John W Kramer

US Patent:

58125892, Sep 22, 1998

Filed:

May 18, 1995

Appl. No.:

8/444168

Inventors:

Wanda Sealander - San Jose CA
John W. Kramer - Allison Park PA

Assignee:

Symbol Technologies, Inc. - Holtsville NY

International Classification:

H04B 1500
H04K 100
H04L 2730

US Classification:

375200

Abstract:

A packet data transmission system is disclosed in which remote units, such as remote hand-held data gathering units, which normally communicate with remote base stations via a spread spectrum RF communications, are initialized via spread spectrum RF communications. A network chipping sequence is provided for encoding normal communications and a universal chipping sequence is provided for encoding communications relating to initialization of the remote units. The network chipping sequence is adjustable and must be initialized in each of the remote units to enable normal communications. The universal chipping code is fixed for all remote devices and base stations. Since the universal chipping code is fixed, spread spectrum RF communications of the initialization data, using the universal chipping code, can be effected even if the network chipping sequence is not initially set in the remote units. The initialization data communicated to the remote includes the network chipping code which is then stored in the remote units and used for subsequent normal communications.

US Patent:

54794412, Dec 26, 1995

Filed:

Jan 18, 1994

Appl. No.:

8/183069

Inventors:

LaRoy Tymes - Palo Alto CA
John W. Kramer - Allison Park PA

Assignee:

Symbol Technologies - Bohemia NY

International Classification:

H04B 169

US Classification:

375200

Abstract:

A packet data transmission system is used to link a number of remote hand-held data-gathering units such as bar code readers to a central computer which maintains a database management system. Data packets are sent from the remote units by an RF link to intermediate base stations, then sent by the base stations to the central computer by a serial link. Direct sequence spread spectrum modulation is used for the RF link. The remote hand-held units initiate an exchange using RF transmission to and from the base stations, receiving only during a rigid time window following a transmission from the remote unit. The base stations cannot initiate communication to the remote units, but instead send data to the remote units only as part of the exchange.

US Patent:

52804984, Jan 18, 1994

Filed:

Nov 27, 1991

Appl. No.:

7/799172

Inventors:

LaRoy Tymes - Palo Alto CA
John W. Kramer - Allison Park PA

Assignee:

Symbol Technologies, Inc. - Bohemia NY

International Classification:

H04L 900

US Classification:

375 1

Abstract:

A packet data transmission system is used to link a number of remote hand-held data-gathering units such as bar code readers to a central computer which maintains a database management system. Data packets are sent from the remote units by an RF link to intermediate base stations, then sent by the base stations to the central computer by a serial link. Direct sequence spread spectrum modulation is used for the RF link. The remote hand-held units initiate an exchange using RF transmission to and from the base stations, receiving only during a rigid time window following a transmission from the remote unit. The base stations cannot initiate communication to the remote units, but instead send data to the remote units only as part of the exchange.

US Patent:

60699116, May 30, 2000

Filed:

Mar 10, 1998

Appl. No.:

9/038195

Inventors:

Wanda Sealander - San Jose CA
John W. Kramer - Allison Park PA

Assignee:

Symbol Technologies - Holtsville NY

International Classification:

A61F 206

US Classification:

375130

Abstract:

A packet data transmission system is disclosed in which remote units, such as remote hand-held data gathering units, which normally communicate with remote base stations via a spread spectrum RF communications, are initialized via spread spectrum RF communications. A network chipping sequence is provided for encoding normal communications and an universal chipping sequence is provided for encoding communications relating to initialization of the remote units. The network chipping sequence is adjustable and must be initialized in each of the remote units to enable normal communications. The universal chipping code is fixed for all remote devices and base stations. Since the universal chipping code is fixed, spread spectrum RF communications of the initialization data, using the universal chipping code, can be effected even if the network chipping sequence is not initially set in the remote units. The initialization data communicated to the remote includes the network chipping code which is then stored in the remote units and used for subsequent normal communications.

US Patent:

20140092759, Apr 3, 2014

Filed:

Oct 3, 2012

Appl. No.:

13/644243

Inventors:

- Schaumburg IL, US
John Kramer - Los Gatos CA, US

Assignee:

Motorola Solutions, Inc. - Schaumburg IL

International Classification:

H04W 24/00

US Classification:

370252

Abstract:

A method and apparatus for locationing using differential phase measurements of IEEE 802.11 preambles. A first step includes providing a local clock at the same frequency as the IEEE 802.11 preambles. This step includes synchronizing the local clocks at multiple receivers with a reference clock, for example, using Synchronous Ethernet. A next step includes receiving IEEE 802.11 packets from a transmitter by at least three fixed receivers. A next step includes determining a phase offset between the local clock and any nearest cycle of a preamble in the received packets in each of the receivers. A next step includes locating the transmitter using each of the phase offsets.