PARAMETRIC AMPLIFIERS FOR ELECTRONICALLY STEERABLE RADAR SYSTEMS.
Abstract
Criteria are presented for the design of an optimally reproducible, low-cost, high-performance, parametric amplifier for use in electronically steerable radar systems. The basic amplifier configuration is that of a circulator-coupled balanced varactor parametric amplifier with the varactor pair connected essentially at the ferrite junction reference plane at the amplifier port of the circulator. A new signal frequency equivalent circuit of a pumped varactor pair has been presented with all circuit element values characterized in terms of fundamental varactor quantities. An existing design theory for a linear phase parametric amplifier has been extended to yield gain- and phase-bandwidth limitations and required circuit element values in terms of fundamental varactor quantities. The theory indicates that the gain-bandwidth and phase-linearity objectives can be met using two cascaded 10-db linear phase amplifier stages, each using a balanced pair of silicon varactor diodes of quality factor 21, a self-resonant frequency of 14.5 GHz, a nonlinearity ratio of 0.3 and a pump frequency of 17.87 GHz. A prototype model of a three-port stripline circulator was constructed for use in this amplifier. Its performance has been optimized with respect to ferrite material and magnetic field intensity for a suitable, though not sufficiently broad-band impedance characteristic over the 3.1 to 3.7 GHz range. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1967
- Accession Number
- AD0808837
Entities
People
- Herman C. Okean