N4HY’s web page

Bob McGwier, N4HY



I’m in my natural state, at the keyboard.



Gerald_Bob_Frank_Phil_2007-10-26 Hi-Def_2.jpg

Left to Right:  Gerald Youngblood (K5SDR), me (N4HY), Frank Brickle (AB2KT), and Phil Covington (N8VB) at AMSAT 2007 Symposium




The Family says I need a mid-life crisis so I got a Honda S2000 surprise on Christmas.



Please read my blog: N4HY's Blog and please visit my picture site: http://n4hy.smugmug.com



 is the most important formula in signal processing.


My doctoral thesis, on nonlinear filtering, was concerned with dynamical systems of the form:



This is a stochastic differential equation and the last term is a Gaussian or Brownian motion stochastic process.  Nonlinear filtering concerns itself predicting the probabilistic behavior of the dynamical system when given an incomplete and/or noisy look at the “signal”  where the look takes this form:




Here h is a nonlinear function and again, v is a Gaussian or Brownian motion.  This stochastic differential system and its nonlinear observation equation are the theoretical underpinnings for the study of fully nonlinear phase locked loops.  In a numerical treatment of the nonlinear phase locked loops contained in my thesis, I was allowed to apply this to the Venus Halley Balloon probe signals.  The first few transmissions from the two balloon probes into the Venusian atmosphere were noisy, with high Doppler residual because of the probes penetration deep into the atmosphere of Venus.  This was one of the most thrilling things I have ever been involved in.


Twitter: rwmcgwier

AIM: bobmc0307

Jabber.org: n4hy