Receiving apparatus, transmitting apparatus and transmitting/receiving system

Abstract

A receiving apparatus is for selecting and receiving a radio signal in a frame structure having an information body part including at least information body and an additional part including information for receiving field intensity measurement by using a plurality of antennas. The apparatus includes a controller that measures a receiving field intensity of not a first antenna which has received the information body in a transmission period of the additional part in a current frame but a second antenna, and measures a receiving field intensity of the first antenna in a transmission period of the information body part in the current frame, and if the receiving field intensity of the second antenna exceeds the receiving field intensity of the first antenna, selects and changes to the second antenna as the first antenna of a next frame.

1 . A receiving apparatus for selecting and receiving a radio signal in a frame structure having an information body part including at least information body and an additional part including information for receiving field intensity measurement by using a plurality of antennas, the apparatus comprising:
 a controller that measures a receiving field intensity of not a first antenna which has received the information body in a transmission period of the additional part in a current frame but a second antenna, and measures a receiving field intensity of the first antenna in a transmission period of the information body part in the current frame, and if the receiving field intensity of the second antenna exceeds the receiving field intensity of the first antenna, selects and changes to the second antenna as the first antenna of a next frame.   
     
     
         2 . The receiving apparatus according to  claim 1 , wherein when the receiving field intensity of the second antenna does not exceed the receiving field intensity of the first antenna, the controller sequentially changes to other second antenna. 
     
     
         3 . The receiving apparatus according to  claim 1 , wherein the controller provides a timing of the receiving field intensity measurement of the second antenna near the start of the transmission period of the information body part. 
     
     
         4 . The receiving apparatus according to  claim 1 , wherein the controller measures receiving field intensities of a plurality of second antennas in the transmission period of the additional part, and when the receiving field intensity of a second antenna having the largest receiving field intensity out of the field intensities of the plurality of second antennas exceeds the receiving field intensity of the first antenna, selects and changes to the second antenna as the first antenna of a next frame. 
     
     
         5 . The receiving apparatus according to  claim 1 , comprising an antenna changeover unit that is connected to each antenna in correspondence to arrangement positions of the plurality of antennas and detects a connection state of each antenna to change over the connected antennas according to an instruction,
 wherein the controller selects and changes to an antenna whose connection is detected by the antenna changeover unit.   
     
     
         6 . A receiving apparatus for receiving a radio signal, transmitted from the inside of a subject, in a frame structure having a video signal part for transmitting at least a video signal and an additional part including information for receiving field intensity measurement by using a plurality of antennas provided outside the subject, the apparatus comprising:
 a changeover unit that selects and changes over the plurality of antennas;   a field intensity measurement unit that measures a receiving field intensity of not a first antenna which has received the radio signal in a transmission period of the additional part in a current frame but a second antenna, and measures a receiving field intensity of the first antenna in a transmission period of the video signal part in the current frame;   a selection controller that, when the receiving field intensity of the second antenna measured by the field intensity measurement unit exceeds the receiving field intensity of the first antenna, selects the second antenna as the first antenna of a next frame; and   a changeover controller that sequentially changes over and connects an antenna other than the first antenna selected by the selection controller in a transmission period of the additional part of the next frame, and changes to and connects the selected first antenna in a transmission period of the video signal part.   
     
     
         7 . A receiving apparatus for selecting and receiving a radio signal in a frame structure having an information body part including at least information body and an additional part including information for receiving field intensity measurement by using a plurality of antennas, the apparatus comprising:
 a controller that measures receiving field intensities of more than two antennas in the additional part in a current frame, and selects and changes to an antenna having the largest receiving field intensity out of the more than two antennas as an antenna for receiving the information body part in a current frame.   
     
     
         8 . The receiving apparatus according to  claim 7 , wherein the more than two antennas are all of the plurality of antennas. 
     
     
         9 . The receiving apparatus according to  claim 7 , wherein the more than two antennas are an antenna group in which the plurality of antennas are grouped. 
     
     
         10 . The receiving apparatus according to  claim 7 , wherein the more than two antennas are an antenna group near an antenna which has received the information body in a previous frame. 
     
     
         11 . The receiving apparatus according to  claim 7 , wherein the plurality of antennas each have a serial number for a moving path of a transmitting apparatus communicating with the receiving apparatus, and the more than two antennas are an antenna group of the antenna which has received the information body in a previous frame and subsequent antennas. 
     
     
         12 . The receiving apparatus according to  claim 7 , comprising an antenna changeover unit that is connected to each antenna in correspondence to arrangement positions of the plurality of antennas and detects a connection state of each antenna to change over the connected antennas according to an instruction,
 wherein the controller selects and changes to an antenna whose connection has been detected by the antenna changeover unit.   
     
