It is shown that amplitude intermodulation distortion (AIMD) in a feedback amplifier is associated primarily with signal-induced changes in the low-frequency gain of the forward path, whereas phase intermodulation distortion (PIMD) is associated primarily with signal-induced changes in the gain-bandwidth product. The usual nonlinearity in transistor ß therefore contributed AIMD but not PIMD. It is shown that both AIMD and PIMD involve intermodulation products at the same frequencies. For comparable nonlinearities other amplitudes of the intermodulation products are roughly equal, but their phases are different by -/2. An intermodulation specification based on the amplitude of the intermodulation products includes both AIMD and PIMD. In contrast, a specification based on the depth of an amplitude modulation neglects PIMD.

Author: Cherry, Edward M.
Affiliation: Monash University, Department of Electrical Engineering, Clayton, Vic. 3168, Australia
JAES Volume 31 Issue 5 pp. 298-304; May 1983
Publication Date: May 1, 1983

Click to purchase paper as a non-member or you can login as an AES member to see more options.

No AES members have commented on this paper yet.

Subscribe to this discussion

To be notified of new comments on this paper you can subscribe to this RSS feed. Forum users should login to see additional options.

Start a discussion!

If you would like to start a discussion about this paper and are an AES member then you can login here:
Username:
Password:

If you are not yet an AES member and have something important to say about this paper then we urge you to join the AES today and make your voice heard. You can join online today by clicking here.