Alan L Lindstrum

US Patent:

41807936, Dec 25, 1979

Filed:

Apr 26, 1978

Appl. No.:

5/900211

Inventors:

Alan L. Lindstrum - Bainbridge Island WA

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

H04B 102
H04B 1100

US Classification:

367137

Abstract:

A phase shift keyed (PSK) pulse synthesizer which is part of an acoustic transmitter located in an underwater vehicle to provide identification and tracking of the vehicle as well as telemetry data when used on an instrumented underwater tracking range. The synthesizer is synchronized with the range time standard and generates phase coded pulses in a format suitable for input to an amplifier. A timing circuit divides a high frequency clock to produce square wave outputs at the desired frequency. A programmed read only memory (PROM) contains the identification code and is addressed from the timing circuit. A phase shift modulator combines the desired frequency with signals from the PROM and from a telemetry data generator to provide the amplifier with a digital analog of the desired acoustic message to be transmitted.

US Patent:

41874919, Feb 5, 1980

Filed:

Aug 7, 1978

Appl. No.:

5/931691

Inventors:

Alan L. Lindstrum - Bainbridge Island WA
Jay V. Chase - Poulsbo WA

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

G01S 518

US Classification:

367125

Abstract:

A Doppler compensated PSK signal processor which receives a plurality of sages from a sensor array and decodes each message for further data processing. The signal processor compensates for the Doppler shift in the message frequency due to the velocity differential between the transmitting vehicle and the sensor array. The message is decoded for a valid identification code from which is derived a time mark related to a specified system time to provide range and direction information for the identified transmitting vehicle. The telemetry data in the message and the time mark are output to a data processing system on an interrupt basis to provide tracking and data analysis for the transmitting vehicle.

US Patent:

43807453, Apr 19, 1983

Filed:

Nov 7, 1980

Appl. No.:

6/205027

Inventors:

Michael L. Barlow - Silverdale WA
Alan L. Lindstrum - Bainbridge Island WA

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

H03L 102

US Classification:

331176

Abstract:

A crystal oscillator that is temperature compensated by digitally substrang a correction frequency from the running frequency of the crystal oscillator to provide the required operating frequency. The correction frequency is generated by a digital frequency synthesizer circuit which is controlled by the output of a programmable read-only memory which has been programmed to generate the required correction frequency for each temperature code over the operating temperature range. The temperature code is generated by gating a digital counter with the output of a monostable multivibrator which utilizes a thermistor to make its gate interval proportional to temperature.