Article View: sci.electronics
Article #17266Re: Phase Jitter of a free-running oscillator
From: gibson
Date: Sat, 14 Feb 1987 18:27
Date: Sat, 14 Feb 1987 18:27
26 lines
1874 bytes
1874 bytes
In article <5246@reed.UUCP> mdr@reed.UUCP (Mike Rutenberg) writes:
>What is the "phase jitter of a free-running oscillator" and what does it
>depend on? Does anyone have any revealing references?
I'm not sure what your context is, but the only context in which I've
seen that phrase is in digital oscillators. If you use a digitally-
stored waveform and sequence through its points to generate a waveform
(sending each point to a DAC), I know of 2 definitions :
1) sample period jitter - unevenness in time between output samples.
The reference implies noise from this jitter is 83 dB below the
RMS level of a generated sine wave iff the sample period jitter
is < (0.0000118 / F) (sec), where F is the output frequency.
"Design of a digital oscillator...", John Snell, Computer Music
Journal 1(2):4-25, 1977
2) phase jitter - errors due to finite length of the stored waveform.
If you use a 256-point table and a 16-bit phase register, you
will get noise because the 8-bit address and the 16-bit phase
often refer to different points on the waveform (since the phase
must be truncated or rounded).
"Table Lookup Noise...", Richard
Moore, Computer Music Journal 1(2):26-29, 1977
Bill Gibson
gibson@unc ...[akgua,decvax,philabs]!mcnc!unc!gibson
Technical Details
Message-ID:
<919@unc.unc.UUCP>Path:
arc1-ca.pugleaf.net!utzoo!watmath!clyde!rutgers!brl-adm!seismo!mcnc!unc!gibsonReferences:
<5246@reed.UUCP>Show Full Headers
Complete Article Headers
Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: arc1-ca.pugleaf.net!utzoo!watmath!clyde!rutgers!brl-adm!seismo!mcnc!unc!gibson From: gibson@unc.UUCP Newsgroups: sci.electronics Subject: Re: Phase Jitter of a free-running oscillator Message-ID: <919@unc.unc.UUCP> Date: Sat, 14-Feb-87 13:27:40 EST Article-I.D.: unc.919 Posted: Sat Feb 14 13:27:40 1987 Date-Received: Tue, 17-Feb-87 05:49:23 EST References: <5246@reed.UUCP> Reply-To: gibson@unc.UUCP (Bill Gibson) Organization: CS Dept, U. of N. Carolina, Chapel Hill Lines: 26