ETS-Lindgren 3186 Dual Stacked LPDA Antenna - Manual (Page 7)

www.ets-lindgren.com Introduction 7
1.0 Introduction
The ETS-Lindgren Model 3186 Dual Stacked Log Periodic Dipole Array
(LPDA) is comprised of two individual 100 Ω LPDAs. When assembled in
parallel, the results are a 50 Ω input impedance array. This array provides
increased gain when compared to a single LPDA, and provides a very constant
pattern across the entire frequency range.
Covering a frequency range of 1 GHz to 18 GHz, the Model 3186 is ideal as a
receive antenna for CISPR 16-based testing above 1 GHz. It can also be used
with the ETS-Lindgren Model 3183 End Fed Mini-Bicon antenna to perform the
site VSWR chamber validation method per CISPR 16.
The Model 3186 was designed to provide a constant illumination from 1 GHz to
18 GHz. The beamwidth in the two principal planes is 59.8 degrees for the
E-plane (the polarization plane) and 57.0 degrees for the H-plane (the orthogonal
plane), while the directivity is about 10 dB across the entire frequency range.
The Model 3186 includes a stinger mount and standard 1/4 –20 thread mounting
hardware. For all mounting options available for the Model 3186, see
Mounting Instructions on page 15.
Standard Configuration
 Model 3186 Dual Stacked LPDA
 Individually calibrated factors at 3m per SAE ARP 958