IR wireless is the use of wireless technology in devices or systems that convey data through infrared (IR) radiation.Infrared is electromagnetic energy at a wavelength or wavelengths somewhat longer than those of red light. IR wireless is used for short- and medium-range communications and control. Other systems operate in diffuse mode, also called scatter mode. IR wireless technology is used in intrusion detectors; home-entertainment control units; robot control systems; medium-range,line-of-sight laser communications; cordless microphones, headsets, modems, and printers and other peripherals. Itallows the robot to determine when it has come in close proximity to an object without coming into physical contact. The IR sensor consists of IR Emitter and IR Phototransistor. The resistance of the phototransistor decreases as the light from the IR LEDfall on it as a result the current start flowing through it.

Radio frequencies

Radio frequencies are high frequency alternating current (AC) signals that are passed along a
copper conductor and then radiated into the air via an antenna.
Radio frequency (RF) radiation is a subset of electromagnetic radiation with a wavelength of
100 km to 1 mm, which is a frequency of 3 kHz to 300 GHz respectively.
RF circuits are useful in controlling the wireless robots. RF module consists of a transmitter
and the receiver, the transmitter generate the RF signal of a particular frequency and the RF
receiver respond to that particular frequency signal.