     
         13 . A receiving apparatus for selecting and receiving a radio signal in a frame structure having an information body part including at least information body and an additional part including information for receiving field intensity measurement by using a plurality of antennas, the apparatus comprising:
 a controller that compares a first receiving field intensity of an antenna which has received the information body in a previous frame with a second receiving field intensity being the largest receiving field intensity out of a result of measurement of receiving field intensities of more than two antennas other than the antenna in the additional part of a current frame, and selects and changes to the antenna having the larger receiving field intensity as an antenna for receiving the information body part in the current frame.   
     
     
         14 . The receiving apparatus according to  claim 13 , wherein the more than two antennas are antennas other than the antenna having the first receiving field intensity. 
     
     
         15 . The receiving apparatus according to  claim 13 , wherein the more than two antennas are an antenna group in which the plurality of antennas are grouped. 
     
     
         16 . The receiving apparatus according to  claim 13 , wherein the more than two antennas are an antenna group near an antenna which has received the information body in a previous frame. 
     
     
         17 . The receiving apparatus according to  claim 13 , wherein the plurality of antennas each have a serial number for a moving path of a transmitting apparatus communicating with the receiving apparatus, and the more than two antennas are an antenna group of the antenna which has received the information body in a previous frame and subsequent antennas. 
     
     
         18 . The receiving apparatus according to  claim 13 , comprising an antenna changeover unit that is connected to each antenna in correspondence to arrangement positions of the plurality of antennas and detects a connection state of each antenna to change over the connected antennas according to an instruction,
 wherein the controller selects and changes to an antenna whose connection has been detected by the antenna changeover unit.   
     
     
         19 . A receiving apparatus for selecting and receiving a radio signal in a frame structure having an information body part including at least information body and an additional part including information for receiving field intensity measurement by using a plurality of antennas according to each receiving field intensity,
 wherein part of a synchronization period of the information body part is set at part or all of a receiving field intensity measurement period of the additional part to use a synchronization signal of the synchronization period as a signal for receiving field intensity measurement.   
     
     
         20 . The receiving apparatus according to  claim 19 , comprising an antenna changeover unit that is connected to each antenna in correspondence to arrangement positions of the plurality of antennas and detects a connection state of each antenna to change over the connected antennas according to an instruction,
 wherein the controller selects and changes to an antenna whose connection has been detected by the antenna changeover unit.   
     
     
         21 . A receiving apparatus for selecting and receiving a radio signal in a frame structure having an information body part including at least information body and an additional part including information for receiving field intensity measurement by using a plurality of antennas according to each receiving field intensity,
 wherein part of a synchronization period of the information body part is set at part or all of a receiving field intensity measurement period of the additional part to use a synchronization signal of the synchronization period as a signal for receiving field intensity measurement, and the antenna for receiving field measurement and the antenna for receiving the information body part are changed over in the synchronization period according to a measurement result of a receiving field intensity to each of the plurality of antennas.   
     
     
         22 . The receiving apparatus according to  claim 21 , wherein the antenna for receiving field measurement is changed over in the receiving field intensity measurement period to measure a receiving field intensity of each antenna. 
     
     
         23 . The receiving apparatus according to  claim 21 , comprising an antenna changeover unit that is connected to each antenna in correspondence to arrangement positions of the plurality of antennas and detects a connection state of each antenna to change over the connected antennas according to an instruction,
 wherein the controller selects and changes to an antenna whose connection has been detected by the antenna changeover unit.   
     
     
         24 . A receiving apparatus for receiving a radio signal in a frame structure having an information body part including at least information body as a radio signal transmitted from a moving transmitting apparatus and an additional part including information for receiving field intensity measurement, the receiving apparatus comprising:
 an antenna changeover unit that is connected to each antenna in correspondence to arrangement positions of the plurality of antennas and detects a connection state of each antenna to change over the connected antennas according to an instruction, and   a controller that sequentially changes to an antenna whose connection has been detected by the antenna changeover unit on reception of the additional part to detect a receiving field intensity, and changes to an antenna having the largest receiving field intensity to cause the antenna to receive a radio signal of the information body part.   
     
     
         25 . The receiving apparatus according to  claim 24 , wherein a number of the plurality of antennas is less than a number of the plurality of connecting portions, and the plurality of antennas are used by replacing part of a plurality of already connected antennas with other connecting portions. 
     
     
         26 . The receiving apparatus according to  claim 24 , wherein the controller measures receiving field intensities of a plurality of antennas in a receiving period of the additional part.