pattern included in the head portion of the packet signal in advance, and derives a delay profile from the received baseband signal based on correlation processing or an adaptive algorithm.

  The GPS processing unit 28 receives signals from a plurality of GPS satellites (not shown) via the GPS antenna 26, and performs positioning based on the received signals, so that the current status of the first terminal device 12a is obtained. Get the position. Here, since positioning by GPS is a well-known technique, description is abbreviate | omitted. At least the GPS processing unit 28 acquires coordinates indicated by latitude and longitude as the current position.

  The notification unit 42 receives the SNR and the delay spread from the derivation unit 38, and receives the position coordinates from the acquisition unit 40. The notification unit 42 generates a packet signal while including the SNR, delay spread, and position coordinates. Further, the notification unit 42 transmits the generated packet signal to the base station device 10 via the baseband processing unit 36, the modem unit 34, the RF unit 32, and the terminal antenna 20.

  After receiving the packet signal from the notification unit 42, the reception unit 44 receives the packet signal from the base station apparatus 10 via the terminal antenna 20, the RF unit 32, the modem unit 34, and the baseband processing unit 36. In the packet signal, the SNR and the delay spread are close to predetermined conditions in the direction derived in the base station apparatus 10 and among the plurality of terminal apparatuses 12 communicating with the base station apparatus 10. The direction to the position of the terminal device 12 is included. The packet signal also includes the distance between the position of the first base station apparatus 10a and the position of the terminal apparatus 12 whose SNR and delay spread are close to predetermined conditions. These directions and distances correspond to directions and distances that improve reception quality in the first terminal apparatus 12a. The predetermined conditions for the SNR and delay spread are as described above, and details thereof will be described later.

  The instruction unit 46 instructs the display unit 24 to display the direction and distance received by the reception unit 44. The display unit 24 displays the received direction and distance. FIG. 3 shows display contents on the display unit 24. As shown in the figure, the display unit 24 displays “Please move 10 m to the west”, but “west” corresponds to the direction accepted, and “10 m” corresponds to the distance accepted. The display unit 24 performs display that prompts the user to move. The user can improve the communication quality in the first terminal apparatus 12a by moving according to the display. The control unit 30 controls timing and the like in the first terminal device 12a.

  This configuration can be realized in terms of hardware by a CPU, memory, or other LSI of an arbitrary computer, and in terms of software, it is realized by a program having a reservation management function loaded in memory. The functional block realized by those cooperation is drawn. Accordingly, those skilled in the art will understand that these functional blocks can be realized in various forms by hardware only, software only, or a combination thereof.

  FIG. 4 shows the configuration of the base station apparatus 10. The base station device 10 includes a base station antenna 50, an RF unit 52, a modem unit 54, a baseband processing unit 56, an acquisition unit 58, a storage unit 60, a selection unit 62, a derivation unit 64, a notification unit 66, and an IF unit 68. Including. The base station apparatus 10 is connected to the network 72.

  As a receiving operation, the base station antenna 50 receives radio frequency signals from the plurality of terminal apparatuses 12 shown in FIG. The base station antenna 50 transmits a radio frequency signal to the plurality of terminal devices 12 as a transmission operation. Note that the timing of the reception operation and the transmission operation is controlled by the control unit 70. Although the number of base station antennas 50 is 1 here, the number may be larger.

  As a reception operation, the RF unit 52 performs frequency conversion on a radio frequency signal received by the base station antenna 50 and derives a baseband signal. The RF unit 52 outputs a baseband signal to the modem unit 54. An AGC and A / D converter are also included. As a transmission operation, the RF unit 52 converts the frequency of the baseband signal from the modem unit 54 and derives a radio frequency signal. The RF unit 52 outputs a radio frequency signal to the base station antenna 50. A PA and D / A converter are also included.

