Abstract:
Disclosed is a wireless terminal device that can display the communication quality according to the service content with reception of service provided using multiple different communication formats. In the device, a first reception field strength detector ( 101 ) detects the reception field strength with communication in a first communication format. A second reception field strength detector ( 102 ) detects the reception field strength with communication in a second communication format. A wireless status coordination unit ( 103 ) determines the reception field strength with reception of service provided with communication in the first communication format and the second communication format on the basis of the various reception field strengths detected by the first reception field strength detector ( 101 ) and the second reception field strength detector ( 102 ). A display ( 105 ) displays the reception field strength determined by the wireless status coordination unit ( 103 ).

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a radio terminal apparatus and communication quality display method, and more particularly to a radio terminal apparatus and communication quality display method that receive service provision using a plurality of different communication methods. 
       BACKGROUND ART 
       [0002]    In recent years, a portable terminal has been known that can receive provision of a desired service by using a plurality of different communication methods simultaneously. For example, a service whereby program content is received by broadcasting and participation in a vote or chat related to that program content is implemented by means of communication, or a service whereby viewing rights for that program content are obtained by means of communication, can be conceived of as services in which broadcasting and communication are linked. 
         [0003]    With a service of this kind, if provision of the service is limited to a user who is viewing content, or if it is necessary to periodically confirm viewing rights for viewed content, service provision cannot be received if a signal cannot be received with predetermined quality in all the different communication methods. 
         [0004]    Therefore, conventionally, a user confirms the radio status of the plurality of different communication methods individually, and determines whether or not service use is possible based on the confirmed individual radio statuses. In this case, even if the radio status of one or some of the communication methods is good, a state in which service is suddenly unable to be received will arise if the radio status of another communication method is poor. Also, if, in addition to the above-described service, a user is also able to use a service provided by means of communication using a single communication method, the user must determine whether or not a service whose provision is to be received henceforth is a service for which the radio statuses of a plurality of communication methods must be confirmed. 
         [0005]    The methods disclosed in Patent Literature 1 and Patent Literature 2 are known as methods of solving such problems. In Patent Literature 1, two or more graphics are created that correspond to the respective conditions of each of two or more mobile communication networks, the two or more created graphics are combined, and a graphic obtained as a result of this combining is incorporated in an image for posting as a specific graphic according to the standby state of a communication terminal apparatus. In Patent Literature 1, a specific graphic has a form in which graphics corresponding to the conditions of each mobile communication network mutually overlap in such a way that parts whose forms are equal coincide. Also, in a specific graphic, overlapping parts are displayed in a color that combines colors specific to each mobile communication network. 
         [0006]    In Patent Literature 2, for each received signal detected by a PHS reception circuit and a PDC reception circuit respectively, a color corresponding to the field strength of the received signal is read from a data table stored in memory beforehand, and a combination color is created by combining those read colors, and is displayed. In Patent Literature 2, when a displayed combination color comprises only a green component, this means that PDC communication is out of service (that is, out of range), when a displayed combination color comprises only a red component, this means that PHS communication is out of service, and when a displayed combination color is black, this means that both PHS communication and PDC communication are out of service. 
       CITATION LIST 
     Patent Literature 
     PTL 1 
     Japanese Patent Application Laid-Open No. 2002-10351 
     PTL 2 
     Japanese Patent Application Laid-Open No. 2002-353826 
     SUMMARY OF INVENTION 
     Technical Problem 
       [0007]    However, in Patent Literature 1 and Patent Literature 2, there is an either-or choice between communication methods used, and therefore a displayed combination color is simply the result of combining colors corresponding to the reception field strengths of the communication methods, and does no more than indicate the reception field strength of each communication method. Therefore, a problem with Patent Literature 1 and Patent Literature 2 is that it is only possible to confirm usable communication methods individually, and therefore communication quality corresponding to service contents cannot be displayed when provision of a desired service is received using different communication methods simultaneously. 
         [0008]    It is therefore an object of the present invention to provide a radio terminal apparatus and communication quality display method that can display communication quality corresponding to service contents when service provision is received using a plurality of different communication methods. 
       Solution to Problem 
       [0009]    A radio terminal apparatus of the present invention employs a configuration having: a detection section that, when service provision is received by performing communication by means of a plurality of different communication methods, detects communication quality individually when communication is performed by each communication method; a determination section that determines communication quality when the service provision is received, based on each detected communication quality; and a display section that displays the determined communication quality. 
         [0010]    A communication quality display method of the present invention is a communication quality display method in a radio terminal apparatus that receives service provision by performing communication by means of a plurality of different communication methods, and has the steps of: detecting communication quality individually when communication is performed by each communication method; determining communication quality when the service provision is received, based on each detected communication quality; and displaying the determined communication quality. 
