High speed communication apparatus for computerized axial tomography (CAT) scanners with matching receiver

A communications apparatus for providing high speed communications between first and second electronics systems mounted on first and second mechanical mounting structures, respectively, where the first and second mechanical mounting structures rotate with respect to each other along an axis of rotation, the apparatus comprising:

• a first slip ring arranged coaxially with the axis of rotation between the first and second mechanical mounting structures;
• drive means mounted on the first mechanical mounting structure and connected to the first electronics system for transmitting an electrical signal voltage onto the first slip ring, the electrical signal voltage being referenced to a signal ground reference potential and being encoded with data to be communicated from the first electronics system to the second electronics system, the drive means -including first connection means for making contact with the first slip ring at a first point in the frame of reference of the first mechanical mounting structures;
• termination means mounted on the first mechanical mounting structure for providing termination of the electrical signal voltage on the first slip ring, the termination means including:
• second connection means for making contact with the first slip ring at a second point in the frame of reference of the first mechanical mounting structure, the first and second points in the frame of reference of the first mechanical mounting structure being located approximately diametrically opposite each other across the first slip ring;
• and
• a resistive termination connected between the second connection means and the signal ground reference potential;
• receive means connected to the second electronic system on the second mechanical mounting structure for receiving the electrical signal voltage on the first slip ring, the receive means including third connection means for making contact with the first slip ring at a first point in the frame of reference of the second mechanical mounting structure to receive the electrical signal voltage from the first slip ring;
• and
• matching receive means mounted on the second mechanical mounting structure for providing a signal delay approximately equal to that of the receive means, the matching receive means including fourth connection means for making contact with the first slip ring at a second point in the frame of reference of the second mechanical mounting structure to receive the electrical signal voltage from the first slip ring, the first and second points in the frame of reference of the second mechanical mounting structure being located approximately diametrically opposite each other across the first slip ring.