Signal bandwidth: Spectrum highest frequency sine wave component value effectively.
A rising edge approximate relation bandwidth: BW = 0.35 / RT
Wherein, BW represents the bandwidth (in GHz), RT represents 10% to 90% of the rising edge (in ns). For a typical 10MHz clock signal rising edge typically 10ns, which bandwidth is about 35MHz.
PS: To reduce electromagnetic interference, the design should be used in all possible low bandwidth signal. Above this bandwidth, harmonic amplitude than the 1 / f fall quickly, the radiation will have smaller effect on. The bandwidth is kept at a minimum, the radiation amount will be kept to a minimum. Rising edge of the signal bandwidth is directly related to
Two rising edge of clock cycle of approximate relation :
Is generally assumed that the rising edge of the clock cycle 7%, the relationship between the bandwidth and the clock frequency is BWclock = 5 × Fclock
Under this assumption, a typical maximum clock frequency component sinusoidal waveform is the 5th harmonic.
Three Internet bandwidth
Interconnection bandwidth is the maximum that can be interconnected transmission and does not cause loss of effective components of the sine wave frequency.
PS: In general, in the actual use of "effective" refers to the frequency component of the amplitude of the transmission is reduced 3dB, that is reduced to 70% of the incident amplitude value. This is often referred to interconnect 3dB bandwidth . (Example: If a 3dB bandwidth interconnects about 8GHz, which means that if a sine wave input 8GHz, then the distal end of the signal amplitude obtained at most 70% of the original signal, Further, if the bandwidth of the interconnection . 8GHz, 1GHz then transmitted to the distal end of the sine wave almost 100% interconnected if desired square wave transmitted through the interconnect is lower than the respective sinusoidal components can be transmitted to 8GHz, before and after the transmission is substantially the same amplitude; but the high 8GHz to the amplitude component will become no longer valid. 1ps a rising edge of a signal, after transmission of the interconnection, which may be the rising edge 0.35 / 8GHz = 0.043ns, i.e. 43ps, indicating that the rising interconnection edge degraded.)
Internet bandwidth is a direct measure for the shortest interconnect can transmit signals of a leading edge.
If the interconnection bandwidth is 1GHz, it can transmit fastest edge is 350ps, which is interconnected intrinsic rising edge .
If a rising edge of the signal into the interconnected as 50ps, the rising edge at its output Calculated:
PS:. 1 an additional amount such that the leading edge of the signal interconnection caused less than 10%, an intrinsic interconnected side will rise less than 50% of the rising edge of the signal
2. From the perspective of the frequency domain, preferably to a signal transmission bandwidth of 1GHz, interconnect bandwidth should be at least twice the bandwidth of the signal for, i.e. 2GHz
