Patents by Inventor Sukla R. Das

Sukla R. Das 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).

  • Reducing power consumption in low noise radiophone amplifiers
    Patent number: 5978690
    Abstract: The battery life of a portable radiotelephone is increased by providing a variable instead of a fixed value of collector-emitter current for the low noise transistor in the RF receiving stage. In particular, the collector current of the RF receiving stage is microprocessor controlled in inverse proportion to the strength of the received signal, an indication of which is advantageously taken from the normally provided "RSSI" output signal provided by the radiotelephone set's conventional IF chip. The microprocessor stores an indication of the correct amount of base current drive to be supplied to the RF transistor to determine its collector current for strong signal and weak signal conditions as well as monitoring collector current for varying base drive to compensate for temperature effects.
    Type: Grant
    Filed: February 25, 1997
    Date of Patent: November 2, 1999
    Assignee: Lucent Technologies Inc.
    Inventors: Sukla R. Das, Emanuil Y. Shvarts