Patents by Inventor Charles S. Robertson

Charles S. Robertson has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6111462
    Abstract: An RF power amplifier linearization architecture has a pair of matched RF amplifiers, RF signal paths through which are intercoupled with a phase and amplitude measurement and predistortion mechanism. By selectively combining the RF output of a main path RF power amplifier with the RF input signal supplied to a parallel path RF power amplifier, the predistortion control mechanism of the invention predistorts the RF input signal applied to the parallel path amplifier, so that it includes the same modulated RF carrier component as that applied to the main path amplifier, as well as a complementary version of the intermodulation component of the output of the main path amplifier. The predistortion for each amplifier is controlled such that the resulting RF output signals produced by the matched amplifier pair will have the desired RF carrier modulation component but equal amplitude and phase-reversed intermodulation components.
    Type: Grant
    Filed: November 18, 1998
    Date of Patent: August 29, 2000
    Inventors: Lance T. Mucenieks, Charles S. Robertson, Brent L. Irvine, Nemy Salvador
  • Patent number: 4232367
    Abstract: A calculator apparatus is provided for computing minimum principal amounts for deposit into demand (passbook) accounts and into term (certificate-of-deposit) accounts paying interest at differing rates. The computed minimum principal amounts not only satisfy the minimum deposit requirements of the term accounts but, when deposited, provide both maximum interest earnings and payments from principal, without interest penalty ordinarily associated with early withdrawals. The apparatus comprises a keyboard, a read-write memory, a logic unit, a printer, and a display unit. The logic unit includes an arithmetic unit having a plurality of data storage registers and a read-only-memory with a stored program. The apparatus computes the minimum principal amounts in accordance with the stored program and in response to entered data.
    Type: Grant
    Filed: June 12, 1978
    Date of Patent: November 4, 1980
    Inventors: Robert H. Youden, Charles S. Robertson