Experiments in weight design for a sombrero array pattern
- K. R. McPhail, J. O. Coleman, and D. P. Scholnik
- There is an interest in developing a transmit array
taper that illuminates both a highly directive cluster
of receive beams and a broad region of the sky at a
level that can support a ubiquitous radar function.
This report provides experimental optimization results
of a sombrero-shaped amplitude array taper that can be
used to implement two simultaneous functions of this
type. The amplitude tapers are optimized in two ways:
boresight radiated power density is fixed while
minimizing either max total transmitter power required
or max element power required. This report also
presents experiments with nonoptimized linear-FM and
nonlinear-FM phase-only tapers. The phase-only tapers
do improve the peak level loss that occurs in the
amplitude optimizations. We do not have the
capability to optimize phase-only weights, but intend
to give a designer a starting point for exploring
phase-only optimization of a sombrero-shaped array
- The Fig. 11 design was supposely subject to a 23 dB Taylor-like
shelf, but actually the shelf region was not made large enough to
properly constrain the inner sidelobes. The shelf began at 6.8 deg
but should have been started at something more like 6.3 deg. As a result
of this oversight, the inner sidelobe peaks at around 20 dB down.
- DOWNLOADABLE PREPRINT:
PDF (13.2 Mbytes),
- Published June 25, 2010 as NRL Memo Report 9232.
Approved for public release; distribution is unlimited.
- DATE OF ENTRY: