3dB cutoff frequency

The basic difference between the two is that frequency is defined as the rate of radio signal to send and receive communication signals, whereas bandwidth is defined as the difference between the highest and the lowest frequencies of a signal generated .

Bandwidth is measured between the 0.707 current amplitude points. The 0.707 current points correspond to the half power points since P = I 2R , (0.707)2 = (0.5). Bandwidth, Δf is measured between the 70.7% amplitude points of series resonant circuit.

Rise time and 3 dB bandwidth are inversely proportional , with a proportionality constant of ~0.35 when the system’s response resembles that of an RC low-pass filter.

Bandwidth, also referred to as Frequency Response, is an indication of a displacement sensor’s ability to respond to changes in the measured displacement . It is measured at the -3dB point and gives indication of: How the output changes relative to the frequency of a vibrating target.

Bandwidth is given as the range between these frequencies. For a high pass filter, the cut off frequency will define the lower value of bandwidth . For a low pass filter, the cutoff frequency will define the higher value of bandwidth.