This report summarizes the design of a digital frequency synthesizer for airborne distance measuring equipment. It is the purpose of the frequency synthesizer to provide a stable frequency source for the local oscillator of the airborne receiver and for the power amplifiers in the transmitter chain. The synthesizer is required to furnish a frequency ranging from 260.250 mHz to 287.50 mHz in channel steps of 250 kHz at a power level of +7.0 dBm. the stability of the frequency must be greater than .005% over the temperature range of from minus 45 degrees centigrade to plus 55 degrees centigrade, requiring a crystal controlled source. Digital techniques are employed using two crystal controlled oscillators to synthesize all required channel frequencies. Linear circuits using standard configurations are employed for the oscillators, buffers, and mixers. Primary attention is paid to optimizing the transient characteristics of the synthesizer which employ programmable digital counters to change the division ratio in a phase locked loop. Decoding is provided to interface the modulus of the counters with the aircraft cockpit controls.
Identifer | oai:union.ndltd.org:ucf.edu/oai:stars.library.ucf.edu:rtd-1182 |
Date | 01 January 1975 |
Creators | Sharpe, Claude A. |
Publisher | Florida Technological University |
Source Sets | University of Central Florida |
Language | English |
Detected Language | English |
Type | text |
Format | application/pdf |
Source | Retrospective Theses and Dissertations |
Rights | Public Domain |
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