Four-Channel, High-Dynamic-Range Downconverter
Abstract
The David Sarnoff Research Center has developed, under a 24-month Naval Research Laboratory sponsored program, a four-channel, high-dynamic-range down-converter (HDRD) that will advance the state of the art in electronic warfare receivers by achieving a two-tone, spur-free dynamic range of 65 dB in a 50-MHz bandwidth. A spot check of the linear dynamic range measured 92 dB from the noise floor to the 1 dB compression point. There are several design features that lead to these excellent results. They include: (1) the use of wideband, low-noise, high intercept point MMIC amplifier chips for all of the amplifiers in the downconverter; (2) low-loss MMIC PIN-diode switches; (3) low-loss filters and diplexers; and (4) a high-dynamic-range mixer. The input frequency range of the HDRD is 6 to 18 GHz, and the output frequency (IF) is 3 to 5 GHz. It uses four local oscillator (LO) frequencies, 11, 13, 15 and 17 GHz, to downconvert the six, 2-GHz-wide subbands to the intermediate frequency. A switched filter bank, consisting of six 2-GHz-wide bandpass filters, provides the required frequency selection for the downconverter. Each branch of the filter bank includes an amplitude and phase trimming module to allow for the adjustment of the tracking among the four channels. The trimming module consists of T-pad attenuator chips and an adjustable length of 50-ohm transmission line.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1991
- Accession Number
- ADA245020
Entities
People
- E. J. Denlinger
- R. E. Askew
- R. W. Paglione
Organizations
- Sarnoff Corporation