A wireless sensor for measuring a light intensity is operable to transmit wireless signals using a variable transmission rate that is dependent upon the light intensity in the space. The sensor comprises a photosensitive circuit, a wireless transmitter for transmitting the wireless signals, and a controller coupled to the photosensitive circuit and the wireless transmitter. The photosensitive circuit is operable to generate a light intensity control signal in response to the light intensity. The controller transmits the wireless signals in response to the light intensity control signal using the variable transmission rate that is dependent upon an amount of change of the light intensity. In addition, the variable transmission rate may be further dependent upon a rate of change of the light intensity. The sensor may further comprise a battery for powering the photosensitive circuit, the wireless transmitter, and the controller.