       Advantageous Effects of Invention 
       [0011]    The present invention can display communication quality corresponding to service contents when service provision is received using a plurality of different communication methods. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0012]      FIG. 1  is a block diagram showing the configuration of a radio terminal apparatus according to Embodiment 1 of the present invention; 
           [0013]      FIG. 2  is a flowchart showing the operation of a radio terminal apparatus according to Embodiment 1 of the present invention; 
           [0014]      FIG. 3  is a drawing showing the relationship between the position of a radio terminal apparatus and various communication areas according to Embodiment 1 of the present invention; 
           [0015]      FIG. 4  is a drawing showing reception field strength detection results of a first reception field strength detection section and second reception field strength detection section, an adjustment result of a radio status adjustment section, and display on a display section, at various positions of a radio terminal apparatus according to Embodiment 1 of the present invention; 
           [0016]      FIG. 5  is a drawing showing an example of detection results of a first reception field strength detection section and detection results of a second reception field strength detection section at various positions according to Embodiment 1 of the present invention; 
           [0017]      FIG. 6  is a block diagram showing the configuration of a radio terminal apparatus according to Embodiment 2 of the present invention; 
           [0018]      FIG. 7  is a drawing showing an out of service determination table according to Embodiment 2 of the present invention; 
           [0019]      FIG. 8  is a drawing showing an adjustment value calculation table according to Embodiment 2 of the present invention; 
           [0020]      FIG. 9  is a flowchart showing the operation of a radio terminal apparatus according to Embodiment 2 of the present invention; 
           [0021]      FIG. 10  is a block diagram showing the configuration of a radio terminal apparatus according to Embodiment 3 of the present invention; 
           [0022]      FIG. 11  is a block diagram showing the configuration of a radio terminal apparatus according to Embodiment 4 of the present invention; and 
           [0023]      FIG. 12  is a block diagram showing the configuration of a radio terminal apparatus according to Embodiment 5 of the present invention. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0024]    Now, embodiments of the present invention will be described in detail with reference to the accompanying drawings. 
       Embodiment 1 
       [0025]      FIG. 1  is a block diagram showing the configuration of radio terminal apparatus  100  according to Embodiment 1 of the present invention. 
         [0026]    First reception field strength detection section  101  has a first-communication-method received signal received by an antenna (not shown) as input, and detects the reception field strength (RSSI: Received Signal Strength Indicator) of the input first-communication-method received signal. Then first reception field strength detection section  101  outputs the detected reception field strength to radio status adjustment section  103  as a detection result, or outputs a number of antenna bars corresponding to the detected reception field strength to radio status adjustment section  103  as a detection result. Here, the first communication method is, for example, a cellular method, PHS (Personal Handy-phone System) method, Bluetooth, wireless LAN, WiMAX (Worldwide Interoperability for Microwave Access), digital broadcasting, or the like. 
         [0027]    Second reception field strength detection section  102  has a second-communication-method received signal received by an antenna (not shown) as input, and detects the reception field strength of the input second-communication-method received signal. Then second reception field strength detection section  102  outputs the detected reception field strength to radio status adjustment section  103  as a detection result, or outputs a number of antenna bars corresponding to the detected reception field strength to radio status adjustment section  103  as a detection result. Here, the second communication method is, for example, a cellular method, PHS method, Bluetooth, wireless LAN, WiMAX, digital broadcasting, or the like. However, the second communication method is different from the first communication method, with, for example, a wireless LAN being used as the first communication method and a cellular method being used as the second communication method. 
         [0028]    Based on the reception field strength detection result input from first reception field strength detection section  101  and the reception field strength detection result input from second reception field strength detection section  102 , radio status adjustment section  103  determines the reception field strength when service is received using both the first communication method and the second communication method. At this time, radio status adjustment section  103  determines the number of bars in an antenna bar display on display section  105  as the reception field strength. Then radio status adjustment section  103  outputs the determined reception field strength to display control section  104 . Provision may also be made for radio status adjustment section  103  to output the reception field strength determined this time to display control section  104  only if the reception field strength determined this time is different from the reception field strength determined the previous time. The reception field strength determination method used by radio status adjustment section  103  will be described later herein. 
         [0029]    Display control section  104  performs display processing for displaying the reception field strength input from radio status adjustment section  103 , and performs control to display the reception field strength on display section  105 . 
         [0030]    Display section  105  is, for example, a liquid crystal display (LCD), and displays the reception field strength under the control of display control section  104 . 
         [0031]    Next, the operation of radio terminal apparatus  100  will be described using  FIG. 2 .  FIG. 2  is a flowchart showing the operation of radio terminal apparatus  100 . In  FIG. 2 , a case is shown by way of example in which first reception field strength detection section  101  and second reception field strength detection section  102  output a number of antenna bars corresponding to a detected reception field strength to radio status adjustment section  103  as a reception field strength detection result. 
         [0032]    Radio status adjustment section  103  determines whether or not reception field strength detection result Rb input from first reception field strength detection section  101 , or reception field strength detection result Rc input from second reception field strength detection section  102 , is at an out of service level (Rc=out of service or Rb=out of service?) (step ST  201 ). 
         [0033]    If reception field strength detection result Rb input from first reception field strength detection section  101  or reception field strength detection result Rc input from second reception field strength detection section  102  is at an out of service level (step ST  201 : Yes), radio status adjustment section  103  determines that reception field strength when service is received is to be displayed as out of service (Ra=out of service) (step ST  202 ). In  FIG. 2 , Ra is the reception field strength output from radio status adjustment section  103 . 