  The modem unit 54 demodulates the baseband signal from the RF unit 52 as a reception process. The modem unit 54 outputs the demodulated signal to the baseband processing unit 56. The modem unit 54 may include an adaptive equalizer. The modem unit 54 performs modulation as transmission processing. The modem unit 54 outputs the modulated signal to the RF unit 52.

  The baseband processing unit 56 performs multiplexing for the plurality of terminal devices 12. The baseband processing unit 56 specifies the transmission destination of the signal demodulated by the modem unit 34 as reception processing, and outputs the specified signal to the IF unit 68. Further, the baseband processing unit 56 outputs the received signal to the modem unit 54 while associating any one of the plurality of terminal devices 12 as a transmission destination of the signal received from the IF unit 68. Further, the base station apparatus 10 is connected to the network 72 via the IF unit 68.

  The acquisition unit 58 receives packet signals from each of the plurality of terminal devices 12 via the base station antenna 50, the modem unit 54, and the baseband processing unit 56. Furthermore, the acquisition unit 58 acquires the position coordinates, the SNR and the delay spread as information relating to the communication state, from the received packet signal. Since these pieces of information are as described above, the description thereof is omitted. The acquisition unit 58 outputs the acquired information to the storage unit 60 while associating the terminal device 12 that has transmitted the information.

  The storage unit 60 stores the SNR, delay spread, and position coordinates from the acquisition unit 58. FIG. 5 shows the structure of data stored in the storage unit 60. As illustrated, SNR, delay spread, and position coordinates are stored so as to be associated with each of the first terminal device 12a to the fourth terminal device 12d. Here, the SNR corresponding to each of the first terminal device 12a to the fourth terminal device 12d is expressed as “A1” to “A4”, and these correspond to arbitrary values. The storage unit 60 updates the stored data at the timing when the acquisition unit 58 acquires the SNR and the like.

  Returning to FIG. Based on the SNR and delay spread acquired by the acquisition unit 58 and stored in the storage unit 60, the selection unit 62 satisfies a predetermined condition rather than the SNR and delay spread of any of the plurality of terminal devices 12. The terminal device 12 having a close SNR and delay spread is selected. Here, any one of the plurality of terminal devices 12 corresponds to the terminal device 12 to be processed, and corresponds to the first terminal device 12a in FIG. The predetermined conditions are also as described above, but will be described in more detail here. The selection unit 62 defines a principle condition and an exception condition as predetermined conditions. The selection unit 62 performs selection based on the principle condition, and further performs selection based on an exceptional condition when a plurality of terminal devices 12 are selected.

  As a general condition, the selection unit 62 defines that the SNR is larger than the SNR of the terminal device 12 to be processed and the delay spread is smaller than the delay spread of the terminal device 12 to be processed. Therefore, the selection unit 62 selects the terminal device 12 having an SNR larger than the SNR in the processing target terminal device 12 and having a delay spread smaller than the delay spread in the processing target terminal device 12. That is, the principle condition defines a relative condition for the plurality of terminal devices 12.

  Under the exception conditions, the selector 62 sets threshold values for the SNR and delay spread (hereinafter, the threshold for the SNR is referred to as “SNR threshold”, and the threshold for the delay spread is “delay spread”). (Referred to as "threshold value"). The exception condition stipulates that among the plurality of terminal apparatuses 12 that satisfy the principle condition, the terminal apparatus 12 has an SNR larger than the SNR threshold and a delay spread smaller than the delay spread threshold. Therefore, the selection unit 62 has a SNR larger than the SNR threshold and a delay spread smaller than the delay spread threshold among the plurality of terminal devices 12 satisfying the principle condition. Select with priority. That is, the exception condition defines an absolute condition.

  If there are a plurality of terminal devices 12 that satisfy the two thresholds, the selection unit 62 selects the terminal device 12 with the highest SNR among them. Furthermore, if any of the plurality of terminal devices 12 that satisfy the principle condition does not satisfy the two threshold values, the selection unit 62 selects the terminal device 12 that satisfies any one of the threshold values. The former is given priority to the terminal device 12 that satisfies only the SNR threshold and the terminal device 12 that satisfies only the delay spread threshold.

