Statistical Correlation of Gain and Buildup Time in APDs And Its Effects on Receiver Performance

Authors

Peng Sun, University of New Mexico
Majeed M. Hayat, Marquette UniversityFollow
Bahaa E.A. Saleh, Boston University
Malvin Carl Teich, Boston University

Document Type

Article

Language

eng

Publication Date

2-13-2006

Publisher

Institute of Electrical and Electronic Engineers (IEEE)

Source Publication

Journal of Lightwave Technology

Source ISSN

0733-8724

Abstract

This paper reports a novel recurrence theory that enables us to calculate the exact joint probability density function (pdf) of the random gain and the random avalanche buildup time in avalanche photodiodes (APDs) including the effect of dead space. Such calculations reveal a strong statistical correlation between the gain and the buildup time for all widths of the multiplication region. To facilitate the calculation of the photocurrent statistics in the presence of this correlation, the impulse-response function of the APD is approximately modeled by a function of time whose prespecified shape is appropriately parameterized by two random variables: the gain and the buildup time. The evaluation of the variance of the photocurrent under this model leads to the definition of the shot-noise-equivalent bandwidth of the APD, which captures the statistical correlation between the gain and the buildup time. It is shown that the shot-noise-equivalent bandwidth in GaAs APDs is greater, by approximately 30%, than the traditional buildup-time-limited 3-dB bandwidth, which is calculated from the mean of the impulse-response function. A thorough analysis of the performance of APD-based integrate-and-dump digital receivers reveals that the strong correlation between the gain and the buildup time accentuates intersymbol interference (ISI) noise, and thus, adversely affects receiver sensitivity at high transmission rates beyond previously known limits.

Comments

Accepted version. Journal of Lightwave Technology, Vol. 24, No. 2 (February 13, 2006). DOI. © 2006 Institute of Electrical and Electronic Engineers (IEEE). Used with permission.

Majeed M. Hayat was affiliated with University of New Mexico, Albuquerque at the time of publication.

Recommended Citation

Sun, Peng; Hayat, Majeed M.; Saleh, Bahaa E.A.; and Teich, Malvin Carl, "Statistical Correlation of Gain and Buildup Time in APDs And Its Effects on Receiver Performance" (2006). Electrical and Computer Engineering Faculty Research and Publications. 594.
https://epublications.marquette.edu/electric_fac/594