Radio base station, relay station and radio communication method

Abstract

A relay station that includes a receiver configured to receive a signal sequence indicating a connection request, the signal sequence being selected from a predetermined signal sequence group which is used by a plurality of radio terminals, and to measure reception quality; and a control circuit configured to generate a ranging request message indicating that a radio terminal requesting connection exists when determining that adjustments are not necessary based on the reception quality; and a transmitter configured to transmit the ranging request message to a radio base station.

What is claimed is: 
     
         1 . A relay station comprising:
 a receiver configured to receive a signal sequence indicating a connection request, the signal sequence being selected from a predetermined signal sequence group which is used by a plurality of radio terminals, and to measure reception quality;   a control circuit configured to generate a ranging request message indicating that a radio terminal requesting connection exists when determining that adjustments are not necessary based on the reception quality; and   a transmitter configured to transmit the ranging request message to a radio base station.   
     
     
         2 . The relay station as claimed in  claim 1 , wherein:
 the reception quality is one of timing offset, power offset, or frequency offset.   
     
     
         3 . A radio communication method comprising:
 in a relay station, receiving a signal sequence indicating a connection request, the signal sequence being selected from a predetermined signal sequence group which is used by a plurality of radio terminals;   measuring reception quality;   generating a ranging request message indicating that a radio terminal requesting connection exits when determining that adjustments are not necessary based on the reception quality; and   transmitting the ranging request message to a radio base station.   
     
     
         4 . The radio communication method as claimed in  claim 3 , wherein: the receipt quality is one of timing offset, power offset, or frequency offset.