Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!ukma!rutgers!cmcl2!dasys1!aj-mberg
From: aj-mberg@dasys1.UUCP (Micha Berger)
Newsgroups: sci.electronics
Subject: Re: Stereo vs. Mono: Q about AM Stereo
Message-ID: <9646@dasys1.UUCP>
Date: 14 May 89 12:31:37 GMT
References: <4046@bgsuvax.UUCP> <11170006@hpfcdj.HP.COM>
Reply-To: aj-mberg@dasys1.UUCP (Micha Berger)
Organization: none
Lines: 14


Actually, FM is inherently less noisy. I remember that much from my
communications course. Let's see if I can remember how.

In AM, the noise is basically the noise-spectral-density integrated over the
area around the carrier frequency. Thus, the wider the txmission bandwidth,
the more noise. In FM, increasing the modulation index increases the
bandwidth, but lowers the signal to noise ratio. The FM differs from AM
(100% modulated AM, of same output power) in signal to noise ratio by a factor
of 3B^2 where B is the modulation index (delta f / carrier f).
-- 

					Micha Berger                                                                                                            -------------------------------------v------------------------------------------"The world stands on three things: on| AishDas Society / Aspaklaria Publicationsthe Torah, on Service [to the L-rd], | 73-32 173 St, Hillcrest, NY 11366        and on Acts of Kindness"	     | (718) 380 - 7572                            - Shimon the Righteous, Avos 1:2  | email: ...cmcl1!dasys!aj-mberg
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