John Charles Kramer

US Patent:

42453470, Jan 13, 1981

Filed:

Jan 18, 1978

Appl. No.:

5/870446

Inventors:

Thomas J. Hutton - Pittsburgh PA
John W. Kramer - Pittsburgh PA

International Classification:

H04B 106
H04Q 132

US Classification:

455 70

Abstract:

The invention is directed to a remote equipment control system having a low duty cycle communications link between a remote command transmitter and a remote receiver. The remote receiver is controllingly coupled to the equipment. The remote command transmitter includes a means to transmit a message signal of set time duration at a preselected message separation interval. The message signal has a unique address portion and a command portion. The remote receiver includes a decoding unit and a timing circuit. The decoding unit is responsive to the unique address portion of a received message to provide an enabling signal to be delivered to the timing circuit. The timing circuit upon receipt of the enabling signal provides an output to the decoding unit to prevent entry of any message signal to the decoder for a time duration matching the preselected message separation interval and allowing entry of a message signal for a time duration matching the time duration of the message signal. The enabling signal also conditions the decoder to accept the next arriving message signal allowed entry which has the unique address, whereupon the message signal command portion is decoded and a command signal is delivered to the remote equipment to be controlled.

US Patent:

52300889, Jul 20, 1993

Filed:

Oct 24, 1991

Appl. No.:

7/781925

Inventors:

John W. Kramer - Allison Park PA
Thomas J. Hutton - Cupertino CA

Assignee:

Symbol Technologies, Inc. - Bohemia NY

International Classification:

H04B 154
H04B 140
H04L 2704
H04L 2712

US Classification:

455 76

Abstract:

A radio transceiver for use in data communications uses a single phase-locked loop to control the frequency of the receiver portion while simultaneously providing coarse control of the frequency of the transmitter portion. The output of the receiver portion is also used to provide an error signal for fine tuning the transmitter frequency after the component of the error signal caused by modulation of the transmitter portion has been removed.

US Patent:

54188121, May 23, 1995

Filed:

Jun 26, 1992

Appl. No.:

7/904933

Inventors:

Wanda Reyes - Vale Drive CA
John W. Kramer - Allison Park PA

Assignee:

Symbol Technologies, Inc. - Bohemia NY

International Classification:

H04L 2730

US Classification:

375 1

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:

39640248, Jun 15, 1976

Filed:

Nov 15, 1974

Appl. No.:

5/524138

Inventors:

Thomas J. Hutton - Pittsburgh PA
John W. Kramer - Pittsburgh PA

Assignee:

Westinghouse Air Brake Company - Swissvale PA

International Classification:

H04Q 900
G01S 956

US Classification:

340152T

Abstract:

This disclosure relates to an inductively powered type of electronic transponder for identifying a moving object passing an interrogation area. The transponder includes a tuned inductive-capacitive pick-up circuit for receiving interrogating signals. The picked up interrogating signals are rectified to produce d. c. operating power and are applied to a frequency divider for producing a frequency related transmission signal and clock data rate pulse. A latching circuit enables a shift register so that the clock pulses serially shift out binary encoded data from the shift register. The encoded data is fed to a logic network which is coupled to a balanced switching amplifier for phase modulating the transmission signal for propagation into the interrogation area.