Theoretical and Development Work on High-Efficiency Avalanche Diode Sources.
Abstract
Theoretical and developmental work on avalanche diode sources and amplifiers was carried out. Detailed results are presented for both high-power (greater than 1.5-W) C-band amplifiers and oscillators using IMPATT diodes. A four-diode amplifier was constructed that is capable of producing more than 8-W output with 6-dB gain and more than 5-percent efficiency in the vicinity of 5.2 GHz. The amplifier output could be increased to 10W but with lower gain (about 5 dB). This silicon avalanche diode amplifier had 7-percent, 1-dB bandwidth at the 8-W level and showed less than 1-percent FM distortion at moderate modulation indexes (>0.4). Measurements of the AM and FM noise showed it to be well below the specified level. In fact, measurements at 6-W output showed little difference between the FM noise measured from the avalanche diode amplifier driven by a 1.6-W klystron and the klystron alone. The high-power amplifier used a microstrip hybrid-circuit power combiner to combine the outputs of the four individually matched avalanche diode amplifier modules. The hybrid-circuit design improved existing designs by taking into account various parasitic effects present in microstrip circuits. Several IMPATT diode oscillators were constructed. A theoretical analysis of IMPATT diode efficiency was carried out to determine the practical limitations imposed by using silicon devices and the effects of parasitic resistance within the diodes and matching circuits. Theoretical and experimental investigation of a moderately high-efficiency mode of oscillation in avalanche diodes, termed the partial-plasma mode, was carried out. (Modified author abstract)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1972
- Accession Number
- AD0764262
Entities
People
- Allen F. Podell
- Don Parker
- Robert E. Lee
- Ulrich H. Gysel
Organizations
- SRI International