The amount of information that can be transferred depends on the carrier frequency and available RF channel bandwidth. Digital data at a specific rate can be considered a square wave at a frequency of Data Rate divided by 2 Hertz. A 56kbps data stream can be considered a 28kHz signal. The RF channel bandwidth must be wider than 28kHz to contain the data. The carrier frequency must be many times the required bandwidth; thus, applications such as video and data links (which require wide bandwidths) utilize frequencies well into the microwave range. In general, the bandwidth should be as narrow as possible to accommodate the required information content. This will result in the best immunity to noise and allows the highest possible system sensitivity.