Robert M. Lerner   (Feb 1, 1928 - Dec 31, 2010)

I heard about the Lerner filter from a passing comment many years ago.  It is quite interesting, and somewhat surprising it is so rarely cited.

The first slides below show a passive LC implementation based on Lerner's paper from the March 1964 Proceedings IEEE.

The second slide set shows an active filter based on the 1973 patent of Kenneth DeWitt, assigned to Sonex, Inc.

Also of interest:

The 1983 patent 4395688 by Robert Sellers, assigned to Harris, Corp.   It is a passive filter using series connected parallel LC resonators, as opposed to the parallel connected series LC resonators in Lerner's paper.  (Lerner had indicated either could be used.)

The Feb 15, 1979 issue of Electronic Design contained an article by Arthur Delagrange, Bring Lerner filters up-to-date.   I have not found a copy, but related material appears in the 1987 Navy report,  An Active Filter Primer, Mod 2, which is available from the Defense Technical Information Center  here .   The third set of slides shows Delagrange topologies for bandpass, lowpass, and highpass responses.  The pole frequencies were tuned in the simulation by trial and error, and are perhaps not what the author had intended.

Delagrange also wrote the final chapter in the Jim Williams' 1998 book, The Art and Science of Analog Circuit Design.  The chapter references include a dozen sources written by Delagrange, but the Lerner filter is not included.  Perhaps it's significance is  more academic and historical than practical.

Postscript:   In addition to considerable published work in communication theory, Dr. Lerner received a patent for Ground (penetrating) Radar System, US pat 3831173 in 1974, assigned to MIT.