         [0034]    On the other hand, if reception field strength detection result Rb input from first reception field strength detection section  101  or reception field strength detection result Rc input from second reception field strength detection section  102  is not at an out of service level (step ST  201 : No), radio status adjustment section  103  determines whether or not the reception field strength detection result input from second reception field strength detection section  102  is smaller than an adjustment threshold value (Rc&lt;adjustment threshold value?). Furthermore, radio status adjustment section  103  determines whether or not, when 1 is subtracted from the reception field strength detection result input from first reception field strength detection section  101  (Rb−1), the subtraction result is not 0 ((Rb−1)≠out of service?) (step ST  203 ). This determination means determining whether or not the adjusted result is not out of service. 
         [0035]    If the reception field strength detection result input from second reception field strength detection section  102  is smaller than the adjustment threshold value, and when 1 is subtracted from the reception field strength detection result input from first reception field strength detection section  101  the subtraction result is not 0 (step ST  203 : Yes), radio status adjustment section  103  makes the first reception field strength detection section  101  reception field strength detection result smaller by a predetermined amount (Ra=AD(Rb)) (step ST  204 ). That is to say, radio status adjustment section  103  lowers the first reception field strength detection section  101  reception field strength detection result by 1 level. In  FIG. 2 , AD(Rb) is an adjustment function for adjusting a reception field strength detection result, and in this embodiment is a function that lowers a reception field strength detection result by 1 level. 
         [0036]    On the other hand, if the reception field strength detection result input from second reception field strength detection section  102  is not smaller than the adjustment threshold value, or if the subtraction result is 0 when 1 is subtracted from the reception field strength detection result input from first reception field strength detection section  101  (step ST  203 : No), radio status adjustment section  103  does not perform adjustment of the first reception field strength detection section  101  reception field strength detection result (Ra=Rb) (step ST  205 ). That is to say, radio status adjustment section  103  outputs the first reception field strength detection section  101  reception field strength detection result as is. 
         [0037]    In  FIG. 2 , if a volume of data transmitted using the first communication method is greater than a volume of data transmitted using the second communication method, the first reception field strength of the first communication method can be adjusted using the second reception field strength of the second communication method. Therefore, in this case, a reception field strength adjusted on the basis of the first reception field strength of the first communication method with the largest data capacity can be displayed as the reception field strength when service provision is received. 
         [0038]      FIG. 3  is a drawing showing the relationship between the position of radio terminal apparatus  100  and various communication areas;  FIG. 4  is a drawing showing reception field strength detection results of first reception field strength detection section  101  and second reception field strength detection section  102 , an adjustment result of radio status adjustment section  103 , and display on display section  105 , at positions A through G in  FIG. 3 ; and  FIG. 5  is a drawing showing an example of first reception field strength detection section  101  detection results and second reception field strength detection section  102  detection results at positions A through G in  FIG. 3 . 
         [0039]    In  FIG. 3 , position A is within second-communication-method communication area # 302 , but outside first-communication-method communication area # 301 . Also, position G is outside second-communication-method communication area # 302 , but within first-communication-method communication area # 301 . Furthermore, positions B through F are within both first-communication-method communication area # 301  and second-communication-method communication area # 302 . Consequently, positions B through F are in an area in which service use is possible. In  FIG. 4 , antenna bars are displayed by means of graphics ( FIG. 4(C)  through  FIG. 4(F) ) combining an antenna and bars. The number of bars changes according to the reception field strength. 
         [0040]    As shown in  FIG. 5 , when radio terminal apparatus  100  performs communication at position A, first reception field strength detection section  101  detection result Rb_ex(t) is smaller than out-of-service threshold value # 501 . Therefore, as shown in  FIG. 4(A) , first reception field strength detection section  101  detects “out of service” as a reception field strength detection result, and second reception field strength detection section  102  detects level  3  as a reception field strength detection result. As a result, radio status adjustment section  103  determines that the reception field strength when service is received is to be made “out of service”, and display section  105  provides an “out of service” display. 
         [0041]    Also, as shown in  FIG. 5 , when radio terminal apparatus  100  performs communication at position B, first reception field strength detection section  101  detection result Rb_ex(t) is smaller than within-range level  0  and  1  threshold value # 502  and greater than or equal to out-of-service threshold value # 501 . Therefore, as shown in  FIG. 4(B) , first reception field strength detection section  101  detects level  0  as a reception field strength detection result, and second reception field strength detection section  102  detects level  3  as a reception field strength detection result. As a result, radio status adjustment section  103  determines that the reception field strength when service is received is to be made level  0 , and display section  105  provides an antenna bar display indicating level  0 . 
