Brooke variance classification system for DF bearings
Journal of Research of the National Bureau of Standards Section D Radio Propagation
This paper d esc rib es t he a dvanLages of having an objective class ification syst e m for DF bearings . Th e Brooke system is d es cribed in some d etail, a nd the pro blems im'oh ed in setting up a sy stem on t hese lin es a re considered. 3 The co nventi onal just ification for this as a Confidence R egion is based On the ass um ption that all p :lssible bearing lines fro m a give n sta tion are approximately. parallel .. Bea le [1960J provides a method or justifyi ng it even when this
... even when this apprOX lln at lOl~ IS. u~l ac~cpta~)le. B eal~'s paper s hows that the a pproxima t e co nfidence reglOn IS Ju st i fied If a quantity ~ 1/>, called the" intrinsic nonlineari t y of the model" is sm a ller t han abont 0. 1. It seems likely that the DF proble m nearl y al ways satisfies thiS conditiOn; even though ono ca n eas il y imagine situations witl.l a "narrow base line" when the probl em is decidedly ilOnJincar when ex pressed III terms of natu ra l parameters, such as the latitud e a nd longitude 0 the transmitter. 255 , !