Why in smithchart 360 degree corresponds to half the wavelength

  • Thread starter Thread starter dexterdev
  • Start date Start date
  • Tags Tags
    Degree Wavelength
AI Thread Summary
In a Smith chart, 360 degrees corresponds to one full wavelength (λ), but a half wavelength (λ/2) represents a significant change in the reflection coefficient. A short circuit on a transmission line has a reflection coefficient of -1, plotted on the left side of the Smith chart. Lengthening the transmission line by 1/4 wavelength transforms the reflection coefficient to +1, resembling an open circuit, and moves the point to the right side of the chart. This movement illustrates that extending the line by 1/4 wavelength effectively shifts the point halfway around the Smith chart. Understanding this relationship is crucial for accurate impedance matching in RF applications.
dexterdev
Messages
194
Reaction score
1
Hi,
Actually wavelength λ corresponds to 360 degrees , right? then why λ/2...
 
Engineering news on Phys.org
Don't expect Smith chart to work like an Argand diagram.

Consider a short circuit on an electrically short transmission line. This will have reflection coefficient of -1, which will be plotted on the far left side of Smith chart. If I lengthen transmission line by 1/4 wavelength in front of short circuit, it will have a reflection coefficient of +1 (i.e. it will look like an open circuit), which will be plotted on the far right hand side of Smith chart. Extending transmission line 1/4 wavelength moved us halfway around Smith chart.
 
Hi all I have some confusion about piezoelectrical sensors combination. If i have three acoustic piezoelectrical sensors (with same receive sensitivity in dB ref V/1uPa) placed at specific distance, these sensors receive acoustic signal from a sound source placed at far field distance (Plane Wave) and from broadside. I receive output of these sensors through individual preamplifiers, add them through hardware like summer circuit adder or in software after digitization and in this way got an...
I have recently moved into a new (rather ancient) house and had a few trips of my Residual Current breaker. I dug out my old Socket tester which tell me the three pins are correct. But then the Red warning light tells me my socket(s) fail the loop test. I never had this before but my last house had an overhead supply with no Earth from the company. The tester said "get this checked" and the man said the (high but not ridiculous) earth resistance was acceptable. I stuck a new copper earth...
Thread 'Beauty of old electrical and measuring things, etc.'
Even as a kid, I saw beauty in old devices. That made me want to understand how they worked. I had lots of old things that I keep and now reviving. Old things need to work to see the beauty. Here's what I've done so far. Two views of the gadgets shelves and my small work space: Here's a close up look at the meters, gauges and other measuring things: This is what I think of as surface-mount electrical components and wiring. The components are very old and shows how...
Back
Top