         [0042]    Also, as shown in  FIG. 5 , when radio terminal apparatus  100  performs communication at position C, first reception field strength detection section  101  detection result Rb_ex(t) is smaller than within-range level  1  and  2  threshold value # 503  and greater than or equal to within-range level  0  and  1  threshold value # 502 . Therefore, as shown in  FIG. 4(C) , first reception field strength detection section  101  detects level  1  as a reception field strength detection result, and second reception field strength detection section  102  detects level  3  as a reception field strength detection result. As a result, radio status adjustment section  103  determines that the reception field strength when service is received is to be made level  1 , and display section  105  provides an antenna bar display indicating level  1 . 
         [0043]    Also, as shown in  FIG. 5 , when radio terminal apparatus  100  performs communication at position D, first reception field strength detection section  101  detection result Rb_ex(t) is smaller than within-range level  2  and  3  threshold value # 504  and greater than or equal to within-range level  1  and  2  threshold value # 503 . Therefore, as shown in  FIG. 4(D) , first reception field strength detection section  101  detects level  2  as a reception field strength detection result, and second reception field strength detection section  102  detects level  3  as a reception field strength detection result. As a result, radio status adjustment section  103  determines that the reception field strength when service is received is to be made level  2 , and display section  105  provides an antenna bar display indicating level  2 . 
         [0044]    Also, as shown in  FIG. 5 , when radio terminal apparatus  100  performs communication at position E, first reception field strength detection section  101  detection result Rb_ex(t) is greater than or equal to within-range level  2  and  3  threshold value # 504 , and second reception field strength detection section  102  detection result Rc_ex(t) is greater than or equal to adjustment threshold value # 505 . Therefore, as shown in  FIG. 4(E) , first reception field strength detection section  101  detects level  3  as a reception field strength detection result, and second reception field strength detection section  102  detects level  3  as a reception field strength detection result. As a result, radio status adjustment section  103  determines that the reception field strength when service is received is to be made level  3 , and display section  105  provides an antenna bar display indicating level  3 . 
         [0045]    Also, as shown in  FIG. 5 , when radio terminal apparatus  100  performs communication at position F, first reception field strength detection section  101  detection result Rb_ex(t) is greater than or equal to within-range level  2  and  3  threshold value # 504 , and second reception field strength detection section  102  detection result Rc_ex(t) is smaller than adjustment threshold value # 505  and greater than out-of-service threshold value # 506 . Therefore, as shown in  FIG. 4(F) , first reception field strength detection section  101  detects level  3  as a reception field strength detection result, and second reception field strength detection section  102  detects level  0  as a reception field strength detection result. As a result, radio status adjustment section  103  subtracts 1 from first reception field strength detection section  101  detection result Rb_ex(t)=3 (Ra=AD(Rb)=Rb−1), and determines that the reception field strength when service is received is to be made level  2 , and display section  105  provides an antenna bar display indicating level  2 . 
         [0046]    Also, as shown in  FIG. 5 , when radio terminal apparatus  100  performs communication at position G, first reception field strength detection section  101  detection result Rb_ex(t) is greater than or equal to within-range level  2  and  3  threshold value # 504 , and second reception field strength detection section  102  detection result Rc_ex(t) is less than or equal to out-of-service threshold value # 506 . Therefore, as shown in  FIG. 4(G) , first reception field strength detection section  101  detects level  3  as a reception field strength detection result, and second reception field strength detection section  102  detects “out of service” as a reception field strength detection result. As a result, radio status adjustment section  103  determines that the reception field strength when service is received is to be made “out of service”, and display section  105  provides an “out of service” display. 
         [0047]    From the above, it can be seen that when radio terminal apparatus  100  moves from position F to position G, display section  105  displays a reception field strength lower than an actual first reception field strength detection section  101  reception field strength detection result. As a result, a user can confirm that there is a possibility of service ceasing to be receivable by viewing the display on display section  105 . 
         [0048]    In contrast, conventionally, an actual reception field strength detection result for a first communication method is displayed as is. For example, when a radio terminal apparatus is at position F, a level  3  antenna bar display is provided. Therefore, conventionally, when a radio terminal apparatus moves from position F to position G, an out of service state suddenly arises even though level  3  is being displayed, and service suddenly ceases to be receivable when not expected by the user. 
         [0049]    A description will now be given of the operation of radio terminal apparatus  100  when first reception field strength detection section  101  and second reception field strength detection section  102  output an actual detected reception field strength to radio status adjustment section  103  as a detection result. 
         [0050]    In this case, radio status adjustment section  103  indirectly adjusts the number of bars in an antenna bar display on display section  105  by finding a weighted average. That is to say, radio status adjustment section  103  finds a weighted average by means of equation 1. 
         [0000]        AD ( RB,Rc )=(( Wb*Rb+Wc*Rc )/( Rb+Rc ))  (Equation 1)
 
         [0051]    where: 
         [0052]    AD(RB, Rc): weighted average 
         [0053]    Wb, Wc: weighting coefficients 
         [0054]    Rb: First reception field strength detection section  101  detection result (RSSI) 
         [0055]    Rc: Second reception field strength detection section  102  detection result (RSSI) 
         [0056]    Then radio status adjustment section  103  adjusts the number of bars in the antenna bar display by comparing the weighted average found by means of above equation 1 with a threshold value. For example, if the weighted average is less than or equal to the threshold value, radio status adjustment section  103  determines that the number of bars in the antenna bar display determined using a reception field strength detected by first reception field strength detection section  101  is to be decreased by 1. Other operations of radio terminal apparatus  100  are as shown in  FIG. 2  through  FIG. 5 , and therefore a description thereof is omitted here. 
