Newsgroups: sci.electronics Path: utzoo!henry From: henry@utzoo.uucp (Henry Spencer) Subject: Re: Bad News- Lasers replace Radar guns Message-ID: <1990Jan18.163107.15487@utzoo.uucp> Organization: U of Toronto Zoology References: <7263@lindy.Stanford.EDU> <349@egrunix.UUCP> Date: Thu, 18 Jan 90 16:31:07 GMT In article mikemc@mustang.ncr-fc.FtCollins.NCR.com (Mike McManus) writes: >> It can't be used while moving currently since it can't determine the police >> cars speed yet. > >Why is that? How do the current radar models work with respect to telling the >speed of the officer's car? Wouldn't it be similar? No; remember the laser system is doing distance measurement, while the radars are using Doppler velocity measurement. The radars simply measure the velocity of the background, which is always "in view" anyway because their beams are so broad. That doesn't work for the lasers. -- 1972: Saturn V #15 flight-ready| Henry Spencer at U of Toronto Zoology 1990: birds nesting in engines | uunet!attcan!utzoo!henry henry@zoo.toronto.edu