US 2006/0125573 A1 · Novel radio frequency (RF) circuit board topology

Abstract

An interconnection structure for interconnecting circuitry on a first conductive layer to circuitry on a second conductive layer is provided. The interconnection structure of the present invention comprises a signal conductor via surrounded by a plurality of ground vias. The plurality of ground vias shield the signal conductor via, thus providing electrical isolation for the conductor via from the rest of the circuitry. One feature of the present invention is that the plurality of ground vias can be modified, adjusting their diameters and their placement relative to the signal conductor via, in order to affect the overall characteristic impedance of the interconnection structure. This feature is useful when propagating high frequency signals between signal traces on different conductive layers of a printed circuit board. In view of the high frequencies used in today's wireless communication systems, the interconnection structure proposed aids in the practical implementation of radio frequency modules by mitigating the effects of impedance discontinuities ordinarily present at signal trace-to-via transition regions.

Claims29

Dependent claims

In a radio frequency circuit, an interconnection structure to connect a first conductive trace on a first conductive layer of a circuit board to a second conductive trace on a second conductive layer of the circuit board, the interconnection structure comprising:

a centre signal conductor via connected at a first end to the first conductive trace and connected at a second end to the second conductive trace and wherein the signal conductor via propagates electrical signals between the first conductive trace on the first conductive layer and the second conductive trace on the second conductive layer of the circuit board;
and
a plurality of ground vias surrounding the centre signal conductor via, the plurality of ground vias having a position relative to the centre signal conductor via based upon a desired overall impedance of the interconnection structure.

In a radio frequency communication system, an antenna selection module for connecting at least one of a plurality of radio ports to at least one of a plurality of antenna ports, said antenna selection module comprising:

a first conductive layer having said at least one of a plurality of radio ports, said first conductive layer having at least one first conductive trace thereon and connected to said at least one of a plurality of radio ports;
a second conductive layer having said at least one of a plurality of antenna ports, said second conductive layer having at least one second conductive trace thereon and connected to said at least one of a plurality of antenna ports;
an interconnection structure comprising:
a signal conductor via connected at a first end to said at least one first conductive trace on said first conductive layer and at a second end to said at least one second conductive trace on said second conductive layer, said signal conductor via propagating electrical signals between said at least one first conductive trace on said first conductive layer to said at least one second conductive trace on said second conductive layer;
a plurality of ground vias surrounding said signal conductor via, said plurality of ground vias having a position relative to said signal conductor via based upon a desired overall impedance of the interconnection structure.

2 more elements

A multilayer printed circuit board for use in a radio frequency communication system, said multilayer printed circuit board comprising:

a first conductive layer having a first conductive trace formed thereon terminating at a first via pad;
a second conductive layer having a second conductive trace formed thereon terminating at a second via pad;
an interconnection structure comprising:
a signal conductor via connected at a first end to said first conductive trace by said first via pad and connected at a second end to said second conductive trace by said second via pad, wherein said signal conductor via propagates electrical signals between said first conductive trace on said first conductive layer and said second conductive trace on said second conductive layer;
and
a plurality of ground vias surrounding said signal conductor via, said plurality of ground vias having a position relative to said signal conductor via based upon a desired overall impedance of the interconnection structure.

3 more elements

Dependencies are inferred from the claim text.

Novel radio frequency (RF) circuit board topology

Life of this patent

Novel radio frequency (RF) circuit board topology

Life of this patent

Abstract

Claims29