  In order to explore any change caused by the G2 cloud approaching, we have
monitored the flux density of Sgr A* at 22 GHz from Feb. 2013 to Aug. 2014 with
a sub-array of Japanese VLBI Network . The observation period included the
expected periastron dates. The number of observation epochs was 283 days. We
have observed no significant microwave enhancement of Sgr A* in the whole
observation period. The average flux density in the period is $S=1.23+/-0.33$
Jy. The average is consistent with the usually observed flux density range of
Sgr A* at 22 GHz.