         [0057]    Thus, according to this embodiment, reception field strength corresponding to service contents can be displayed when service provision is received using a plurality of communication methods. Also, according to this embodiment, by adjusting reception field strength according to individual transmission capacities in a plurality of communication methods, reception field strength adjusted on the basis of a communication method for which good quality is required, such as a communication method in which a large volume of data is transmitted, can be displayed as the reception field strength when service provision is received. 
       Embodiment 2 
       [0058]      FIG. 6  is a block diagram showing the configuration of radio terminal apparatus  600  according to Embodiment 2 of the present invention. 
         [0059]    As compared with radio terminal apparatus  100  according to Embodiment 1 shown in  FIG. 1 , radio terminal apparatus  600  shown in  FIG. 6  is additionally provided with out of service determination table holding section  601  and adjustment value calculation table holding section  602 , and has radio status adjustment section  603  instead of radio status adjustment section  103 . Configuration parts in  FIG. 6  identical to those in  FIG. 1  are assigned the same reference codes as in  FIG. 1 , and descriptions thereof are omitted here. 
         [0060]    Out of service determination table holding section  601  holds threshold values for determining whether or not a detected reception field strength is at an out of service level. 
         [0061]    Adjustment value calculation table holding section  602  holds threshold values for determining a reception field strength when service is received using both a first communication method and a second communication method. 
         [0062]    First reception field strength detection section  101  has a first-communication-method received signal received by an antenna (not shown) as input, and detects the reception field strength of the input first-communication-method received signal. Then first reception field strength detection section  101  outputs the detected reception field strength to radio status adjustment section  603  as a detection result, or outputs a number of antenna bars corresponding to the detected reception field strength to radio status adjustment section  603  as a detection result. 
         [0063]    Second reception field strength detection section  102  has a second-communication-method received signal received by an antenna (not shown) as input, and detects the reception field strength of the input second-communication-method received signal. Then second reception field strength detection section  102  outputs the detected reception field strength to radio status adjustment section  603  as a detection result, or outputs a number of antenna bars corresponding to the detected reception field strength to radio status adjustment section  603  as a detection result. 
         [0064]    Radio status adjustment section  603  determines the reception field strength when service is received using both the first communication method and the second communication method by comparing the reception field strength detection result input from first reception field strength detection section  101  and the reception field strength detection result input from second reception field strength detection section  102  with an out of service threshold value held in out of service determination table holding section  601  and an adjustment value held in adjustment value calculation table holding section  602 . At this time, radio status adjustment section  603  determines the number of bars in an antenna bar display on display section  105  as the reception field strength. Then radio status adjustment section  603  outputs the determined reception field strength to display control section  104 . Provision may also be made for radio status adjustment section  603  to output the reception field strength determined this time to display control section  104  only if the reception field strength determined this time is different from the reception field strength determined the previous time. The reception field strength determination method used by radio status adjustment section  603  will be described later herein. 
         [0065]    Display control section  104  performs display processing for displaying the reception field strength input from radio status adjustment section  603 , and performs control to display the reception field strength on display section  105 . 
         [0066]      FIG. 7  is a drawing showing an out of service determination table, and  FIG. 8  is a drawing showing an adjustment value calculation table. In  FIG. 8 , rcr 1 &gt;rcr 2  and AD 1 (Rb)&gt;AD 2 (Rb)&gt;AD 3 (Rb). 
         [0067]    Next, the operation of radio terminal apparatus  600  will be described using  FIG. 9 .  FIG. 9  is a flowchart showing the operation of radio terminal apparatus  600 . In  FIG. 9 , a case is shown by way of example in which first reception field strength detection section  101  and second reception field strength detection section  102  output a detected reception field strength to radio status adjustment section  603  as a detection result. 
         [0068]    Radio status adjustment section  603  determines whether or not reception field strength detection result Rb input from first reception field strength detection section  101 , or reception field strength detection result Rc input from second reception field strength detection section  102 , is smaller than out of service determination table threshold value rbo or rco respectively (Rc&lt;rco or Rb&lt;rbo?) (step ST 901 ). 
         [0069]    If reception field strength detection result Rb input from first reception field strength detection section  101  or reception field strength detection result Rc input from second reception field strength detection section  102  is smaller than out of service determination table threshold value rbo or rco respectively (step ST 901 : Yes), radio status adjustment section  603  determines that reception field strength when service is received is to be displayed as out of service (Ra=out of service) (step ST 902 ). Then display section  105  provides an “out of service” display. 
         [0070]    On the other hand, if reception field strength detection result Rb input from first reception field strength detection section  101  or reception field strength detection result Rc input from second reception field strength detection section  102  is not smaller than out of service determination table threshold value rbo or rco respectively (step ST 901 : No), radio status adjustment section  603  determines whether or not reception field strength detection result Rc input from second reception field strength detection section  102  is greater than or equal to adjustment value calculation table threshold value rcr 1  (Rc≧rcr 1 ?) (step ST 903 ). 
