A communication control method for a base station (MeNB, SeNB) and a user apparatus to perform radio communication with each other, the base station (MeNB, SeNB) performing radio communication with the user apparatus using multiple antennas and a massive MIMO transmission scheme, wherein there are set multiple antenna groups that each include all or a portion of the antennas and multiple antenna group patterns that each include at least one of the antenna groups, the method comprising: transmitting in parallel, from the base station, reference signals with sequences that differ from one another between antenna groups that are included in a same antenna group pattern; receiving the reference signals in the user apparatus; and determining, based on a reception result of the reference signals, a use antenna group pattern and at least one use antenna group that are to be used for transmission of a radio signal from the base station, the use antenna group pattern being determined from among the multiple antenna group patterns, the at least one use antenna group being determined from among the multiple antenna groups, determining, based on the reception result of the reference signals, a transmission beam angle for each of the at least one use antenna group that is included in the use antenna group pattern, wherein the multiple antenna group patterns includes a first to an N-th, where N is a natural number of two or more, antenna group patterns, and a number of antenna groups included in an n-th, where n is a natural number satisfying N ≥ n ≥ 2, antenna group pattern is greater than a number of antenna groups included in an (n-1)-th antenna group pattern, and wherein in determining the transmission beam angle, the transmission beam angle is determined in order from an antenna group pattern that includes fewest antenna groups, and at least one transmission beam angle is determined for the n-th antenna group pattern based on at least one transmission beam angle that is determined for the (n-1)-th antenna group pattern, and wherein for each antenna group pattern that includes multiple antenna groups, the multiple antennas of the base station are sectioned into those multiple antenna groups, and each antenna of the base station is included in one of those multiple antenna groups belonging to that antenna group pattern, and wherein the number of antennas included in each antenna group differs between the antenna group patterns. transmitting in parallel, from the base station, reference signals with sequences that differ from one another between antenna groups that are included in a same antenna group pattern; receiving the reference signals in the user apparatus; and determining, based on a reception result of the reference signals, a use antenna group pattern and at least one use antenna group that are to be used for transmission of a radio signal from the base station, the use antenna group pattern being determined from among the multiple antenna group patterns, the at least one use antenna group being determined from among the multiple antenna groups, determining, based on the reception result of the reference signals, a transmission beam angle for each of the at least one use antenna group that is included in the use antenna group pattern, wherein the multiple antenna group patterns includes a first to an N-th, where N is a natural number of two or more, antenna group patterns, and a number of antenna groups included in an n-th, where n is a natural number satisfying N ≥ n ≥ 2, antenna group pattern is greater than a number of antenna groups included in an (n-1)-th antenna group pattern, and wherein in determining the transmission beam angle, the transmission beam angle is determined in order from an antenna group pattern that includes fewest antenna groups, and at least one transmission beam angle is determined for the n-th antenna group pattern based on at least one transmission beam angle that is determined for the (n-1)-th antenna group pattern, and wherein for each antenna group pattern that includes multiple antenna groups, the multiple antennas of the base station are sectioned into those multiple antenna groups, and each antenna of the base station is included in one of those multiple antenna groups belonging to that antenna group pattern, and wherein the number of antennas included in each antenna group differs between the antenna group patterns.