Small-Signal Amplification.
Abstract
The significance of this research to the Air Force is the availability of a new versatile, general-purpose solid-state microwave amplifier for frequencies above 3 GHz. In the prototype traveling-wave transistor, a transistor-like input launches a traveling space-charge wave, which grows exponentially as it moves along in a thin layer of n-GaAs to a relatively distant output. At the output the signal is enhanced further by built-in negative resistance. The long distance between input and output makes it feasible to optimize input and output independently and minimizes the feedback capacitance which often limits gain and bandwidth in high-frequency devices. Twelve experimental units show broad-band net gain in X-band, with 14 to 26 dB built-in isolation. One unit exhibits instantaneous net gain from 6.7 to 15.3 GHz; another yields 28 dB at 9.2 GHz. All devices are good for linear microwave signal processing: voltage-controlled phase modulation at constant net gain, or voltage-controlled gain modulation at constant phase. Different bias conditions make possible threshold-sensitive saturated-amplitude amplification of pulses or sinusoids, for logic or digital functions. A related two-terminal reflection amplifier has been demonstrated also. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1972
- Accession Number
- AD0892432
Entities
People
- Raymond H. Dean
Organizations
- Sarnoff Corporation