  We demonstrate a strong correlation between the magnetoresistive and the
concurrent microwave reflection from the microwave photo-excited GaAs/AlGaAs
two-dimensional electron system (2DES). These correlations are followed as a
function of the microwave power, the microwave frequency, and the applied
current. Notably, the character of the reflection signal remains unchanged even
when the current is switched off in the GaAs/AlGaAs Hall bar specimen. The
results suggest a perceptible microwave-induced change in the electronic
properties of the 2DES, even in the absence of an applied current.
