High-pass/low-pass phase shifter spreadsheet

Updated January 20, 2009

Click here to go to our main page on phase shifters

Click here to go to our original page on HP/LP phase shifters

The spreadsheet that is described on this page is available in our download area, it's called HP_LP_Phase_Shifter101.xls.

New for January 2009! Now we have a tool for taking a quick look at the ideal frequency response of a high-pass/low-pass phase shifter. This provides just the ideal responses of the filters, and does not include any real loss of the filters or the two SPDT switches that are required. But what did you expect for free?

In the spreadsheet, we solve for both tee and pi networks so you can have your choice (ideally they provide the same response). However, we chose to use the tee network to solve for the frequency responses. The equations for determining ABCD parameters from a generalized tee network can be found on this page. Then it's just a matter of simple algebra to come up with the reduced equations for the two filters (lots of minus signs to keep track of, back off on the gin!)

Low pass network and ABCD parameter	High-pass network and ABCD parameters

Now that we did the heavy lifting, all you need to do is enter the following:

Center frequency

System impedance

Phase shift in the high-pass arm (at center frequency)

Phase shift in low pass arm (at center frequency)

Here's the plots you get when you are analyzing a 10 GHz, 180 degree phase shifter:

The red line is the difference in phase between the two filters. Sweet!

More to come!