Telecommunication
The other meaning of the term "channel" in telecommunications is seen in the phrase communications channel, which is a subdivision of a transmission medium so that it can be used to send multiple streams of information simultaneously. For example, one radio station can broadcast radio waves into free space at frequencies in the neighborhood of 94.5 MHz (megahertz) while another radio station can simultaneously broadcast radio waves at frequencies in the neighborhood of 96.1 MHz. Each radio station would transmit radio waves over a frequency bandwidth of about 180 kHz (kilohertz), centered at frequencies such as the above, which are called the "carrier frequencies". Each station in this example is separated from its adjacent stations by 200 kHz, and the difference between 200 kHz and 180 kHz (20 kHz) is an engineering allowance for the imperfections in the communication system.
List of 2.4 GHz radio use
Amateur Radio operators can transmit two-way Amateur television (and voice) in the 2.4 GHz band - and all ISM frequencies above 902 MHz - with maximum power of 1500 watts in the US if the transmission mode does not include spread spectrum techniques. Other power levels apply per regions. In the UK, the maximum power level for a full licence is 400 watts. In other countries, maximum power level for non - spread spectrum emissions are set by local legislation. 
Although the transmitter of some video cameras appears to be fixed on one frequency, it has been found in several models that the cameras are actually frequency agile, and can have their frequency changed by disassembling the product and moving solder links or dip switches inside the camera.