Patents by Inventor Malik J. Khan

Malik J. Khan 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: 6069886
    Abstract: A two-way wireless selective call communication system (20) using a synchronous time division multiplex communication protocol transmits messages divided into a plurality of data units (120, 126, and 128) from a plurality of selective call transceivers (32) to a paging terminal (33) during time slots (78), the number of data units and the time slots are set by the paging terminal controller (26) based on information, including size of the message information, received in an unscheduled transmission from each of the plurality of selective call transceivers. The paging terminal transmits to a selective call transceiver a multi-bit acknowledgment message having a one-bit acknowledgment for each of the plurality of data units. A selective call transceiver re-transmits data units not recovered by the terminal based upon content of the acknowledgment message. More than one selective call transceiver transmit during a one time slot set by the terminal.
    Type: Grant
    Filed: December 22, 1997
    Date of Patent: May 30, 2000
    Inventors: Douglas I. Ayerst, Malik J. Khan, Michael J. Rudowicz
  • Patent number: 5799012
    Abstract: A two-way wireless selective call communication system (20) using a synchronous time division multiplex communication protocol transmits messages divided into a plurality of data units (120, 126, and 128) from a plurality of selective call transceivers (32) to a paging terminal (33) during time slots (78), the number of data units and the time slots are set by the paging terminal controller (26) based on information, including size of the message information, received in an unscheduled transmission from each of the plurality of selective call transceivers. The paging terminal transmits to a selective call transceiver a multi-bit acknowledgment message having a one-bit acknowledgment for each of the plurality of data units. A selective call transceiver re-transmits data units not recovered by the terminal based upon content of the acknowledgment message. More than one selective call transceiver transmit during a one time slot set by the terminal.
    Type: Grant
    Filed: January 5, 1996
    Date of Patent: August 25, 1998
    Assignee: Motorola, Inc.
    Inventors: Douglas I. Ayerst, Malik J. Khan, Michael J. Rudowicz
  • Patent number: 5793756
    Abstract: A system controller (102) generates and transmits a radio signal having long messages in data frames (370), and short and long messages in control frames (360). A set of selective call radio addresses is included at the beginning of a control frame (360), each selective call radio address including a subvector which indicates the starting position of a short message or a vector packet within the control frame (360). Vector packets indicate starting positions of long messages within the control frame (360), within other control frames (360), and within data frames (370). A selective call radio (106) receives the radio signal and recovers and processes the short and long messages, using the subvectors and vectors to identify the positions of the short and long messages.
    Type: Grant
    Filed: November 19, 1996
    Date of Patent: August 11, 1998
    Assignee: Motorola, Inc.
    Inventors: Douglas Irvin Ayerst, Malik J. Khan, Michael James Rudowicz
  • Patent number: 5740534
    Abstract: A selective call receiver (106) has a frequency synthesizer (708) for scanning a plurality of frequencies to determine a control channel to receive a signal and a receiver (704) for receiving the signal representative of an available frequency associated with a geographic region. The signal includes a channel identifier (404), a frequency assignment (406) and an active channel indicator (408). A processor (712) associates the channel identifier (404) with the frequency assignment (406) in response to the active channel indicator (408) indicating an available frequency of the geographic region and a memory (720) stores channel identifiers (404) associated with frequency assignments (406) designating available frequencies (408).
    Type: Grant
    Filed: February 22, 1996
    Date of Patent: April 14, 1998
    Assignee: Motorola, Inc.
    Inventors: Douglas I. Ayerst, Malik J. Khan, Morris Moore, Leonard E. Nelson, Kwok K. Choi
  • Patent number: 5644568
    Abstract: A system controller (102) generates and transmits a radio signal having long messages in data frames (370), and short and long messages in control frames (360). A set of selective call radio addresses is included at the beginning of a control frame (360), each selective call radio address including a subvector which indicates the starting position of a short message or a vector packet within the control frame (360). Vector packets indicate starting positions of long messages within the control frame (360), within other control frames (360), and within data frames (370). A selective call radio (106) receives the radio signal and recovers and processes the short and long messages, using the subvectors and vectors to identify the positions of the short and long messages.
    Type: Grant
    Filed: March 15, 1995
    Date of Patent: July 1, 1997
    Assignee: Motorola, Inc.
    Inventors: Douglas Irvin Ayerst, Malik J. Khan, Michael James Rudowicz
  • Patent number: 5638369
    Abstract: A system controller (102) is used in a communication system (100) which has a set of inbound channels. The system controller (102) includes a processing system (204) for generating a first message which is transmitted to selective call devices (106). The first message includes a subset identifier which identifies an ALOHA subset of the set of inbound channels for use by a set of the selective call devices (106). A selective call device (106) includes a transmitter (708) and a processing system (710). The processing system (710) identifies the ALOHA subset of the set of inbound channels, and generates a second message and couples the second message to the transmitter (708) using an ALOHA protocol on an inbound channel which is in the ALOHA subset of the set of inbound channels when the second message is a first type. The transmitter (708) transmits the second message.
    Type: Grant
    Filed: July 5, 1995
    Date of Patent: June 10, 1997
    Assignee: Motorola, Inc.
    Inventors: Douglas I. Ayerst, Gregory Cannon, Malik J. Khan, Richard A. Hill
  • Patent number: 5521926
    Abstract: A fixed system receiver (107), which includes a forward receiver (305), a reverse receiver (310), and a response timer (215), is for use in a radio communication system (100) having a forward radio channel and a reverse radio channel. A command is transmitted in a forward channel radio signal to a selective call transceiver. The forward receiver (305) is for receiving, demodulating, and decoding the command. The reverse receiver (310) is for receiving and demodulating the reverse channel radio signal. The response timer (215), which is coupled to the forward receiver (305) and the reverse receiver (310), is for determining a response period beginning substantially at a scheduled response time included in the command and having a duration which is substantially a designated length of the data unit included in the command, and for generating a control signal which enables the reverse receiver (310) during the response period.
    Type: Grant
    Filed: August 1, 1994
    Date of Patent: May 28, 1996
    Assignee: Motorola, Inc.
    Inventors: Douglas I. Ayerst, Brian J. Budnik, Malik J. Khan