         [0071]    If reception field strength detection result Rc input from second reception field strength detection section  102  is greater than or equal to adjustment value calculation table threshold value rcr 1  (step ST 903 : Yes), radio status adjustment section  603  refers to the adjustment value calculation table held in adjustment value calculation table holding section  602 , and selects adjustment value AD 1 (Rb) as adjustment result Ra (Ra=AD 1 (Rb)) (step ST 904 ). Also, radio status adjustment section  603  adjusts the reception field strength to be output by means of selected adjustment value AD 1 (Rb). For example, radio status adjustment section  603  multiplies reception field strength detection result Rb input from first reception field strength detection section  101  by “adjustment value AD 1 (Rb)=1”, finds adjustment result Ra by comparing the multiplication result with a threshold value, and outputs found adjustment result Ra. Then display section  105  displays adjustment result Ra. 
         [0072]    On the other hand, if reception field strength detection result Rc input from second reception field strength detection section  102  is not greater than or equal to adjustment value calculation table threshold value rcr 1  (step ST 903 : No), radio status adjustment section  603  determines whether or not reception field strength detection result Rc input from second reception field strength detection section  102  is greater than or equal to adjustment value calculation table threshold value rcr 2  (Rc≧rcr 2 ?) (step ST 905 ). 
         [0073]    If reception field strength detection result Rc input from second reception field strength detection section  102  is greater than or equal to adjustment value calculation table threshold value rcr 2  (step ST 905 : Yes), radio status adjustment section  603  refers to the adjustment value calculation table held in adjustment value calculation table holding section  602 , and selects adjustment value AD 2 (Rb) as adjustment result Ra (Ra=AD 2 (Rb)) (step ST 906 ). Also, radio status adjustment section  603  adjusts the reception field strength to be output by means of selected adjustment value AD 2 (Rb). For example, radio status adjustment section  603  multiplies reception field strength detection result Rb input from first reception field strength detection section  101  by “adjustment value AD 2 (Rb)=0.9”, finds adjustment result Ra by comparing the multiplication result with a threshold value, and outputs found adjustment result Ra. Then display section  105  displays adjustment result Ra. 
         [0074]    On the other hand, if reception field strength detection result Rc input from second reception field strength detection section  102  is not greater than or equal to adjustment value calculation table threshold value rcr 2  (step ST 905 : No), radio status adjustment section  603  refers to the adjustment value calculation table held in adjustment value calculation table holding section  602 , and selects adjustment value AD 3 (Rb) as adjustment result Ra (Ra=AD 3 (Rb)) (step ST 907 ). Also, radio status adjustment section  603  adjusts the reception field strength to be output by means of selected adjustment value AD 3 (Rb). For example, radio status adjustment section  603  multiplies reception field strength detection result Rb input from first reception field strength detection section  101  by “adjustment value AD 3 (Rb)=0.7”, finds adjustment result Ra by comparing the multiplication result with a threshold value, and outputs found adjustment result Ra. Then display section  105  displays adjustment result Ra. 
         [0075]    In  FIG. 9 , processing in step ST 901  and step ST 902  is processing in accordance with the out of service determination table, and processing in step ST 903  through step ST 907  is processing in accordance with the adjustment value calculation table. 
         [0076]    Thus, according to this embodiment, in addition to the provision of the effects of Embodiment 1 described above, processing for determining reception field strength can be simplified since reception field strength to be displayed is determined using a threshold value held in a table. Also, according to this embodiment, a plurality of threshold values are provided for comparison with reception field strength detection result Rc input from the second reception field strength detection section, enabling reception field strength to be switched in a step-by-step manner, and enabling user caution to be prompted in a step-by-step manner. 
       Embodiment 3 
       [0077]      FIG. 10  is a block diagram showing the configuration of radio terminal apparatus  1000  according to Embodiment 3 of the present invention. 
         [0078]    As compared with radio terminal apparatus  100  according to Embodiment 1 shown in  FIG. 1 , radio terminal apparatus  1000  shown in  FIG. 10  is additionally provided with adjustment command determination section  1001 , and has radio status adjustment section  1002  instead of radio status adjustment section  103 . Configuration parts in  FIG. 10  identical to those in  FIG. 1  are assigned the same reference codes as in  FIG. 1 , and descriptions thereof are omitted here. 
         [0079]    When adjustment command determination section  1001  acquires command information commanding reception field strength adjustment, adjustment command determination section  1001  commands radio status adjustment section  1002  to adjust reception field strength. Here, command information is, for example, information indicating that a service provided by means of communication using both a first communication method and a second communication method has been selected by the user by depression of a service selection button (not shown) provided on radio terminal apparatus  1000 , information indicating that the URL of a service provider associated by means of a URL has been selected, information indicating that a service is a service provided by means of communication using both a first communication method and a second communication method held in data received by means of the first communication method or second communication method, or that a service is a service provided by means of communication using both a first communication method and a second communication method held in data further received by means of the first communication method and second communication method by selecting information (for example, a URL) held in data received by means of the first communication method or second communication method. 