  The deriving unit 64 acquires the coordinates of the position of the processing target terminal device 12 from the storage unit 60. In addition, the derivation unit 64 acquires the coordinates of the position of the terminal device 12 selected by the selection unit 62 from the storage unit 60. Based on the coordinates of the position of the terminal device 12 to be processed and the coordinates of the position of the selected terminal device 12, the deriving unit 64 determines the direction to the selected terminal device 12 with respect to the terminal device 12 to be processed. To derive. Here, an orthogonal coordinate system composed of an x-axis and a y-axis is defined, and the terminal device to be processed is determined from the coordinates of the position of the selected terminal device 12 while assigning longitude to the x-axis and assigning latitude to the y-axis. The vector of 12 coordinates is subtracted. Furthermore, the direction is derived by calculating the arc tangent of the resulting vector.

  It is assumed that the phase derived by the arc tangent is associated with the direction in advance. For example, “0 °” is associated with “east”, “90 °” is associated with “north”, “180 °” is associated with “west”, and “270 °” is associated with “south”. Assume that it is associated. Furthermore, the derivation unit 64 also calculates a distance between the coordinates of the position of the terminal device 12 to be processed and the coordinates of the position of the selected terminal device 12. This is obtained by calculating the norm from the result of the vector subtraction described above.

  The notification unit 66 generates a packet signal including the direction and distance derived by the deriving unit 64. The notification unit 66 causes the terminal device 12 to be processed to transmit the generated packet signal via the baseband processing unit 56, the modem unit 54, the RF unit 52, and the base station antenna 50. The control unit 70 controls timing and the like in the base station device 10 and executes multiplexing of the terminal devices 12. In the above description, the terminal device 12 to be processed by the selection unit 62 may be the terminal device 12 that requests the base station device 10 to start communication. In this case, the above processing is executed at the timing of starting communication. Further, the above processing may be appropriately executed even during communication.

  The operation of the communication system 100 configured as above will be described. FIG. 6 is a sequence diagram illustrating a communication procedure in the communication system 100. Here, it is assumed that the first terminal device 12a requests connection to the base station device 10, and the terminal devices 12 other than the first terminal device 12a are omitted from the description. The first terminal apparatus 12a transmits a connection request to the base station apparatus 10 (S10). The base station apparatus 10 transmits a response to the first terminal apparatus 12a (S12). Furthermore, the base station apparatus 10 transmits a packet signal to the first terminal apparatus 12a (S14). The first terminal apparatus 12a measures the SNR for the received packet signal and calculates the delay spread (S16). Further, the first terminal device 12a measures the coordinates of the position by GPS (S18). The first terminal apparatus 12a transmits a packet signal including SNR, delay spread, and position coordinates (S20).

  The base station apparatus 10 receives in advance the SNR, delay spread, and position coordinates for a plurality of terminal apparatuses 12. The base station apparatus 10 selects a terminal apparatus 12 having a larger SNR and a smaller delay spread than the first terminal apparatus 12a from among the plurality of terminal apparatuses 12 (S22). The base station apparatus 10 acquires the coordinates of the position with respect to the selected terminal apparatus 12 (S24). The base station apparatus 10 calculates the direction to the selected terminal apparatus 12 with respect to the first terminal apparatus 12a and the distance between the first terminal apparatus 12a and the selected terminal apparatus 12 (S26). The base station apparatus 10 includes the calculated direction and distance in the packet signal, and transmits the packet signal to the first terminal apparatus 12a (S28). The first terminal apparatus 12a displays the direction and distance (S30).

