Claims
- 1. A circuit board comprising:a conductive plane having de-gassing holes; a first bus trace substantially parallel to the conductive plane; a second bus trace substantially parallel to the conductive plane; and a dielectric disposed between the conductive plane and the first and second bus traces, the first bus trace with the conductive plane and dielectric providing a first transmission line and defining a first characteristic impedance to guide electromagnetic radiation having a first wavelength and the second bus trace with the conductive plane and dielectric providing a second transmission line and defining a second characteristic impedance to guide electromagnetic radiation having a second wavelength, wherein the de-gassing holes are substantial smaller than the first and second wavelengths, and wherein the first and second bus traces are positioned relative to the de-gassing holes so the first and second characteristic impedances are substantially equal to each other.
- 2. The circuit board as set forth in claim 1, wherein the de-gassing holes have diameters less than e-tenth of the minimum of the first and second wavelengths.
- 3. A circuit board comprising:a conductive plane having de-gassing holes; a first bus trace substantially parallel to the conductive plane; a second bus trace substantially parallel to the conductive plane; and a dielectric disposed between the conductive plane and the first and second bus traces, the first bus trace with the conductive plane and dielectric to guide electromagnetic radiation having a first wavelength and the second bus trace with the conductive plane and dielectric to guide electromagnetic radiation having a second wavelength, wherein the de-gassing holes are substantially smaller than the first and second wavelengths, wherein the first bus trace passes over a first local average of the de-gassing holes per unit length, wherein the second bus trace passes over a second local average of the de-gassing holes per unit length, and wherein the first and second bus traces are positioned relative to the de-gassing holes so that the first and second local averages of the de-gassing holes per unit length are substantially equal to each other.
- 4. The circuit board as set forth in claim 3, wherein the second and first local averages are defined over one quarter of the largest of the first and second wavelengths.
- 5. The circuit board as set forth in claim 3, wherein the de-gassing holes have diameters less than one-tenth of the minimum of the first and second wavelengths.
Parent Case Info
This application is a divisional of U.S. patent application Ser. No. 09/474,345 filed on Dec. 29, 1999.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
5519176 |
Goodman et al. |
May 1996 |
A |
6303871 |
Zu et al. |
Oct 2001 |
B1 |