         [0080]    First reception field strength detection section  101  has a first-communication-method received signal received by an antenna (not shown) as input, and detects the reception field strength of the input first-communication-method received signal. Then first reception field strength detection section  101  outputs the detected reception field strength to radio status adjustment section  1002  as a detection result, or outputs a number of antenna bars corresponding to the detected reception field strength to radio status adjustment section  1002  as a detection result. 
         [0081]    Second reception field strength detection section  102  has a second-communication-method received signal received by an antenna (not shown) as input, and detects the reception field strength of the input second-communication-method received signal. Then second reception field strength detection section  102  outputs the detected reception field strength to radio status adjustment section  1002  as a detection result, or outputs a number of antenna bars corresponding to the detected reception field strength to radio status adjustment section  1002  as a detection result. 
         [0082]    If performance of reception field strength adjustment has been commanded by adjustment command determination section  1001 , radio status adjustment section  1002  determines the reception field strength when service is received using both the first communication method and the second communication method based on the reception field strength detection result input from first reception field strength detection section  101  and the reception field strength detection result input from second reception field strength detection section  102 . At this time, radio status adjustment section  1002  determines the number of bars in an antenna bar display on display section  105  as the reception field strength. Then radio status adjustment section  1002  outputs the determined reception field strength to display control section  104 . Provision may also be made for radio status adjustment section  1002  to output the reception field strength determined this time to display control section  104  only if the reception field strength determined this time is different from the reception field strength determined the previous time. 
         [0083]    Display control section  104  performs display processing for displaying the reception field strength input from radio status adjustment section  1002 , and performs control to display the reception field strength on display section  105 . 
         [0084]    Except for the fact that reception field strength adjustment is performed when commanded by adjustment command determination section  1001 , the operation of radio terminal apparatus  1000  is as shown in  FIG. 2  through  FIG. 5 , and therefore a description thereof is omitted here. 
         [0085]    Thus, according to this embodiment, in addition to the provision of the effects of Embodiment 1 described above, reception field strength adjustment is performed only when necessary, enabling the processing load associated with reception field strength adjustment to be alleviated. Also, according to this embodiment, switching between performing or not performing reception field strength adjustment can be performed for each service provided to a user based on command information, enabling reception field strength display appropriate to a type of service to be performed. 
       Embodiment 4 
       [0086]      FIG. 11  is a block diagram showing the configuration of radio terminal apparatus  1100  according to Embodiment 4 of the present invention. 
         [0087]    As compared with radio terminal apparatus  100  according to Embodiment 1 shown in  FIG. 1 , radio terminal apparatus  1100  shown in  FIG. 11  is additionally provided with adjustment condition acquisition section  1101 , and has radio status adjustment section  1102  instead of radio status adjustment section  103 . Configuration parts in  FIG. 11  identical to those in  FIG. 1  are assigned the same reference codes as in  FIG. 1 , and descriptions thereof are omitted here. 
         [0088]    Adjustment condition acquisition section  1101  acquires adjustment parameter information. Here, adjustment parameters are, for example, threshold values # 501  through # 506  in  FIG. 5 , or information in the tables in  FIG. 7  and  FIG. 8 . 
         [0089]    First reception field strength detection section  101  has a first-communication-method received signal received by an antenna (not shown) as input, and detects the reception field strength of the input first-communication-method received signal. Then first reception field strength detection section  101  outputs the detected reception field strength to radio status adjustment section  1102  as a detection result, or outputs a number of antenna bars corresponding to the detected reception field strength to radio status adjustment section  1102  as a detection result. 
         [0090]    Second reception field strength detection section  102  has a second-communication-method received signal received by an antenna (not shown) as input, and detects the reception field strength of the input second-communication-method received signal. Then second reception field strength detection section  102  outputs the detected reception field strength to radio status adjustment section  1102  as a detection result, or outputs a number of antenna bars corresponding to the detected reception field strength to radio status adjustment section  1102  as a detection result. 
         [0091]    Radio status adjustment section  1102  determines the reception field strength when service is received using both the first communication method and the second communication method by comparing the reception field strength detection result input from first reception field strength detection section  101  and the reception field strength detection result input from second reception field strength detection section  102  with a threshold value acquired by adjustment condition acquisition section  1101 . At this time, radio status adjustment section  1102  determines the number of bars in an antenna bar display on display section  105  as the reception field strength. Then radio status adjustment section  1102  outputs the determined reception field strength to display control section  104 . Provision may also be made for radio status adjustment section  1102  to output the reception field strength determined this time to display control section  104  only if the reception field strength determined this time is different from the reception field strength determined the previous time. 
         [0092]    Display control section  104  performs display processing for displaying the reception field strength input from radio status adjustment section  1102 , and performs control to display the reception field strength on display section  105 . 
         [0093]    Except for the fact that a threshold value is set using adjustment parameter information acquired by adjustment condition acquisition section  1101 , the operation of radio terminal apparatus  1100  is as shown in  FIG. 2  through  FIG. 5 , and therefore a description thereof is omitted here. 