  FIG. 7 is a flowchart showing a communication procedure in the first terminal apparatus 12a. The modem unit 34 receives the packet signal from the base station apparatus 10 (S50). The deriving unit 38 measures the SNR for the received packet signal (S52). The deriving unit 38 calculates a delay spread for the received packet signal (S54). The GPS processing unit 28 measures the coordinates of the position (S56). The notification unit 42 transmits a packet signal including the SNR, delay spread, and position coordinates to the base station apparatus 10 (S58). If the reception unit 44 receives a packet signal including direction and distance information from the base station device 10 (Y in S60), the instruction unit 46 causes the display unit 24 to display the direction and distance (S62). . On the other hand, if the reception unit 44 does not receive a packet signal including direction and distance information from the base station apparatus 10 (N in S60), the process ends.

  FIG. 8 is a flowchart showing a communication procedure in the base station apparatus 10. The acquisition unit 58 acquires SNR, delay spread, and position coordinates from the plurality of terminal devices 12 (S80). The storage unit 60 stores SNR, delay spread, and position coordinates. The selection unit 62 refers to the storage unit 60 and searches for a terminal device 12 having a larger SNR and a smaller delay spread than the terminal device 12 to be processed among the plurality of terminal devices 12. If it exists (Y of S82), the selection part 62 will select the terminal device 12 (S84). The deriving unit 64 acquires the coordinates of the position with respect to the selected terminal device 12 (S86). The deriving unit 64 calculates the direction to the selected terminal device 12 with respect to the terminal device 12 to be processed and the distance between the terminal device 12 to be processed and the selected terminal device 12 (S88). The notification unit 66 includes the calculated direction and distance in the packet signal, and notifies the processing target terminal device 12 of the packet signal (S90). On the other hand, if it does not exist (N in S82), the process is terminated.

  According to the embodiment of the present invention, the base station apparatus notifies the terminal apparatus to be processed of the direction to the terminal apparatus that has a larger SNR and a smaller delay spread than the terminal apparatus. The terminal device to be processed can be notified of a direction in which the SNR increases and the delay spread decreases. In addition, since a terminal device having a large SNR and a small delay spread is selected from a plurality of terminal devices that are actually communicating, the direction in which the SNR is large and the delay spread is small is selected. It can be accurately identified. In addition, since the direction can be calculated based on the data received from the terminal device, an increase in processing can be suppressed. Further, by increasing the number of terminal devices to be communicated, it is possible to accurately specify the position where the SNR increases and the delay spread decreases. In addition, since the position is measured by GPS, an accurate position can be acquired. Also, since the SNR, delay spread, and position coordinates are updated, it is possible to follow changes in the radio propagation environment.

  Further, since the SNR is also notified to the terminal device to be processed such that the SNR is larger than that of the terminal device and the delay spread is small, the SNR is increased to the terminal device to be processed. In addition, the distance that the delay spread becomes small can be notified. Further, from the timing of starting communication, it is possible to instruct the user of the terminal device where the SNR is large and the delay spread is small. In addition, since the terminal device displays the direction to the terminal device that is received from the base station device, has a large SNR, and a small delay spread, the user of the terminal device satisfies a predetermined condition. You can indicate the direction of approach. In addition, if the terminal device includes an adaptive equalizer, the SNR and delay spread may be measured. In such a case, it is only necessary to add a function for measuring the position by GPS, and the scale of the device. Can be suppressed.

  In the above, this invention was demonstrated based on the Example. This embodiment is an exemplification, and it will be understood by those skilled in the art that various modifications can be made to the combination of each component and each processing process, and such modifications are also within the scope of the present invention. .

  In the embodiment of the present invention, the acquisition unit 58 acquires SNR and delay spread as information related to the communication state. However, the present invention is not limited to this, and may be one of these, for example. Other signal strengths, interference powers, and bit error rates may be used. Further, when the communication system 100 supports a variable transmission rate, the selected transmission rate may be used. That is, when the communication quality is improved, a high-speed transmission rate is selected. Moreover, these combinations may be sufficient. Further, in response to these cases, the selection unit 62 defines a predetermined condition. According to this modification, a communication state suitable for a radio propagation environment to which the communication system 100 is applied can be used. That is, any index that affects communication quality may be used.

