Patents by Inventor Walter Herbert Erwin Widl

Walter Herbert Erwin Widl 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: 4075427
    Abstract: A system for phase division multiplex duplex communication over a two-wire circuit has a master terminal and a slave terminal. The master terminal comprises a modulator and a demodulator jointly connected to a first end of the two-wire circuit and arranged to transmit an outgoing AM-signal with an essentially non-suppressed carrier component constituting a pilot signal and to receive an incoming AM-signal with a considerably suppressed carrier component having a frequency identical to the frequency of the pilot signal. An oscillator circuit is arranged to supply the modulator and the demodulator with a first and secnd, respectively, oscillator signal having a respective frequency identical to the frequency of the pilot signal and having such a relative phasing that at the demodulator the phase of the second oscillator signal is phase displaced 90.degree. relative to the phase of the pilot signal.
    Type: Grant
    Filed: November 15, 1976
    Date of Patent: February 21, 1978
    Assignee: Telefonaktiebolaget L M Ericsson
    Inventors: Orjan Mats Mattsson, Walter Herbert Erwin Widl
  • Patent number: 4061881
    Abstract: A method and apparatus for generating a number of weakly correlated pseudorandom pulse trains which is especially useful for generation of noise signals utilized for measurements on telephone cables carrying PCM traffic The apparatus generates a number of mutually phase shifted versions of a binary pulse train which are sampled with individual sampling signals of the same nominal frequency.
    Type: Grant
    Filed: July 19, 1976
    Date of Patent: December 6, 1977
    Assignee: Telefonaktiebolaget L M Ericsson
    Inventor: Walter Herbert Erwin Widl
  • Patent number: 4053723
    Abstract: A method and an apparatus for measuring the bit error frequency in a cable caused by crosstalk from at least one disturbing pair to a disturbed pair at transmission of a 3-level coded PCM signal utilizes the fact that a PCM signal transferred on a pair and the disturbances superimposed on this signal by crosstalk from other pairs are mathematically uncorrelated. The amplitudes of the disturbances measured on the disturbed pair are sampled after equalization in a regenerator with a sampling frequency which equals the bit time frequency of the PCM signal intended for transmission on the pair. The number of detected sampling values whose magnitude exceeds a certain threshold value is a function of the estimated bit error frequency.
    Type: Grant
    Filed: May 14, 1976
    Date of Patent: October 11, 1977
    Assignee: Telefonaktiebolaget L M Ericsson
    Inventors: Juho Arras, Mats Orjan Mattsson, Walter Herbert Erwin Widl