Patents by Inventor Erkki Rantakari

Erkki Rantakari 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: 7050724
    Abstract: The invention relates to an optical receiver comprising a transimpedance amplifier having an input and an output, a photo detector (PD) for converting the optical power arriving at the receiver, an adjustable impedance element (D1) operationally connected to the input of the transimpedance amplifier, and control means (CU) for controlling the current passinh through the impedance element by adjusting the impedance of the impedance means. In order for the receiver to have a high dynamic range, the adjustable impedance element is a PIN diode and the control means comprise (a) separating means (LPU) for separating the direct voltage component from the output voltage of the transimpedance amplifier, and (b) means (VCU) for adjusting the voltage over the PIN diode directly on the basis of the separated direct voltage component.
    Type: Grant
    Filed: May 8, 2000
    Date of Patent: May 23, 2006
    Assignee: Nokia Corporation
    Inventor: Erkki Rantakari
  • Patent number: 6242732
    Abstract: The invention relates to an optical receiver comprising a transimpedance amplifier (21) and a photo detector (PD) for converting the optical power arriving at the receiver into electric current. To enable a good dynamic range to be achieved for the receiver in a simple way, the transimpedance amplifier is a differential amplifier provided with two inputs. Furthermore, the receiver comprises separating means (LPU) for separating a direct voltage component from the output voltage of the transimpedance amplifier and means (VCU) for supplying a direct voltage dependent on the direct current component to that input of the transimpedance amplifier which is different from the input used by the photo detector.
    Type: Grant
    Filed: May 8, 2000
    Date of Patent: June 5, 2001
    Assignee: Nokia Networks Oy
    Inventor: Erkki Rantakari