         [0094]    Thus, according to this embodiment, in addition to the provision of the effects of Embodiment 1 described above, it is not necessary to store a threshold value, enabling storage capacity to be reduced and the apparatus to be made smaller. Also, according to this embodiment, a different threshold value can be set when service contents are changed or when a change occurs in the time period, the communication environment, or suchlike environmental conditions, enabling reception field strength appropriate to service contents and environmental conditions to be displayed. 
         [0095]    In this embodiment, parameter information comprises threshold values # 501  through # 506  in  FIG. 5 , or information in the tables in  FIG. 7  and  FIG. 8 , but the present invention is not limited to this, and may also use parameter information for finding threshold values # 501  through # 506  in  FIG. 5 , or threshold values in the tables in  FIG. 7  and  FIG. 8 , by means of calculation. 
       Embodiment 5 
       [0096]      FIG. 12  is a block diagram showing the configuration of radio terminal apparatus  1200  according to Embodiment 5 of the present invention. 
         [0097]    As compared with radio terminal apparatus  100  according to Embodiment 1 shown in  FIG. 1 , radio terminal apparatus  1200  shown in  FIG. 12  is additionally provided with determination table holding section  1201  and determination table selection section  1202 , and has radio status adjustment section  1203  instead of radio status adjustment section  103 . Configuration parts in  FIG. 12  identical to those in  FIG. 1  are assigned the same reference codes as in  FIG. 1 , and descriptions thereof are omitted here. 
         [0098]    Determination table holding section  1201  holds a reception field strength adjustment table for each service. 
         [0099]    Determination table selection section  1202  acquires service information that is information relating to a service, and selects a determination table corresponding to the service to which the acquired service information relates from the determination tables stored in determination table holding section  1201 . Here, service information is information on transmitted data transmission capacity, transmitted data type, such as voice, image, and so forth, type of service contents, or the like. 
         [0100]    First reception field strength detection section  101  has a first-communication-method received signal received by an antenna (not shown) as input, and detects the reception field strength of the input first-communication-method received signal. Then first reception field strength detection section  101  outputs the detected reception field strength to radio status adjustment section  1203  as a detection result, or outputs a number of antenna bars corresponding to the detected reception field strength to radio status adjustment section  1203  as a detection result. 
         [0101]    Second reception field strength detection section  102  has a second-communication-method received signal received by an antenna (not shown) as input, and detects the reception field strength of the input second-communication-method received signal. Then second reception field strength detection section  102  outputs the detected reception field strength to radio status adjustment section  1203  as a detection result, or outputs a number of antenna bars corresponding to the detected reception field strength to radio status adjustment section  1203  as a detection result. 
         [0102]    Radio status adjustment section  1203  determines the reception field strength when service is received using both the first communication method and the second communication method by comparing the reception field strength detection result input from first reception field strength detection section  101  and the reception field strength detection result input from second reception field strength detection section  102  with respective threshold values held in the determination table selected by determination table selection section  1202 . At this time, radio status adjustment section  1203  determines the number of bars in an antenna bar display on display section  105  as the reception field strength. Then radio status adjustment section  1203  outputs the determined reception field strength to display control section  104 . Provision may also be made for radio status adjustment section  1203  to output the reception field strength determined this time to display control section  104  only if the reception field strength determined this time is different from the reception field strength determined the previous time. 
         [0103]    Display control section  104  performs display processing for displaying the reception field strength input from radio status adjustment section  1203 , and performs control to display the reception field strength on display section  105 . 
         [0104]    Except for the fact that a determination table is selected using service information and reception field strength is adjusted based on the selected determination table, the operation of radio terminal apparatus  1200  is as shown in  FIG. 2  through  FIG. 5 , and therefore a description thereof is omitted here. 
         [0105]    Thus, according to this embodiment, in addition to the provision of the effects of Embodiment 1 described above, reception field strength appropriate to service contents can be displayed by enabling a different threshold value to be set according to service contents. 
         [0106]    In above Embodiment 1 through Embodiment 5, a radio status adjustment section adjusts the number of bars in an antenna bar display on a display section, but the present invention is not limited to this, and any display that indicates reception field strength may be adjusted. Also, in above Embodiment 1 through Embodiment 5, service provision is received using two communication methods—a first communication method and a second communication method—but the present invention is not limited to this, and may also be applied to a case in which service provision is received using any three or more communication methods. Furthermore, in above Embodiment 1 through Embodiment 5, a case has been described in which communication quality is reception field strength, but the present invention is not limited to this, and quality may also be based on a measure such as the transmission or reception data error rate, packet loss rate, transmission delay amount, data transmission speed, field strength variation, or the like. 
         [0107]    The disclosure of Japanese Patent Application No. 2008-265320, filed on Oct. 14, 2008, including the specification, drawings and abstract, is incorporated herein by reference in its entirety. 
       INDUSTRIAL APPLICABILITY 
       [0108]    A radio terminal apparatus and communication quality display method according to the present invention are particularly suitable for receiving service provision using a plurality of different communication methods.