  In the embodiment of the present invention, the derivation unit 38 of the terminal device 12 measures the communication state. However, the present invention is not limited to this. For example, the base station device 10 may include the deriving unit 38, and the deriving unit 38 may measure the communication state. In the embodiment, the state of downlink communication is measured, whereas in the modification, the state of uplink communication is measured. According to this modification, the processing of the terminal device 12 can be simplified. That is, it is only necessary to know the communication quality at the terminal device 12.

  In the embodiment of the present invention, the derivation unit 64 of the base station apparatus 10 derives the direction and distance. However, the present invention is not limited to this. For example, the terminal device 12 may include the deriving unit 64 so that the terminal device 12 derives the direction and distance. In this case, the base station device 10 transmits the coordinates of the position of the selected terminal device 12 to the terminal device 12. That is, in the base station apparatus, the acquisition unit 58 acquires information regarding the communication state for each of the plurality of terminal apparatuses 12 and position information for each of the plurality of terminal apparatuses 12. Based on the information on the communication state acquired by the acquisition unit 58 and stored in the storage unit 60, the selection unit 62 has a communication state closer to a predetermined condition than the communication state in the terminal device 12 to be processed. The terminal device 12 is selected. The selection unit 62 notifies the coordinates of the position corresponding to the terminal device 12 selected by the selection unit 62 to the plurality of terminal devices 12 to be processed. According to this modification, since the coordinates of the position of the terminal device closer to the predetermined condition than the terminal device are notified to the processing target terminal device, the processing target terminal device is close to the predetermined condition. Such coordinates of the position can be notified, and a position close to a predetermined condition can be instructed to the user of the terminal device.

  In the terminal device corresponding to the above base station apparatus, the RF unit 32 derives the state of communication with the base station apparatus 10. The acquisition unit 40 acquires the current position of the terminal device 12. The notification unit 42 notifies the base station apparatus 10 of the communication state and the current position. The reception unit 44 is a position derived in the base station apparatus 10 and a terminal apparatus whose communication state is close to a predetermined condition among a plurality of terminal apparatuses 12 communicating with the base station apparatus 10 12 positions are received from the base station apparatus 10. The deriving unit 64 calculates the direction to the position received by the receiving unit 44 with respect to the position acquired by the acquiring unit 40. The instruction unit 46 instructs the display unit 24 to display the direction calculated by the derivation unit 64. According to this modification, the direction that is close to the predetermined condition is derived and displayed with respect to the position of the terminal device that is received from the base station apparatus and close to the predetermined condition. , It is possible to instruct the user of the terminal device in a direction close to a predetermined condition. That is, it suffices if it is finally possible to instruct the user in a direction close to a predetermined condition.

  In the embodiment of the present invention, the acquisition unit 40 acquires the coordinates of the position measured by GPS from the GPS processing unit 28. However, the present invention is not limited to this. For example, the acquisition unit 40 may calculate the position coordinates based on the signals received from the plurality of base station apparatuses 10 according to the principle of three-point measurement as in the case of GPS. In this case, not the absolute latitude and longitude, but coordinates with a predetermined position as the origin may be defined. Moreover, the base station apparatus 10 may recognize its own position. The position in that case may be an absolute position or a relative position. According to this modification, the position can be measured without adding a GPS function. That is, it is only necessary that the position of the terminal device 12 can be acquired.

It is a figure which shows the structure of the communication system which concerns on the Example of this invention. It is a figure which shows the structure of the 1st terminal device of FIG. It is a figure which shows the display content in the display part of FIG. It is a figure which shows the structure of the base station apparatus of FIG. It is a figure which shows the structure of the data memorize | stored in the memory | storage part of FIG. It is a sequence diagram which shows the communication procedure in the communication system of FIG. It is a flowchart which shows the communication procedure in the 1st terminal device of FIG. It is a flowchart which shows the communication procedure in the base station apparatus of FIG.

