Transmission line impedance characteristics of the design is the most important factor in
Transmission line impedance of the moment or is characteristic impedance signal quality is affected the most important factor. If the signal transmission process, the adjacent signal transmission line spacing between the resistance, then the signals can be transmitted to move forward very smooth laptop battery and therefore the situation has become very simple. If the adjacent signal transmission between different intervals, or impedance has changed, the signal will be part of the energy back reflection, the continuity of signal transmission will be destroyed.
In order to ensure the best signal quality and design of the Internet signal the goal is to ensure that the signal transmission seen in the course of the impedance, as far as possible to maintain constant unchanged. Here is mean to maintain the characteristics of transmission lines for the constant impedance. Therefore, production design controlled impedance of the PCB board has become increasingly important inspiron battery. And for any other tips such as the minimum length of Goldfinger, the terminal match, daisy chain link or branches are connected, and so on in order to ensure that the signal be able to see the same moment impedance.
Often heard about the transmission line impedance characteristics of some of the confusion is. Through the above analysis that will signal source connected to the transmission lines, should be able to see a certain value of the transmission line impedance characteristics Inspiron 8100 battery , for example, 50 Ω, but if a ohmmeter three feet long with a section of the RG58 cable connection, To the impedance measurement is infinite.
The answer lies in front of any transmission line to see the last of the resistance value is changing with time. If the cable impedance measurement of the time is short and can signal to the cable in the back and forth from one time to compare, you can measure the cable to the surge impedance cable or also known as the characteristic impedance. If, however, waiting for enough time, they would have to return part of the energy Inspiron 4000 battery reflection and measuring instruments to detect, at this time can detect changes in impedance, under normal circumstances, in this process, the resistance will change back and forth, until the resistance value To achieve a stable condition: If the cable end is open, the ultimate value of infinite impedance, if the end of the cable short-circuit, the final value of zero impedance.
For three feet long RG58 cable, must be less than 3 ns in the time interval to complete the impedance measurement process. This is the time domain reflectometer (TDR) to complete the work. TDR can measure the dynamic impedance transmission lines. If you need to spend 1 s time intervals to measure 3 feet long RG58 cable resistance, then the time interval Inspiron 600m battery in which the signal has been reflecting the return of millions of times, then you may resistance from the tremendous changes in completely different impedance The value and ultimately the result is infinite, because the cable terminal is open.