  We tested a new model of CMOS detector manufactured by the Gpixel Inc, for
potential space astronomical application. In laboratory, we obtain some bias
images under the typical application environment. In these bias images, clear
random row noise pattern is observed. The row noise also contains some
characteristic spatial frequencies. We quantitatively estimated the impact of
this feature to photometric measurements, by making simulated images. We
compared different bias noise types under strict parameter control. The result
shows the row noise will significantly deteriorate the photometric accuracy. It
effectively increases the readout noise by a factor of 2 to 10. However, if it
is properly removed, the image quality and photometric accuracy will be
significantly improved.