Explanation of symbols

  10 base station device, 12 terminal device, 20 antenna for terminal, 22 radio unit, 24 display unit, 26 GPS antenna, 28 GPS processing unit, 30 control unit, 32 RF unit, 34 modem unit, 36 baseband processing unit, 38 Derivation unit, 40 acquisition unit, 42 notification unit, 44 reception unit, 46 instruction unit, 50 base station antenna, 52 RF unit, 54 modem unit, 56 baseband processing unit, 58 acquisition unit, 60 storage unit, 62 selection Unit, 64 derivation unit, 66 notification unit, 68 IF unit, 70 control unit, 72 network, 100 communication system.

Claims (7)

A communication unit that communicates with each of a plurality of terminal devices;
An acquisition unit that acquires information on a communication state for each of the plurality of terminal devices and position information for each of the plurality of terminal devices;
A selection unit that selects a terminal device in a communication state closer to a predetermined condition than a communication state in any of the plurality of terminal devices based on information on the communication state acquired in the acquisition unit;
A notification unit for notifying one of the plurality of terminal devices of the position information corresponding to the terminal device selected by the selection unit via the communication unit;
A base station apparatus comprising: A communication unit that communicates with each of a plurality of terminal devices;
An acquisition unit that acquires information on a communication state for each of the plurality of terminal devices and position information for each of the plurality of terminal devices;
A selection unit that selects a terminal device in a communication state closer to a predetermined condition than a communication state in any of the plurality of terminal devices based on information on the communication state acquired in the acquisition unit;
A deriving unit for deriving a direction to the terminal device selected by the selection unit with respect to any of the plurality of terminal devices based on the position information acquired by the acquisition unit;
A notification unit for notifying the direction derived in the deriving unit to any of the plurality of terminal devices via the communication unit;
A base station apparatus comprising: The derivation unit derives a distance between any of the plurality of terminal devices and the terminal device selected by the selection unit based on the position information acquired by the acquisition unit,
The base station apparatus according to claim 2, wherein the notification unit also notifies any one of the plurality of terminal devices of the distance derived by the deriving unit.   4. The base station apparatus according to claim 1, wherein one of the plurality of terminal devices in the selection unit is a terminal device that requests the communication unit to start communication. 5. . A terminal device that communicates with a base station device,
A deriving unit for deriving the state of communication with the base station device;
An acquisition unit for acquiring the current position of the terminal device;
A notification unit for notifying the base station apparatus of a communication state and a current position;
The position of the terminal device which is a position derived in the base station apparatus and whose communication state is close to a predetermined condition among a plurality of terminal apparatuses communicating with the base station apparatus is the base station. A reception unit to receive from the device;
A calculation unit that calculates a direction to the position received in the reception unit with respect to the position acquired in the acquisition unit;
An instruction unit for instructing a display device to display the direction calculated in the calculation unit;
A terminal device comprising: A terminal device that communicates with a base station device,
A deriving unit for deriving the state of communication with the base station device;
An acquisition unit for acquiring the current position of the terminal device;
A notification unit for notifying the base station apparatus of a communication state and a current position;
The direction derived from the base station apparatus and the direction to the position of the terminal apparatus whose communication state is close to a predetermined condition among a plurality of terminal apparatuses communicating with the base station apparatus. A reception unit that receives from the base station device;
An instruction unit for instructing a display device to display the direction received in the reception unit;
A terminal device comprising: Based on the communication status of each of the plurality of terminal devices communicating with the base station device, a terminal device having a communication state closer to a predetermined condition than the communication state of any of the plurality of terminal devices is selected. And
Based on the position information corresponding to one of the plurality of terminal devices and the position information of the selected terminal device, the direction to the selected terminal device with respect to any of the plurality of terminal devices Is derived,
A communication method, comprising: outputting a derived direction in any of the plurality of terminal devices.

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